resource

DEPARTMENT OF PRIMARY INDUSTRIES AND ENERGY

BUREAU OF MINERAL RESOURCES, GEOLOGY AND GEOPHYSICS

RESOURCE REPORT 4

Gold deposits of Queensland: BMR Datafile (MINDEP)

C. M. MOCK, R.P. WRENZ & B.G. ELLIOTT

Resource Assessment Division

AUSTRALIAN GOVERNMENT PUBLISHING SERVICE CANBERRA 1988

DEPARTMENT OF PRIMARY INDUSTRIES AND ENERGY MINIsrER FOR RESOURCES: SENATOR THE HON PETER COOK SECRETARY: G.c. EVANS

BUREAU OF MINERAL RESOURCES, GEOLOGY AND GEOPHYSICS DIRECTOR: R W.R. RUTLAND AO

Published by the Australian Government Publishing Service for the Bureau ofMineral Resources, Geology and Geophysics

© Commonwealth of Australia 1988 This work is copyright. Apart from any fair dealing for the purpose of study, research, criticism or review, as permitted under the Copyright Act, no part may be reproduced by any process without written permission. Copyright is the responsibility of the Director, Publishing and Marketing, AGPS. Inquiries should be directed to the Manager, AGPS Press, Australian Government Publishing Service, GPO Box 84, Canberra ACT 2601.

ISBN 0644 08000 0 ISSN 0 818 - 6278

Database keyboarding and word-processing by D Ting. Line drawings by Cartography Section, BMR. Introductory pages prepared on Ventura desktop publisher by J Hoskin.

Printed in Australia by Graphic Services Pty Ltd, Northfield, South Australia

CONTENTS ABSTRACT

iv

INTRODUCTION

1

NOTES ON THE REPORT AND DATABASE HEADINGS

2

REFERENCES

2

FIGURES 1.

Locality map for gold deposits and deposit groups

.3

2.

Administrative subdivisions of Queensland

.4

3.

Structural units of Queensland

5

4.

Transitional orogenic igneous provinces of Queensland

6

1.

Deposits in the datafile

7

2.

Index to deposit names, synonyms, orebodies, and mines

8

TABLES

APPENDIXES 1. Mineral deposits (MINDEP) database recording format

16

2. Datafile sample: Kidston deposit

25

Datafile (on microfiche)

III

ABSTRACT Data are presented for 36 Queensland gold deposits. They include information on regional setting, locality, geology, and characteristics of the deposits and their host rocks, and a brief summary of proposed genetic models. Development history (including discovery and mining methods), resource and production data, and a bibliography are also presented. The data form part of BMR's MINeral DEPosits (MINDEP) database.

iv

INTRODUCTION This report is the second in the series of dataftles on Australian gold deposits, derived from BMR's MINeral DEPosits database (MINDEP). The first, on Western Australian deposits, was released in 1987 (Mock & others, 1987). Like the data for Western Australia, the Queensland data are available in several formats: (1) microfiche, (2) 5 1/4" diskette (IBM PC/ASCII/DOS3.1), (3) hard-copy computer printout, and (4) 1600 bpi magnetic tape. The datafue contains information on 36 major historical and new Queensland gold deposits. The information in the database and this report were compiled by Colleen Mock using the MINDEP format for recording data (Appendix 1) developed in the Resource Assessment Division. The structure of the database was devised by Rae Lorenz and developed with ORACLE software on a Data General MV 20 000 minicomputer. Brian Elliott is the project co-ordinator. Queensland's gold deposits display an enormous diversity of style and geological association. The bulk of the State's gold production of some 770 000 kg was won between 1867, when gold was first discovered at Gympie, and the early decades of this century. The main sources were rich reef or alluvial deposits at Charters Towers, Mount Morgan, Gympie, Palmer River and Cracow, with smaller contributions from Croydon, Ravenswood, Etheridge and others (Fig. 1). However, many factors contributed to the rising cost of gold extraction and consequent early closure of most operations, among them the harshness and remoteness of the environment, and the increasing difficulty of mining and treating deep complex sulphide ores (e.g. Ravenswood), combined with undercapitalisation of the minesAs a result, many deposits were never efficiently explored or developed. From 1930 to 1980 Mount Morgan and Cracow were the mainstay of Queensland's gold mining industry. In Queensland, as elsewhere, the sustained high price of gold since 1980 led to a resurgence of gold exploration. Equipped with modern technology and a better understanding of Queensland's complex geology, explorers have delineated not only deeper and/or lower-grade extensions to known deposits, but have identified geological environments that are prospective for new styles ofgold mineralisation. The PermoCarboniferous volcanic/plutonic province of northern Queensland has been successfully targeted for epithermalstyle mineralisation at Kidston, Pajingo, and elsewhere, and for skarn mineralisation at Red Dome and Harpers. In southern Queensland, epithermal-style deposits are associated with the Permo-Triassic volcanic/plutonic province at Agricola, Mount Rawdon, and elsewhere. As a result of new development, principally at the large, open-cut Kidston mine, now one of Australia's top gold producers, Queensland's gold production has risen in recent years from around 1000 kg annualy to about 15000 kg in 1987. Other major projects developed since 1985 or under development in early 1988 include Horn Island, Red Dome, Mount Leyshon, Pajingo, Agricola, Croydon, Cracow, Kilkivan, Ravenswood, Starra, and Wirralie. Styles of gold mineralisation in Queensland can be broadly correlated with tectonic regime (Horton, 1987; Murray, 1986; Day & others, 1983). Proterozoic orogenic zones are represented by the Mount Isa, Georgetown, Cocn, and Yambo Inliers (Fig. 3). In the metasedimentary-metavol-

canic succession of the Eastern Fold Belt of the Mount Isa Inlier, gold mineralisation occurs in structurally controlled copper deposits (Cloncurry) and quartz-hematite bodies in banded-iron-formation (Starra). In the Georgetown Inlier, gold vein deposits are associated with the metasedimentary succession at Gilberton, with late-orogenic granite at Georgetown, Forsayth, and Percyville, and with late-orogenic high-level granite and felsic volcanics at Croydon. In the Palaeozoic, the Thomson and Hodgkinson-Broken River Orogens developed on the eastern margin of the Proterozoic craton. The Thomson Orogen is preserved in the Lolworth-Ravenswood Block, Anakie Inlier, and the transitional tectonic Drummond and Burdekin Basins. The Hodgkinson-Broken River Orogen is preserved in the Hodgkinson Basin and adjacent blocks. Some important gold deposits that formed at the orogenic stage were slate-belttype auriferous quartz-sulphide veins in the Hodgkinson Basin (Hodgkinson group of deposits: Palmer River, Fine Gold Creek, Tregoora, Hodgkinson, Belfast HiII).Major vein deposits are associated with late-orogenic granite batholiths in the Lolworth-Ravenswood Block (Charters Towers, Disraeli, some deposits at Ravenswood). In the Late Carboniferous-Late Permian, much of northern Queensland including the Cape York-Oriomo Inlier, Hodgkinson Basin, much of the Georgetown Inlier, and the northern part of the Thomson Fold Belt, were affected by the intrusion of post-orogenic granitic batholiths and the eruption of comagmatic silicic volcanics (Fig. 4). Numerous vein, lode, breccia-pipe and skarn deposits are associated with the Permo-Carboniferous igneous activity: Kidston in the Georgetown Inlier, Horn Island in the Cape YorkOriomo Inlier, Mount Leyshon, Cape River, some Ravenswood deposits in the Lolworth-Ravenswood Block, Red Dome and Harpers in the Hodgkinson Basin, Pajingo, Wirralie, and Mount Coolon in the Drummond Basin, and Far Fanning in the Burdekin Basin. The Georgetown group of deposits had a complex history of formation, apparently involving late Palaeozoic granitic plutonism in the final mineralising episode. From the middle Palaeozoic to the Mesozoic, the New England Fold Belt evolved eastwards from the earlier Palaeozoic fold belts (Fig. 3). Major gold deposits were associated with orogenic volcanic arcfbasin systems: volcanogenic massive gold-copper sulphides at Mount Morgan (probably) in the Calliope Block, Mount Chalmers in the Berserker Graben, and Cracow (probably) at the margin of the Bowen Basin; and slate-belt-type veins at Gympie. Clermont is a large placer deposit in conglomerate correlated with the basal sediments of the Bowen Basin. The southern part of the New England Fold Belt was extensively affected by transitional orogenic plutonism and volcanism in the Late Permian-Late Triassic (Fig. 4).Numerous, generally small but rich gold vein and breccia-pipe deposits are associated with the Permo-Triassic igneous province: Eidsvold, Mount Cannindah, Kilkivan, Agricola, and Mount Rawdon. Gold mineralisation in the northern part of the New England Fold Belt is principally associated with a younger, Cretaceous phase of transitional tectonic plutonism (e.g. Dittmer).

NOTES ON THE REPORT AND DATABASE HEADINGS Appendix 1 shows the MINDEP database recording format. Appendix 2 (Kidston deposit) illustrates the format of the datafue . Table 1 lists the deposits in the order in which they appear in the datafile, from north to south on the map (Fig. 1). Table 2 is an alphabetical index to the deposits, orebodies, mines, and synonyms. The following notes should be read in conjunction with Appendix 2. 'DEPOSIT INDENTIFICATION' includes administrative subdivision (Fig. 2), known synonyms for the deposit, the various mines and orebodies within the deposit, and the principal commodities mined. This section of the report also includes the deposit 'group'. The geological data have been recorded on a hierarchical basis to provide for flexibility of storage and ease of retrievalAs well as having been assigned to structural units (block, province, subprovince: see 'GEOLOGY'), where appropriate deposits have been grouped on the basis of a common geological affiliation. To avoid repetition, the geological setting that applies to all members of the group is given under only one (usually the principal) deposit of the group and can be cross-referenced via the 'Deposit Comments' field. It should be noted that the terms 'group', 'deposit', and 'orebody' have not been strictly dermed in geological terms and are to be regarded mainly as data storage and retrieval tools. 'DEVELOPMENT HISTORY' lists historical and modern operations separately. The 'PRODUCTION' data presented are totals only. Annual production data, from 1965 onwards, have been compiled and will be added to the database. 'RESOURCE' data were extracted from company reports to the Stock Exchanges and are classified according to the mineral resource classification system used by BMR (BMR, 1984). 'Pre-mine resource size' lists a deposit as 'small' «25 tAu), 'medium' (25-500 tAu), or 'large' (> 500 tAu), thus allowing for cross-referencing between MINDEP and the databases used in various map projects in progress or planned, such as the BMR Earth Science Atlas, Third Atlas of Australian Resources minerals maps, and Circum-Pacific Map Project - mineral resources maps. Mine capacity data are contained in the database, but are not reported in the datafue. Under 'GEOLOGY', deposits have been assigned to structural units (blocks, provinces and sub-provinces) as defined by Day & others (1983) (Fig. 3). Because of the importance of regional geological setting in gold exploration, particularly in Queensland, resumes of the geological setting of the blocks and, where appropriate, the block subdivisions, have been included under one deposit from each structural unit. The resumes are from Day & others (1983) and Murray (1986). The regional information is cross-

2

referenced via the 'Deposit Comments' field. Deposits may have associated with them a number of mines and orebodies. Data that are orebody- or minespecific are presented under the relevant orebodyor mine. For example, most of the geological information is orebody-specific, rather than deposit-specific; hence for each deposit there is a principal orebody whose description contains information relating to the deposit as a whole. Details specific to individual orebodies or mines such as dimensions and company participation are presented separately against the relevant orebody or mine name. Deposit type, under 'DEPOSIT CHARACTERISTICS', is a non-genetic classification of the deposit based on morphology and host rock association. 'REFERENCES' are current to December 1987 and contain data sources consulted plus sources of additional information. The complete bibliography for the gold database has been published separately (Mock, 1988).

REFERENCES BMR, 1984 - BMR refines its mineral resource classification system. Australian Mineral Industry Quarterly, 36(3), 73-82. DAY, R W, WHITAKER, W G, MURRAY, C G, WIlr SON, I H, & GRIMES, K G, 1983 - QUEENSLAND GEOLOGY. A companion volume to the 1:250 000 scale geological map (1975). Geological Survey of Queensland, Publication 383. HORTON, D J, 1987-Framework of acid volcanic-hosted bulk tonnage gold mineralisation in Eastern Australia. In HERBERT, H K (Editor)--Gold in Queensland. Proceedings of one-day symposium, University of Queensland, June 1984. University of Queensland, Department of Geology, Papers, 12(1),17-33. MoCK, C M, 1988 - Australian gold deposits--selected references, late 1800s-1987. AESIS Special List No. 25. Australian Mineral Foundation, Adelaide. MOCK, C, ELLIOTT, B G, EWERS, G R, & LORENZ, RP, 1987 - Gold deposits of Western Australia: BMR datafile (MINDEP). Bureau of Mineral Resources, Australia, Resource Report 3. MURRAY, C G, 1986 - Metallogeny and tectonic development of the Tasman Fold Belt System in Queensland. In SCHEIBNER, E (Editor) - Metallogeny and tectonic development of eastern Australia. Ore Geology Reviews 1(2-4), 315-400.

138"

144'

150 0

12'

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I I I I I

I I Mount Isa o

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I SOUTH AUSTRALIA

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I

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OUEENSLANO NEW SOUTH WALES 15/0/31

300km

)

'1

Gold deposit

....

Gold deposit group

Figure 1. Locality map for gold deposits and deposit groups.

144

150

TORRES STRA~ToHom Island Prince of Wales IslandU

le;

LWEIPA

\ THURSDAY ISLAND

(

12"

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Cooktown

Cooktown. Palmar

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SOUTH AUSTRALIA

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Mining district

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Figure 2. Administrative Subdivisions of Queensland (from Queensland Department of Mines State Series map 1: Major administrative areas, 1:250 000 scale, 1st edition, 1985).

150" YORK-OR/()M'O 1NL/ER

TORRES Prince of Wales

I

I I I I I

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& others (1983))

300km I

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D

Silunan-Tnasslc (New England Orogen) Ordovlclan-Carbonlferous (Hodgkrnson-Broken River Orogen) Transitional Devonian-Carboniferous basins Cambnan-OrdoVIClan

1 J

Precambrian

Figure 3. Structural units of Queensland (based on Day & others, 1983).

Thomson Orogen

t 5/0/33

138"

144"

150"

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SOUTH AUSTRALIA

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LATE TRIASSIC

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~

A

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Volcanics

Figure 4. Transitional orogenic igneous provinces of Queensland (based on Day & others, 1983).

Table 1. Deposits in the datafile

1 Horn Island 2 Palmer River 3 Fine Gold Creek 4 Tregoora 5 Hodgkinson 6 Belfast Hill 7 Red Dome 8 Harpers 9 Croydon 10 Georgetown 11 Forsayth 12 Kidston 13 Percyvi lle 14 Gilberton 15 Cloncurry 16 Starra 17 Cape River 18 Far Fanning 19 Charters Towers 20 Mount Leyshon 21 Disraeli 22 Ravenswood 23 Pajingo 24 Dittmer 25 Wi rrali e 26 Mount Coolon 27 Clermont 28 Mount Chalmers 29 Mount Morgan 30 Mount Cannindah 31 Mount Rawdon 32 Cracow 33 Eidsvold 34 Kilkivan 35 Gympie 36 Agricola

7

Table 2. Index to deposit names, synonyms, orebodies and mines.

Agricola Agricola Agricola Alexander Anglo-Saxon Anglo-Saxon Answer Aurora Band Of Hope Bank Of England Battle Axe Beaconsfield Beaconsfield Belfast Bel fast Flat Belfast Hill Belfast Hill Belfast Hill Better Luck Big Reef Big Reef Black Jack Black Jack Black Jack Black Johnsons Black Knight Black Knight Black Ridge Black Ridge Bonnie Dundee Brilliant Brilli ant Brilliant And St. George Brilliant Block Brilliant Central Brilliant Extended Buck Reef Caledonia Caledonian Caledonian (Goldsmiths) Caledonian (Goldsmiths) Cape River Cape River Cape River Cape River Cement Hill Charters Towers Charters Towers

8

36 Mine 36 Site 36 Orebody 2 Orebody 3 Orebody 3 Mine 15 Orebody 10 Orebody 19 Mine 18 Orebody 22 Orebody 5 Orebody 5 Mine 6 Synonym 6 Orebody 6 Mine 6 Site 6 Orebody 10 Orebody 11 Orebody 11 Mine 19 Mine 22 Orebody 19 Orebody 27 Orebody 4 Orebody 4 Mine 27 Mine 27 Orebody 19 Mine 19 Mine 19 Orebody 19 Mine 19 Mine 19 Mine 19 Mine 22 Orebody 10 Orebody 35 Orebody 11 Orebody 11 Mine 36 Mine 17 Orebody 17 Mine 17 Site 27 Orebody 19 Mine 19 Site

Charters Towers City Of Glasgow City Of Glasgow Clarks Gold Mines Clarks Moonstone

19 10 10 19 19

Clermont Clermont Clermont Cloncurry Cloncurry Cloncurry Columbia Columbia Commissioners Hill Commissioners Hill Cornishman Cracow Craven Croydon Croydon Croydon Cumber land Cumber land Cumber land Dan O'Connel1 Dawn Day Dawn Day Dawn Block And Deep Mines Disraeli Disraeli Disraeli Dittmer Dittmer Dittmer Duchess Duffer Duke Of Edinburgh Duke Of Edinburgh Durham Durham Eastward Ho Eidsvold Eidsvold Eidsvold Eldorado Etheridge Etheridge Excelsior Far Fanning Far Fanning Far Fanning Federation

27 Mine 27 Site 27 Orebody 15 Mine 15 Site 15 Orebody 35 Orebody 19 Orebody 14 Orebody 14 Mine 21 Synonym 32 Site 33 Orebody 9 Mine 9 Site 9 Orebody 10 Orebody 10 Mine 19 Orebody 19 Mine 32 Orebody 19 Orebody 19 Mine 22 Mine 21 Mine 21 Site 21 Orebody 24 Mine 24 Site 24 Orebody 15 Orebody 24 Orebody 22 Orebody 22 Mine 10 Orebody 10 Mine 19 Mine 33 Orebody 33 Mine 33 Site 35 Mine 10 Synonym 11 Synonym 32 Orebody 18 Mine 18 Site 18 Orebody 9 Mine

~yndham

Orebody Orebody Mine Mine Orebody

9

Ferneyside Fiery Creek Fine Gold Creek Fine Gold Creek Fine Gold Creek Fluorspar Flying Pig Forsayth Forsayth Forsayth General Gordon (Kirkton) General Grant General Grant General Grant General Wyndham Claims Georgetown Georgetown Georgetown Gi lbert River Gilberton Gilberton Gilberton Gi lded Rose Gi lded Rose Glanmire Glasgow Glencoe Glittering Hills Gold Top Golden Alexandra (Washington) Golden Gate Golden Gate 1 North Golden Gate Consols Golden Hill Golden Horn Golden Horn Golden Mile Golden Plateau Golden Plateau Golden Plateau Golden Valley Golden Valley Golden West Goldfinger Goldfinger Grant And Sunset Extended Great Caesar Great Eastern Great Eastern Groganville Gympie Gympie Gympie

10

32 2 3 3 3

Orebody Mine Orebody Mine Site

8 Synonym 5 Orebody 11 Orebody 11 Site 11 Mine 22 Orebody 5 Orebody 22 Mine 22 Orebody 19 Mine 10 Orebody 10 Site 10 Mine 14 Synonym 14 Orebody 14 Mine 14 Site 15 Mine 15 Orebody 35 Orebody 35 Orebody 9 Mine 36 Orebody 34 Orebody 19 Orebody 9 Orebody 9 Mine 9 Mine 22 Mine 20 Orebody 20 Mine 32 Orebody 32 Mine 32 Orebody 32 Synonym 18 Orebody 9 Orebody 32 Orebody 27 Mine 27 Orebody 22 Mine 18 Orebody 35 Orebody 35 Mine 3 Synonym 35 Orebody 35 Mine 35 Site

Hampden Harp Of Erin Harpers Harpers Harpers

15 9 8 8 8

Havelock Havelock Highland Mary Caledonia Highway Highway Hodgkinson Hodgkinson Hodgkinson Homeward Bound Homeward Bound Horn Island Horn Island Horn Island Ida-Comet Identity Iguana-Lady Mary Imperial Inglewood International Janet 'A' Janet 'B' Joes Del i ght John Bull John Bull (Sandy Creek) Just- In-Time Kellys Queen Block Keni lworth Kidston Kidston Kidston Kil kivan Kilkivan Kilkivan King Of Croydon-Richmond Kingsborough Kitty O'Shea Klondyke Koala Lady Augusta (Stockman) Lady Maria Lady Mary Lady May Lamberts Surprise Lancashire Lass Lancashire Lass No. 1 West Lane Creek Limerick Hill Limerick Hill East

11 Orebody 11 Mine 9 Orebody 19 Mine 19 Orebody 5 Orebody 5 Mine 5 Site 13 Orebody 9 Orebody 1 Orebody 1 Mine 1 Site 2 Orebody 19 Orebody 9 Orebody 19 Orebody 35 Orebody 10 Orebody 23 Orebody 23 Orebody 21 Orebody 19 Orebody 22 Orebody 19 Orebody 19 Mine 36 Synonym 12 Orebody 12 Mine 12 Site 34 Orebody 34 Mine 34 Site 9 Orebody 5 Orebody 18 Orebody 32 Orebody 26 Orebody 33 Orebody 19 Orebody 35 Orebody 36 Orebody 32 Orebody 18 Orebody 18 Orebody 10 Orebody 6 Orebody 6 Orebody

Orebody Orebody Orebody Site Mine

11

Limerick Hill Uest Limestone Creek Little Grand Junction Lolworth London London London North Long Tunnel Lord Byron Lord Byron Lord Nelson Louisa Lower Cape Macks Knob Maid Of Erin Main Lode Main Pipe Mark Twain Mary River Maytown Mcmasters Melaneur Miclere Miclere Mills Day Dawn United Mitchell River Mitchell River Mitchell River Monk land Monk land Moonstone Moonstone Moonstone (Cross) Mount Cannindah Mount Cannindah Mount Cannindah Mount Cannindah East Mount Cannindah East Mount Cannindah Mine Mount Cannindah Mine Mount Chalmers Mount Chalmers Mount Chalmers Mount Clearview Mount Coolon Mount Cool on Mount Coolon Mount Ell iott Mount Emu Mount Freda Mount Freda Mount Hogan Mount Hogan

12

6 3 22 17 22

Orebody Synonym Orebody Orebody Orebody

22 Mine 22 Mine 34 Orebody 10 Orebody 10 Mine 10 Orebody 2 Orebody 17 Orebody 12 Orebody 33 Orebody 28 Orebody 29 Orebody 9 Orebody 35 Mine 2 Synonym 27 Orebody 22 Orebody 27 Mine 27 Orebody 19 Mine 4 Synonym 4 Orebody 4 Mine 35 Orebody 35 Mine 9 Orebody 19 Orebody 19 Orebody 30 Orebody 30 Mine 30 Site 30 Orebody 30 Mine 30 Orebody 30 Mine 28 Orebody 28 Mine 28 Site 17 Orebody 26 Orebody 26 Site 26 Mine 15 Orebody 17 Orebody 15 Mine 15 Orebody 13 Orebody 18 Orebody

Mount Mount Mount Mount Mount

leyshon leyshon leyshon leyshon (Historical O/C) Macal ight

20 20 20 20

Mount Mount Mount Mount Mount Mount Mount Mount Mount Mount Mount Mount

Mascotte Mcnamara Morgan Morgan Morgan Rawdon Rawdon Rawdon Remarkable Rose Ross Stewart

15 Orebody 15 Orebody

Mount Success Mount Success Mount Wright Mount Wright Mountain Maid Mungana New Brilliant Freeholds New England New Queen New Queen Central New Zealand New Zealand Ni l Desperandum Ni l Desperandum No. 2 South Great Eastern No. 3 And 4 South No. 5 South North Australian North Australian North Glanmi re North Knob North Phoenix North Smithfield Northcote Northcote Oakville Old Man Old Queen Cross Orchid Orient Orient Oriental Oriental Overlander Painus

Orebody Mine Site Orebody 18 Orebody

29 Orebody 29 Mine 29 Site 31 Orebody 31 Site 31 Mine 17 Orebody 33 Orebody 23 Orebody 17 Orebody 18 Mine 18 Orebody 22 Orebody 22 Mine 9 Orebody 7 Synonym 19 Mine 22 Orebody 19 Mine 19 Mine 35 Orebody 35 Mine 11 Orebody 11 Mine 35 Mine 9 Mine 9 Mine 19 Mine 19 Orebody 35 Mine 12 Orebody 35 Mine 35 Mine 5 Orebody 5 Mine 13 Orebody 10 Orebody 19 Orebody 23 Orebody 35 Orebody 35 Mine 35 Orebody 35 Mine 22 Orebody 22 Orebody

13

Pajingo Pajingo Pajingo Palmer Palmer River Palmer River Palmer River Palmerville Papa Peak Downs Percy River Percy River Percy River Percyvi lIe Percyville Percyville Phoenix Pumpkin Gully Queen Queen Queen Of Croydon-Waratah Queenslander Queenslander Rainbow Claims Rainbow lease Rainbow-Wyndham Ravenswood Ravenswood Ravenswood Ravenswood Deep Mines Red Dome Red Dome Red Dome Red Streak Revival Rise And Shine Rishton Roma North Roses Pride Ruby Saratoga Sarsfield Scott Scott Scottish Scottish Gympie Selwyn Shamrock Shamrock Shelmalier Smithfield Soldiers Cap Southern Cross

14

23 23 23 2 2

Orebody Mine Site Synonym Orebody

2 Mine 2 Site 2 Mine 10 Orebody 27 Synonym 13 Synonym 13 Mine 13 Orebody 13 Orebody 13 Mine 13 Site 35 Orebody 15 Orebody 2 Orebody 19 Orebody 9 Orebody 11 Orebody 11 Mine 19 Mine 19 Mine 19 Orebody 22 Orebody 22 Mine 22 Site 22 Mine 7 Orebody 7 Mine 7 Site 22 Orebody 32 Orebody 34 Orebody 21 Synonym 32 Orebody 32 Orebody 19 Orebody 22 Mine 22 Orebody 23 Orebody 23 Mine 35 Orebody 35 Mine 16 Synonym 34 Orebody 34 Mine 22 Orebody 35 Orebody 15 Orebody 5 Orebody

Spero Me l i ora Spotted Calf St. George St. George St. George

10 18 10 19 10

Orebody Orebody Orebody Orebody Mine

St. Patr ick St. Patri ck Starra Starra Starra Stockholm Stockholm Stockholm (Comstock) Stockholm (Cross) Stuart Town Stuart Town Sugar loaf Sunburst Sunset Sunset Swedenborg Tabletop Tabletop Tansey Terrible Creek Thornborough Tregoora Tregoora Trekelano True Blue-Lady Isabelle-Content Twelve Mile Tyrconnel Union Union Union Jack Upper Cape-Gorge Creek Victoria Victoria And Caledonia Block Victory Victory Waratah Wellington-Lord Nelson West Lode Wexford White Hope Who'D A Thought It Wirralie Wirralie Wirral ie Wirral ie West Wi ses Hill \oIises Hill Woodville Woodville

19 19 16 16 16 19 19 19 19 5 5 29 19 22 22 19 9 9 34 2 5 4 4 15 9 9 5 5 5 22 17 19 19 35 19 9 19 28 10 32 22 25 25 25 25 12 12 5 5

Mine Orebody Orebody Mine Site Mine Orebody Orebody Orebody Orebody Mine Orebody Mine Orebody Mine Orebody Mine Orebody Orebody Mine Orebody Orebody Site Orebody Orebody Orebody Orebody Orebody Mine Orebody Orebody Mine Mine Orebody Orebody Orebody Orebody Orebody Orebody Orebody Orebody Orebody Mine Site Orebody Orebody Mine Orebody Mine

15

(j)

Appendix 1.

Mineral deposi ts (MINDEP) database recording fomat

October 1987 MINERAL DEPOSITS DATABASE - MINDEP-RECORD FORM

1

1. RECORD/DEPOSIT IDENTIFICATION

DEPOSIT NAME

DEPOSIT NO.

SYNONYMS

RECORD TYPE

FILE NO. . s(single)/c(compound)/p(partial)

PRINCIPAL COMMODITY(IES)

OREBODY(IES)

MINE(S)

MINOR COMMODITY(IES) DEPOSIT SIZE

l(large)/m(medium)/s(small)

DEPOSIT DISTRIBUTION

RECORD/DEPOSIT COMMENTS DEPOSIT TYPE(S)

2.LOCATION LATITUDE

1:100 000 MAP SHEET NO.

1:250 000 MAP SHEET NAME

STATE

LONGITUDE

METHOD OF LOCATION verified map ref.

1:250 000 MAP SHEET NO.

published

(Qld/NSW/Vic/Tas/SA/WA/NT)

determined LOCATION COMMENTS

REFERENCE POINT shaft open cut

plant town

centroid

3. GEOLOGY

DEPOSIT NAME

ADMINISTRATIVE SUBDIVISION(S)

HOST ROCKS LITHOLOGY:

2.

(1 )

FORMATION NAME:

AGE:

FORMATION NAME:

AGE:

FORMATION NAME:

AGE:

GEOLOGICAL PROVINCE/BASIN RELATIONSHIP TO MINERALISATION STRATIGRAPHIC AGE HOST SEQUENCE:

MINERALISATION: LITHOLOGY:

IGNEOUS INTRUSION:

(2 )

RELATIONSHIP TO MINERALISATION

GEOCHRONOLOGY LITHOLOGY:

(3)

RELATIONSHIP TO MINERALISATION GENETIC CONTROLS

GENETIC MODELS

m

3. GEOLOGY cont'd NAME:

DEPOSIT NAME ORE BODY NAME

TYPE OF BODY:

DIMENSIONS Strike length True width Vertical depth Down-dip depth Depth of oxidation Depth of cover Area

MIN

AVE m cm/m m m ~m

m km2

MAX

______--'m

_______cm/m

_____.....;m _______cm /m

______.....:m ______.....:m

______~m

OREBODY FORM(S) conformable discordant stratabound stratiform

______.....;m ______.....;m _______m

______--'m

_____.....;m ____km2

O/G

3.

_______km2 NATURE OF MINERALISATION

OREBODY MORPHOLOGY orebody/ore shoot

OREBODY ORIENTATION orebody/ore shoot

tabular lenticular - - - pipe-like irregular

folded flat-lying sheeted network

Primary ore

orebody/ore shoot __

strike dip pitch plunge

direction(s)

vein (reef) lode (alt'n zone) multiple veins stockwork breccia saddle reef bed

Secondary ore detrital (alluvial) supergene enrichment laterite/bauxite deep lead

LOCAL GEOLOGICAL ENVIRONMENT Structural features fracturing faulting shearing folding fold axis schistosity

Igneous activity volcanism sub-volcanism plutonism

Structural/strat. intersection(s)

ORE TEXTURE Favourable lithology(ies)

fault/fault fault/fold stratig. bdry. __ intr. contact fold/fold flt/strat.bdry__ flt/strat.unit__

BIF mafic int. ultramafic felsic porph. __ granitic mafic extr. chert

carbonate clastic sed. volcanogenic sed. metasedimentary mafic igneous felsic extrusive intermed. intrusive laterite

massive disseminated banded/laminated zoned oxidised primary free milling refractory

3. GEOLOGY

cont'd

GEOLOGICAL SETTING OF MINERALISATION

METAMORPHISM MINERALOGY

ALTERATION

DEPOSIT NAME OREBODY NAME

4.

N

o

PRESENT OPERATOR(S)/EQUITY

DEPOSIT NAME

5.

PRESENT OWNER(S)/EQUITY

DISCOVERY HISTORY Name

Type of body

Year

Method(s)

Body: Select from: Deposit / Orebody Method: Select from: Prospecting / Geochemistry / Drilling / Geology / Geophysics / Extension to known mineralisation / Other (state) PRODUCTION HISTORY Mine

Start year

End year

Production type

Method

Production type: Select from: Original/Modern / Main production periods / Other (state) Method: Select from: Underground / Heap leach / Open cut / Alluvial/Other (state) Current status: Select from: Operating / Non-operating / Historical/Other (state) COMMENTS:

Current Status

DEPOSIT NAME

RESOURCES

1'--

-----'

6.

Item:

Name

Metal: l. Material: l. 2. Units Grade Quantity Data ears~ from to Units~ status - - - -

i"-.

Facility Type

Contained metal Cut-off grade Classification Quantity Metal Data Units Grade Metal Data Metal Data status status BMR Company - - - - - - status --- --

Type: Select from: Mining centre I Deposit I Orebody I Mine I Mill I Dump I Other (stat~e~)~__~ 1. Specify metal(s) or commodityCies) and type of material, e.g. ~, Pb-Zn , Cu-Au ~ ul ore o/c ore 2. Select from: Ore grade I Reserve grade I Recoverable grade I Other (state) Data status: Select from: leave blank (data item is actual, reported, installed or calculated) I e(estimated by company) I f(forecast by company) COMMENTS:

N

N N

CAPACITY

DEPOSIT NAME 1 tern:

Facility Name

Type

Metal: 1. 2. Material: 1. Quantity Data Grade Units .'ears~ from to Units - - status - -

"'"

--

----'

1. 1.

2. Metal Data Recovery Data Quantity Data Grade Units - - status rate (%) status - - status - - - -

Metal Data Recovery Data - - status rate (%) status

Type: Select fran: Mining centre I Deposit I Orel:xxiy I Mine I Mill I D.lmp I Other (state) []'i;L], Pb-Zn '\ o/c Cu-m ore J ~ u/g or 2. Select fran: Ore grade I Reserve grade I Recoverable grade I Other (state) Data status: Select fran: leave blank (data item is actual, reported, installed or calculated) I e (estimated by canpany) I f (forecast by canpany)

1. Specify metal(s) or cannodity(ies) and type of material, e.g.

CCM1ENTS:

7.

PROOOCTION

DEPOSIT NAME 1

~:

Facility Name

Type

Metal: 1. Material: 1. 2. "ears~ Quantity Data Grade Units I+ rom to Units - - status - - - -

_

1. 1.

2. Metal Data Recovery Data Quantity Data Grade Units status rate (%) status - - status - - - -

--

Metal Data Recovery Data - - status rate (%) status

i

I !

,

Type: Select fran: Mining centre I Deposit I Ore1xxiy I Mine I Mill I Dump I Other (state) 1. Specify metal(s) or cannodity(ies) and type of material, e.g. Pb-Zn or ul ore olc ore 2. Select fran: Ore grade I Reserve grade I Recoverable grade I Other (state). Data status: Select from: leave blank (data item is actual, reported, installed or calculated) I e (estimated by canpany) I f (forecast by canpany)

IAuJ'

CCM1ENTS:

N W

8.

'Ri-Au

I

REFERENCE LIST GEODX REFNl

DEPOSIT NAME REFERENCE

CROSS REFERENCES detailed cost data available (y/n) confidential information available (y/n)

GEODX REFNl

9.

REFERENCE

DATE OF ORIGINAL REPORT REPORTER(S)

Appendix 2. Report format for the Kidston deposit •

-- -

............. -

DEPOSIT:

12

-

_-_

__ .

KIDSTON

DEPOSIT IDENTIFICATION:

PRINCIPAL COMMODITIES: Au , Ag , MINES: Kidston , Wises Hill, OREBODIES: Kidston , Macks Knob, North Knob, Wises Hill, GROUP: Permo-Carboniferous Igneous Group COMMENTS: Includes regional setting of Permo-Carboniferous igneous group. See Deposit No.10 Georgetown for regional setting of Georgetown Inlier and Forsayth Subprovince.

LOCATION:

LATITUDE: 18 52 250K SHEET: SE55 9

LONGITUDE: 144 0 100K SHEET: 7760

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Georgetown MINING FIELD: Etheridge LOCALITY:

DEVELOPMENT HISTORY:

DISCOVERY YEAR 1907 1979 1979 1979

DISCOVERY METHOD Prospecting Geochemistry Dri II ing Geophysics

OPERATING STATUS AT 1987 MINE Kidston Kidston Wises Hill Kidston

STATUS Historical Operating Operating Historical

MINING METHOD Underground Open-Cut Open-Cut Alluvial

25

COMPANIES:

OREBODY: Kidston PRESENT OPERATORS: Kidston Gold Mines Ltd. PRESENT O\JNERS: Placer Pacific Pty Ltd.

EQUITY % 70

PRODUCT! ON:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE( t): 7,686,857

GOLD(kg) 16,016

RECOVERED GRADE(g/t) 2.08

COMMENTS

MAIN PRODUCTION PERIODS: (1907-1920) , (1910-1934) , 1985- ,

RESOURCES:

DATE

ORE('OOOt)

May 1987 39,402

GRADE(g/t)

GOLD(kg)

CLASSIFICATION

1.7

65,407

Economic Demonstrated Recoverable

PRE·MINE RESOURCE SIZE: M

GEOLOGY:

PROVINCE: BLOCK: PROVINCE: Georgetown Inlier SUB-PROVINCE: Forsayth Subprovince HOST ROCKS: Kidston Breccia Pipe Zoned monomictic, bimictic, and polymictic rhyolite breccia. Fragments and matrix are granodiorite, metamorphics, and rhyolite. Gold-sulphide mineralisation occurs in sheeted quartz-carbonate veins tangential to pipe margin and in quartz-carbonate breccia cavity infill cement. Butlers Volcanic Group Porphyritic rhyolite, rhyolitic ignimbrite. Butlers Volcanic Group and Lochaber Granite are the main units

26

of

the

Lochaber

o/c

Ring Complex. The ring complex is the source of the rhyolite dykes to which breccia pipe is genetically related.

the

Lochaber Granite Fine to medium biotite leucoadamellite with miarolitic cavities. See Butler Volcanic Group above. Oak River Granodiorite biotite granodiorite, Locally foliated medium porphyritic hornblende-biotite tonalite. Host to mineralised breccia pipe; contributes breccia fragments. Einasleigh Metamorphics Leucogranite, quartz-feldspar-biotite gneiss, minor amphibolite, gneiss, pegmatite, migmatite, and mica schist. Host to mineralised breccia pipe; contributes breccia fragments.

foliated

calc-silicate

AGE: Proterozoic Early STRUCTURAL FEATURES

STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact , IGNEOUS PROXIMITY MAJOR: Sub-Volcanism(Felsic Porphyry) , Volcanism(Felsic) , AGE OF INTRUSION: Palaeozoic Middle Carboniferous AGE OF INTRUSION: Palaeozoic Early Devonian AGE OF INTRUSION: Palaeozoic Late Silurian METAMORPHISM: Regional metamorphic grade is upper amphibolite facies. ALTERATION: Pervasive hydrothermal alteration is of restricted extent in the breccia pipe and outside the pipe is present only as haloes to sheeted veins. The rhyolite and adjacent breccias are within the zone of intense phyllic/argillic alteration. Granodiorite and rhyolite fragments are variably replaced by quartz, sericite, carbonate, pyrite and clay, and the breccia matrix is usually totally replaced. The intensity of alteration decreases away from the rhyolite breccia, grading into weak phyllic/propylitic alteration throughout most of the pipe.

DEPOSIT CHARACTERISTICS:

27

TYPES: Auriferous quartz veins in felsic volcanic breccia pipe. STYLE: Discordant, MORPHOLOGY: Pipe-Like, Sheeted , AGE OF MINERALISATION: Palaeozoic Middle Carboniferous DIMENSIONS: OREBODY: Wises Hill MIN STRIKE LENGTH TRUE WIDTH VERTI CAL DEPTH

AVE

m)

m) m)

MAX 650.0 350.0 300.0

NATURE OF MINERALISATION: Disseminated, Free Milling, Oxidised, Primary, PRIMARY ORE: Breccia , MINERALOGY: OREBODY: Kidston Sulphide ore (veins and infill): gold, pyrite, minor sphalerite, pyrrhotite, chalcopyrite, galena, arsenopyrite, molybdenite, tetrahedrite. Sulphides typically replace carbonate and comprise less than 5% by volume of the total rock. Native gold occurs as free microscopic particles with approximately 10% occurring in submicroscopic form in pyrite or arsenopyrite. Gangue (veins and infill): quartz, calcite, ankerite, epidote, adularia. GENETIC CONTROLS: The location of the breccia pipe is related to broad scale structural features and was apparently controlled by the same magmatic and post magmatic processes involved in the development of the ring complexes. Fluid inclusions: the stockwork quartz veins and tourmaline breccia yielded similar homogenisation temperatures of 320-460 deg, peak 420 deg, and 250-480 deg, peak 400 deg, respectively. Salinities for both displayed a bimodal distribution at < 10 equivalent weight % NaCl. Inclusions in the quartz breccia infill and sheeted veins yielded lower, similar homogenisation temperatures, of 172-388 deg, with maxima at 200 deg and 370, and 200-400 deg, maximum 260-300 deg, respectively. Salinities for both were < 10% NaCl. The fluid inclusion data indicate a depth of formation of < 2.5 km. GENETIC MODelS: Mustard (1986) proposed an epithermal model in which mineralisation and brecciation are directly related to massive release of volatiles from the apex of a crystallising felsic magma at shallow depth. i) Magmatic fluids were concentrated in a cupola of a major igneous mass and injected into the overlying rocks, forming quartz stockwork and tourmaline breccia. ii) Fluid overpressure resulted in development of unidirectional sol idification texture (lIbrain rock") in the apex of the cupola.

28

The fluid was a two phase fluid (250-480 deg, salinity 40-53% NaCI) coexisting with a gaseous fluid of low salinity (300-400 deg, 10% Nael). iii) Magma crystallisation was accompanied by increase in fluid pressure till fluids were violently released into the cover rock, forming the breccia pipe. iv) Late, cooler, mixed magmatic/meteoric fluids (200-400 deg, < 10% NaCI) were mobilised by the intrusion of rhyolite porphyry dykes and channelled through the breccias, depositing auriferous quartz-carbonatesulphide cavity infilling. Permeability was greatest in the rhyolite breccia around the pipe margin. v) Conical sheeted extension fractures were formed, possibly as a result of magmatic resurgence, and filled with precipitate from the same circulating fluids responsible for the breccia cement. GEOLOGICAL SETTING OF MINERALISATION: OREBOOY: Kidston REGIONAL SETTING: PERMO-CARBONIFEROUS IGNEOUS PROVINCE From the Late-Carboniferous'Early Permian much of north Queensland was the site of intrusion of granitic batholiths and eruption of extensive comagmatic volcanics. The magmatic activity was not influenced by previous tectonic boundaries and extended over the Cape York-Oriomo, Coen, Georgetown and Anakie Inliers, the Hodgkinson, Drumrnond and Burdekin Basins, and the Lolworth-Ravenswood Block. The intrusions range in size from small plutons and ring complexes to large batholiths, and are dominantly granite, adamellite, and granodiorite. The volcanics are dominantly rhyodacitic ash flow tuffs which occupy large cauldron subsidence areas. ASSOCIATED MINERALISATION Abundant gold mineralisation is associated with the Permo-Carboniferous igneous rocks. Historical production has come mainly from generally small but high grade vein deposits associated with granitic to dioritic plutons. Recent developments have been of bulk-tonnage low-grade disseminated orebodies associated with felsic volcanic and sub-volcanic complexes (e.g. Kidston, Pajingo, Mount Leyshon, Ravenswood, Far Fanning, Mount Success, Mount Yright, Lolworth, some Cape River). A second important type of lowgrade deposit is represented by the gold skarn mineralisation at Red Dome. GEOLOGICAL SETTING: KIDSTON Kidston lies in the south central-eastern part of the Forsayth Subprovince within a belt of abundant Late Palaeozoic igneous activity. Carboniferous felsic extrusive rocks (Newcastle Range Volcanics) cover a vast area northwest of Kidston and are rimmed by faults forming cauldron subsidence areas. The Kidston gold deposit is associated with a rhyolite breccia pipe which cuts the contact between Einasleigh Metamorphics and Oak River Granodiorite. The metamorphic/granite contact locally trends westnorthwest. The metamorphics comprise multiply deformed and folded schist, gneiss, amphibolite, migmatite and quartzite representing the oldest section of the metasedimentary sequence (Etheridge Group). The Oak River Granodiorite is a major phase of the Copperfield Batholith, a large

29

batholith of probable Siluro-Devonian age. In the deposit region it is intruded by a younger, marginal phase, the Digger Creek Granite. The regional granite/metamorphic contact in part forms the northerly extension of the Gilberton Fault, a major regional northeasterlystriking discontinuity which disrupts the overall northerly trend of the metasedimentary sequence to the north. South of the fault structural directions are dominantly northeast. The Einasleigh Metamorphics are intruded on the southern side of the Gilberton Fault by two major Carboniferous igneous complexes. The Lochaber Ring Complex and the Bagstowe Ring Dyke Complex comprise cores of adamellite or microadamellite surrounded by ring dykes of andesitic to rhyolitic composition. The complexes are elongate along collinear northeast axes. A rhyolite dyke swarm that emanates from the Lochaber Ring Complex intersects the Kidston breccia pipe. A gravity low follows the dyke swarm from the complex through the pipe, consistent with the possible presence of an igneous body at depth. Some of the rhyolite dykes cut the pipe margin, some are restricted to the pipe, and some have been brecciated. The Kidston breccia pipe is ovoid in plan with axial dimensions 1300 m X 920 m; the pipe is elongate in a north-easterly direction. Pipe margins dip inwards at 80 deg. The pipe comprises fragments of granodiorite, metamorphic rocks and rhyolite in a matrix of fine'grained « 1 mm) fragments of similar lithologies, and infilled by quartz-carbonate brecci a cement. The pipe is lithologically and structurally zoned, from the margin:i) outer zone: monomict (granodiorite or metamorphic rock) breccia reflecting country rock lithology; ii) inner zone: bimictic breccia, formed from mixing of rhyolite fragments with monomictic breccia; iii) central zone: polymictic breccia, formed from mixing of granodiorite, metamorphic and rhyolite fragments. Fragment size and fragment:matrix ratio decrease inwards as degree of mixing and vertical transportation increases. The outer zone is rimmed by a zone 10-20 m wide of shatter or crackle breccia in the country rock. The pipe is asymmetrical in zone development--the inner zone is best developed in the northeastern and southwestern sectors of the pipe. An area of rhyolite breccia occurs within the bimictic breccia in the southwestern sector and is broadly coincident with zones of pre-breccia features stock-work quartz veining, tourmaline breccia and "brain rock". The rhyolite breccia coincides with the maximum intensity of hydrothermal alteration. The pipe margin is overlapped by sets of tangential sheeted quartzcarbonate veins. The veins fill subparallel fractures which dip steeply into the pipe but at a shallower angle than the pipe margin. The veins average 10 mm in thickness and occur at a density of up to 10 per metre. The sheeted veins are also best developed in the southwest sector. Gold mineralisation occurs in association with sulphides which accompany quartz-carbonate in the sheeted veins and breccia cavity infill. Gold grades are generally higher in the veins than in the breccia infill. Cavity infill mineralisation is best deveLoped in the rhyolite breccias because of the higher permeability of rhyolite breccia and consequent higher proportion of hydrothermal matrix. The ore zones occur in a semi-continuous band near the margin of the pipe. Best ore development

30

is centred on the area of rhyolite breccia in the south west sector = Wises Hill, the site of current open cut mining.

REFERENCES:

Andrew A.S. ,Baker E.M. ,1987 The nature and origin of the ore· forming fluid in the Kidston gold deposit, north Queensland. IN Proceedings, Pacific Rim Congress 87, Gold Coast, Queensland, August 1987. AuslMM 1v P13·16 Bain J.H.C. ,Withnall I.W. ,1980 Mineral deposits of the Georgetown region, northeast .Queensland. IN Henderson R.A. & Stephenson P.J. (Eds)' The geology and geophysics of northeastern Australia. Geological Society of Australia. Queensland Division 1v P129·148 Baker E.M. ,1987 The geology, alteration and mineralisation of the Kidston breccia pipe. Ph.D thesis. James Cook University, North Queensland. Unpublished 1v Baker E.M. ,1987 Brecciation mineralization and alteration of the Kidston gold deposit. IN Proceedings, Pacific Rim Congress 87, Gold Coast, Queensland, August 1987. AuslMM 1v P29·33 Bartrllll J. ,Plyley W.F. ,1986 Some metallurgical aspects of the Kidston gold mine. IN Gold exploration and development, north Queensland. AuslMM Conference, Charters Towers, August 1986. Extended abstracts. AuslMM 1v P109-112 Branch C.D. ,1959 Progress report on Upper Palaeozoic intrusions controlled by ring fractures near Kidston, north Queensland. Bureau of Mineral Resources, Australia. Record 59/104 Branch C.D. ,1966 Volcanic cauldrons, ring complexes, and associated granites of the Georgetown Inlier, Queensland. Bureau Mineral Resources, Australia. Bulletin 76 Coldham J.C.

,1934

31

Report on the Oaks goldfield. Geological Survey of Queensland. CR 1022

Report

Grayl in R.K. ,1981 The geology of the Kidston breccia complex. M.Sc. thesis. James Cook University, North Queensland. Unpubl \shed 1v Jensen H.I. ,1920 The Kidston goldfield. Queensland Government Mining Journal 21 P186·192 Knight D.A. ,Medina V.G. ,1986 Kidston gold mine startup. Minerals and Metallurgical Processing 31(1) P45·49 Marks E.0. ,1911 The Oaks and eastern portion of the Etheridge goldfield. Geological Survey of Queensland. Publication 234 Mining Magazine. ,1986 Kidston gold mine, Australia. Mining Magazine 154(1) P16·21 Mustard H. ,1984 Brecciation and mineralisation at the Kidston gold deposit, north Queensland. IN Geoscience in the development of natural resources. Australian Geological Convention, Sydney 1984. Abstracts. Geological Society of Australia 12. (394·396 P394·396

7th

Mustard H. ,1986 Geology and genesis of the Kidston gold deposit, Queensland, Australia. IN Macdonald A.J.(ed) . Gold '86. Proceedings of symposium, Toronto, Canada, September'October 1986. Konsult International Inc., Yillowdale, Ontario, Canada 1v P404·415 Mustard H. ,1983 Breccia forming processes at the Kidston gold deposit. thesis. James Cook University, North Queensland. Unpublished 1v

B.Sc.(Hons)

Needham R. ,1985 The Kidston gold mine: a development challenge of a low grade deposit. IN AuslMM Annual Conference, Southern Queensland, Brisbane, July 1985. AusIMM. Conference Series 14 P121·128

32

Queensland Government Mining J , 1985 Kidston on stream: Queensland Premier opens Australia's biggest gold producer. Queensland Government Mining Journal 86(1001) P111-113 Rands W.H. , 1912 The Oaks Rush goldfield. Queensland Government Mining Journal 13 P544-548 Reid J.H. , 1932 The Oaks goldfield, Kidston. Queensland Government Mining Journal XXXIII P287-288 Turner A.R. , 1976 Geology and mineralisation of the Kidston breccia pipe, NE Queensland. Anaconda Australia Inc. Unpublished Report 1v Wilson G.I. , Lewis R.W. , Gallo J.B. , Tullemans F.J. , 1986 The geology of the Kidston gold mine. IN Berkman D.A.(ed) - 13th CMMI Congress, Singapore, May 1986. Publications Volume 2. Geology and exploration. 13th Congress of Council of Mining & Metallurgical Institutions &AusIMM 13(2) P235-242 Witson G. I. , 1987 The Kidston gold mine. IN Herbert H.K.(ed) - Gold in Queensland. Proceedings of one-day symposium, University of Queensland, June 1984. University of Queensland. Department of Geology. Papers 12(1) P84 Wilson G.I. , Lewis R.W. , Gallo J.B. , Tullemans F.J. , 1986 The geology of the Kidston gold mine. IN Berkman D.A.(ed) - 13th CMMI Congress, Singapore, May 1986. Publications Volume 2. Geology and exploration. 13th Congress of Council of Mining & Metallurgical Institutions & AusIMM 13(2) P235-242

0000000000000000000000000000000000000000

33

...---MICROGRAPHICS

BUREAU--------..-----------....

HORN ISLAND

DEPOSIT:

DEPOSIT IDENTIFICATION: PRINC IPAL COMflODITIES: AU , A9 , pb , zn , MINES: Ho rn Is land , ORE80DIES: Horn Is land , GROUP: Torres Strait Group COMMENTS: Includes regional setting of cape York-Or;omo Inlier and Torr'es Strait group. LOCATION: LA TITUDE: 10 36 250K SHEET: SC54 11

LONG nUDE: 142 19 100K SHEET: 7376

ADmNISTRATIVE SU8DIVISION: MINING DISTICT: Thursday Is land MINING FIELD: LOCALITY: DEVELOPMENT HISTORY: DISCOVEr
DISCOVERY YEAR 1894 OPERATING STATUS AT 1987 MINE Horn Horn Horn Horn

Is Is Is Is

land land land land

STATUS Hi stori ca l operati ng Hi stori ca l operati ng

MINING METHOD unde rg round Open-cut Alluvia l Alluv i a l

COMPANIES: ORE80DY: Horn Is land COMMENTS

PRESENT OPERATORS: Torres Strait Gold Pty Ltd. PRESENT OWNERS: Augo ld N L.

COMMENTS

EQUITY 731 .50

***

801

***

-AGPS--1Dd

pIIIIl l--MI CRO GRA PHIC S BURE AU ...- - -...- -.. .- - - - - - - - Giant Resourc es Ltd.

- -... ..

68.50

PRODUCTION: CUMULATIVE PRODUCTION (TO DEC.198 6): ORE(t): GOLD(kg) RECOVERED GRADE( 9/t) 16,904 208 12.28 MAIN PRODUCTION PERIODS: 1895-19 00 , 1987- ,

COMMENTS

RESOURCES: DATE

OrlE (' OOOt)

GRADE( g/t)

GOLD( kg)

CLASSIFICATION

Dec 1987 Dec 1987

2,120 360

2.3

4,833 324

Economi c Demons trated In-situ Economi c Demons trated Recover able - Measure d

0.9

o/c

a lv

Units are: ORE('OOO cubic m) GRADE( g/cubic m)

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: PROVINCE: C,\oe york-Ori omo Inlier SUB-PROV INCE: HOST ROCKS: Badu Grani te Equ;va lent porphy riti c mic rograni te. ~'ineralisation occurs in reefs consisti ng of sets of closely spaced quartz in altered si licified microgr anite.

veins

TorreS strai t Vo lcanics Rhyolit ic tuffs and flows, volcani c breccia , agglom Country rock to mineral ised microgr anite intruslo n. erate, andesit e, sedimen ts. Badu Granite Leucocr atic biotite granite , biotite- hornble nde granite and adamel lite. Mineral ised microgr anite is conside red to be late stage equival ent Gramte .

of

Badu

AGE: Palaeoz oic Carboni ferous STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS

1lIJBmm

***

c01

***

~-AGPS--rlIt II

plI!IlI-- MICROGRAPHICS BUREAU ---------------I!IlIJIII--1I!lIIIIlllIlII IGNEOUS PROXIMITY MAJOR: PlutonismCGranitel , AGE OF INTRUS ION: pa laeo zoi c Late Ca rboni fe rous METAMORPHIS M: The volcanics have been strong ly thermally metamorphosed over a wide contact aureole around the microgranite. Degree of metamorphism decreases westwards away from the intrusion. ALTERA TION: Mineralisation lies within a zone of pervasive hydrothermal alteration, which affected microgranite, felsic dykes and volcanics. Feldspar is replaced by clay. Zones of more intense alteration = fracturing, si licification, introduction of quartz vein networks and larger veins broadly relate to mineralised areas. Alteration is considered to be the result of late stage hydrothermal activity associated with emplacement of the porphyritic microgranite. DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. STYLE: Discordant, stratabound , AGE OF MINERALISATION: palaeozoic Late Carboni ferous DIMENS IONS: OREBODY: Horn Is land DEPTH OXIDATION

Cm l

~lIN

AVE

3.0

MAX

NATURE OF MINERALISATION: Free Mi lling , Oxidised, primary, RefractorY, PRIMARY ORE: stockwork , MINERALOGY: OREBODY: Horn Island sulIJhide zone: gold quartz, pyrite galena, +- spha lerite, chalcopyrite. Sulphides occur in the altered host rock. Because of the shallow depth of oxidation, most of the ore is in sulphides, which made treatment difficult and hindered development in the past. GENETIC CONTROLS: Controls are structural/lithological. GENETIC MODELS: Mineralisation was presumably introduced by late stage hydrothermal activity associated with intrusion oj high level microgranite. GEOLOGICAL'SETTING OF MINERALISATION: OREBODY: Horn Island Horn Island lies in Torres Strait close to the tip of CaIJe York Peninsula. Gold mineralisation occurs in quartz reefs within hydrothermally altered porphyritic microgranite which intrudes ignimbrites on

***

001

***

-- AGPS _ _=-lIlI

pma--MICROGRAPHICS BUREAU

~

s-.

IIIIIIlIIiII_..

the eastern side of the island. GEOLOGICAL SETTING: CAPE YORK-ORIOMO INLIER The main group of Torres strait is lands, which includes Horn Is land, represents the peaks of a submerged rid(3e of Carboniferous igneous rocks - the Cape York-Oriomo Ridge - wh1ch extends from Cape York Peninsula across the strait to Papua New Guinea. The ridge is made up of thick sheets of calc-aLkaline felsic welded tuft and subOrdinate Lavas intruded by Large bodies of probabLy comagmatic high level granite and porphyritic microgranite. The ii;lneous rocks are correlated with the permo-Carboni ferous volcanic/plutonlc province of north Queensland. The ridge is flanked by younger basin sediments. The volcanic ~equence Torres Strait Volcanics, consists of 300 m + of crystal-rich rhyolitic welded tuff and subordinate dacite or dellenite welded tuff, plus minor agglomerate( welded pumice-flow breccia, rhyolite, andesite, interbedded sed,ments. Four sets of ignimbrite sheets are distinguished on the basis of chemistry. The volcanic unit on Horn lsland is the Endeavour Strait Ignimbrite, 100 m + thick, and dipping shaLlowly to the northwest. Faulting between volcanic members Hay represent cauldron subsidence structures. The Torres Strait Volcanics are intruded and variably hornfelsed by high level granite, the Badu Granite( and porphyritic microgranite, plus associated felsic stocks and dYKes. On Ht>rn Island, the Endeavour Strait Ignimbrite is intruded by coarse porphyritic micro(3ranite considered to be a late stage equivalent of the Badu Granlte. Strong thermal metamorphism and hydrothermal alteration are associated with the intrusion. Mineralisation is hosted by reefs consisting of sets of closely-spaced quartz veins in silicified intensely altered microgranite.

=

REFERENCES: Willmott W.F. , Whitaker W.G. , palfreyman W.O. , Trail O.S. , 1973 Igneous and metamorphic rocks of Cape york Peninsula and Torres Strait. Bureau Mineral Resources, Australia. Bulletin

135

o~oooooooooooooooooooooooooooooooooooooo

...

*,H E01 ***

------------------~---~-AGPS--d

p!ZII-- MICROGRAPHIeS BUREAU -iIlIIIIIlIII-----------------1III!lIII DEPOSIT:

2

PALMER RIVER

DEPOSIT IDENTIFICATION:

SYNONYMS: May town , PaLmer , PRINCIPAL COMMODITIES: Au , MINES: Fiery Creek, paLmer River, PaLmervi LLe , Terrible Creek, OREBODIES: ALexander, Ida-Comet ,

Louisa ,

palmer River ,

~Jeen

,

GROUP: Hodgkinson Group COMMENTS: Inc Ludes regionaL setting of Hodgkinson basin and Hodgl:inson group. Record covers aLLuvial deposits distributed along paLmer River for 75km, and reef deposits occurring in an area of 30km2 east of May town. LOCATION: LONGITUDE: 144 20 100K SHEE·: 7865

LATITUDE: 16 1 250K SHEET: SE55 ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Cooktown MINING FIELD: palmer LOCALITY: DEVELOPMENT HISTORY:

DISCOVERY METHOD prospecti ng

DISCOV ERY YEAR 1873 OPERATING STATUS AT 1987 MINE Palmer River PaLI,/er River Pa lmervi Lle TerribLe Creek Fiery Creek

STATUS Histor Operat OPe rat Ope rat Operat

cal ng ng ng ng

~lINING METHOD ALLuviaL Al Luv i a L ALluv ia l AL Luvi a L Al Luv i a L

COMPANIES: OREBODY: paLmer River

,~**

FO 1

*,b~

....--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - . CO~lMENTS

PRESENT OPERATORS: C.L. Mine Management Ltd. City Resources Ltd. PRESENT OWNERS: City Asia City Resources Ltd. Leighton Resources Ptl' Ltd.

EQUITY 50.00 50.00 51.00

r.

COMMENTS

PRODUC TION: CUMULATIVE PRODUCTION (TO DEC.1986): ORECt):

~lAIN

GOLDCkg) 41,500

RECOVERED GRADECg/t) 0.00

CO~lMENTS

Ore tonnages and recovered grade not appLicabLe to a LLuv i a L c1epos i ts. Ze ro figures resuLt from program ca lcu Lati ons.

PRODUCTION PERIODS: 1873-1891 , 1982- ,

RESOURCES: PRE-MINE RESOURCE SIZE: M GEOLOGY: PROVINCE: BLOCK: Tasman FoLd BeLt PROVINCE: Hodgkinson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: Hodgkinson Formation si Ltstone, mudstone, plwLLite; interbedded with greywacke, arenite, and congLomerate; LocaL chert, Limestone, mafic voLcanics, rhyoLite. Main mineraLisation wa, .' ;haLLow aLLuviaL deposits in river sands. primary source was probabLy reef; in Hodgkinson Fm, in which ~oLd occurred in LenticuLar quartz-filLed fissures ~ repLacement veins in s ..eared dark phyLlite and greywac ke. AGE: paLaeozoic Early Carboni ferous AGE: pa Laeozoi c Mi dd Le Devoni an STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS

*,~*

G01 ***

- AGPS _ _1R1II!lI

...-~ MICROGRAPHICS

BUREAU--------------------a

IGNEOUS PROXIMITY METAMO RPHIS M:

Nil.

ALTERATION: DEPOSIT CHARACTERISTICS: TYPES:

~Ietamorphic

be Lt-type). ALLuv i aL.

auri ferous quartz veins in flysch-type metasediments (s Late

STYLE: Discordant, Stratabound , MORPHOLOGY: Lenti cuLa r , AGE OF MINERALISATION: Mesozoi c AGE OF MINERALISATION: paLaeozoic EarLy Carboni ferous DIMENS IONS: OREBODY: pa Lmer River TRUE WWTH

cm )

MIN

AVE

MAX 70.0

NATURE OF MINERALISATION: PRIMARY ORE: Vein (Reef) , SECONDARY ORE: DetritaL (ALLuviaL> , MINERALOGY: OREBODY: paLmer River suLphide ore: goLd, some pyrite, arsenopyrite, minor stibnite. SuLphides generaLLy Less abundant than at the Hodgkinson fieLd. Gangue: mi Lky vein quartz. GENETIC CONTROLS: The primary deposits of the Hodgkinson Basin Lie in a broad northnorthwesterly trending mineraLised zone which paraLLeLs the major regionaL structuraL trend. LocaL controLs are aLso structuraL in that the dominant reef strike is between north and northwest. Bends in the quartz veins were favourabLe Loci for ore enrichment. GENETIC MODELS: De Keyser & Lucas (1968) considered the goLd deposits of the Hodgkinson Basin to be mesothermaL, probabLy reLated to a permo-Carboni ferous granitoid source, which was postuLated to occur at depth b~neath the goLd mineraLisation. Gregory & others (1980) and Murray (1975) noted, however the regionaL absence of of any intrusive rocks and of contact metamorphism of the host sequence. Murray (1986) notes the simi Larity to the PaLaeozoic goLd sLate associations of Victoria. Gregory & others (1980) cited as a possibLe aLternative a voLcanogenic origin in which goLd was disseminated in a partlcuLar sedimentary facles following basaLtic eruption, and subsequentLy remobi Lised and concentrated in epigenetic quartz velns or carbonaceous horizons during foLding and metamorphism.

*,~*

H01

***

-AGPS--.-I

1I'J!lIIil!lIiI--MICROGRAPHIC8 B U R E A U - - - - - - - - - - - - - - - - - - - - - . De Keyser & Lucas (1968) attribute the greater abundance of alluvial goLd at Palmer River compared with the Hodgkinson fie ld to a greater depth of erosion at palmer River. GEOLOGICAL SETTING OF MINERALISATION: OREBOOY: Palmer River REGIONAL SETTING: HODGKINSON BASIN The marine Hodgkinson Basin developed in the Late Silurian alon9 the eastern margin of the Georgetown and Yambo Inliers. Sedimentat10n was controlled by a major fault zone - the Palmervi lle Fault - which formed a hinge Line between the Proterozoic rraton to the west and the rapidly subsiding depositiona l area to the east. More than 10 000 m of Si lurian and Devonian marine shelf and flysch-type oceanic slope and basin sediments accumu Lated over a basement whi c h p robab ly cons i sted at leas t partly of blocks of Proterozoic rock. The westernmost unit of the basin succession, the chi llagoe FQrmation, comprises carbonate-r;ch shelf sediments - limestone - interbedded with continental-s lope sed1ments - chert r quartzose and sublabi le arenite, siLtstone and conglomerate, with a nigh proportion of spi litic basalt showing pi llow structures, and minor fe lsic pyroc lastics. The formation has traditionally been interpreted (de Keyser & Lucas, 1968) as an unstable shelf deposit; however more recent work (Arnold & Fawckner, 1980) suggests that the formation represents a series of fault slices of sediments deposited in a variety of environments ranging from non-marine to moderately deep marine, cnd that the limestone lenses are allochthonous bloc~s down-faulted from a postulated shallow marine shelf to the west. The Chi llagoe Formation is host to gold mineralisation at Red Dome and Harpers in contact skarns associated with younger Palaeozoic intrusives (see Deposit No. 7 Red Dome). The main basin unit is the Hodgkinson Formation, a thick, extensive, uniform and poorLy fossiliferous geosynclinal flysch-type accumulation of rhythmically bedded arenites and lutites with intercalated beds of chert, felsic and mafic volcanics (spilite, andesite), and minor limestone. The lutites are micaceou~ quartz si ltstone, slaty mudstone, black phyllite. The arenites and coarser rocks are:i) massive, thick-bedded quartz-intermediate greywacke with apJJroximately equal proportions of feldspar and felsic to intermediate volcanic clasts; ii) intraformational greywacke conglomerate; and iii) fine to coarse thin-bedded quartzose arenites. Turbidite charateristics including grading, bottom structure, crosslamination and convolute lamination are best developed in the thinbedded greywackes. Volcanic and chert intercalations are most abundant in the southearn and western parts of the unit. Gold and gold-antimony mineralisation 1S concentrated in the same areas. The Hod9kinson Formation is highly folded but generalLy unmetamorphosed. The dom1nant regional structural trend is north-northwest to north, parallelling the basin axis and its western margin along the palmervi lle Fault. TWo main generations of foldin9 resulted in the present regional north-northwesterly strike and steep d1p. Large-scale faults, increasing in density towards the central part of the basin, trend north northwest in the south and north in the northern part of the basin. The flysch-type characteristics of the Hodgkinson Formation indicate deposition in a rapidly-subsiding basin and/or from detritus-laden currents under conditions ranging from turbidity current to slow pelagic. The basin floor was characterised by strong relief with deep marine troughs and steep ridges maintaining an appreciable bottom slope throughout most of the basin history. Flysch-type sedimentation conti nued at leas t into the Late Devoni an. Orogenic deformation began in the Late Devonian, possibly

**,~

101 ***

11lalIIsm---------------------~-AGPS--1IIlI!I

plIIII--MICROGRAPHICS

BVREAU--------------------.

contemporaneousLy with the closing stages of sedimentation. The basin floor hi9hs may have been the sites of magma generation prior to orogenesls. StabiLisation of the basin was compLeted with the intrusion of severaL Large, ovaL, post-orogenic granite plutons of Late Carbon)ferous age in tne central-west part of the basin, and the emplacement of multiple cauLdron subsidence ring complexes aLong the basin's southeastern mar9in. Because the eastern margin of the basin is not exposed, interpretatlon of its tectonic setting is equivocaL. possible proposed models are: i ) arc-trench gap assemblage associated with an Ar,dean-type continental margin volcanic arc on the precambrian craton to the west; iil accretionary prism formed in a subduction compLex; iii) back-arc modeL in which sequence accumulated in an incipient marginal sea which formed behind a voLcanic arc to the east; iv) rifted co~tinental margin. ASSOCIATED MINERALISATION The Hodgkinson Formation is host to widespread, diverse mineraLisation, inc luding tin, tungsten, antimony, moLybdenum, lead, si Lver, copper, fluorite. Some mineralisation formed syngeneticaLLy with the sediments and volcanics, most however, comprises veln deposits reLated to younger granitoids (of the Permo-Carboniferous voLcanic/plutonic province). The majority of primary goLd deposits occur in thin lenticuLar quartzfi Lled fissure and repLacement veins in the peLitic sediments, simiLar to the slate beLt goLd associations in Victoria. The deposits are concentrated in the centraL, western, and southern parts of the basin and aligned on northwest to north-northwest axes both on a regionaL and a locaL scaLe. REFERENCES: Adam N.A. , 1986 Mining and exploration on the PaLmer River. IN GoLd exp Loration and deveLopment, north QueensLand. AusIMM Conference, Charters Towers, August 1986. Extended abstracts. AusH1M 1v p34-36 ArnoLd G.O. , Fawckner J.F. , 1980 The Broken River and Hodgkir.son Provinces. IN Henderson R.A. & Stephenson p.J.(eds) - The geoLogy and geophysics of northeastern AustraLia. 3rd AustraLian GeologicaL Convention, TownsvilLe, 1978. Geological Society of AustraLia. Queensland Division 1v P175-189 Gregory p.W. , TayLor R.G. , White A.H. ,1980 MineraLisation in the Broken River and HodgKinson provinces. IN Henderson R.A. & Stephenson p.J.(eds) - GeoLo9Y and geophysics of northeastern AustraLia. 3rd Australian GeoLoglcaL Convention, Townsv i Lle, 1978. Geological Society of AustraLia 1v Jack R.L. , 1899 on a visit to the PaLmer goLdfieLd. Geo logica L Survey of Queens Land. pubLication 144 JensenH.I. ,1940 The paLmer River district.

-AGPS-----

llf!.'l!IB'I-- MICROGRAPHICS AeriaL, GeoLogicaL 45

BUREAU-------------------....

& GeophysicaL

Survey of Northern AustraLia.

QLd Repor

~1urray

C.G. , 1975 Tasman geosyncLine in QueensLand - mineraLization. IN Knight C.L.(ed) Economic geoLogy of AustraLia and Papua New Guinea - 1. MetaLs. AusIMM. ~lOnograph Series 5 p738-755 Murray C.G. , 1986 MetaLLogeny and tectonic deveLopment of the Tasman FoLd BeLt System in Queens Land. IN Scheibner E.(ed) - ~letaLLogeny and tectonic deveLopment of eastern AustraLia. ore GeoLogl' Reviews 1(2-4) P315-400 Queens Land. Department of Mine 1986 Queens Land mining historicaL coL{ection - PaLmer and the Normanby Rivers. Reproduction of fiistoricaL map, 1896. Queens Land. Department of ~Ii nes 1v Whitaker W.G. , 1975 Coen and Yambo InLiers - mineraLization. IN Knight C.L.(ed) - Economic geoLogy of AustraLia and Papua New Guinea - 1. ~letaLs. AusIMM. Monograph series 5 p518-521 de Keyser F. , Lucas K.G. , 1968 GeoLogy of the Hodgkinson and Laura Basins, north QueensLand. Bureau of MineraL Resources, AustraLia. BuLLetin 84 0000000000000000000000000000000000000000

emm

...

~

-AGPS &

U'III\I.~

MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - -'J, DEPOSIT:

3

FINE GOLD CREEK

DEPOSIT IDENTIFICATION: SYNONYMS: Groganvi LLe , Limestone Creek, PRINCIPAL COMMODITIES: AU , ~lINES

: AngLo-Saxon, Fine GoLd Creek,

OREBODIES: AngLo-Saxon, Fir.' GoLd Creek, GROUP: Hodgkinson Group COM~lENTS:

See Deposit No. 2 paLmer River for regionaL setting of Hodgkinson Basin and Hodg ki nson group. LOCATION: LONG nUDE: 144 23 100K SIlEET: 7765

LATITUDE: 16 21 250K SHEET: SE55 ADMINISTRATIVE SUBDIV IS ION: ~IINING DISTICT: Mareeba MINING FIELD: Chi LLagoe LOCALITY:

DEVELOPMENT HISTORY: DISCOVERY METHOD Prospec t i I1g

DISCOVERY YEAR 1886 OPERATING STATUS AT 1987 MINE AngLo-Saxon Fi ne GO Ld r ree k

STATUS HistoricaL Ope rati ng

MINING METHOD Unde r!l round ALLuv, a L

COMPANIES: OREBODY: Fine GoLd Creek COMMENTS

PRESENT OPERATORS: AustraLian Diversified Resources Ltd. PRESENT OWNERS:

EQUITY

r.

COM~'ENTS

***

L01

***

-AGPS--IIIIIIIII'I

piIIlIlII--MICROGRAPHICS

BUREAU-------------------1IIIIIIIl!

AustraLian Diversified Resources Ltd. Rimeki Pty Ltd.

75.00 25.00

Rimeki pty Ltd is wholly-owned by Solomon Resources N L.

PRODUCTION: CU~lULATIVE

PRODUCTION (TO DEC.1986):

ORE(t):

GOLD( kg) 1,092

RECOVERED GRADE(g/t) 0.00

COMMENTS Ore tonnages and rec\lvered Rrade not applicable to alluvial deposits. Zero figures result from program calculations.

MAIN PRODUCTION PERIODS: 1986- , RESOURCES:

---------ORE (' OOOt)

DATE

June 1987 4,600

GRADE(g/t)

GOLD(kg)

CLASS IFICA TION

0.6

2,760

Economic Demonstrated In-Situ - Measured

a lv

Economic Demonstrated In-Situ - Indicated Economic Demonstrated In-Situ - Indicated In-Situ Economi c Inferred

a lv

June 1987 3,400

0.4

1,428

June 1987 9,751

0.4

3,41 ?

June 1987 4,000

Units are: ORE('OOO cubi c metres) metre)

p'R~D~(H/cubic

a lv

a lv

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: 8LOCK: Tasman FoLd BeLl: PROVINCE: Hodgkinson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: Hodg ki nson Formati on Si Ltstone, mudstone, phyLLitei ,nter-bedded with greywacke, arenite, and cong lomerate; local chert, limestone, mafic volcanics, rhyoLite. Historically mined ore at Anglo"Saxon was in single wide fissure vein in Hodgkinson Formation. Current op'Hations are based on aLluvial deposits. AGE: palaeozoic Early carDoniferouc' AGE: pa laeozoi c ~Ii dd Le Devon; an STRUCTURAL FEATURES

fIIlIIIlIil-------~

***

N01

***

..,._...lliIn_Ai

~-AGPS --~

ms---

MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - r I I I I i 1 I I ! l !

MAJOR: FauLting, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY ~1ETAMORPHISM:

Nil.

DEPOSIT CHARACTERISTICS: TYPES: Metamorphic auri ferous quartz veins in fLysch-type metasediments (s Late be Lt-type). ALLuviaL. STYLE: Discordant , stratabound , MORPHOLOGY: LenticuLar, AGE OF MINERALISATION: Mesozoic AGE OF MINERALISATION: paLaeozoic EarLy Carboniferous DH1ENS IONS: OREBODY: Ang Lo-Saxon VERTICAL DEPTH TRUE WIDTH STRI'
m m m

MIN 100.0

AVE

MAX

200.0 2.0

133.0

NATURE OF MINERALISATION: PRIMARY ORE: Vein (Reef) , MINERALOGY: OREBODY: Fine GoLd cr~ek SuLphide ore: goLd, pyrite, arsenopyrite. ore became arsenicaL at depth. GEOLOGICAL SETTING OF MINERALISATION: OF'';BODY: Fine GoLd creek The deposit Lies near the western margin of the Hodgkinson Basin in an area of dense fauLting and strong shearing. Chert beds are common in the sedimentary sequence. REFERENCES: Gregory p.W. , TayLor R.G. , White A.H. (1980 Min~ralisation in the Broken River and HodgKinson provinces. IN Henderson R.A. & Stephenson p.J.(eds) - Geology and geophysics of northeastern Austr3lia. 3rd Australian Geologlcal Convention, Townsvi lle, 1978. Geological Society of Australia

***

N01

***

_..m---------------.......

..._ _ MICROGRAPHIeS BUREAU _ .... 1v

de Keys e r F. , Luc as K. G. , 1 968 GeoLogy of the Hodgkinson and Laura Basins, north Queens Land. BureaU of MineraL Resources, Australia. BuLLetin 84 0000000000000000000000000000000000000000

***

A02

***

-AGPS--1IIlIIIIII

~--MICROGRAPHICS BUREAU---....- - - - - - - - - - - - - - -..... DEPOSIT:

4

TREGOORA

DEPOSIT IDENTIFICATION: SYNONYMS: MitcheLL River, PRINCIPAL COMMODITIES: Au , Sb , Ag , MINES: BLack Knight, MitcheLL River, OREBODIES: BLack Knight, MitcheLL River, Tregoora , GROUP: Hodgkinson Group COrl~lENTS: See Deposit No. 2 palmer River for regionaL setting of Hodgkinson Basin and of H::>dg ki nson group.

LOCATION: LATITUDE: 16 35 250K SHEET: SE55 1

LONGITUDE: 144 33 100K SHEET: 7765

ADMINISTRATIVE SUBDIVISION: ~lINING DISTICT: ~lareeba MINING FIELD: ChiLLagoe LOCALITY:

DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1890 OPERATING STATUS AT 1987 MINE ~litcheLL River BLack Knight MitcheLL River

STATUS HistoricaL possible HistoricaL

MINING METHOD Underground Open-Cut . ALLuv i a L

COMPANIES: OREBODY: Black Knight PRESENT OPERATORS: Hawk Investments Ltd.

COMMENTS

,~** B02

***

-AGPS---JI

J!IIIRII--1UICROGRAPHICS

BUREAU----------------------.

PRESENT OWNERS: Hawk Investments Ltd. strategic Mi nera ls Corporation N L.

EQUITY 60.00 40.00

r.

COM~lENTS

PRODUCTION: MAIN PRODUCTION PERIODS: C1905-1914) , C1937-1944) , RESOURCES: DATE

OREC'OOOt)

GRADECg/t)

GOLDCkg)

CLASSIFICATION

Dec 1985

500

3.4

1,700

Sub-Econom i c Infe rred In-Si tu

olc

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: Tasman Fo ld Be It PROVINCE: Hodgki nson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: Hodgkinson Formation Siltstone, mudstone, phyllite; interbedded with greywacke, arenite, conglomerate; local chert, limestone, mafic volcanics, rhyolite. Gold/stibnite mineralisation is associated with a major shear zone.

and

AGE: Palaeozoic Early Carboniferous AGE: Palaeozoic Middle Devonian STRUCTURAL FEATURES MAJOR: Shearing SIGNIFICANT: Faulting, STRUCTURALlSTRATIGRAPHIC INTERS ECTIONS IGNEOUS PROXIMITY METAMORPHISM: Nil. ALTERATION: Nil. DEPOSIT CHARACTERISTICS:

,h~1,

C02

*** -AGPS--.....

1IfDIIII-- MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - I I I I I I I I I I TYPES: Metamorphic auri ferous quartz veins in flysch-type metasediments (s Late be Lt-type). STYLE: Discordant , stratabound , MORPHOLOGY: Lenti cu La r , AGE OF MINERALISATION: Mesozoic AGE OF MINERALISATION: PaLaeozoic EarLy Carboniferous DIMENSIONS: NATURE OF MINERALISATION: PRIMARY ORE: Vein (Reef) , MINERALOGY: OREBODY: MitcheLL River suLphide ore: goLd, stibnite, pyrite, arsenopyrite, sphaLerite, cha Lcopyrite. Gangue: quartz. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: MitcheLL River GoLd/stibnite mineraLisation is associated with a major shear zone. REFERENCES: ArnoLd G.O. , Fawckner J.F. ,1980 The Broken River and Hodgkinson Provinces. IN Henderson R.A. & Stephenson p.J .(eds) - The geoLogy and geophysics of northeastern AustraLia. 3rd AustraLian GeoLogicaL Convention, TownsviLLe, 1978. GeoLogicaL Society of AustraLia. QueensLand Division 1v p175-189 Gregory p.W. , TayLor R.G. , White A.H. (1980 MineraLisation in the Broken River and HodgKinson provinces. IN Henderson R.A. & Stephenson P.J .(eds) - GeoL0!ly and geophysics of northeastern AustraLia. 3rd AustraLian GeoLoglcaL Convention, TownsviLLe,1978. GeoLogicaL Society of AustraLia 1v Jack R.L. , 1884 Report on Hodg ki nson go Ldfi e Ld. GeoLogicaL Survey of Queens Land. 16

pubLication

Reisgys L. , 1986 Tregoora goLa project, north QueensLand. IN GoLd expLoration and deveLopment, north QueensLand. AusIMM Conference, Charters Towers, August 1986. Extended abstracts. AusIMM. North QueensLand Branch 1v p78-81

**,~

D02 ***

-AGPS-----

~--MICROGRAPHICS BUREAU-----~------~--.tIIjl---_.. de Keyser F. , Lucas K.G. , 1968 Geology of the Hodgkinson ana Laura Basins, north Queens land. Bureau of Mineral Resources, Australia. Bulletin 8/, 0000000000000000000000000000000000000000

,~**

EO 2

,~**

-AGPS---m

~-- MICROGRAPHIeS BUREAU-------------------~ DEPOSIT:

5

HODGKINSON

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: AU , sb , A9 , MINES: BeaconsfieLd , Hodgkinson, Northcote , Stuart Town, union, WoodviLLe , OREBODIES: BeaconsfieLd , FLying Pig, GeneraL Grant, Hodgkinson, Northcote , Southern Cross, Stuart Town, Thornborougn Union, Woodvi LLe

Kingsborough , Tyrconne L

GROUP: Hodgkinson Group COMMENTS: See Deposit No. 2 paLmer River for re9ionaL setting of Hodgkinson Basin and of Hodgkinson group. Record covers Hodgklnson fieLd = town area reefs + reefs in NW-trending be Lt 361an x 8km between Union in NW and Northcote in SE. LOCATION: LONGITUDE: 145 2 100K SHEET: 7964

LATITUDE: 16 56 250 K SHEET: SE55 ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Mareeba MINING FIELD: Chi l.Lagoe LOCALITY: DEVELOPMENl HISTORY:

DISCOVERY METHOD Prospecti ng

DISCOVERY YEAR 1875 OPERATING STATUS AT 1987 MINE BeaconsfieLd Hodgkinson Northcote Stuart Town union Woodvi LLe

STATUS HistoricaL HistoricaL HistoricaL HistoricaL HistoricaL HistoricaL

MINING 'lETHOD Unde rg round Unde rg round Unde rg round Underground Unde rg round Unde rg round

COMPANIES:

*** F02

**,~

a----------------------~-AGPS--

..

.,..--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - . PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t):

GOLD(kg)

RECOVERED GRADE(g/t)

300,000

9,330

31 .10

COM~lENTS

MAIN PRODUCTION PERIODS: 1875-1882 , RESOURCES:

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fold Belt PROV INCE: Hodgki nson-B roken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: Hodg ki nson Formati on Si ltstone, mudstone, phyllite; interbedded with greywacke, arenite, and cong lomerate; local chert, limestone, mafic volcanics, rhyolite. The main mineralisation was in lodes, and there was very little alluvial gold (in contrast to palmer River). The lodes consisted of sheared country rock interleaved with quartz stringers, or quartz veins. AGE: palaeozoic Early carboniferous AGE: palaeozoic Middle Devonian STRUCTURAL FEATURES MAJOR: Faulting, Shearing, S TRUCTURALlSTRA TIG RAPHIC INTERSECTIONS IGNEOUS PROXIMITY METAMORPHIS ~1:

Nil.

ALTERATION:

Nil.

DEPOSIT CHARACTERISTICS:

-----------------------TYPES:

.....

***

G02

***

[li]-AGPS--IIIIII

piIIIl_ _

MICROGRAPHIeS

BUREAU----------------------s

Metamorphic auriferous quartz veins in flysch-type metasedimcnts (slate be It-type). Alluvial. STYLE: Discordant, stratabound , MORPHOLOGY: Lenticular, AGE OF MINERALISATION: palaeozoic Early Carboni ferous DIMENS IONS: NATURE OF MINER,.,~ISATION: PRIMARY ORE: Lode (Alteration Zone) , Vein (Reef) , SECONDARY ORE: Detrital (ALluvial) MINERALOGY: OREBODY: Hodgki nson sulphide ore: gold, varying amounts of stibnite, some pyrite, arsenopyrite, minor chalcopyrite, sphalerite, galena; Locally rare molybdenite, some scheelite. The stibnite apparently belongs to a younger phase of hydrothermal activity. Gangue (slate): includes barite, tourmaline. GENETIC CONTROLS: The lodes lie within a structural zone controlLed by north-northwesterly trending faults. Local controls are also structural in that the dominant reef strike is between north and northwest. Bends in the quartz veins were favourable loci for ore enrichment. There is little evidence for stratigraphic control, except that occasionally carbonaceous slate formed a favourable host lithology (de Keyser & Lucas, 1968). GENETIC MODELS: In the intrusive mesothermal model (de Keyser & Lucas, 1968; see Deposit No. 2 palmer River), the Hodgkinson gold lodes are suggested as possibLy representing the upper zone of a zoned (tin) vein system, not yet suficiently eroded to provide substantial alluvial deposits as at palmer River. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Hodgki nson Hodgkinson occurs in the southern part of the Hodgkinson Basin, in a narrow densely fauLted neck. The mineralised area is bounded ol' 2 major north-north~lesterly trending fault zones. chert beds are common in the deposit region, abundant in the mineralised area. REFERENCES: Arnold G.O. , Fawckner J.F. , 1980 The Broken River and Hodgkinson Provinces. IN Henderson R.A. & Stephenson p.J.(eds) - The geology ~nd geophysics of northeastern Australia. 3rd Australian Geological Convention, Townsville, 1978. GeologicaL Society of Australia. Queensland Division 1v P175-189 Gregory P.W. , Taylor R.G. , White A.H. r 1980 Mineralisation in the Broken River and HodgKinson provinces. IN

"''''*

H02 'it.,.*

-AGPS-_ _d

...- - MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - . Henderson R.A. & Stephenson P.J .(eds) - GeoLogy and geophysics of northeastern AustraLia. 3rd AustraLian GeoLoglcaL Convention, TownsviLLe,1978. GeoLogicaL Society of AustraLia 1v Jack R.L. , 1884 Report on Hodgkinson goLdfieLd. GeoL/)gicaL Survey of Queens Land. 16

pubLication

de Keyser F. , Lucas K.G. , 1968 GeoLogy of the Hodgkinson and Laura Basins, north Queens Land. Bureau of ~'ineraL Resources, AustraLia. BulLetin 84 0000000000000000000000000000000000000000

***

r02

***

-AGPS--....

1ilJ!llIl!lII--MICROGRAPHICS DEPOSIT:

6

BUREAU---------------------.

BELFAST HILL

DEPOSIT IDENTIFICATION: SYNONYMS: Be Lfast , PRINCIPAL COMMODITIES: AU , sb , Ag , AS , MINES: BeLfast HiLL, OREBODIES: BeLfast Flat, Belfast Hi LL, Limerick HiLL West,

Limerick

Hi LL

Limerick

Hi LL

East

GROUP: Hodg ki nson Group COM~lENTS:

See Deposit No. 2 PaLmer River for regional setting of Hodgkinson Basin and Hodg ki nson group. LOCATION: LA TITUDE: 17 2 250 K SHEET: SE55 5

LONGITUDE: 145 12 100K SHEET: 7963

ADMINISTRATIVE SUBDIVISION: ~lINING DISTICT: ~'a reeba MINING FIELD: Chi LLagoe LOCALITY:

DEVELOPMENT HISTORY: DISCOVERY METHOD Geochemistry DrilLing GeoLogy. GeophysHs

DISCOVERY YEAR 1984 1984 19l>'+ 1984 OPERATING STATUS AT 1987 MINE BeLfast Hi LL

STATUS possibLe

mNING METHOD Open-Cut

CO~lPANIES:

OREBODY: BeLfast Hi LL PRESENT OPERATORS:

CO~'MENTS

-AGPS--.-B

pm--

MICROGRAPHICS

:DUREAU------------------·

l --.

North Queens Land Resources N L. PRESENT OWNERS: CentraL ~lining Corporation N L. North Queens land Resources N L.

CO~lMENTS

EQUITY "

35.00 65.00

PRODUCTION:

MAIN PRODUCTION PERIODS: - , RESOURCES: DATE

OREC'OOOt)

GRADECg/t)

GOLDCkg)

CLASSIFICATION

Dec 1 987

244

1.5

366

Sub-Economic Inferred In-Situ

o/c

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: Tasman FoLd BeLt PROVINCE: Hodgkinson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: Hodgki nson Formation si Ltstone, mudstone, phyLLite; interbedded with greywacke, arenite, and congLomerate; LocaL chert, Limestone, maiic voLcanics, rhyoLite. MineraLisation comprises quartz stockworks and fissure fi LLings aLong a northl4est-trending structura L zone. AGE: paLaeozoic EarLy Carboniferous AGE: pa Laeozoi c Mi dd Le Devoni an STRUCTURAL FEATURES MAJOR: Shearing, SIGNIFICANT: FauLting STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXH1ITY METM10RPHIS~1:

Nil.

DEPOSIT CHARACTERISTICS:

,~**

KO 2

,~**

r...----------------------[[jiJij-AGPS ---'

. . - - - MICROGRAPHIeS BUREAU .1~~·_------_1II_----------1Illll TYPES: Metamorphic auriferous quartz veins ill fly,·ch-type metasediments (slate be It-type). Alluv i a l. STYLE: 7 , Discordant , ~10RPHOLOGY:

strata~ound

,

Lenti cu Lar ,

AGE OF MINERALISATION: Palaeozoic Early Carboniferous DIMENS IONS: NATURE OF MINERALISATION: PRIMARY ORE: Vein (Reef) , MINERALOGY: GENETIC CONTROLS: controls are both structural and lithological. Mineralisation is localised in structural zones and in the permissive, brittle-fracturing finer grained carbonaceous sediments along and crossing the structures. GENETIC MODELS: The structures are considered to be hydrothermal feeders for the introduction of Au, As, and sb in a chlorite or thiosulphate-bearing low-temperature aqueous medium high in the epithermal system. The low base-metal, Mo, and W levels in the mineralised rocks indicate that the gold-bearing zones lie well above the chloride dominated hotter re~ions of the classic hydrothermal system. The absence of chaLcedonic velning and low Ba leveLs indicate a vertical zonal position be Low the uppermost zone of that system. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Belfast Hi Ll Belfast HiLL OCCU-q near the southern margin of the Hodgkinson 8asin, south along strike from Hodgkinson, in an area of dense faulting. Cherts lenses are crmmon in the host metasediments. Some of the largest of the permo-CarboniferCJus ring complexes lie to the south of the deposit region. The prospects are a suite of quartz stockwork and fissure fi llings occurring along a northwest trending suture over a length of more than 5 km. Gold mineralisation is related to locally brecciated shear zones which frequentl',·cross cut bedding and may represent mineralisation in di lational Ilrench faults. One zones are apparently Localised in a series of en echelon, p lunging pinch and swell structures within the shear zones. REFERENCES: Gregory p.\~. , Taylor R.G. Mine'·" 'isation in the Broken Hend",,-,on R.A. & Stephenson nort:reastern Austra l i a. 3rd Townsv i lle, 1978.

, Whi te A.H. (1980 River ilnd HodgKinson provinces. IN P.J.(eds) - Geolo~y and geophysics of Australian Geologlcal Convention,

-AGPS--..."

,---"MICROGRAPHICS BUREAU .-..- - - - . - - - - - - - - - - - - - -.... GeoLogicaL Society of AustraLia 1v Jack R. L. , 1884 Report en Hodgkinson goLdfieLd. Geo Logi ca L Survey 0'" «ueens Land. 16

publi cation

de Keyser F. , Luca5 K.G. , 1968 GeoLogy of the Hodgkin'''In and Laura Basins, north QueensLand. Bureau of MineraL Reso~,ces, AustraLia. BuLLetin 84 0000000000000000000000000000000000000000

*,~*

1'102 ***

..

-

-AGPS---III

....- - MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - - - - - . DEPOSIT:

7

DO~lE

RED

DEPOS IT IDENTIFICATION:

SYNONYMS:

~ngana

,

PRINCIPAL COMMODITIES: Au ,

Ag , Cu ,

Zn ,

MINES: Red Dome, OREBODIES: Red Dome , GROUP: permo-Carboniferous Igneous Group COMMENTS: Inc ludes regionaL setting of Permo-Carboniferous igneous group. 2 paLmer River for regional setting of Hodgkinson Basin.

See Deposit No.

LOCATION: LATITUDE: 17 6 250K SHEET: SE55 5

LONGITUDE: 144 24 100K SHEET: 7763

ADMINISTRATIVE SUBDIV IS ION: MINING DISTICT: Mareeba MINING FIELD: Chi llagoe LOCALITY: DEVELOPMENT HIST:RY: DISCOV ERY METHOD Geochemistry Dri lling Geology Geophysics

DISCOVERY YEAR 1981 1981 1981 1981 OPERATING STATUS AT 1987 MINE Red Dome Red Dome

STATUS Operati ng Operati ng

MINING METHOD Heap-Leach Open-Cut

COMPANIES: ORE80DY: Red Dome COMMENTS

PRESENT OPERATORS:

***

N02

*** -AGPS~-""

1iSIfJI-- MICROGRAPHIeS BUREAU

BIIIIl!-...

Elders Resources Ltd. EQUITY 100.00

PRESENT OWNERS: Elders Resources Ltd.

r.

COMMENTS

PRODUCTION: CUMULATIVE PRODUCTION (TO DECo1986): ORE(t):

GOLD(kg) 213

RECOVERED GRADE(g/t) 0.00

COMMENTS Ore tonnagen and recovered grade not applicable to alluvial deposits. ~~ro figures result from program calculations.

MAIN PRODUCTION PERIODS: - , 1986- , RESOURCES:

---------DATE

ORE(' OOOt)

GRADE(g/t)

GOLD(kg)

CLASS IFICA TION

Dec 1987

2,800

2.5

7,000

Dec 1987

3,100

2.3

7,130

2.2

11,440

Economic Demonstrated Recoverable - Measured Economic Demonstrated In-Situ - Measured Economic Demonstrated In-Situ - Indicated

Dec 1987

5,200

olc

suitable for heap-leach treatment Copper oxide ore

olc

su lp hi de ore

olc

PRE-MINE RESOURCE SIZE: M GEOLOGY: PROV INCE: BLOCK: Tasman Fold Belt PROVINCE: Hodgkinson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: chi llagoe Formation lithic si ltstone, and Limestone, sublabi le quartzofeldspathic arenite conglomerate, chert, mafic volcanics, felsic tuft. Host to primary gold mineralisation in woLLastonite-garnet skarn formed by metasomatic alteration of limestone adjacent~to rhyolitic porphyry dykes. Nested Rhyolite porphyry Zoned rhyolitic quartz-feldspar porpl,yry. rmati on 0 fear ly metasomati c Source of the hydrothermal system which caused foaltered to wollastonite-garnet skarns which were subsequently preferentially Nested Porphyry. skarn, predominantly in the aoical zones of the Crowded porphyry Dikes

....

***

A03

***

..-z....~ ~ - ~ ~ - A G P S - - a I

.---MICROGRAPHICS BUREAU

~

II!IIIIB

"'"

RhyoLitic quartz-feLdspar porphyry. Source of hydrothermaL system which caused formation of the woLLastonite-garnet skarn which was prefrentiaLLy replaced by green ga~net-bornite skarn which carries the primary goLd mineraLisation. Karst-coLlapse breccia. contains a major proportion of the ore in oxide mineralisation in skarn fragments and matrix materiaL. AGE: pa Laeozoi c Ear Ly Devoni an AGE: paLaeozoic Late Si lurian STRUCTURAL FEATURES MAJOR: shearing, STRUCTURALlSTRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive contact, IGNEOUS pROXIMITY MAJOR: sub-Volcanism(Felsic Porphyry) , AGE OF INTRUSION: paLaeozoic Late Permian AGE OF INTRUSION: paLaeozoic Early carboni fHous METAMORPHISM: Regiona l metamorphism ni l. ALTERATION: The host sedimentary-volcanic sequence has been affected by a compLex prograde-retrograde thermaL metamorphic history, dominated by sequential skarn formation, as a resuLt of muLtip le igneous intrusion. Three main paragenetic stages can be recognised: metamorphism, metasomatism and retrogression. The two Later stages can be further subdivided into early and late events. GoLd mineraLisation was introduced at the earLy retrograde stage of metamorphism. i) Contact metamorphic stage:- intrusion of Nested RhyoLite porphyrl' into a major structuraL discontinuity caused earLy formation of biotite and tremolite hornfels and bleached c linopyroxene-garnet rock in noncarbonate lithoLogies, and banded skarn in interbedded marbLe/noncarbonate hosts. Clinopyroxene skarn repLaces quartzofeldspathic sandstone, wollastonite-garnet-vesuvianite skarn replaces chert, and cLinopyroxene-sphene skarn repLaces andesite. ii) Early metasomatic stage:- extensive Fe-si-Ca metasomatism of host and intrusive rocks occurred concomitantLy with expulsion of fLuids from the Nested RhyoLite porphyry. TWo types of skarn were produced: green andradite garnet-magnetite skarn replaced marble along contacts with NRP and at other LithoLogical contacts near porphyry (exoskarn); and hedenbergite cLinoPl'roxene skarn replaced quartz and aLkali feLdspar within the NRP, preferentiaLLy repLacing the quartz stockwork (endoskarn). iii) Late metasomatic stage:- intrusion of the Crowded porphyry Dikes caused the formation of woLL
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _*** _803 _ ,~** _

~

~-AGPS--~

...

....- - MICROGRAPHIeS BUR;dAU--~----------------iv) EarLy retrograde stage:- circuLation and reaction of resi~uaL magm<;tic fluids with cooLer fluids, possibLy meteori.c :]ro 'ndw3ter, resuLted in precipitation of green andradite garnE't ~nd associated bornite-dominated Cu-Au-Ag ore. The green garnet- . ~r~ite skarn occurs preferentiaLl)' as repLacement of woLLastonite-~arnet skar r ., al'd aLso as repLacement of cLinopyroxene and garnet-magnetite sr.arns, porphyry and marbLe, and as veins within Rorphyry_ v) Late retrograde stage:- with coLLapse and further cooLing of the hydrotherma L system, meteori c waters penetrated the core of the NRP and produced extensive hydrosi Li cate aLteration of green garnet skarn and intrusive rocks. Carbonate-quartz-sericite aLteration assembLage formed in association with Cu-Pb-Zn-Ag mi ne ra Li sati on. DEPOSIT CHARACTERISTICS: TYPES: caLc-si Licate skarn adjacent to feLsic/intermediate porphyry intrusive. Skarn breccia/quartz stockwork adjacent to feLsic/intermediate porphyry intrusive. STYLE: Discordant , stratabound , MORPHOLOGY: IrreguLar, pipe-Like, AGE OF MINERALISATION: Mesozoic cretaceous AGE OF MINERALISATION: paLaeozoic Late permian AGE OF MINERALISATION: paLaeozoic EarLy Carboniferous DIMENS IONS: OREBODY: Red Dome DEPTH OXIDATION STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH

m

m m m

mN

200.0 100.0

AVE

MAX

250.0 100.0 350.0

NATURE OF MINERALISATION: oxidised, primary, PRIMARY ORE: Skarn , SECONOARY ORE: Breccia , MINERALOGY: OREBODY: Red Dome suLphide ore: The most important host of goLd is the copper-goLd-siLver ore. suLphide ore: bornite, chaLcocite, sphaLerite, magnetite, Lead-goLdsilver teLlurides (aLtaite, hessite, syLvanite, ~etzite), wittichenite (Cu-BisuLphide). The te Llurides occur as fine (5-25 microns) inc Lusions within the other suLphide phases. No free goLd in the primary ore. The Cu-Au-Ag ore is preferentiaLLy hosted b)' woLLastonite-garnet skarn (60-70% of totaL Rrimary ore), associated with green garnet, quartz, caLcite and fLuorite. This ore aLso occurs within magnetite skarns, again associated with green garnet; here bornite aLters to chaLcopyrite rather than chaLcocite. Ore mineraLs aLso occur where green garnet skarn cuts across earLier formed massive andradite and hedenbergite in

-AGPS--......

fI!IBI!I--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - - - . veins, and economic concentrations of gold and si lver occur within quartz stockwork veins which have been overprinted by hedenbergite, wollastonite-garnet and green garnet skarns. Oxidised ore: malachito, quartz, chrysocolla, copper, calcite, free gold. Gangue: kao l i ni te, !iJarnet, magnetite. Copper-only mineral1sation is either associated with amphibole-epidote alteration of garnet-magnetite skarn, or occurs where green andradite garnet replaces intrusive rocks rather than pre-existing skarn. Later copper-lead-zi nc-si lver mi ne ra lis ati on occurred contemporaneous with strong carbonate-quartz-seric ite a lte ration of IJre-exi sti ng s karns and intrusive rocks. copper-only and copper-lead-zinc-si lver minera lisation are devoid of goLd. GENETIC CONTROLS: Cont ro Ls are c hemi ca L/ litho Log i ca Land s tructu ra L. ChemicaL/lithoLogicaL:- the introduction of fLuid-saturated magma with favourabLe chemistry and high ore-metaL content into reactive carbonate LithoLo!iJy triggered a series of a Lteration reactions Leading to gold deposit10n in favourabLe woLLastonite-garnet skarn LithoL0!iJY. Fluid inc Lusion studies (Torrey, 1986) suggest a sequential evoLution of fluids, from earLy high temperature (250 aeg C - 520 deg C)/high saLinity (35-60 wt r. NaC L eguivaLent) fluids to Later Low to moderate temperature (200 deg C - 375 deg C)/Low saLinity (2-8 wt r. NaCl equivaLent) fLuids. StructuraL:- the Nested RhyoLite porphyry trends northwest, paraLLel to major regional faults. The faults are part of a major shear zone which extends both southeast and northwest from the deposit. The shear is steepLy dipping and considered responsible for the localisation of the intrusions and the karst-collapse breccia. GENETIC MODELS: Torrey (1986) proposed a fluid model in which sequential development of skarn and mineralisation 1S corre lated with intrusive history. [See Alteration: paragraphs i) - v) of the model correspond to the alteration stages i) - v)]. i) Contact metamorphic skarns formed by isochemical di ffusion between carbonate and non-carbonate rocks in the early stages of intrusion. ii) Moderate to high temperature/high salinity magmatic fluids transported Fe and Si into marble to produce garnet-magnetite exoskarn. Convective recirculation transported Ca into the intrusion to form clinopyroxene endoskarn. osci llatory emplacement of quartz stockwork, garnet-magnetite The Crowded porphyry Dikes were either the source of wollastonite!iJarnet skarn-forming fluids or triggered the re lease of residual fluids 1n the NRP. These fluids were rich in HCl. After repLacement of early metasomatic skarns, the fluid was rich in H20, Si02, and iron ch lori de comp le xes. iv) Reaction of the Fe-rich, oxidising residuaL magmatic fluid (homogenisation temperature 350 deg C - 380 de!iJ C, salinity < 10 wt r. NaCl equivalent) with cooler, lower salinity c1rculating external fluids ? = meteoric ground water, resulted in formation of green garnet and Cu-Au-Ag sulphi de mi nera l i sati on. v) Cool (200 deg C), low salinity meteoric water penetrated the core of the Nested Rhyolite porphyry, causing extensive late retrograde a lte rati on. vi) Upli ft, erosion and decomposition of sulphides caused the formation of a highLy oxidised karst-collapse breccia. The Red Dome breccia is considered to have formed by dissolution of marble and collapse of wall and roof rocks. This occurs predominantly

...

*,~*

DO 3

,~** ~-AGPS--1IlI!I

....--MICROGRAPHICS

BUREAU---------------------.

around porphyry dykes where skarn has formed. Reaction of sulphides in the skarn with percolating ground water caused acid solutions to form. These in turn induced preferential dissolution of marble and strong oxidation of non-carbonate rocks, leading to collapse and formation of residuaL garnet sand. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Red Dome REGIONAL SETTI~G: HODGKINSON BASIN/PERMO-CARBONIFEROUS IGNEOUS GROUP Red Dome lies in the western part of the Hodgkinson Basin within 1 km of a major fauLt, the Palmerville Fault, which separates the SiluroDevonian basin sequence to the east from proterozoic rocks of the Geor!3etown Inlier to the west. Both provinces are intruded by gran1toids and overLain by rhyolitic and rhyodacitic volcanics of the Permo-Carboni ferous volcanic/p lutonic province. The deposit occurs in carbonate-rich facies, the chi llagoe Formation, which represents the earLy unstabLe sheLf stage of basin sedimentation. The ChiLlagoe Formation consists of steeply-dlpping, northwest-striking subLabi Le quartzofeLdspathic arenite and si Ltstone, chert, limestone, intraformationaL Lithic conglomerate, and mafic volcanics. The Precambrian rocks consist of amphiboLite, schist and gneiss of the Ethe ri dge Group. GEOLOGICAL SETTING: RED DOME Red Dome lies within a major steeply-dipping, northwest-trending shear zone and the deposit is cut into four blocks by steeply-dipping, north to north northeast-trending faults. A central downthrown block contains much of the goLd ore. The deposit occurs between quartzofeldspathic sandstone and chert LocaLLy containing c~rbonaceous material to the south, and andesite, Lithic congLomerate, and Limestone, to the north. Limestone is metamorphosed to marble c lose to intrusives, and much of the marbLe is wholly or partly replaced by garnet skarn. Gold mineraLisation is associated with copper and si lver mineralisation in wo llastoni te-garnet s ka rn at the contact between a zoned porp hy rY intrusive, the Nested Rhyolite porphyry (NRP), and marbLe. Mineralised skarn is concentrated in the apical part of the NRP. The NRP disp lays crenuLate quartz Layers ("brainrock texture"), micrographic intergrowths, miaroLitic cavities, and crude pi lotaxitic texture, and carries quartz stockworks which commonLy pervade the country rock. These features are considered to indicate crystalLisation from a water and/or volati Le saturated magma. The woLLastonite-garnet skarn was originally barren, and post-dates crystaLLisation of the NRP. It replaces pre-existing garnet-magnetite and c linopyroxene skarns and is considered to be reLated to a Later, volumetrically insignificant, porphyry dyke system, the Crowded porphyry Dikes (CPD). The CPD do not have the features of the NRP cited as indicative of a fluid saturated magma. Oxidised ore occurs in a younger (?Cretaceous) karst-coLlapse breccia in the upper leveL of the deposit. Breccia fragments are quartzofeLdspathic sandstone, chert( andesite, porphyry, auriferous skarn, jasperoidal siLica, rare marole. Matrix 1S limoni'tic, hematitic or chloritic mud or muddY sandstone with garnet sand. The breccia is rimmed by zones of intense 14alLrock fracturing and oxidation. REFERENCES: Broadhllrst E. , 1952 The geoLogy of the Mungana-Redcap area, Chi llagoe district.

a...

***

E03 ,~**

l[iij_AGPS--Id

....--MICROGRAPHICS BUREAl,.T - - - - - - - - - - - - - - - - - - - - - - . Aus IMEng. P roceedi ngs 164 /165 PS-3D Christie M.A. , Erceg M.M. , 1986 Red Dome - Large scaLe heap Leaching. IN GoLd Exp Loration and deveLopment, north Queens Land. AusIMM Conference, Charters Towers, August 1986. Extended abstracts. AusIMM. North QueensLand Branch 1v P13-15 Co LLins S. , 1 987 The geojJhysics of the Red Dome goLd mine and surrounding areas. IN AustraLian society of ExpLoration Geophysicists. 5th GeophysicaL Conference and Exhibi<;ion, perth, February 1987. Extended abstracts. Exp Loration Geophysics 18(1/2) P19-2D Joyce P.J. , KarjaLainen H. , Johnson L. 1987 The geoLogy of the Red Dome deposit. IN Herbert H.K.(ed) - GoLd in QueensLand. proceedings of one-daY symposium, university of QueensLand, June 1984. University of Queens Land. Department of GeoLogy. Papers 12(1) P1DO-109 Matthews W.E. , Timms P.D. , 1984 The Mungana Red Dome deposit. IN Geoscience in the deveLopment of naturaL resources. 7th AustraLian GeoLogicaL Convention, sydney 1984. Abstracts. GeoLogicaL Society of AustraLia 12 P363-364 Reid J .H. , 1932 Mount Wandoo goLd mine, Mungana district. QueensLand Government Mining JournaL XXXIII P164-167 Smith J. , 1985 A mineraLised soLution collapse breccia, Red Dome, Mungana, North QueensLand. B.sc.(Hons) thesis. James Cook University, North QueensLand. UnpubLished 1v Torrey C.E. , Karj a Lainen H. , Erceg M. , Joyce P.J. , Stevens M. 1986 GeoLogy and mineraLi zation of the Red Dome Olungana) goLd skarn deposit, north Queenstand, AustraLia. IN Macdc·naLd A.J.(ed) - GoLd '86. proceedings of symposium, Toronto, Canada, september-October 1986. KonsuLt InternationaL Inc., WiLLowdaLe, ontario, Canada 1v p5D4-517 Torrey C.E. , KarjaLainen H. , Joyce P.J. , Erceg M. , stevens M. 1986 GeoLogy and mineraLisation of the Red Dome (Mungana) goLd skarn deposit, north QueensLand, AustraLia. James Cook University, North QueensLand. Economic GeoLogy Research Unit. 21 Torrey C.E. , 1986 GeoLogy and genesis of the Red Dome nlungana) goLd skarn deposit, north QueensLand. M.SC. thesis. J ames Cook Unive rs i ty, No rth Queens Land

....

**,~

FD3

*,~,~

I[iiJlI_AGPS--..

. - - - MICROGRAPHICS

BUREAU---------------------.

1v

de Keyse~ F. , BayLy M.B. , WoLff K. , 1959 The geoLogy and mineral deposits of the Mungana, chi llagoe, and Almaden 1-mi le Sheets, north Queens Land (Part 1). Bureau of MineraL Resources, Australia. Record 59/108 0000000000000000000000000000000000000000

,~**

G03

***

.---M ICR OGR APH ICS BUR EAU - - - - - - ------------DEPOSIT:

8

-.

HARPERS

DEPOSIT IDENTIF ICATION : SYNONnlS: Fluorsp ar, PRINCIP AL COMMODITIES: AU , A9 , MINES: OREBODIES: Harpers , GROUP: Permo-C arboni ferous Igneous Group COMMENTS: See Deposit No. 2 palmer River for regiona l settin~ of Hodgkin son Basin; Deposit No. 7 Red Dome for setting of Permo-C arbonife rous 19neous group. LOCATION: LATITUDE: 17 17 250K SHEET: SE55 5

LONGITUDE: 14435 100K SHEET: 7863

ADMINISTRATIVE SUBDIVI SION: MINING DISTICT : Mareeba MINING FIELD: Chi llagoe LOCALITY: DEVELOPMENT HISTORY: DISCOVERY YEAR 1987 1987 1987 1987

DISCOVERY METHOD Geochem istry Drilling Geo logy Geophys ics

OPERATING STATUS AT 1987

COMPANIES: OREBODY: Harpers PRESENT OPERATORS: E lde rs Resourc es Ltd. PRESENT OWNERS: Elders Resourc es Ltd.

......

_~

COMMENTS EQUITY 100.00

r.

CO~l~1ENTS

IJlji j_A GP S-_ d

BUREAU-·-------------------..

~--MICROGRAPHICS PRODUCTION:

MAIN PRODUCTION PERIODS: -

,

RESOURCES: DATE

OREC'OOOt)

GRADE(g/t)

GOLDCkg)

CLASSIFICATION

Aug 1986

830

1.9

1,577

Sub-Economic Inferred In-Situ

o/c

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman FoLd BeLt PROVINCE: Hodgkinson-Broken River Orogen SUB-PROVINCE: Hodgkinson Basin HOST ROCKS: ELizabeth Creek Granite Granodiorite. Intrudes host sediments in deposit area. ChiLLa~oe Formation subLabl Le areni te, si Ltstone, tuft.

Limestone, basa Lt, chert, quartzose areni te,

fe Lsic

EL i zabeth Cree k Grani te Granodiori te. AGE: paLaeozoic EarLy Devonian AGE: palaeozoic Late Si Lurian STRUCTURAL FEATURES STRUCTURALlSTRA TIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, IGNEOUS PROXH1ITY MAJOR: pLutonismCGranite) , AGE OF INTRUSION: paLaeozoic permian AGE OF INTRUSION: palaeozoic Carboniferous ~lETAMQRPHISM:

Nl L.

*** 103 *"*

~---------------------~-AGPS--..r.t

pms--

MICROGRAPHIeS BUREAU ----~------------~--lIIIIIiIIIIIR

DEPOSIT CHARACTERISTICS: STYLE: Discordant , Stratabound AGE OF MINERALISATION: paLaeoLoic permian AGE OF MINERALISATION:

paLa~ozoic

Carboniferous

DIMENS IONS: NATURE OF MINERALISATiON: MINERALOGY: GEOLOGICAL SETTING OF MINt:;:M ISATION: ORlOBODY: Harpers The deposit is set in a broad ferruginous cLay-~ossan sheared sediment zone at the contact between granodiorite intruslves and ChiLLagoe Formation sediments and Limestone. REFERENCES: Broadhurst E. , 1952 The geoLogy of the Mungana-Redcap area, ChiLLagoe district. AusIMEng. proceedings 164/165 P5-30 Gregory P.W. , TayLor R.G. , White A.H. ,1980 MineraLisation in the Broken River and Hodgkinson provinces. IN Henderson R.A. & Stephenson P.J.(eds) - GeoLogy and geophysics of northeastern AustraLia. 3rd AustraLian GeoLoglcaL convention, Townsv i LLe, 1978. GeoLogicaL society of AustraLia 1v d; Keyser F. , BayLy M.B. , WoLff K. , 1959 The geoLogy and mineraL deposits of the ~lungana, Chi LLagoe, and ALmaden 1-miLe Sheets, north QueensLand (Part 1). Bureau of MineraL Resources, AustraLia. Record 59/108 de Keyser F. , Lucas K.G. , 1968 GeoLogy of the Hodgkinson and Laura Basins, north QueensLand. Bureau of MineraL Resources, AustraLia. BuLLetin 84 0000000000000000000000000000000000000000

.

----------~------------~&~-AGPS--

plII=I-- MICROGRAPHIeS BUREAU -------------------!IIIE!lll DEPOSIT:

9

CROYDON

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: Au , Ag , MINES: Croydon, Federation, GLen,;oe, GoLden Gate 1 North ConsoLs, No. 3 And 4 Soutn , No. 5 South, TabLetop ,

GoLden

OREBODIES: Croydon, Go Lden Gate , Go Lden Va LLey , Ha rp Of Eri n Mary-CaLedonia , Homew;;;rd Bound , Iguana-Lady Mary , Croydon-Richmond, Marr Twain, Moonstone, Mountain Maid , Croydon-Waratah , Tab'.etop , True BLue-Lady IsabeLLe-Content Mi Le , waratah ,

Gate

Hi gh Land Ki ng Of Queen Of TWe Lve

GROUP: croydon Group COMMENTS: Includes regionaL srtting of Croydon Subprovince. See Deposit No. 10 Geor~etown for regionaL setting of Georgetown InLier. Record covers Croydon fieLd, WhlCh is distributed over beLt 30km x 20km east of Croydon. LOCATION: LATITUDE: 18 12 250K SHEET: SE54 11

LONG nUDE: 142 17 100 K SHEET: 7361

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: ~lareeba MINING FIELD: Croydon LOCALITY : DEV ELOPNENT HIS TORY: DISCOVERY METHOD prospecting

DISCOVERY YEAR 1885 OPERATING STATUS AT 1987 MINE Croydon No. 3 And 4 South GoLden Gate Conso Ls Go Lden Gate North No. 5 South Federation

STATUS Historica L HistoricaL

MINING ~lETHOD Unde rg round Underg round

HistoricaL

Underground

HistoricaL

Unde rg round

HistoricaL Ope rati ng

Unde rg round Open-Cut

*** K03 *** ra---------------------tiil-AGPS--1IIIil

.----MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -... open-Cut Open-Cut Tai Li ngs Re-Treatment

operating Comp Leted Operating

GLencoe TabLe top croydon

COMPANIES: OREBODY: Croydon COMMENTS

PRESENT OPERATORS: Barrack Mines Ltd. EQUITY 66.67 33.33

pRESENT OWNERS: centraL Coast EXPLoration N L. pancontinentaL Mining Ltd.

r.

COMMENTS

OREBODY: GoLden Gate COMMENTS

PRESENT OPERATORS: Barrac k Mi nes Ltd. EQUITY 66.67 33.33

pRESENT OWNERS: centraL Coast ExpLoration N L. panconti nenta L Mi ni ng Ltd_

r.

CNIMENTS

OREBODY: Tab Le top COMMENTS

pRESENT OPERATORS: centraL Coast EXPLoration N L. EQUITY 100.00

pRESENT OWNERS: centraL Coast ExpLoration N L.

r.

COMMENTS

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 735,554

GOLD(kg) 24,033

RECOVERED GRADE(g/t) 32.67

COMMENTS

MAIN PRODUCTION PERIODS: 1886-1919, (1931-1943), (1984-1985),1987- , RESOURC ES:

---------DATE

ORE(' OOOt)

GRADE(g/t)

GOLD(kg)

CLASSIFICATION

Dec 1987

1,500

3.6

5,370

Economic Demonstrated In-Situ

olc

Dec 1987

1,004

3.4

3,413

1,340

4,408

Economic Demonstrated RecoverabLe - Measured Economic Demonstrated RecoverabLe

olc

3.3

Dec 1987

olc

Centra L Coast tenements Cent ra L Co as t tenements panconti nenta L tenements

PRE-MINE RESOURCE SIZE: M

....

***

L03

***

..

~-AGPS--

-

MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - - . GEOLOGY: PROV INCE: BLOCK: PROVINCE: Georgetown Inlier SUB-PROVINCE: Croydon SUbprovince HOST ROCKS: Esmera lda Grani te Fine to coarse locally porphyritic biotite adamelLite and granite. MineraLisation comprised shallowly dipping subparallel quartz reefs zones
in

shear

Croydon Vo Lcani c Group RhyoLite and rhyodacite flows and i9nimbrites. MineraLisation comprised s~mple pyr1tic quartz reefs. VoLcanic-hosted deposits were more numerous but smaLLer ana Less productive than granite-hosted deposits. AGE: Proterozoic MiddLe STRUCTURAL FEATURES MAJOR: FauLting, Fracturing, Shearing, STRUCTURALlSTRA TIGRAPHIC INTERS ECTIONS MAJOR: Intrusive Contact, IGNEOUS PROXIMITY MAJOR: plutonismCGranite) , VoLcanismCFelsic) , AGE OF INTRUSION: proterozoic MiddLe METAMORPHISM: Regional metamorphic grade is amphibolite facies. ALTERA TlON: DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. Auriferous quartz veins in felsic volcanics adjacent to granitoid. STYLE: Discordant , MORPHOLOGY: Lenticular, AGE OF MINERALISATION: proterozoic MiddLe DIMENS IONS: OREBODY: Croydon

MIN

AVE

MAX

,~**

M03 ***

-AGPS _ _-.11

....--MICROGRAPHICS

m ) STRIKE LENGTH cm ) TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: Highland Mary-Caledonia

MIN

AVE

MIN

AVE

MIN

AVE

m m

STRIKE LENGTH VERTICAL DEPTH ORE80DY: Homeward Bound

m ) STRIKE LENGTH cm ) TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: Iguana-Lady Mary m ) cm ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: M3rk Twain

STRIi
2500.0 900.0 150.0

m ) cm ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH ORE30DY: Golden Gate

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Mountain Maid

...

BUREAU-----mro~------------

( ( (

m ) cm )

30.0 90.0 MIN

AVE

45.0 50.0 ~lIN

AVE

MIN

AVE

m)

m ) cm ) m )

210.0 60.0

MIN ( cm ) 300.0 TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: True Blue-Lady Isabe lle-Content MIN 300.0 m ) STRIKE LENGTH ) m 55.0 VERTICAL DEPTH OREBODY: TWe lve Mi le MIN m) STRIKE LENGTH cm ) TRUE WIDTH m) VERTICAL DEPTH

AVE

AVE

75.0 AVE

MAX

2500.0 900.0 140.0 MAX

460.0 25.0 MAX

2500.0 45.0 130.0 MAX

725.0 460.0 75.0 MAX

1600.0 45.0 40.0 ~lAX

250.0 100.0 110.0 MAX

500.0 50.0 MAX

600.0 110.0 MAX

2000.0 100.0 50.0

NATURE OF MINERALISATION: Free Mi l,ing , oxidised, primary, Refractory, PRIMARY O~E: Lode (Alteration Zone) , Vein (Reef) , MINERALOl ;: ORE80DY: Croydon sulphide ore (granite): quartz, graphite, arsenopyrite, pyrite, calcite, galena, sphalente, gold r si lver, but sulphide content was generally low. Galena indicated nigh-grade ore. Graphite was a constant gangue mineral in the gramte-hosted orebodies. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: croydon

. . . . ._ _...

***

N03 *** ,a..":

lIiID_ AGPS _ _

..tl

.--~MICROGRAPHICS BU RE AU .--- --- --- ---...- - - - - - -... .. REGIONAL SETTING: CROYDON SUBPROVINCE The Croydon subProv ince consist s almost entireL y of a vast continen taL feLsic ignimbr ite terrain of Middle protero zoic age (Croydo n Volcani c Group) intruded at the margins by probabl y adameLL ite and granite (EsmeraL da Granite ). comagma tic biotite The voLcani cs compris e up to 400 m flow-ban ded dark grey porphy ritic rhYolite and rhyodac ite fLows overlain two sheets of rhyodac itic ignimbr ite (welded tuff). The igneous by rocks are bounded by a series of intersec til'lg recti Linear faults which Paralle l major structu ral trends in the Forsayth Suborov ince to the east. Graphit ic zones in both granite and voLcani cs probabL y origina ted from the assimi Lation of carbOna ceous sedimen ts. The subprov ince has been interpr eted as a cauldro n subsiden ce area (Branch , 1966) which evoLved by re-activ of pre-eXi sting underlyi ,.,g zones of weaknes s. Extrusio n of rhyoliteation flows from boundarY fissures and vents was folLowe d by the erul'tion of ignimbr ite and subside nce of the cauldro n block alol'lg the margina l faults. Granite was subsequ ently empLaced under tension 11'1 the margina l fauLt zones. GEOLOGICAL SETTING: CROYDON The Croydon goldfie ld occurs in llranite and voLcani cs in the northwe stern part of the subprov 1nce the densely faulted margina L zone. The igneous rocks are cut by 2 in main sets of faults, one northstriking and near vertical Ly-dipp ing, and one north-n orthwes t strikin g. Disp Lact!ments are Less than 30 m. i~re than 3/4 of product ion came from the Esmeral da Granite . Granite hosted lodes compris ed zones of sheared and graphit ic granite up to 9 m wide traverse d by numerou s quartzgranite veins and reefs. Ore shoots were locaLise d i) at the interse ctlon of the lodes with zones of graphit ic granite ; ii) on the southwe st sides of the intersec tions of ~he lodes with north-w est strikil'l !l' west-dip l'ing reverse faults against which the lodes termina ted; iii) 1n associa tion with smalL northpitchil'l g drag foLds. Lodes were sLightl y transgr essive to the beLts of graphit1 c ~ranite, which 25-45 deg NE. volcani c ( felsite" )-hostedip d orebodi es were simpLe quartz reefs. OREBODY: Golden Gate GO Lden Gate lode account ed for more than one-thi I'd of the tota l product ion of the fieLd. The lode channe' extende d from the Sunset lode (southw ards extensio n of Golden northwa rds for 5600 m. The Lode was a com>Jound reef with numerou sGate) splits and branche s. ore zones were termina ted at depth by reverse faults. OREBODY: Highland Mary-Ca Ledonia Highlan d Mar)' lode was intersec ted by a westerl y-dippi ng fault at 90m and downfau Lted to the side to 110m. caLedon ia was a cross lode, east aLso interse cted at depth by the Westdipping fau It. OREBODY: Homeward BOund Line of reefs occurs in graphit ic tuff. OREBODY: Iguana-L ady Ma ry ore zones termina~ed at depth against a westerL y-dippin g fauLt. OREC30DY: Mark Twa1n Hosted by massive quartz "felsit e". OREBODY: TabLetop Reefs occur i n gr~phiti c tuffs, quartz "fe ls ites" a:1d agg Lomerat es. OREBODY: TWe lve M1 le Reefs are hosted by graphit ic tuffs. REF ERENC ES: Bain J.H.C.

~

-

, withnaL l I.W.

---

, 1980

***

A04 ,~**

- _ - - - - - - _.. .. [(i ~-A GPS- _.. ..

....- - MICROGRAPHICS BUREAU

"'IIRlII!

_~

"'"

MineraL deposits of the Georgetown region, northeast QueensLand. IN Henderson R.A. & Stephenson P.J. (eds) - The geoLogy and geophysics of northeastern AustraLia. GeoLogicaL Society of AustraLia. QueensLand Division 1v p129-148 Branch C.D. , 1966 VoLcanic cauLdrons, ring compLexes, and associated granites of the Georgetown InLier, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 76 BrooksJ.H. ,WoLffK. ,1959 Government dri LLing - GoLden Gate area, croydon. QueensLand Government Mining Journal 60 p263-271 Bureau MineraL Resources, Aust , 1985 Croydon Region SpeciaL, QueensLand, 1:250 000, geoLogicaL map. SE/54-12( SE/54-11, 1st edition. Bureau MlneraL Resources, AustraLia 1v

Sheets

Cameron W. E. 1911 Bennion's Block mine, Croydon. Queens Land Government Mi ni ng Journa l 12 p282 Cameron W.E. , 1931 The GoLden Gate, Croydon. Prospects for further goLd quartz occurrences in this area. Queens Land Government Mi ni ng Journa L 32 P48-49 CLappison R.J .S. , Dickinson S.B. , 1937 The fe Ls i te auri fe rous area, Croydon go Ld and mi ne ra L fi e Ld. AeriaL, GeoLogicaL & GeophysicaL Survey of Northern AustraLia. 25

QLd Repor

Dunstan B. , 1905 Some Croydon goLd mines. parts I and 11. GeologicaL Survey of Queens Land. Publication 202; 212 Dunstan B. , 1906 Some Croydon goLd mines. Queens Land Government Mi ni ng Journa L 7 P183-19O Dunstan B. , 1906 The "ighLand Mary reef and Bennion's mine, Croydon. Que', ,,; Land Government Mi ni ng Journa L 7 P466-467 Dunstan B. , 1907 Some Croydon gold mines. With special reference to Bennion's reef and the HighLand Mary reef. Queens Land Government Mi ni ng Journa L 8 P224-230 Edwards A.B.

, 1953

***

B04

***

e-.---------------------~~-AGPS--!IIII

. - - - MICROGRAPHICS BUREAU----------~-------~ THe croydon goldfield. IN Edwards A.B.(ed) - Geology of Australian ore deposits. 5th Empire Mining & Metallurgical Congress, Australia & New Zea land, 1953, Me lbourne. Aus IMM 1v P7B3-795 Queens land. Department of Mi ne 1986 Queensland mining historical col(ection - Croydon. Includes historical booklet I GO ldfi e lds of Queens land' by W. Lees, 1899 and 2 maps by W. H. Rands, 1896. Queens land. Department of Mines 1v Queens land. Depa rtment 0 f Mi ne , 1986 croydon, Queensland, 1:100 000, mine map series. edi ti on. Queens land. Department of Mi nes 1v Rands W.H. , 1896 Croydon go ldfi e ld. Geological Survey of Queensland. 118

sheet 7361, 1st

PubLication

Sti llwe II F .L. , 1937 Rock specimens from Croydon goldfield, Qld. CSIRO. Mineragraphic Report 111 Warnick J. , 1986 Mines and mineral deposits of the Croydon region. Geological Survey of Queensland. Record 1985/42 0000000000000000000000000000000000000000

...

------~---------------[Ii~-AGPS--

..

. - - - MICROGRAPHIeS BUREAU _ _!IISII3

DEPOSIT:

10

-..

GEORGETOWN

DEPOSIT IDENTIFICATION: SYNONYMS: Etheridge , PRINC IPAL COMMODITIES: Au ,

pb ,

Ag ,

MINES: City Of GLasgow, CumberLand , Durham, Georgetown , Lord George ,

Byron

St.

ORESODIES: Aurora, setter Luck, caLedonia, City Of GLasgow, CumberLand, Durham , Georgetown , InternationaL, Lane Creek, Lord Byron, Lord NeLson , OLd Man, Papa, Spero ~leLiora , st George , Wexford, GROUP: Etheridge Group COMMENTS: IncLudes regionaL setting of Georgetown InLier, Forsayth Subprovince, and Etheridge group. Record covers Georgetown fieLd = town area reefs + reefs in outer, NW-trending zone 15km x 7km. LOCATION: LATITUDE: 18 18 250K SHEET: SE54 12

LONGITUDE: 143 33 100K SHEET: 7661

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Georgetown MINING FIELD: Etheridge LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD Prospecti ng

DISCOVERY YEAR 1869 OPERATING STATUS AT 1987 MINE City Of GLasgow CumberLand Durham Georgetown Lord Byron st. George Georgetown Georgetown

STATUS HistoricaL HistoricaL Historica L HistoricaL HistoricaL HistoricaL

possib~e

Operatlng

MINING METHOD Unde rg round Underground Unde rg round Underground Underground Unde r!;j round Open- .ut ALLuv i a L

..

-----------------~------IJlii]I-AGPS--

.-.--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - - . COMPANIES: OREBODY: Georgetown COMMENTS

PRESENT OPERATORS: Dundas Go ld Corp N L. EGUITY 50.00 50.00

PRESENT OWNERS: Dundas Go ld Corp N L. Falcon Australia Ltd.

r.

COMMENTS

PRODUCTION:

CUMULATIVE PRODUCTION
GOLDCkg) 4,800

RECOVERED GRADE(g/t) 44.22

COMMENTS

MAIN PRODUCTION PERIODS: 1870-1920 , 1 984- , RESOURCES:

---------DATE

ORE('OOOt)

GRADE(g/t)

GOLD( kg)

CLASSIFICATION

Dec 1987

3,831

0.4

1,417

Economic Demonstrated In-Situ - Measured

a lv

Dec 1987

990

0.3

316

a lv

Dec 1987

1,200

0.5

600

Economic Demonstrated In-Situ - Indi cated Economic Inferred In-Situ

Units are: OREC'OOO cubic m) ~R~D~(~/cubic m)

a lv

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: PROVINCE: Georgetown Inlier SUB-PROVINCE: Forsayth Subprovince HOST ROCKS: Forsayth Grani te Locally foliated medium to coarse porphyritic biotite granite. Mineralisation comprised auriferous quartz vein fissure fi llings steeply dipping fractures and shear zones.

in

generaLly

Brandy Hot Granodiol'ite Medium to coarse, siJarsely porphyritic muscovite-biotite granodiorite. As in Forsayth Granite.

***

E04

,~*,~

.....-~-----------~-----. ... [fi]I-AGPS--..

.----MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - 1 I I I l ! l I l I I I I Robe rtson River Subg roup Calcareous, commonly carbonaceous Labi Le schist, quartzite. As in Forsayth Granite.

mudstone,

si Ltstone,

sandstone;

mica

Lighthouse Granite Foliated medium muscovite-biotite Leucogranite and pegmatite, As in Forsayth Granite. AGE: P rote ro zoi c Ear ly STRUCTURAL FEATURES MAJOR: FauLting, SIGNIFICANT: Faulting, FoLding, Fracturing, Shearing, STRue TURA LIS TRATIGRAPHIC INTERS EC nONS MAJOR: FauLt/FauLt, Intrusive Contact, SIGNIFICANT: Intrusive Contact, IGNEOUS PROXHlITY MAJOR: P Lutoni sm (00 Le ri te) , P Lutoni sm (Grani te) , SIGNIFICANT: P Lutoni srn (Do Le ri te) , P Lutoni srn (Grani te) , AGE OF INTRUSION: Proterozoic

~liddLe

METAMORPHISM: RegionaL metamorphic grade is Lower to upper amphiboLite facies. ALTERA nON: Mineralisation was associated with si Licification, chLoritisation and epidotisation, and sericitisation in some places. DEPOS IT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. Auriferous quartz veins in metasediments adjacent to granitoid. STYLE: Discordant, Stratabound , MORPHOLOGY: LenticuLar, AGE OF MINERALISATION: paLaeozoic permian AGE OF MINERALISATION: PaLaeozoic Carboni ferous AGE OF MINERALISATION: Proterozoic MiddLe DHIENSIONS: OREBODY: Aurora STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Bette r Luc k

m) cm ) m)

MIN

AVE

30.0 ~lIN

AVE

MAX

100.0 60.0 30.0 MAX

***

F04

,~,~*

-AGPS---1IIlIl

MICROGRAPHICS BUREAU TRUE WIDTH VERTICAL DEPTH OREBOOY: CaLedonia

cm ) m )

( m ) STRIKE LENGTH ( cm ) TRUE WIDTH ( m ) VERTICAL DEPTH OREBODY: city 0 f GLasgow

100.0 87.0

30.0 MIN 15.0 7.5

AVE

MAX 30.0 38.0 100.0

MIN

AVE

MAX 110.0 45.0 30.0

MIN

AVE

MAX 450.0 130.0 340.0

mN

AVE

MAX 150.0 370.0 120.0

15.0

AVE 200.0 100.0

10.0

20.0

MAX 550.0 400.0 335.0 30.0

~lIN

AVE

MAX 150.0 60.0 110.0

MIN

AVE

MAX 245.0 90.0 40.0 MAX 1000.0 100.0

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: cumberLand

m ) cm ) m )

TRUE WIDTH STRIKE LENGTH VERTICAL DEPTH OREBODY: Durham

cm ) m ) m )

STRIKE LENGTH TRUE WIDTH V ERTICAL DEPTH OREBODY: Georgetown

m ) cm ) m )

STRIKE LENGTH TRUE IHDTH VERTICAL DEPTH DEPTH OXIDATION OREBODY: InternationaL

m ) cm ) m ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Lane Creek

m ) cm ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Lord Byron

m ) cm ) m )

30.0 20.0 MIN

AVE

STRIKE LENGTH TRUE WIDTH OREBODY: Lord Ne Lson

m ) cm )

30.0

35.0 AVE

m ) cm ) m )

~lIN

STRIKE LENGTH TRUE WIDTH V ERTICAL DEPTH OREBODY: OLd Man

MAX 300.0 100.0 80.0

MIN

AVE

TRUE WIDTH OREBODY: Papa

cm )

MAX 45.0

MIN

AVE

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Spero MeLiora

m ) cm ) m )

MAX 760.0 180.0 100.0

MIN

AVE

MAX 400.0 180 .0 30.0

STRIKE LENGTH TRUE WIDTH V ERTICAL DEPTH OREBODY: St George

12.0

5.0 MIN

( m ) ( cm ) ( m )

5.0

90.0

***

G04

M,*

~-AGPS

.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -IIISIII STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: wexford

m ) cm ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH

m ) cm ) m )

~lIN

AVE

7.0

30.0

~lIN

AVE

30.0

MAX

60.0 50.0 100.0 MAX

50.0 120.0 55.0

NATURE OF MINERALISATION: Disseminated, Free MiLLin9 ' oxidised, PrimarY, Refractory PRIMARY ORE: Lode (ALteratl0n Zone) , MuLtipLe Veins, Vein (R~ef) , MINERALOGY: OREBODY: Aurora suLphide ore: coarse goLd, quartz, pyromorphite. OREBODY: caLedonia suLphide ore: arsenopyrite, some gaLena. OREBODY: City Of GLasgow sulphide ore: mainly pyrite, minor galena. OREBODY: cumberland sulphide ore: two-thirds pyrite, one-third galena. OREBODY: Durham SU lphi de ore: pyrite. OREBODY: Georgetown sulphide ore: pyrite, galena, sphalerite, chalcopyrite. Gold content followed pyrite and galena content. The reefs ranged in composition from pure white quartz to nearly pure masses of sulphides. Reefs in granite carried a higher suLphide content. oxide ore ("brownstone"): Fe-stained quartz and gossan containing limonite, hematite, locally cerussite, malachite, azurite. OREBODY: International sulphide ere: native gold, native silver, native lead, pyrite, galena, sphalerite, siderite, quartz. OREBODY: Lord Nelson sulphide ore: Less than 57. pyrite and chalcopyrite. OREBODY: Papa sulphide ore: galena, pyrite, chalcopyrite, sphalerite, arsenopyrite. OREBODY: Spero Meliora sulphide ore: pyrite, sphalerite. OREBODY: st George sulphide ore: minor pyrite, chalcopyrite, galena. OREBODY: Wexford sulphide ore: pyrite, minor galena. GENETIC CONTROLS: On a local scale, controls of goLd mineralisation in the Forsayth subprovince (Georgetown group) are firstly structural and secondly lithological. Structural - deposits are localised in fissures which are aligned along westerly, northwesterly and northerly regional structural trends. Lithological - deposits are generally spatially related to the Forsayth Batholith; however, the lode fissures are much younger than !he granit~, as they post-date most, if not all, phases of deformation 1 n the reglon. On a regional scale, the distribution of gold deposits is spatially related to a number of geological features, all of which may have contributed to the formation of the deposits. i) Almost aLL the deposits Lie within the outcrop area of Robertson River Formation;

....

*** H04

*,~*

..

~-AGPS--

MICROGRAPHIeS

BUREAU--------------------I

ii) Within this area, deposits are concentrated within or adiacent to the Forsayth BathoLith (or other Proterozoic or Si Luro-Devoman granitoids) but are not associated with any particuLar phase of the ~ rani te comp Le X; lii) Deposits are most abundant where metabasic igneous rocks are most common; iv) Deposits are generaLLy within amphiboLite facies ro~ks east of the amphiboLite-greenschist facies boundary; v) Most of the deposits faLL within the zone of Permo-Carboniferous igneous rocks; bowever the greatest concentration occurs within a restricted zone in which Late PaLaeozoic igneous rocks are absent; vi) The area of Late PaLaeozoic igneous rocks coincides with a regionaL gravity Low, possibLy indicative of granitoid magma at shaLLow depth; however the mineraLised zone is characterised by LocaL gravity highs, possibL)I indicative of granitoid magma at deeper crustaL LeveLs. Oxygen isotope data (GoLding & others, 1987) indicate a magmatic or metamorphic ore-fLuid source. GENETIC MODELS: White (1965) postuLated that much of the goLd was introduced by the Forsayth BathoLith, some by the CobboLd ~letadoLerite. Considered unLikeLy because mineraLisation is younger than both granite and metado Le ri te. Withna LL (1976) suggested that the goLd may have been introduced by the younger phases of the bathoLith, but mineraLisation dispLays no cLose affiliation with these phases. Baker (pers. comm. to WithnaLL, 1978) postuLated that the Forsayth Batholith acquired precious metaLs b)l the assimi Lation of metaL-rich metamorphic rocks, and that the metaLs were subsequently remobi Lised by circuLating groundwater driven b)l a si Luro-Devonian or Carboniferous heat system and redeposited in hi~h LeveL fracture systems. under this modeL, however, more Larger deposlts wouLd be expected in the i'letamorphi cs tnan are known. Bain (1980) modified the modeL and proposed a muLti stage origin in which aLL of the observed reLated regionaL geoLogicaL features contributed to ore formation. i) ~lafic igneous rocks of the Robertson River Subgl"oup carried high precious (and other) metaL contents which were Leached and deposited as suLphides in interflow positions and fractures during cooLing. ii) GoLd was remobiLised under amphiboLite facies metamorphic conditions and redeposited in structuraL sites e.g. in fractured !i1ranitoids. ,ii) MineraLisation was further concentrated by proLonged and intense hydrothermaL activity during cooLing of a Large subsurface granite bathoLith in the Late PaLaeozoic. The existence of deep fracture sets in the upper LeveL of the strained Forsayth BathoLith provided mineraLising fluids with access to higher cooLer LeveLs and suitabLe depositionaL spaces. iv) FinaL upgrading occurred with weathering and oxidation in the nearsurface zone. GEOLOGICAL SETTING OF mNERALISATION: OREBODY: Aurora Reef Lies in Forsayth Granite (s.s) south of GoLden Bar FauLt near contact with mudstone and siLtstone of the Lane Creek Formation (Robertson River Subgroup). The reef channeL straddLes the contact but was auriferous in the granite onLy. Lane Creek Formation is intruded by Cobbo Ld Me tado Le ri te. Hos t g rani te is medi um to coa rse porp hyri ti c biotite granite. OREBODY: Better Luck

plIIIlII--MICROGRAPHICS

BUREAU---::lI8IIIl---------------.

Reef is in porphyritic biotite granite of Forsayth Granite (s.s.). The reef is one of the inner Georgetown centre reefs, which lie west of a major north-south trending fault, the Delaney Fault. The reefs occur near a contact with sediments of tne Daniel Creek Format10n (Robertson River Subg roup). OREBODY: caledonia Reef lies within Forsayth Granite (s.s) south of an east-northeasterly tren~ing fault zone. Host rock is medium to coarse porphyritic biotite granlte. OREBODY: city Of Glasgow Reef is hosted by fine-grained quartz-mica schist and quartzite (~Iount Helpman Member, Daniel Creek Formation) of the schist phase of the Robertson River Subgroup. ;he metasediments are cut by medium even to porphyritic muscovite-biotite leucogranite (Lighthouse Grani te or Delaney Granite). Mineralised zone consisted of "brownstone" = ferruginous quartz vein. OREBODY: cumberland Reef is centred on fault intersection within medium to coarse sparsely porphyritic muscovite-biotite granodiorite (Brandy Hot Granodiorite). OREBODY: Durham Reef lies in coarse porphyritic biotite granite [Forsayth Granite (s.s.)]. OREBODY: Georgetown REGIONAL SETTING: GEORGETOWN INLIER The Georgetown Inlier contains Proterozoic metamorphics and granite, and Late Palaeozoic volcanics and granite. The inlier is fault-bounded against palaeozoic fold belts to the northeast and southeast, and overlapped by Mesozoic and cainozoic sediments to the northwest and southwest. The geology is complex and some of the earlier mapping [e.g. White (1965)] has been re-interpreted with the assistance of detai led geochemical and geochronological studies. The stratigraphy followed herein is that of Withnall & others (1980) and 8ain & others (1985). The precambrian rocks have been divided into 3 subprovinces, from the east, the Greenvale, Forsayth and CroYAon subprovinces. REGIONAL SETTING: FORSAYTH SU8PROVINCE The proterozoic metasedimentary sequence (Etheridge Group) is exposed in a broad discontinuous northerly-trending be lt younging westwards in the central-eastern part of the Forsayth Subprovince. Grade of metamorphism within the group decreases southwestwards. The oldest rocks of the inlier are upper amphibolite to granLllite facies biotite and calc-silicate gneiss, amphibolite, migmatite, schist and quartzite (Einas leigh Metamorphics). The high-grade rocks are correlated with amphibolite facies calcareous and caLc-silicate schist, quartzite, granofels and marble, and greenschist facies calcareous sandstone~ si ltstone and shale (Bernecker Creek Formation) to the south; and overlying lower to upper amphibolite facies quartz-mica schist, quartzite and amphibolite, and low greenschist facies shale, S1 ltstone, sandstone and mafic volcanics (Robertson River Subgroup) to the west. The Robertson River Subgroup is extensively intruded by dolerite (Cobbold Metadolerite). The Etheridge Group is interpreted [Day & others (1983)] as originally a shallow mar1ne sedimentary sequence deposited in a stable shelf envi ronment. The metasediments were multiply deformed, the oldest units by at least 5 deformation events. The early events, isotopically dated at 1570, 1470 and 970 m.y. (see Geochronology), produced tight to isoclinal complex folds and greenschist to upper amphiboLite metamorphism, and were accompanied by the emplacement in the Middle proterozoic of extensive composite syntectonic granitoid batholiths (mainly Forsayth 8atholith) in the amphibolite grade rocks.

**,~

J04

,~**

-AGPS---.aI

flIlIlIIIII-- MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - 1 I I l I I I I I f I WithnaLl & others (1980) subdivided the Forsayth BathoLith into 9 units, ranging in composition from gneissic Leucogranite to porphyritic biotite granite. The oLder pLutons occur at the bathoLith margins. Larger p Lutons of Forsayth Granite surrounded by s.uaLLer bodies of the younger phases make up the main part of the bathoLith. REGIONAL SETTING: CROYDON SUBPROVINCE The western part of the inLier is occupied mainLy by extensive sheets of continenta L porphyritic rhyoLitic ignimbrite (Croydon VoLcanic Group) comagmatic biotite granite (EsmeraLda Granite). Both granite and voLcanics are IJraphitic. Branch (1966) interpreted the Croydon Subprovlnce as a cauLdron subsidence structure. The Croydon VoLcanics may be the extrusive equivaLent of the MiddLe Proterozoic pLutonism that affected the centraL part of the inLier. , The Proterozoic rocks are extensiveLy intruded by and/or overLain by a suite of Permo-Carboni ferous caLc-aLkaLine cauLdron-subsidence voLcanics, ring compLexes and hypabyssaL stocks (e.g. NewcastLe Range Vo Lcani cs). The main structuraL trends are west, northwest and north. ASSOCIATED MINERALISATION GoLd mineraLisation is associated with Proterozoic granitoids and metamorphics in the centraL Forsayth Subprovince (Etheridge goLdfieLd, e.g. Georgetown, Forsayth, Gi Lberton); and with Proterozoic voLcanics in the younger Croydon Subprovince to the west (Croydon). EPithermaL type mineraLisation is associated with Late PaLaeozoic voLcanic compLexes (e.g. Kidston). GEOLOGICAL SETTING: ETHERIDGE GROUP The majority of goLd deposits in the Etheridge group (Etheridge GoLdfieLd), especiaLLy the Large ones! occur within IJranitoids of the Forsayth BathoLith;, a great many smaLl deposits Lie ln the metasedimentary rocks adjacent to the gr'Jnites. Most of the deposits Lie in the amphiboLite facies zone near the boundary with the greenschist facies to the west; and are generaLLy concentrated in areas where metabasic rocks are most common in the metamorphics. ALmost aLL of the deposi ts Lie withi 1'1 the Pe rmo-Ca rboni fe rous igneous te rrai 1'1, but the greatest concentration of mineraLisation is in a beLt in which Late PaLaeozoic igneous rocks are absent. The most common type of deposit was a mineraLised quartz vein in a steepLy-dipping shear or fracture zone in granite or schist. In somi! cases favourabLe metasedimentary bands were repLaced by quartz. Some reefs consisted of a singLe quartz vein, others a zone of muLtipLe subparaLLeL veins and stringers. The smaLLest deposits were generaLLy a network of thin stringers. Reefs were aLigned al.ong one of the regionaL structuraL trends. The major north-striking DeLaney FauLt which passes through Georgetown and Forsayth contains no quartz reefs and probabLy post-dated mineraLisation. OREBODY: InternationaL Reef Lies in aLtered biotite microgranite, which WithnaLL (1978) shows as Carboniferous Eva Creek Microgranite, out which Bain & others (1985) show as Forsayth Granite (s.s.). The deposit occurs near contact with mudstone and si Ltstone of the Lane Creek Formation (Robertson River Subgroup). The Lane Creek Formation is intruded by CobboLd MetadoLer)te in the deposlt area. OREBODY: Lane Creek Reef Lies in mudstone and si Ltstone of the Lane Creek Formation at contact wi th Cobbo Ld Metado Le ri te. OREBODY: Lord Byron Reef was the Largest of a group of reefs Lying aLong a northeasterLytrending Lineament which traverses the contact between Forsayth Granite (s.s.l and DanieL Creek Formation (Robertson River Subgroup).

t:** K04 *** t v - n - - - - - - - - - - - - - - - - - - - - - - - L i i j ] - A G P S _ _1IlIII

pIlI-- MICJROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - . Lord Byron was associated with a small mass of porphyritic biotite granite identified as Mistletoe Granite, within the metasediments. OREBODY: Lord Nelson The reef was the most productive of the Lighthouse group, which was hosted by mica schist and quartzite of the Daniel Creek Formation and Mount Helpman Member (Robertson River Subgroup). The metasediments are intruded by medium porphyritic muscovite-biotite granite of the Delaney Granite ana by dolerite of the Cobbold Metadolerite. The presence of numerous granite outcrops indicates that the metasediments are underlain by granite at a relatively shallow depth. The reef is discordant to the follation in the ho~t rocks. OREBODY: 0 ld Man Reef occurs at the contact between porphyritic biotite granite of the Forsayth Granite (s.s.) and schist and quartzite of the Daniel Creek Formation (Robertson River Subgroup) where the metasediments are intruded by cobbold Metadolerite. OREBODY: papa The Papa (or Grandpapa) reef is the northernmost of the St. George-PapaTelegraph group, the reefs of which probably lie on the same northtrending hssure in white leucogranite of the Lighthouse Granite. The group llPS on the western side of a major north-trending fault, the Delaney fault, and is close to contacts with Forsayth Granite (s.s.) and with metasediments of the Daniel Creek Formation (Robertson River subg roup). The Papa reef was almost devoid of quartz in places, consisti ng of an indefinite lode formation. OREBODY: Spero Me l iora Reef is hosted by coarse porphyritic biotite granite of the Forsayth Granite (s.s.). The mineralised zone consisted of "brownstone" = cavernous ferruginous portions of a quartz vein. OREBODY: st George The St George reef lay in the centre of the north-trending st GeorgePapa-Telegraph line of reefs. The group is hosted by white leucogranite of the Lighthouse Granite, and lies on the western side of the ma~or north-trending Delaney Fault close to contacts with Forsayth Granlte (s.s.) and with metasediments of the Daniel Creek Formation (Robertson River Subgroup). OREBOIlY: Wexford The reef lies on the Delaney Fault, a major north-trending fault zone which passes through Georgetown, wnere it forms the contact between Forsayth Granite and Mistletoe Granite. The reef occupies a shear zone in sheared porphyritic biotite granite (Forsayth Granite) and schist, and consisted of "brownstone" = ferrLlginous zones in quartz. REFERENCES: BainJ.H.C. ,1980 Some new ideas on the age and origin of the Etheridge Goldfield, Queensland, and their exploration implications in the AusIMM Conference, New Zea land, May 1980. AusIMM 1v pS3-66 Bain J.H.C. , Withnall I.W. , 1980 Mineral deposits of the Georgetown region, northeast Queensland. IN Henderson R.A. & Stephenson P.J. (ecs) - The geology and geophysics of northeastern Australia. Geological Society of Australia. Queensland Division

***

L04

***

__

lIImm'I-----------------------~-AGPS

1IIIlI

.----MICROGRAPHICS BUREAU

--------------------l1li

1v p129-148 WithnalL Bain J .H.C. , Oversby B.S. , Mackenzie D.E. , Moffat P. I.W. , 1985 Geology of the Georgetown region, Queensland, 1 :250 000 geo logi ca l special map. 1st edition. Bureau Mineral Resources, Australia & Ge~Logical Survey of QLd 1v Bain J.H.C. , Oversby B.S. , Withnall I.W. , Mackenzie D.E. , 1984 ~lineral depo5it~ of the Georgetown region, Queensland, 1 :250 000 scale map. Bureau Mineral Resources, Australia 1v Bain J.H.C. , WithnaLl I.W. , 1985 Mineral deposits of the Georgetown region, Queensland: production figures and bibLiography. Bureau of Minera L Resources, Australia. Record 85/ 10 Branch C.D. , 1966 Volcanic cauLdrons, ring complexes, and associated granites of the Georgetown InLier, Queens land. Bureau Mineral Resources, Australia. Bulletin 76 Cameron W.E. , 1900 The Etheridge and GiLbert goldfields. GeologicaL Survey of Queensland. publication 151 Cameron W.E. , 1901 Etheridge and Gi Lbert goldfields. Queensland Government Mining Journal 2 p22-27 P65-69 P113-114 Cameron W.E. , 1908 The Etheridge goLdfieLd. QueensLand Government Mining Journal 9 P340-348 Cribb H.G.S. , 1939 Mining in the Georgetown district, Etheridge goLdfieLd. QueensLand Government Mining Journal 40 p402-407 Denmead A.K. , 1935 Lord NeLson mine, Etherid!]e goLd fieLd. Queens Land Government Mi m ng Journa l 36 P275-276 Denmead A. K. , 1935 St George, OverLand Te Legraph, and Grandpapa (or Papa) G. M. L. I s, Etheridge goLd fieLd. QueensLand Government Mining JournaL 36 P276-27B Geraghty T.R. , 1898 ~lap of the Etheridge goldfieLd. Scale 1:63360. GeologicaL Survey of Q~eensLand. pubLication

***

M04

***

.....--MICROGRAPHICS BUREAU -

.......- - - - - - - - - - - - - - - - - - . .

137 GoLding S.D. , loIilson A.F. , Scott M. , Anderson P.K. , Waring C.L. , Flitcroft M. , Rypkema H.A. , 1987 Isotopic evidence for the diverse origins of goLd in QueensLand. IN Herbert H.K.(ed) - GoLd in QueensLand. proceedings of one-day symposium, University of Queens tand, June 1984. University of Queens land. Department of GeoLogy. papers 12 (1) P65-83 Oversby B.S. , WithnalL I.W. , Baker E.M. , Bain J.H.C. , 1978 GeoLogy of the Georgetown 1:100 000 sheet area (7661), north QueensLand: Part A. Bureau of MineraL Resources, AustraLia. Record 1978/44 WaLL L.N. , WithnaLL I.W. , 1975 Georgetown InLier - mineralization. IN Knight C.L.(ed) - Economic geo Logy of Austra Li a and Papua New Gui nea - 1 :-teta ls. AusIMM. Monograph S~ries 5 P516-518 White D.A. , 1965 The geology of the Georgetown-CLarke River area, North QueensLand. Bureau MineraL Resources, AustraLia. BulLetin 71 WithnaLl I.W. , 1978 Mines and mineraL deposits of the Georgetown 1 :100 000 sheet area, Queens La nd. GeoLogicaL Survey of Queens Land. Report 100 WithnaLL I.W. , 1981 Contributed discussion to "some new ideas on the age and origin of the Etheridge GoLdfieLd, Queens Landt, and their expLoration impLications", by J • C. Bai n. (Proceedi ngs No .27 (, Ma rc h 1981). AusIMM. Proceedings 279 P43-45 WithnaLL I.W. , Bain J.H.C. , Rubenach M.J. , 1980 The precambrian geoLogy of northeastern Queens Land. IN Henderson R.A.& Stephenson p.J. (eds) - The geoLogy and geophysics of northeastern AustraLia. 3rd Australian GeoLogicaL Convention, Townsvi LLe, 1978. GeoLogicaL society of l,ustraLia. QueensLand Division 1v P109-127 Wi thna Ll I.W. , 1976 Summary of mineraL exploration in the Georgetown area. Queens land Government Mini ng Journa L 77 P583-599 Withna Ll I.W. , 1976 Mines and mineraL deposits of the Forsayth 1:100,000 sheet area, Queens La nd. Geo Logi ca L survey of Queens land. Report 91 0000000000000000000000000000000000000000

...._ _IiII_ .. _ ...

••

...

***

11I04

***

iiXifT_----_sr

~I!II.__

~

..

AGPS - - _ .

1llIIBII--MICROGRAPHICS BUREAU-----....~...._ - - - - - - - - - - - - - . DEPOS IT:

11

FORSAYTH

DEPOSIT IDENTIFICATION: SYNONYMS: Etheridge , PRINCIPAL COMMODITIES: Au , A9 , Cu , pb , MINES: Big Reef , caledonian (Goldsmiths) Desperandum , Queenslander ,

Forsayth

OREBODIES: Big Reef , caledonian (Goldsmiths) Desperandum , Queens lander ,

Forsayth

,

HaveLock

Nil

Havelock

Nil

GROUP: Etheridge Group COMMENTS: See Deposit NO. 10 Georgetown for regionaL setting of Georgetown Inlier, Forsayth Subprovince, and Etheridge group. Record covers Forsayth fieLd in town area + reefs in outer, N-trending beLt 10km x 7km.

reefs

LOCATION: LATITUDE: 18 34 250K SHEET: SE54 12

LONGITUDE: 143 36

100K SHEET: 7660

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Georgetown MINING FIELD: Etheridge LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD Prosp ec ti ng

DISCOVERY YEAR 1871 OPERATING STATUS AT 1987 MINE Big Reef caLedonian (Goldsmiths) Forsayth Have loc k Ni l Desperandum Queens Lander

STATUS Historical HistoricaL

MINING METHOD unde rg rou nd Underground

Hi stori ca l HistoricaL Hi sto rica L Hi stori ca L

unde rg round Unde rg round unde rg round Unde rg round

COMPANIES:

~

...

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ADS

***

~_-.::M--IMiJlIIIllIIIAGPS--"

.---MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - -.....

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORECt): 111,175

GOLDCkg) 2,480

RECOVERED GRADEC9/t) 22.30

COMMENTS

MAIN PRODUCTION PERIODS: 1871-1913 , RESOURCES:

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: PROVINCE: Georgetown Inlier SUB-PROVINCE: Forsayth Subprovince HOST ROCKS: Go ldsmiths Grani te Foliated medium variably porphyritic muscovite-biotite granite. Mineralisation comprised auriferous quartz vein fissure fi llings steep ly dipping fractures and shear zones.

in

generally

Forsayth Granite Locally foliated medium to coarse porphyritic biotite granite. As in Goldsmiths Granite. Ropewalk Granite Variably foliated medium muscovite-bil"tite granite. As in Goldsmiths Granite. Robe rtson River Subg roup Calcareous, commonly carbonaceous lal;~ le schist, quartzite. As in Goldsmiths Granite.

mud~.tone,

si ltstone,

sandstone;

mica

AGE: Proterozoic Early STRUCTURAL FEATURES MAJOR: Faulting, Shearing, SIGNIFICANT: Fracturing, Snearing , STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact,

..

*** B05

,~** ....

....

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-AGPS

-

-

-

~

. , - . - - MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - - . IGNEOUS PROXIMITY MAJOR: pLutonism(Granite) , AGE OF INTRUSION: proterozoic MiddLe DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. Auriferous quartz veins in metasediments adj acent to granitoid. STYLE: Discordant ,

stratabou~d ,

MORPHOLOGY: LenticuLar, AGE OF MINERALISATION: paLaeozoic permian AGE OF MINERALISATION: paLaeozoic Carboniferous AGE OF MINERALISATION: proterozoic MiddLe DIMENSIONS: OREBODY: Big Reef ( m ) STRIKE LENGTH ( cm ) TRUE WIDTH ( m ) VERTICAL DEPTH DEPTH OXIDATION ( m ) OREBODY: caLedonian (GoLdsmiths)

MIN

30.0 MIN

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Forsayth

m ) cm ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DOWN-DIP DEPTH DEPTH OXIDATION OREBODY: HaveLock

m ) cm ) m ) m ) m )

STRIKE LENGTH TRUE WIDTH DOWN-DIP DEPTH DEPTH 0 XIDA TION ( OREBODY: NiL Desperandum

m ) cm ) m ) m )

STRIKE LENGTH VERTICAL DEPTH TRUE WIDTH OR'EBODY: Queens Lander

m ) m ) cm )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH

m ) cm ) m )

AVE

AVE

15.0 MIN

AVE

15.0 10.0

20.0

MIN

AVE

30.0

100.0 18.0

MIN

AVE

150.0 MIN

AVE

30.0

40.0

MAX

550.0 150.0 70.0 MAX

60.0 45.0 15.0 MAX

550.0 210.0 90.0 120.0 30.0 MAX

120.0 210.0 120.0 MAX

150.0 85.0 180.0 MAX

165.0 75.0 90.0

m------------------------[iij-AGPS--d *** cos ***

pIII:II---MICROGRAPHICS BUREAU - - - - " - - - - - - - - - - - - - - - -... NATURE OF MINERALISATION: Disseminated, Free MiLLin(J , Oxidised, primary, Refractory, PRIMARY ORE: Lode (ALteratl0n Zone) , Multiple Veins, Vein (Reef) , MINERALOGY: OREBODY: Big Reef Sulphide ore: pyrite and galena in quartz and sheared granite. Oxide ore: "brownstone" = iron-stained quartz and gossan, + limonite, nematite, cerussite. OREBODY: CaLedonian (GoLdsmiths) Sulphide ore: quartz, pyrite. OREBODY: Have loc k sulphide ore: pyrite, chalcopyrite, gaLena. Reef was unusuaL in naving higher gold values in the suLphide zone than in the oxi de zone. OREBODY: NiL Desperandum sulphide ore: galena, pyrite, some chaLcopyrite, sphalerite in quartz. OREBODY: Queens Lande r sulphide ore: pyrite, galena in quartz. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Big Reef The Big Reef line of lode Lies: along a major west-northwesterly trending shear zone, the Bi(J Reef FauLt, which traverses medium variably porphyritic muscovlte-biotite granite of the Goldsmiths Granite and metasediments of the Lane Creek Formation (Robertson River Subgroup). In places the shear forms the boundary between granite and metasediment. OREBODY: caLedonian (GoLdsmiths) Reef Lies in fine-Qrained mica schist and quartzite of the Lane Creek Formation near an lntrusive mass of foLiated medium muscovite-biotite granite, RopewaLk Granite. The reef is apparently parallel to the foLiation of the host metasediments, and was introduced aLong foliation planes possibly replacing fine-grained schist Layers and forming stringers in the more competent si Liceous rocks. OREBODY: Forsayth As for Deposi t No. 10 Georgetown. OREBODY: Have loc k Reef Lies on a west-northwesterLy trending shear in porphyritic biotite granite of the GoLdsmiths Granite. OREBODY: Ni l Desperandum The reef occupies a shear zone in porphyritic biotite granite of the Forsayth Granite (s.s.). OREBODY: QueensLander Reef is in porphyritic biotite granite of the Forsayth Granite (s.s.). Gold grade apparently decreased with depth. REFERENC ES: Bain J.H.C. ,1980 Some new ideas on the age and origin of the Etheridge Goldfield, Queensland, and their exploration implications in the AusIMM Conference, New Zea land, May 1980. AusIMM 1v pS3-66 Bain J.Il.C. , withnalL I.W. , 1980 ~linera l deposits of the Georgetown region, northeast Queens Land.

***

DOS

***

IN

-AGPS--'-'

p8IlII-- MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - - -..... Henderson R.A. & Stephenson P.J. (eds) - The geology and geophysics of northeastern Australia. Geological society of Australia. Queensland Division 1v P129-148 , Withnall Bain J .H.C. , Oversby B.S. , Mackenzie D.E. , Moffat P. 1."1. , 1985 Geology of the Georgetown region, Queensland, 1 :250 000 geological special map. 1st edition. Bureau Mineral Resources, Australia & Geological Survey of Qld 1v Bain J.H.C. , Oversby B.S. , Withnall 1."1. , Mackenzie D.E. , 1984 Mineral deposits of the Georgetown region, Queensland, 1 :250 000 scale map. Bureau Mineral Resources, Australia 1v Bain J .H.C. , Withnall I.W. , 1985 Mineral deposits of the Georgetown region, Queensland: production figures and bibliography. Bureau of Mineral Resources, Australia. Record 85/ 10 Cameron W.E. , 1900 The Etheridge and Gi lbert goldfields. Geological Survey of Queensland. publication 151 Came ron W.E. , 1901 Etheridge and Gilbert goldfields. Queensland Government Mining Journal 2 P22-27 P65-69 P113-114 Cameron W.E. , 1908 The Ethe ri dge go ldfi e ld. Queensland Government Mining Journal 9 P340-348 Geraghty T.R. , 1898 Map of the Etheridge goldfield. scale 1:63 360. Geological Survey of Queens land. publication 137 Rossiter A.G. , Armstrong K.J. , 1976 Soi l samp ling at the Big Reef and TWo Mi c ks go ld mi nes, Forsayth, north Queens land. Bureau of Mineral Resources, Australia. Record 76/ 98 Wall L.N. , withnall 1."1. , 1975 Georgetown Inlier - mineralization. IN Knight C.L. (ed) - Economic geology of Australia a~d Papua New Guinea - 1. Metals. AusIM~l. ~Ionograph Serles 5 P516-518 White D.A. , 1965 The geolqgy of the Georgetown-Clarke River area, North Queensland. Bureau Mlneral Resources, Australla. Bulletin 71

1IIasr.J

,~**

EO 5

,~**

~-AGPS

_ _MlI

pm--MICROGRAPHICS

BUREAU--------------------....

Withnall I.W. ,1981 contributed discussion to "some new ideas I'ln the age and origin of the Etheridge Goldfield, Queensland" and their exploration implications", by J .c. Bain. (Proceedings No.27r, March 1981). AusIMM. proceedings 279 P43-45 Withnall I.W. , Bain J.H.C. , Rubenach M.J. , 1980 The Precambrian geology of northeastern Queensland. IN Henderson R.A.& ~tephenson P.J. (eds) - The geology and geophysics of northeastern Australia. 3rd Australian Geological Convention, Townsville, 1978. Geological Society of Australia. Queensland Division 1v P109-127 Withnall I.W. ,1976 Summary of mineral exploration in the Georgetown area. Queensland Government Mining Journal 77 pS83-S99 Withnall I.W. ,1976 Mines and mineral deposits of the Forsayth 1:100 000 sheet area, Queens land. Geological Survey of Queensland. Report 91 Withnall I.W. , 1978 Note on the Havelock mine, Forsayth 1:100 000 sheet area. Queensland Government Mining Journal 79(921) P365-367 00000000000000000000000000000000000 0 00 0 0

...

***

FOS

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~li~-AGPS

- _..

plIIIIl---MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - . DEPOSIT:

12

KIDS TON

DEPOSIT IDENTIFICATION:

PRINCIPAL COMMODITIES: Au , Ag , MINES: Kidston, Wises HilL, OREBODIES: Kidston, Macks Knob, North Knob, Wises Hi LL , GROUP: permo-Carboni ferous Igneous Group COMMENTS: Inc Ludes regionaL settin~ of Permo-Carboniferous igneous group. See Deposit No.10 Georgetown for reglonaL setting of Georgetown InLier and Forsayth Subp rov i nce. LOCATION: LA TITUDE: 1 8 52 250K SHEET: SE55 9

LONG nUDE: 144 10 100K SHEET: 7760

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Georgetown MINING FIELD: Etheridge LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng Geochemistry Dri LLinr) GeophyslCS

DISCOVERY YEAR 1907 1979 1979 1979 OPERATING STATUS AT 1987 ~lINE

Kidston Ki dston Wises Hi LL Ki dston

STATUS Histori ca l Ope rati ng OJleratl ng Histori caL

MINING METHOD Unde rground Open-Cut Open-Cut Alluvia L

CO~1P ANIES:

OREBODY: Kidston

***

GOS ,~**

-AGPS---EI

ftPIIIllIIII--MICROGRAPHleS BUREAU------------------1I!III:IIIIIIli COMMENTS

PRESENT OPERATORS: Kidston Gold Mines Ltd. PRESENT OWNERS: Placer Pacific Pty Ltd.

COMMENTS

EQUITY" 70.00

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC .1986): ORE(t): 7,686,857

GOLD(kg) 16,016

RECOVERED GRADE(g/t) 2.08

MAIN PRODUCTION PERIODS: (1907-1920) ,

COMMENTS

(1910-1934) , 1985-,

RESOURCES: ORE('ooot)

DATE May 1987

39,402

GRADE(9/t)

1.7

GOLO(kg)

CLASSIFICATION

65,407

Economic Demonstrated Recoverable

o/c

PRE-MINE RESOURCE SIZE: M GEOLOGY: PROV INCE: BLOCK: PROVINCE: Georgetown Inlier SUB-PROVINCE: Forsayth SUbprovince HOST ROCKS: Kidston Breccia pipe Zoned monomictic, bimictic, and golymictic rhyolite breccia. Frag,nents and matrix are granodiorite, metamorphics, and rhyolite. Gold-sulphide mineralisation occurs in sheeted quartz-carbonate veins tangential to pipe margin and in quartz-carbonate breccia cavity infill cement. Butlers Volcanic Group Porphyritic rhyolite, rhyolitic ignimbrite. Butlers Volcanic Group and Lochaber Granite are the main units of the Lochaber Ring Complex. The ring complex is the source of the rhyolite dykes to which the breccia pipe is genetically related. Lochaber Granite Fine to medium biotite leucoadamellite with miarolitic cavities. See Butler Volcanic Group above. Oak River Granodiorite Locally foliated medium porphyritic biotite granodiorite, hornblende-biotite tonalite. Host to mineralised breccia pipe; contributes breccia fragments.

***

foliated

H05 ,~**

-AGPS--....

. - - - MICROGRAPHICS BUREAU

IlIIIIIIIIIII_ _. . . .

EinasLeigh Metamorphics Leucogranite, guartz-feldspar-biotite gneiss, minor amphiboLite, gneiss, pegmatlte, migmatite, and mica schist. Host to mineraLised breccia pipe; contributes breccia fragments.

calc-siLicate

AGE: proterozoic EarLy STRUCTURAL FEATURES STRUC TURAL/STRA TIG RAPHIC INTERSECTIONS MAJOR:

Intrusive Contact,

IGNEOUS PROXIMITY MAJOR: Sub-VoLcanism(FeLsic porphyry) , VoLcanism(FeLsic) , AGE OF INTRUS ION: pa Laeozoi c Mi dd le Ca rboni fe rous AGF OF INTRUS ION: pa Laeo zoi c Ea r ly oevoni an AGE OF INTRUSION: paLaeozoic Late Silurian ~lETAMORPHISM:

RegionaL metamorphic grade is upper amphiboLite fades.

ALTERATION: Pervasive hydrothermaL aLteration is of restricted extent in t~e breccia pipe and outside the pipe is present onLy as haloes to sheeted veins. The rhyoLite and adjacent breccias are within the zone of intense phyLLic/argiLLic aLteration. Granodiorite and rhyoLite fragments are variabLy replaced by quartz, sericite, carbonate, pyrite and clay, and the breccia matrix is usualLy totaLLy repLaced. The intensity of aLteration decreases away from the rhyoLite breccia, grading into weak phyLLic/propyLitic alteration throughout most of the pipe. DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in feLsic voLcanic breccia pipe. STYLE: Discordant, MORPHOLOGY: pipe-Like , sheeted , AGE OF MINERALISATION: paLaeozoic Middle Carboniferous Dn1ENSIONS: OREBODY: Wises HilL STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH NATURE OF MINERALISATION: Disseminated, Free Mi LLing PRIMARY ORE: Breccia ,

m m m

NIN

AVE

MAX

650.0 350.0 300.0

Oxidised, primary,

...1IEII!lIIIIlII--------------------Miill-AGPS--~ ,~**

ID 5

*,~*

plIIlII-- MICROGRAPHIeS BUREAU -------------------1IIIIIIlIiII MINERALOGY: OREBODY: Kidston Sulphide ore (veins and infi lL): goLd, pyrite, minor sphaLerite, pyrrhotite, chalco~yrite, galena arsenopyrite molybdenite, : tetrahedrite. Sulphides typicalty replace carGonate and comprise less than 57. by voLume of the totaL rock. Native goLd occurs as free microscopic particLes with approximately 107. occurring in submicroscopic form in pyrite or arsenopYrite. Gangue (veins and infi Ll): quartz, calcite, ankerite, epidote, adularia. GENETIC CONTROLS: The Location of the breccia pipe is reLated to broad scaLe structural features and was apparentLy controlLed by the same magmatic and post magmatic processes involveCl in the deveLopment of the ring complexes. Fluid incLusions: the stockwork quartz veins and tourmaline breccia yielded similar homogenisation temperatures of 320-460 deg, peak 420 Cleg, and 250-480 deg, peak 400 deg, respectively. SaLinities for both dispLayed a bimodaL distribution at < 10 equivalent weight X NacL. Inclusions in the quartz breccia infi II and sheeted veins yielded lower, simiLar homogenisation temperatures, of 172-388 deg, with maxima at 200 deg and 370, and 200-400 deg, maximum 260-300 ceg, respectiveLy. Salinities for ooth were < 107. NaCl. The fluid inc lusion data indicate a depth of formation of < 2.5 km. GENETIC MODELS: Mustard (1986) proposed an epithermal model in which mineralisation and brecciation are directly related to massive release of voLati Les from the apex of a crystalLising feLsic ma~ma at shaLlow depth. i ) ~lagmatic fluiCls were concentrated ln a cupoLa of a major igneous mass and injected into the overlying rocks, forming quartz stockwork and tourmaLine breccia. i i ) Flui d overpressure resuLted in deve Lopment of uni di rectiona l solidification texture ("brain roc~') in the apex of the cupola. The fluid was a two phase fluid (250-480 deg, salinity 40-537. NaC L) coexisting with a gaseous fLuid of Low salinity (300-400 deg, 107. NaCL). iii) Magma crystallisation was accompanied by increase in fluid pressure till fluids were violently released into the cover rock, forming the breccia nipe. iv) Late, cooLer, mixed magmatic/meteoric fluids (200-400 deg, < 107. NaCl> were mobi lised by the intrusion of rhyolite porphyry dYKes and chanr.elLed throu~h the breccias, depositing auriferous quartz-carbonatesulphide cavity lnfilLing. permeabi Lity was greatest in the rhyolite breccia around the pipe margin. v) Conical sheeted extension fractures were formed, possibly. as a resuLt of magmatic resu~gence, and fi lled with precipitate from the same circulating fluids responsible for the breccia cement. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Kidston REGIONAL SETTING: PERMO-CARBONIFEROUS IGNEOUS PROVINCE From the Late-Carboniferous-Early permian much of north Queens land was the site of intrusion of granitic bathoLiths and Huption of extensive comaQmatic volcanics. The magmatic activity was not influenced by preVl0US tectonic boundaries and extended over the Cape York-Oriomo, Coen, Georgeto~1n and Anakie InLiers, the Hodgkinson, Drummond and Burdekin Basins, and the Lolworth-Ravenswood Block. he intrusions range in si ze from small plutons and ring compLexes to arge batholiths, and are dominantly granite, adamellite, anCl

T

-AGPS--....

.,..--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - -1lllIIIIIIllI gral'lodiorite. The voLcanics are dominantLy rhyodacitic ash flow tuffs whi c h occupy Large cau Ldron subs idence areas. ASSOCIATED MINERALISATION Abundant goLd mineralisation is associated with the permo-Carboniferous igneous roc ks. Hlstorical production has come mainLy from generaLly smaLL but high grade vein deposits associated with granitic to dioritic pLutons. Recent deveLopments have been of buLk-tonnage Low-grade disseminated orebodies associated with feLsic voLcanic and sub-voLcanic compLexes (e.g. Kidston, pajingo( Mount Leyshon, some Ravenswood, Far Fanning, Mount Success, Mount Wrlght, LoLworth, some Cape River). A second important type of Low-grade deposit is represented by the goLd skarn mineraLisation at Red Dome. GEOLOGICAL SETTING: KIDSTON Kidston Lies in the south centraL-eastern part of the Forsayth subprovince within a beLt of abundant Late paLaeozoic igneous activity. carboniferous feLsic extrusive rocks (NewcastLe Range VoLcanics) cover a vast area 1'1(\, "hwest of Kidston and are rimmed by faults forming cauLdron subs1cence areas. The Kidston gOld deposit is associated with a rhyoLite breccia pipe which cuts the contact between Einas Leigh Metamorphics and Oak River Granodiorite. The metamorphic/granite contact LocaLLy trends westnorthwest. The metamorphics comprise muLtipLy deformed and foLded schist, gneiss, amphiboLite, migmatite and quartzite representing the oLdest section of the metasedimentary sequence (Etheridge Group). The Oak River Granodiorite is a major phase of the Copperfield Batholith, a Large bathoLith of probabLe si Luro-Devonian age. In the deposit region it is intruded by a younger, marginaL phase, the Digger Creek Granite. The regionaL granite/metamorphic contact in part forms the northerly extensl0n of the Gi Lberton FauLt, a major regionaL northeasterLyscriking discontinuity which disrupts the overaLL northerLy trend of the metasedlmentary sequence to the north. South of the fauLt structural directions are dOffi1nantLy northeast. The EinasLeigh Metamorphics are intruded on the southern side of the G1Lberton FauLt by two major Carboniferous igneous compLexes. The Lochaber Ring compLex and the Bagstowe Ring Dyke CompLex comprise cores of adameLlite or microadameLL,te surrounded by ring dykes of andesitic to rhyoLitic composition. The comp Lexes are eLongate aLong coLLinear northeast axes. A rhyoLite dyke swarm that emanates from the Lochaber Ring complex intersects the Kidston breccia pipe. A gravity Low foLLows the dyke swarm from the compLex through the pipe, consistent with the possibLe presence of an igneous body at depth. Some of the rhyoLite dykes cut the pipe margin, some are restricted to the pipe, and som~ have been brecciated. The Kidston breccia pipe is ovoid in pLan with axiaL dimensions 1300 m X 920 m; the pipe is eLongate in a north-easterLy direction. pipe margins dip inwards at 80 deg. The pipe comprises fragments of granodiorite, metamorphic rocks and rhyoLite in a matrix of fine-grained « 1 mm) fragments of simi Lar lithologies, and ;nfi lled by quartz-carbonate breccia cement. The pipe is LithoLogicalLy and structlraLLy zoned, from the margin:i) outer zone: monomict (granodiorite or metamorpnic rock) breccia reflecti ng country rock L1thoLogy; ii) inner zone: bimictic breccia, fr,rmed from mixing of rhyoLite fragments with monomictic breccia; iii> centraL zone: polymictic brec;ia, formed from mixing of granodiorite, metamorphic and rhyolite fragments. Fragment size and fragment:matrix latio decrease inwards as degree of mixlng and verticaL transportation 'ncreases. The outer zone is rimmed by a zone 1'1-20 m wide of shatter or crackle

-AGPS---sI

J!llIIIBII-- MICROGRAPHIeS

BUREAU

-----I-------------1IIlIIIl-Bl

breccia in the country rock. The pipe is asymmetrical in zone development--the inner zone is best developed in the northeastern and southwestern sectors of the pipe. An area of rhyolite breccia occurs within the bimictic breccia in the southwestern sector and is broadly coincident with zones of pre-breccia features stock-work quartz veining, tourmaline breccia and "brain ,"ock". The rhyolite breccia coincides witn the maximum intensity of hydrothe rma l a lte ration. The pipe marQin is overlapped by sets of tangential sheeted quartzcarbonate velns. The veins fill subparallel fractures which dip steeply into the pipe but at a shallower ang le than the pipe margin. The veins average 10 m~ in thickness and occur at a density of up to 10 per metre. The s heeted vei ns are a lso best deve loped in the southwes t sec to r ,. Gold mineralisation occurs in association with sulphides which accompany quartz-carbonate in the sheeted veins and breccia cavity infi ll. Gold grades are generally higher in the veins than in the breccia infi ll. cavity infill mineralisation is best developed in the rhyolite breccias because of the higher permeabi lity of rhyolite breccia and consequent higher proportion of hydrothermal matrix. The ore zones occur in a semi-continuous band near the margin of the pipe. Best ore development is centred on the area of rhYolite breccia in the south west sector = Wises Hi ll, the site of current open ~ut mining. REFERENC ES: Andrew A.S. , Baker E.M. , 1987 The nature and origin of the ore-forming fluid in the Kidston gold deposit, north Queens land. IN Proceedings, paci fic Rim Congress 87, Go ld Coast, Queens land, August 1987. Aus IMM 1v p13-16 Bain J.H.C. , Withnall 1."1. , 1980 Mineral deposits of the Georgetown region, northeast Queensland. IN Henderson R.A. & Stephenson P.J. (eos) - The geology and geophysics of northeastern Australia. Geological Society of Australia. Queensland Division 1v p129-148 Baker E.M. , 1987 The geoloQY, alteration and mineralisation of the Kidston breccia pipe. ph.D thesls. James Cook University, North Queens land. Unpublished 1v Baker E.M. , 1987 Brecciation mineralization and alteration of the Kidston gold deposit. IN Proceedings, pacific Rim Congress 87, Gold Coast, Queensland, August 1987. Aus IM~l 1v p29-33 Bartrum J. , plyley W.F. , 1986 Some metallurgical aspects of the Kidston gold mine. IN Gold exploration ana development, north Queens land. AusIM~1 Conference, Charters Towers, August 1986. ExtE'nded abstracts. AusIMM 1v p1 0 ~-112

*** LOS ***

-AGPS---.II

£lIIIZIIlI--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -.... Branch C.O. , 1959 Progress report on Upper PaLaeozoic intrusions controLLed by ring fractures near Kidston, north Queens Land. Bureau of MineraL Resources, AustraLia. Record 59/104 Branch c.o. , 1966 VoLcanic cauL~rons, ring cOMpLexes, and associated granites of the Georgetowfl 1nl ier, Queens Land. Bureau Miner~L Resources, AustraLia. 8uLLetin 76 CoLdham J .C. , 1934 Report on the Oaks go Ldfie Ld. Geo Logi ca L Survey of Queens Land. CR 1022

Report

Graylin R.K. , 1981 The geoLogy of the Kidston breccia compLex. M.Sc. thesis. James Cook University, North Queens Land. unpubLished 1v Jensen H.I. , 1920 The Kidston goLdfieLd. Queens Land Government Mi ni ng Journa L 21 P186-192 Knight D.A. , Medina V.G. , 1986 Ki dston go Ld mi ne sta rtup_ MineraLs and MetallurgicaL processing 31(1) P45-49 Marks E.O. , 1911 The Oaks and eastern portion of the Etheridge goLdfieLd. GeoLogicaL Survey of QueensLand. pubLication 234 Mi ni ng Magazi ne. , 1986 Kidston goLd mine, AustraLia. Mi ni ng Magazi ne 154(1) P16-21 JltJstard H. , 1984 Brecciation and mineraLisation at the Kidston goLd deposit, north Queens Land. IN Geoscience in the deveLopment of naturaL resources. AustraLian GeoLogicaL Convention, Sydney 1984. Abstracts. GeoLogicaL Society of AustraLia 12 P394-396

7th

Mustard H. , 1986 GeoLogy and genesis of the Kidston goLd deposit, QueensLand, AustraLia. IN MacaonaLd A.J.(ed) - GoLd '86. proceedings of symposium, Toronto, Canada, september-October 1986. KonsuLt InternationaL Inc., WiLLowdaLe, Ontario, Canada 1v p404-415 Mustard H. , 1983 Breccia forming processes at the Kidston goLd deposit. thesis. James Cook University, North QueensLand. unpubLished 1v

...

***

f05

8.Sc. (Hons)

***

--------------------~-AGPS--

..

. . . - - - MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - -..... Needham R. , 1 985 The Kidston goLd mine: a development cha Llenge of a low grade deposit. IN AusIMM Annual Conference, Southern Queensland, Brisbane, July 1985. AusIMM. conference Series 14 P121-128 Queensland Government Mining J , 1985 Kidston on stream: Queens land premier opens Australia's biggest gold producer. Queens land Gove rnment Mi ni ng Journa l 86(1001) P111-113 1 912 Rands W. H. The Oaks Rush go ldfi e ld. Queensland Government Mining Journal 13 p544-548 Reid J .H. f 1932 The Oaks gOLdfield, Kidston. Queens Land Government Mi ni ng Journa l XXXIII P287-288 Turner A.R. , 1976 GeoLogy and mineralisation of the Kidston breccia pipe, NE Queensland. Anaconca Australia Inc. Unpublished Report 1v Wilson G.I. , Lewis R.W. , GaLlo J.B. , TuLlemans F.J. , 1986 The geology of the Kidston gold mine. IN Berkman D.A.(ed) - 13th CMMI Congress, singapore, May 1986. pubLications Volume 2. Geology and exp Loration. 13th Congress of Council of Mining & MetallurgicaL Institutions & AusIMM 13(2) P235-242 Wils on G. I • , 1 987 The Kidston goLd mine. IN Herbert H.K.(ed) - Gold in Queensland. proceedings of one-day symposium, university of QueensLand, June 1984. University of Queensland. Department of Geology. papers 12(1) P84 Wilson G.I. , Lewis R.W. , GaLlo J .B. , TuLlemans F.J. , 1986 The geology of the Kidston gold mine. IN Berkman D.A.(ed) - 13th CMMI Congress, Singapore, May 1986. publications Volume 2. Geology and exp Loration. 13th Congress of Counci l of Mini ng & Meta llurgicaL Institutions & AusIMM 13 (2) P235-242 0000000000000000000000000000000000000000

...

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N05

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..

....---MICROGRAPHICS B U R E A U - - - - . . - - - - - - -...........- - -....--~ DEPOSIT:

13

PERCYV ILLE

DEPOSIT IDENTIFICATION:

----------------------

SYNONYMS: Percy River, PRINCIPAL COMMODITIES: AU , Ag , Cu , MINES: pe rcy River ,

pe rcyv i lle ,

OREBODIES: Homeward Bound, Mount Hogan ,

Oakvi Lle ,

percy River, percyvi lle ,

GROUP: Etheridge Group COMMENTS: see Deposit No. 10 Georgetown for regional setting of Georljetown Inlier, Forsayth subprovince, and Etheridae group. Record covers mnor deposits in 3 separated areas: Oakvi lle, perCYV1 lle, and Mount Hogan. LOCATION: LATITUDE: 19 1 250K SHEET: SE54 16

LONGITUDE: 143 46 100K SHEET: 7659

ADMINISTRATIVE SUBDIV ISION: MINING DISTICT: Georgetown MINING FIELD: Etheridge LOCALITY: DEVELOPMENT HISTORY:

-------------------DISCOVERY METHOD P rospec ti ng

DISCOVERY YEAR 1869 OPERATING STATUS AT 1987 MINE Percy River percyvi lle

STATUS OJle rati ng Histori ca l

MINING ~IETHOD Alluvial Alluv i a l

COMPANIES: OREBODY: Percy River COMMENTS

PRESENT OPERATORS: Sandhurst Mining N L.

***

..._ _-.:

P.06

,~**

- -....--~----~-AGPS--IIIII

...- - MICROGRAPHIeS BUREAU-------~---~----lI'ISIlI--~ EQUITY 85.00 15.00

PRESENT OWNERS: Sandhurst Mining N L. Tamsi n Pty Ltd.

r-

CDMMENTS

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 1,500

GOLD(kg) 590

RECOVERED GRADE(g/t) 393.33

COM~lENTS

MAIN PRODUCTION PERIODS: 1890-1899 , RESOURCES: DATE

ORE('OOOt)

GRADE(g/t)

GOLD(kg)

CLASSIFICATION

Dec 1987

2,730

0.3

791

Economic Demonstrated RecoverabLe

Dec 1987

13,000

0.2

3,120

Economi c Inferred

In-Situ

aLv

a Lv

percy River. Units are: OREC'OOO cubic ~) "G~AREC9 /cubi c m)

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: SLOCK: PROVINCE: Georgetown InLier SUS-PROV INCE: Forsayth Subp rovi nee HOST ROCKS: Digger Creek Granite Muscovite Leucogranite. Host to Lode-type mi ne ra Li sation at percyvi LLe. Eil1as Leigh Metamorphics si,·.tite gneiss, caLc-silicate Qneiss, amphiboLite, migmatite, schist, quartzite. ROllf pendants of metamorphics ln granite are host to some mineraLisation at Per,vvi LLe. Mount Hogan Granite biotite Qranite. Host to vein mineraLlSation within hydrothermally aLtered zones at Mount Hogan. porp~yritic

Robin Hood Granodiorite HornbLende-biotite granodiorite. Host to vein mineraLisation in PLunger).

shear

zones

at

OakviLLe

(including

JUbilee

AGE: proterozoic EarLy

...

***

S06

***

--------------------~-AGPS--

.

. - - - MICROGRAPHIeS BUREAU -~-_.-_------------......,; STRUCTURAL FEATURES MAJOR: Fracturing ( SIGNIFICANT: shearlng , STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact , IGNEOUS PROXIMITY MAJOR: pLutonism(Granite) , Sub-VoLcanism(Felsic porphyry) , SIGNIFICANT: sub-VoLcanismCFe Lsic porphyry) , AGE OF INTRUSION: paLaeozoic permian AGE OF INTRUSION: pa Laeozoic Carboni ferous AGE OF INTRUSION: proterozoic MiddLe METAMORPHISM: Regional metamorphic grade is amphibolite facies. ALTERATION: ChLorite-epidote aLteration is associated with mineraLisation. ~lineralisation is associated with zones of intense chLorite-sericiteepidote aLteration which dip shaLlowly outwards from the granite p luton and grade into una l te red g rani te. DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. Auriferous quartz veins in metasediments adjacent to granitoid. STYLE: Discordant , stratabound , AGE OF MINERALISATION: paLaeozoic SiLurian AGE OF MINERALISATION: proterozoic MiddLe DIMENS IONS: OREBODY: Mount Hogan TRUE WIDTH OREBODY: percyvi lle STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH

cm )

m)

cm )

m)

MIN

AVE

MAX 60.0

MIN

AVE

20.0

60.0

MAX 300.0 120.0 150.0

NATURE OF MINERALISATION: Oxidised, primary, PRIMARY ORE: Lode (Alteration Zone) , Vein (Reef) , MINERALOGY: OREBODY: Mount Hogan sulphide ore: goLd (and si lver) mostly occur associated with pyrite

----------------------~-AGPS--IIIIII

JiIiIIlSl--MICROGRAPHICS BUREAU

--------------------1IIIIIIlIIlIIII

and base-meta L suLphides in vughy white quartz veins. SuLphides inc Lude chaLcopyrite, gaLena, sphaLerite, pyrrhotite and tetrahedrite. Accessory mineraLs: moLybdenite, fluorite, torbernite, metatorbernite, pitchbLende, phospuraryLite, ?uraninite. OREBODY: percyviLLe SuLphide ore: chaLcopyrite and gaLena in quartz. Oxide ore: cuprite, maLachite, azurite. GENETIC CONTRO LS: ~lount Hogan: the orientation of quartz veins and a Lteration zones and their restriction to granite suggest that these features were controLLed by a sheeted fracture system near the roof of the p Luton. GENETIC MODELS: percyvi LLe: the Robin Hood Granodiorite may be the source of goLd. Mount Hogan: HydrothermaL fLuids, possibLy introduced by the rhyoLite stock or reLated body couLd have been preferentiaLLy channeLLed into a fracture system in the nearby granite, resuLting in aLteration and mineraLisation. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Mount Hogan The Mount Hogan ~o Ld depos i t di ffe rs from the gene ra L p atte rn in the Etherid~e fieLd 1n the shaLLow dip of the Lodes, the extensive waLLrock aLterat10n and the association of uranium, fLuorine and moLybdenum mineraLs. MineraLisation comprises thin discontinuous en echeLon quartz veins within braod zones (6-15 In wide, maximum 30 m) of intensive hydrothermaL aLteration within biotite granite. A Large mass of rhyoLite intrudes the metamorphics to the south. OREBODY: percyvi LLe At Percyvi LLe, MiddLe Proterozoic muscovite and pegmatite granite (Digger Creek Granite) are intruded by si Lurian granitoid (Robin Hood Granodiorite). MineraLisation occurs in both granite and metamorphics. ?permo-Carbnni ferous rhyoLite dykes are common and are associated with some of the goLd mineraLisation. REFERENC ES: Armstrong K.J. , 1975 Soil sampLing of the Jubilee PLunger goLd prospect, Forsayth, north Queens Land. Bureau of MineraL Resources, AustraLia. Record 75/ 68 Bain J.H.C. , 1976 A preLiminary investigation of the nature, origin, and economic potentiaL of the Jubi Lee PLunger goLd deposit, centraL Georgetown InLier, north Queens Land. Bureau of MineraL Resources, AustraLia. Record 76/ 77 Bain J.H.C. , 1980 Some new ideas on the age and origin of the Etheridge GoLdfieLd, QueensLand, and their expLoration impLications in the AusIMM Conference, New Ze a La nd, May 1 980. AusIMM 1v P53-66

-AGPS

IIIIlZl-----------.-.riII!

..._ _ MICROGRAPHIeS BUREAU

Bain J.H.C. , withnaLl I.W. , 1980 Mi nera L deposi ts of the Georgetown region, northeast Queens Land. IN Henderson R.A. & stephen~on p.J. (eds) - The geoLogy and geophysics of northeastern AustraLia. GeoLogicaL Society of AustraLia. QueensLand Division 1v p129-148 Bain J.H.C. , oversby B.S. , Mackenzie D.E. , Moffat P. WithnaLL I.W. , 1985 GeoLogy of the Georgetown region, QueensLand, 1:250000 geoLogicaL speciaL map. 1st edition. Bureau MineraL Resources, AustraLia & GeoLogicaL Survey of QLd 1v BainJ.H.C. ,1979 A study of the Jubi Lee PLunger goLd-s'j Lver-base metaLs deposit, Etheridge goLdfieLd( north QueensLand. M.Sc. thesis. James COOK University, North Queens Land. Unpublished 1v Bain J.H.C. , oversby B.S. , WithnaLL I.W. , Mackenzie D.E. , 1984 MineraL deposits of the Georgetown region, Queens Land, 1 :250 000 scaLe map. Bureau MineraL Resources, AustraLia 1v Bain J.H.C. , WithnaLL I.W. , 1985 MineraL deposits of the Georgetown region, Queens land: production figures and bi b Li og rap hy. Bureau of MineraL Resources, Austra Lia. Record 85/ 10 Ball L.C. , 1914 Etheridge mineral field. potentiaLities of the southern port'ion. Queens land Government Mi ni ng Journa l 15 P174-184; p239-245 BallL.C. ,1915 The Etheridge mineral fieLd (the potentiaLities of the southern portion). Geological Survey of Queensland. Publication 245 Cameron W. E. , 1900 The Etheridge and Gilbert goldfieLds. GeoLogical Survey of Queensland. pubLication 151 Cameron W.E. , 1901 Etheridge and Gi Lbet·t goLdfields. Queens land Government Mi ni ng Journa l 2 P22-27 P65-69 P113-114 Cameron W.E. , 1908 The Etheridge goLdfie '.d. Queens Land Government Hi ni ng Journa l 9 P340-348 Geraghty T.R. , 1898 Map of the Etheridge goldfield. scaLe 1:63360. GeoLogical Survey of Queensland. pubLication 137

....

..

*ir* E06

,~*,~

-=------------------.~-AGPS

--_.. .

..---MICROGRAPHICS

BUREAU------------------~

Maj or J .A. , WiLson O.R. , 1978 GeophysicaL surveys at the Jubi Lee pLunger goLd deposit, Georgetol~n In Lie r, Queens Land, 1974-1976. Bureau of MineraL Resources, AustraLia. Record 78/ 60 O'Rourke P.J. , BenneLL M.R. , 1977 The Mount Hogan goLd, si Lver and uranium prospect north Queens Land. QueensLand Government Mining JournaL 78(911) P424-433 Rossiter A.G. , 1980 JubiLee pLunger Au deposit, Georgetown InLier, QLd. IN Butt C.R.M., smith R.E. (eds) - ConceptuaL modeLs in expLoration geochemistry, 4. (Reprinted from JournaL of GeochemicaL ExpLoratio;, 12(2/3).) Association of EXPLoration Geochemists. speciaL PubLication 8 P234-237 WaLL LoN. , WithnaLL I.W. , 1975 Georgetown InLier - mineraLization. IN Knight c.L.(ed) - Economic geo Logy of Austra Li a and papua New Gui nea - 1. Meta Ls. AUS IMM. Mo nog rap h Se ri es 5 P516-518 White O.A. , 1965 The geoLogy of the Georgetown-C Larke River area, North Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 71 WithnaLLI.W. ,1981 contributed discussion to "some new ideas on the age and origin of the Etheridge GoLdfieLd, QueensLand~ and their expLoration impLications", by J.C. Bain. (Proceedings No.27r, March 1981). AusIMM. proceedings 279 p43-45 WithnaLL I.W. , 1981 Mines and mineraL deposits of the Gi Lberton 1 :100 000 sheet area. GeoLogicaL survey of QueensLand. pubLication 370 Withna LL I.W. , 1976 Summary of mineraL expLoration in the Georgetown area. Queens Land Government Mi ning Journa L 77 P583-599 WithnaLl I.W. , oversby B.S. 6 Bain J.H.C. , Baker E.M. , 1980 GeoLogy of the GiLberton 1 :100 00 sheet area (7659), north Queens Land: data record. Bureau of MineraL Resources, AustraLia. Record 80/2 0000000000000000000000000000000000000000

JI-.

~

***

F06

,h~*

..

~_AGPS--

.....--MICROGRAPHICS

DEPOSIT:

14

BUREAU-----------------.--...

GILBERTON

DEPOSIT IDENTIFICATION: SYNONYMS: Gi Lbert River, PRINCIPAL COMMODITIES: AU , MINES: commissioners Hi LL , Gi Lbert River, Gi Lberton , OREBODIES: commissioners Hi LL , Gi Lbert River, Gi Lberton , GROUP: Etheridge Group COMMENTS:

See Deposit No.

10 Georgetown for regionaL setting of Georgetown InLier, Forsayth subprovince, and Etheridge group. LOCATION: LA TITUDE: 19 15 250K SHEET: SE54 16

LONG ITUDE: 143 40 100K SHEET: 7659

ADMINISTRATIVE SUB DIV IS ION: MINING DISTlCT: Georgetown MINING FIELD: Ethe ri dge LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1869 OPERATING STATUS AT 1987 MINE Commissioners HilL GiLbert River Gi Lberton

STATUS HistoricaL

MINING METHOD unde rg round

Operating HistoricaL

A LLuv i a L ALLuv i a L

CO~lPANIES: OREBODY: GiLbert River PRESENT OPERATORS: Portman ~lining Ltd.

....

~

COMflENTS

*** G06

,~**

~-AGPS--alI

-.a---_a.-----.

1.QII l!IIII- -MICR OGR APHI CS BURE AU PRESENT OW NERS: Portman Hi ni ng Ltd.

~-_ _

EQUITY Y. 100.00

COMHENTS

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.198 6): ORECt):

GOLDCkg) 4,900

RECOVERED GRADEC9/t) 0.00

CO~lMENTS

Ore tonnage s and recovere d grade not appLicab Le to aLLuvia L deposit s. Zero figures resuLt from program ca lcu Lat, ons.

MAIN PRODUCTION PERIODS: 1869-18 93 , 1984- , RESOURCES: DATE

OREC'OOOt)

GRADEC 9/t)

GOLDC kg)

CLASSIF ICATION

Dec 1987

1,000

0.4

350

Economi c Demons trated Recovera bLe

a Lv

Units are: OREC'OOO cubic m) GRADEC g/cubic m)

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: PROVINCE: Georgeto wn InLier SUB-PROVINCE: Forsayt h subprov ince HOST ROCKS: DanieL Creek Formati on CRobert son River p) Grey sLightl y carbona ceous metasiL tstone Subgrou and sLate. MineraL isation occurre d in thin quartz veins in tension

gashes.

Bernec ke r Creek Formati on CaLcare ous sandsto ne and si Ltstone. Host to minor vein mineraL isation. Dead Horse Metabas a Lt,: cobbo Ld Metado Leri te Metabas aLt, metado Lerite. As in Berneck er Creek Formati on. AGE: protero zoic EarLy STRUCTURAL FEATURES SIGNIFIC ANT: Fractur ing ,

-AG PS --.- I

fiDlIllll!IZIIIIDlBIIiIIII

MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - -......

S TRUCTURALlS TRA TIGRAPHIC INTERSECTIONS MAJOR: stratigraphic BoundarY, IGNEOUS PROXIMITY SIGNIFICANT: plutonism(Ultramafic) , Volcanism(Mafic) , METAMORPHISM: Regional metamorphic grade is low grade (slate). ALTERATION: No obvious wall-rock alteration present. DEPOSIT CHARACTERISTICS: TYPES: Aurifer.)lJs quartz veins in metasediments adj acent to granitoid. Alluvia l. STYLE: Discordant, AGE OF M.INEr-,ILISATION: palaeozoic permian AGE OF MINERALISATION: palaeozoic carboniferous AGE OF ~lINERALISATION:

proterozoic Middle

AGE OF ~lINERALISATION:

Mesozoic

DH1ENSIONS: OREBODY: Gi lbe rton TRUE WIDTH

( cm'

NATURE OF MINERALISATION: Fre e Mi lli ng , PRIMARY ORE: Vein (Reef) , SECONDARY ORE: Detri ta l (A lluv i a l)

NIN 5.0

AVE

MAX 50.0

,

~lINERALOGY:

OREBODY: Gilberton Sulphide ore: quartz, gold pyrite, si lver, subordinate galena. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Gi lberton The stratigraphy in the southern part of the Forsayth Subprovince is disrupted by the major northeast-striking Gilberton Fault. North of the fault, the Etheridge Group is rel?resentec mainly by low grade sediments of the Robertson RlVer Subgroup in the southwest, grading northeastwards to greenschi st facies, and amphi bo lite facies Ei nas leigh Metamorphi cs in the northeast. The metamorphics are intruded by several discrete Proterozoic p lutons, but the main intrusive rocks are much larger Siluro-Devonian batholitn. The Siluro-Devonian Robin Hood Granodiorite was emplaced on the northeast side of the s late/schlst facies boundary. In the northeastern

-AGPS--..mD

flIDlIB-- MICROGRAPHIeS BUREAU--------------------. part of the region the Einas Leigh Metamorphics are intruded by the oak River Granodiorite of the CopperfieLd 8athoLith. South of the Gi Lberton FauLt, northeasterLy-trending EinasLeigh Metamorphics are intruded by the carboni ferous Bagstowe Ring comp Lex. GoLd mineraLisation in the southern part of the Forsayth Subprovince occurs aLmost exclusively north of the GiLberton Fault, and in a wider vari ety of geo logica l setti ngs than in the Georgetown-Forsayth area. Deposits (at Gi lberton, Mount Hogan, Percyvi lle and Robin Hood) occur in post-folding fissures in metasedlments, metabasaLt, metadoLerite, granitoid, and rarely metarhyoLite. Gi Lberton gold occured in folded sLightLy carbonaceous metasi Ltstone and s Late (Dame l Creek Formation) of the Robertson River Subgroup. Metabasic extrusive and intrusive rocks are abundant in the mineralised area. In the centra L part of the area the reefs were confined to two zones trending east-northeast and east-southeast respectively, which may represent subsurface shears or flexures which grade upwards into en echelon tension gashes. The Comstock Lode was a breccia zone which may represent a shear which did reach the surface. REFERENC ES: BainJ.H.C. ,1980 Some new ideas on the age and origin of the Etheridge GoLdfieLd, Queensland, and their expLoration impLications in the AusIMM Conference, New zea land, May 1980. AusIMM 1v P53-66 Bain J.H.C. , WithnaLL I.W. , 1980 MineraL deposits of the Georgetown region, northeast QueensLand. IN Henderson R.A. & Stephenson p.J. (eds) - The geoLogy and geophysics of northeastern AustraLia. GeoLogicaL society of Australia. Queensland Division 1v P129-148 Bain J .H.C. , oversby 8.5. , Mackenzie D.E. , Moffat p. WithnaLL I.W. , 1985 Geology of the Georgetown region, Queensland, 1:250 000 geoLogicaL speciaL map. 1st edition. BureaU MineraL Resources, AustraLia & GeoLogical Survey of QLd 1v Bain J .H.C. , oversby 8.5. , WithnaLL I.W. , ~lackenzie D.E. , 1984 MineraL deposits of the Georgetown region, Queensland, 1:250 000 scaLe map. Bureau MineraL Resources, AustraLia 1v Bain J .H.C. , withnalL I.W. , 1985 Minera L deposits of the Georgetown region, Queens Land: production figures and bibliography. BureaU of MineraL Resources, AustraLia. Record 85/ 10 BaLL L.C. , 1914 Etheridge mineraL fieLd. potentiaLities of the southern portion. QueensLand Government Mining JournaL 15 P174-184; P239-245

11limam

..-

~-AGPS

_ _.e

p!IllIl_ _

MICROGRAPHICS BUREAU

1lIIBlIII

BaLL L.C. , 1915 The Etheridge mineraL fieLd (the potentiaLities of the southern portion). GeoLogicaL Survey of Queens Land. pubLication 245 Cameron I4.E. , 1900 The Ethe ri dge and GiLbe rt go Ldfi e Lds. GeoLogicaL Survey of QueensLand. pubLication 151 CameronW.E. ,1901 Etheridge and GiLbert goLdfieLds. Queens Land Government Mi ni ng Journa L 2 p22-27 p65-69 P113-114 Cameron W.E. , 1908 The Ethe ri dge go Ldfi e Ld. Queens Land Government Mi ni ng Journa L 9 p340-348 Geraghty T.R. , 1898 Map of the Etheridge goLdfieLd. ScaLe 1:63 360. GeoLogicaL Survey of QueensLand. pubLication 137 WaLL L.N. , withnaLL 1.14. , 1975 Georgetown InLier - mineraLization. IN Knight C.L.(ed) - Economic geoLogy of AustraLia and Papua New Guinea - 1. MetaLs. AusIMM. Monograph Series 5 p516-518 White D.A. , 1965 The geo Logy of the Georgetown-C Larke River area, North Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 71 WithnaLL 1.14. , 1981 Contributed discussion to "some new ideas on the age and origin of the Etheridge GoLdfieLd, QueensLandt. and their expLoration impLications", by J .C. Bain. (Proceedings No.27r, March 1981). AusIMM. proceedings 279 P43-45 WithnaLL 1.14. , 1981 Mines and mineraL deposits of the Gi Lberton 1:100 000 sheet area. GeoLogicaL Survey of Queens Land. pubLication 370 WithnaLL 1.14. , 1976 Summary of mineraL expLoration in the Georgeto~1n area. QueensLand Government Mining JournaL 77 P583-599 14ithnaLL 1.14. , oversby B.S· 6 Bain J.H.C. , Baker E.~l. , 1980 GeoLogy of the GiLberton 1:100 00 sheet area (7659), north QueensLand: data record. Bureau of MineraL Resources, AustraLia. Record 80/ 2 0000000000000000000000000000000000000000

h

*** K06

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-AGPS--.-II

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MICROGRAPHIeS

DEPOS IT:

15

BUREAU----------·---------....

CLONCURRY

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: Au , Ag , Cu , MINES: C Loncurry , Gi Lded Rose, Mount Freda , OREBODIES: Answer, CLoncurry , Duchess, Gi Lded Rose, Hampden, Mount ELLiott , Mount Freda , Mount Mascotte , Mount Mcnamara , pumpkin GuLLy, SoLdiers Cap, Treke Lano , GROUP: cLoncurry Group COMMENTS: Inc Ludes regiona L setting of Mount Isa InLier, Eastern FoLd BeLt, and CLoncurry group_ Record covers cLoncurry GoLd and MineraL FieLd, which is distributed over an area 50km x 40km south and east of C Loncurry. LOCATION: LATITUDE: 20 42 250K SHEET: SF54 2

LONGITUDE: 140 43 100K SHEET: 7056

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: cLoncurry MINING FIELD: CLoncurry LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD Prospec ti ng

DISCOVERY YEAR 1867 OPERATING STATUS AT 1987 MINE

C Loncurry

Gi Lded Rose Gi Lded Rose Mount Freda C Loncurry

STATUS HistoricaL HistoricaL Possi b Le possi b Le Operati ng

~lINING METHOD Underg round Unde rg round Open-Cut Open-Cut A Lluv i a L

COMPANIES: OREBODY: CLoncurry

*** LO 6

*1,,~

-AGPS----

paIII-- MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - - . COMMENTS

PRESENT OPERATORS: A.U.R. N L. EQUITY 50.00

PRESENT OWNERS: A.U.R. N L.

r.

COMMENTS

ORE80DY: Gilded Rose COMMENTS

PRESENT OPERATORS: Diversified Mineral Resources N L. EQUITY 25.00 75.00

PRESENT OWNERS: Central Victorian Gold Mines N L. Diversified Mineral Resources N L.

r.

COMMENTS

ORE80DY: Mount Freda COMMENTS

PRESENT OPERATORS: Diversified Mineral Resources N L. EQUITY 10.00 90 .00

PRESENT OWNERS: Central Victorian Gold Mines N L. Diversified Mineral Resources N L.

r.

COMMENTS

PRODUCTION: CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 2,469,297

GOLD(kg) 3,174

RECOVERED GRADE(g/t) 1.28

COMMENTS

MAIN PRODUCTION PERIODS: 1867-1900 , 1906-1918, (1927-1940) , 1987- , RESOURCES: DATE

ORE (' OOOt)

June 1987 280 June 1987 300

GRADE(g/t)

GOLD(kg)

CLASSIFICATION

5.5 3.5

1,540 1,050

Economic Demonstrated In-Situ Economic Demonstrated In-Situ

o/c o/c

Gi lded Rose Mount Freda

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: PROVINCE: Mount Isa Inlier SUB-PROVINCE: Eastern Fold Belt HOST ROCKS: Soldiers Cap Group Mica schist, phyllite,

metagreywacke;

feldspathic

quartzite;

metabasalt,

*** M06 '1:**

....- - - - - - - - - - - - - I - - - - - - - U i I D - A G P S - -...

,-IBJIIE_ MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - . - . metasi Ltstone; moinor metarhyoLite, pegmatite, banded iron formation, feLsic metavo Lcani cs. GoLd mineraLisation occurred in shear-and fauLt-controLLed vein copper deposits ln quartzi te and metabasa Lt. Core LLa Formation Banded caLc-siLicate rocks, mafic and feLsic metavoLcanics, metasiLtstone, marbLe, caLc-si Licate breccia, phyLLite, schist, quartzite, gneiss, sLate, sandstone, shaLe. GoLd mineraLisation occurred in shear-and fauLt-controLLed vein copper deposits in high grade caLc-ciLicates. Ku ri da La Formati on Mica schist, metagreywacke, bLack sLate, phyLLite, meta-arkose, quartzite; minor banded caLc-ci Licates, banded iron formation, mafic metavoLcanics. GoLd mineraLisation occurred in shear- and fauLt-controLled vein copper deposits in hi g h grade metasediments. AGE: proterozoic Middle STRUCTURAL FEATURES MAJOR: Faulting, Fracturing, Shearing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY MAJOR: PlutonismCDoLerite) , SIGNIFICANT: plutonismCDolerite) , plutonismCGranite) , AGE OF INTRUSION: proterozoic Middle ~lETAMORPHISM:

Regional metamorphic grade is amphiboLite facies.

ALTERA TION: The shcist which forms the reef walls is commonLy garnetiferous or sericitic. DEPOSIT CHARACTERISTICS: TYPES: Metamorphic auriferous copper-gold veins in metasediments adj acent to mafic igneous rocks. ALluvi a l. Metamorphic auriferous quartz veins in high grade metasediments. STYLE: Discordant, stratabound , AGE OF MINERALISATION: Proterozoic Middle DIMENS IONS: OREBODY: Cloncurry DEPTH OXIDATION OREBODY: Gllded Rose

Cm)

MIN

AVE

MIN

AVE

30.0

MAX

100.0 MAX

***

N06

***

--------------~~=.-_----~li~-AGPS--

... 11

..

.---M ICR OGR APH ICS STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION OREBO DY: Hampde n

m ) cm ) m ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION OREBODY: Mount ELL iott

m m m m

TRUE WIDTH STRIKE LENGTH VERTICAL DEPTH OREBODY: Heke Lano

cm ) m ) m )

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION

m ) cm ) ( m ) ( m ) ( (

BU RE AU --- --- --- --- --- --- ---..... 30.0 50.0

MIN

AVE

1.0 107.0 MIN

AVE

MIN

AVE

15.0 35.0

60.0

135.0 50.0 MAX

1100.0 12.0 210.0 MAX

90.0 100.0 170.0 MAX

107.0 25.0 263.0

NATURE OF MINERALISATION: OXidis ed, primarY , ~RIMARY ORE: Vein (Reef) , MINERALOGY: ORE80DY: cLoncur ry Oxide Zone (copper -goLd-v eins): copper carbona te and oxides, viz: maLach ite, chaLco cite, cuprite (with "ti Le ore"), chrysoco LLa, tenorit e, azurite , coveLL ite, native copper, chalcan thite (and brochan tite), tetrahe drite, atacami te, and dioptas e. Gangue: Quartz and calcite (or dolomit e or both) are abundan t gangue mineral s in the copper deposit s, but by far the most siderit e, kaolin, chlorit e, hematit e, sericit e, hornble nde, talc, biotite , tremoli teactinol ite, scapoli te, magnet ite, diopsid e, augite, selenit e, tourmal ine, fluorite , apatite , psi lomelan e, barytes , epidote , garnet, and sphene also occur. Jasper and limonit ic gossan commonly occur in the leached outcrop s. ORE80DY: Gilded Rose Sulphid e zone: gold, pyrite. OREBODY: Hampden Sulphid e zone: chalcop yrite, marcas ite, pyrite. Oxide zone: malach ite, chrysoc olla, tenorit e, chalcoc ite. Gangue: quartz, kaolin. ORE80DY: Mount Elliott Sulphid e zone: chalcop yrite( pyrite, magnet ite, iJyrrho tite. Oxide zone: malach ite, cuprlte , lesser amounts of tenorit e, azurite , chrysoc olla, native COiJper. Gangu~: calcite , diopsid e, scapoli te, gypsum, apatite , sphene, prehm te. OREBODY: Treke lano Sulphid e zone: chalcop yrite, pyrite/m arcasite . Gangue (sulphid e zone): calcite . Oxide zone: chalcoc ite, malachit~, chrysoc olla, tenorit e. GENETIC CONTROLS: control s are structu ral and litholog ical. Structu ral - on a regiona l scale, vein copper deposit s are distribu ted in broad north-tr ending zones paralle l to the regiona l structu ral trend. Some deposit s are

***

AO?

*** -AG PS ---'

.-.--MICROGRAPHICS

.....

BUREAU----~-----------·--

broadLy stratabound, but no syngenetic strati form types are known. ALmost aLL of the deposits are LocaLised aLong fauLts, shEar zones, or tension cracks. The structuraL sites probabLy acted as channeLs for circuLating metaL-rich soLutions moving in response to deformationaL stresses and/or thermaL gradients associated with igneous intrusions, in particuLar doLerite intrusions. LithoLogicaL controL - mineraLisation is associated with particuLar LithoLogies but not restricted to stratigraphic units. particuLarLy favourabLe rock types are carbonaceous bLack shaLes (deposited in euxinic environments), caLc-silicate rocks, and metabasaLt. The more important reef goLd deposits in tne SoLdiers Cap Formation occur at, or c Lose to, a particuLar stratigraphicaL horizon where it is cut by cross-fauLts or intersecting fauLts. This hori zon is near the base of the middLe section of the SoLdiers Cap Formation, beLow the succession of metabasaLts (amphiboLites) and arenaceous metasediments. GENETIC MODELS: The shear- and fauLt-controLLed vein copper-goLd deposits are considered (0 J perkin in BLake & others, 1984) to have resuLted from the Leaching of copper from mafic igneous rocks into suLphur-bearing bLack sha Le, doLomite, caLc-si Licate rock, or arenite at some stage between earLy diagenesis and the end of regionaL metamorphism. BasaLtic voLcanics were probabLy the uLtimate source for most of the copper and other metaLs, aLthough doLeritic dykes, si Lls, and other intrusions may have aLso contri buted coppe r. FavourabLe zones for copper ore deposition are where reactive rocks such as carbonates are Located near permeabLe zones connected with nearby mafic rocks; the permeabLe zones may be fau Lts, breccia zones, or congLomerate bands. Most copper is thought to have been originally deposited durinQ Late diagenesis in a sabkha or rift-sheLf (shaLLowLacustrine) envHonment in an int,"acratonic tectonic setting. However, much of the copper was remobi Lised and concentrated during subsequent tec toni sm and metamorp hi sm. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: cLoncurry The cLoncurry GoLd and MineraL Fie Ld Lies in the Eastern FoLd BeLt of the Mount Isa InLier. The buLk of goLd mineraLisation was associated with epigenetic vein copper deposits; some reef and aLLuviaL goLd occurred in the CLoncurry area. REGIONAL SETTING: MOUNT ISA INLIER The Mount Isa InLier consists of a centraL north-trending structuraL ri dge of ea rLy prote ro zoi c basement metasediments, fe Ls i c vo Lc ani cs and intrusives - KaLkadoon-Leichhardt BeLt - overLain unconformabLy by thick cover sequences of marine sediments and bimodaL voLcanics - the Eastern and Western FoLd BeLts. The cover sequences were deposited during transgressive cycLes in a subsiding basin to the west of the centraL high, and on a continenta L she Lf/s Lope basin to the east. These rocks were formed on unstabLe crust in either a continentaL margin or intracratonic setting [see BLake (1987) for discussion and references], and in consequence were subjected to muLtipLe episodes of deformation, intrusion and metamorphism. The inLier was essentiaLLy stabiLised at the cLose of the Carpentarian. The inLier is characterised by north-trending fundamentaL Lineaments and fauLts, generaLLy conjugate sets of northeasterLy and northwesterLytrending fauLts, and compLex foLding. REGIONAL SETTING: EASTERN FOLD BELT The cover sequence of the Eastern FoLd BeLt comprises metamorphosed shaLLow to deep marine clastic and chemicaL sediments and mafic and feLsic voLcanics making up the SoLdiers Cap, MaLbon, Mary KathLeen and

...._ _...-

*** e07 ,>~~ ... .-._.......

~

. . AGPS--..

1fIII5IIIIII1l_1III=--

MICROGRAPHIeS BUREAU

IIIIIIIIIIII

Mount Albert Groups. The succession is intruded by dolerite, layered gabbro~ and syn- to late-tectonic granitoids (Wonga, Naraku and Williams Sathol,ths). The Soldiers cap and Mary Kathleen Groups are the main hosts to gold mineralisation. ASSOCIATED MINERALISATION Gold mineralisation is the Mount Isa Inlier waS concentrated in the northern part of the Cloncurry-Selwyn Zone [slake (1987)J of the Eastern Fold Belt (Cloncurry Gold and Mineral Field). Three-quarters of production was won as a by-product of copper mining; the remainder was derived roughly equally from reef gold and alluvial sources. GEOLOGICAL SETTING: CLONCURRY The principal copper-gold deposits were Hampden, Mount Elliott, Trekelano, Duchess, also Answer, Mount Mascotte, Mount McNamara. The copper-gold orebodies fall in the category of "shear and faultcontrolled vein-copper deposits" [Slake (1987)] which numerically make up the majority of the many copper deposits in the inlier. The veins are associated with carbonaceous and pyritic slates, calcsilic"te rock~ or metabasalt, and typically localised on faults, shear zones or tenslon cracks. Mount ELLiott, Hampden, and Answe," were in carbonaceous black s late of the Kuridala Formation; Duchess, Trekelano, and Mount Mascotte are in shear Zones in calc-si licate rocks of the corella Formation; and Mount McNamara is in Marimo Slate. The chief reef mining centres of the field were south and east of cloncurry at Gi lded ROse, pumpkin Gully, Mount Freda, comstock, Falcon, and Soldiers Cap. Alluvial gold was mined from ToP Camp and pumpkin GulLy. The reefs occur in fault or fracture planes, or in shear zones. Reefs occurred at the contact between quartzite and mafic volcanics (Victoria) and in fissure veins in slate and quartzite (Gertrude). production from the smaller copper-goLd and Qold veins has been derived from the oxidised zone, in which mineralisatlon was strong ly enriched by supe rgene processes. su lp hi de ore was mi ned at the la rgel" mi nes at Duchess, Trekelano, Hampden and Mount Elliott. Elsewhere in the inlier, isolated deposits occur in the Bower Sird and Doughboy Creek areas, and at May Downs, and Agate Oo~ns. Gold has also been obtained from alluvial deposits, mainlY near Cloncurry, and from the late Adelaidean Quamby Conglomerate, where epigenetic (hydrothermal?) gold Ol~curS with hematite in the conglomerate mat ri x. Some potentially economic gold deposits are contained in massive, banded and locally brecciated quartz-hematite bodies anomaLous ly rich in gold, and also copper, near Selwyn. The bodies are hosted by Mitakoodi Quartzite, Answer Slate, Stave ley Formation, and Kurida la Formation, and in screens of country rock within intrusions of metadolerite and Gin Creek Granite. starra (Deposit No. 16) is of this type. The origin of these bodies is uncertain - althouQh generally concordant with bedding, they are considered to be epigenetlc by Slake & others (1984). ORESODY: Gilded Rose The Gilded Rose group of auriferous reefs occurs in fissure veins associated with strike faults and east-southeasterly striking transverse faults cutting schist and quartzite of the Mount Norna Quartzite (SoLdiers Cap Group). [he host metasediments are close to a band of amphibolit e • practical y all production Was derived from the oxidised zone. ORESODY: Hampden orebodies occurred in a north-trending bedding-strike shear zone, the Hampden Fault, which is up to 60 m wide and cuts slate of the Kuridala Formation and amphibolite (metadolerite) on the eastern limb of an elongate south-pitching syncline. Slates in the shear zone are crushed against the more competent amphibolite. ORESOOY: Mount Ell i ott

...

*** C07

,~**

Il!liI]-AGPS - _..

ma---

MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - -....

Orebody occurred in a north-northwesterly trending shear zone in the Kuridala Formation in slate adjacent to amphibolite - a sill-Like mafic intrusive with minor dykes along the margins. The orebody consisted of three main ore shoots arranged en echeLon in section. The country rocks are hornfe Lsed slates. OREBOOY: Tre ke Lano OrebodY occurred in a northerLy-trendi ng( steep Ly west-dipping shear zone cutting hornbLende schist, amphibOlltic granofels, red and grey banded calc-siLicate rocks( and scapoLite-pyroxene g:-anofeLs of the CoreLla Formation, and apLltic granite of the Mount ErLe Igneous CompLex. The ore shoots were associated with subsidiary zones of shearing which traverse the main shear zone diagonally at 20 deg. REFERENCES: Blake D.H. 1984 GeoLogy of the Duchess-Urandangi region, ~tount Isa Inlier, Queens Land. Bureau Mineral Resources, Australia. BUlletin 219 Blake D.H. 1987 Geology of the Mount Isa Inlier and environs, Queensland and Northern Te rrito ry. Bureau MineraL Resources, Australia. BulLetin 225 Brooks J.H. , 1975 Sundry mineraLization in the Mount IsalCloncurry district. IN Knight C.L.(ed) - Economic geology of AustraLia and Papua New Guinea - l.~letals. AusH1M. Monograph Series 5 P402-403 Carter E.K. , Brooks J.H. , WaLker K.R. , 1961 The precambrian mineraL beLt of north-western QueensLand. Bureau MineraL Resources, AustraLia. BulLetin 51 Carter E.K. , Brooks J .H. , 1965 GeoLogy and mineralisation of north-western QUeens Land. IN MCAndrew J. (ed) - GeoLogy of AustraLian ore deposits. 8th CommonweaLth Mining & MetaLLurgical Congress, Australia & New ZeaLand, 1965, MeLbourne. AUS IMf1 1 P221-232 NYe P.B. , Rayner E.O. , 1940 The Cloncurry copper deposits, with specia L reference to the goLd-copper ratios of the ores. Aerial, GeologicaL & Geophysical Survey of Northern Australia. QLd Repor

35

WaLker K.R. , 1960 The geo Logy of the ouc hess-Tre ke lano area, north weste rn Queens land. Bureau of MineraL Resources, Australia. Record 601 41 0000000000000000000000000000000000000000

-AGPS--.....

pIIIII-- MICROGRAPHIeS BUREAU -----~---------------. DEPOS IT:

16

STARRA

DEPOSIT IDENTIFICATION:

---------------------SYNONYMS: se Lwyn ,

PRINCIPAL COMMODITIES: Au , A9 , Cu , MINES: Sta rra , ORE80DIES: Sta rra , GROUP: C loncurry Group COM~lENTS :

See Deposit No. 1S cloncurry for regional setting of Mount Isa Inlier, Ea:>tern Fold 8elt, and Cloncurry group. LOCATION: LATITUDE: 21 41 2S0K SHEET: SF54 6

LONGITUDE: 140 29 100K SHEET: 6954

ADMINISTRATIVE SU8DIVISION: MINING DISTICT: Cloncurry MINING FIELD: C loncurry LOCALITY: DEVELOPMENT HISTORY: DISCOVERY ~lETHOD Geochemistry Dri lling Geo logy Geop hys i cs

DISCOVERY YEAR 1984 1984 1984 1984 OPERA TlNG STATUS AT 198? MINE Starra Starra

STATUS Operati ng Operati ng

~lINING METHOD unde rg round open-cut

COMPANIES: ORE80DY: Sta rra COM~lENTS

PRESENT OPERATORS:

1lIi:IIIlIIII

***

EO?

***

ffiJi]j-AGPS - _..

.---M ICR OGR APH ICS BURE AU - . . . , - - -----------ELders Resourc es Ltd. PRESENT OWNERS: Arimco N L. Cyp rus Mi ne ra Ls AUs t ra Li a Co. ELders ReSourc es Ltd.

EQUITY 737.50 37.50 25.00

- -....

COMMENTS

PRODUCTION: MAIN PRODUCTION PERIODS: 1988- , RESOURCES: DATE

OREC'OOOt)

GRADEC9/t)

GOLDC kg)

CLASS IfIC AnON

Dec 1987

4,500

4.5

20,250

Economic Demons trated RecoverabL~

PRE-~lIN E

olc

RESOURCE SIZE: M

GEOLOGY: PROV INCE: BLOCk: PROVINCE: Mount !sa InLier SUB-PROVINCE: Eastern FoLd BeLt HOST ROCKS: kuridaL a Formatio n ~lica schist, metagreY 14acke, bLack sLate, ~,yLLite, meta-ar kose, quartzi te; minor banded calc-si licates , banded iron formatio n, mafic metavoL canics. Conform ably to unconfor mabLy overlai n by host StaveLe y Formati on in deposit area. StaveLe y Formatio n VariabL y feLdspa thic, fe r rug i nous micaceo us and caLcareo us phylLite /shaLe/m udstone and interbed ded e and si Ltstone . Copper-g oLd mineral isation occurs in foursandston zones in deforme d, conform abLe, steep Ly dipping banded quartz- magnet ite-hem atite b"dies and ferrugin ous schists at the base of the Stavele y Fm. Mount Dore Grani te Intrudes host sequenc e in deposit area. Gin Creek Granite Intrudes host sequenc e in deposit area. AGE: protero zoic MiddLe / STRUCTURAL FEATURES MAJOR: Fold Axis, FoLdin g,

....

.....~

*** F07

,~**

...._ - -

IUi] J-AG PS - - - '

p:m=--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - . . . STRUCTURAl/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY SIGNIfICANT: pLutonism(Granite) , AGE OF INTRUSION: proterozoic MiddLe METAMORPHISM: RegionaL metamorphic grade is amphiboLite facies. ALTERATION: The country rocks are both metamorphosed and aLtered, effects not cLearLy distinguishabLe. Adjacent to mineralised ironstone the wall rocks, especially the footwaLL, are commonLy brecciated, highLy chLoritic and granuLar textured with abundant scapoLite and amphiboLes. This zone is generaLLy absent adjacent to unmineraLised ironstone and may represent aLteration associated with mineraLisation. Throughout the footwaLL schists, magnetite-chaLcopyrite-chlorite veining is common. Carbonate, quartz-feldspar, epidote and amphibole veining is mostly restricted to the calcareous and feLdspathic hangingwall caLc-si licates. DEPOSIT CHARACTERISTICS: TYPES: stratiform gold-copper-bearing quartz-hematite (banded iron formation) in metasediments. ALLuvial. STYLE: conformable, stratabound , AGE OF MINERALISATION: Proterozoic MiddLe DH1ENSIONS: OREBODY: Starra STRIKE LENGTH TRUE WIDTH

MIN m m

AVE 200.0

MAX 3500.0 30.0

NATURE OF MINERALISATIOI~: Banded/Laminated, Disseminated, NINERALOGY: OREBODY: Starra suLphide zone: chalcopyrite (5-107,), subordinate pyrite, minor bornite. Gangue: quartz-magnetite-hematite +-carbonate, minor scneeLite. Gola is fine-grained, typicaLLy 5-10 microns and occurs in chalcopYrite and quartz. AU~ cu, and W abundances are cLose ly corre lated. Sn, Co, and Mo are weaklY anomaLous. GENETIC CONTROLS: Deposit is strongLy structuraLLy controLLed. Restriction of mineraLisation to the highLy strained Hinge Zone and Western Ironstones and in particuLar to discrete highLy deformed foLds attributed to D2 suggests structurally controLLed LocaLisation during D2.

,~**

GO 7

M,,~

lIlwiam&I----------~------------~-AGPS

-_l1li

1Flll'lIII--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - 1 I : l I I I I I I GENETIC MODELS: The ironstones may have contained anomalous syngenetic gold and copper, which was remobi lised and concentrateCl curing deformation. Alternatively, igneous or metamorphically derived metal-bearing fluids may have been channelled along structurally favourable zones. GEOLOGICAL SETTING OF MINERALISATION: ORE;300Y: Sta rra Starra occurs in deformed and metamorphosed i ronstones (?banded-ironformation) and iron-oxide bearing schists at the base of the mid Proterozoic Staveley Formation in the Eastern Fold Belt of the Mount Isa Inlier. The Staveley Formation comprises variably feLdspathic, micaceous, and calc~reous iron-oxide bearing schists anCl caLc-silicates. In the deposit region the Staveley Formation conformably to unconformably overlies quar';zite and schists of the Kuridala Formation. TWO Ilain periods of deformation have produced tight north-south foLds with generally steep easterly dipping axial p lanes. Numerous pre- or syn-cectonic Cloleritic sills cccur throughout the area. The posttectonic Mount Dore !ilranite outcrops 500 m east of the Eastern IrO'lstones. The follated pre-or syn-tectonic Gin Creek granite outcrops 50':1 m west of the Western Ironstones. The mineralised ironstones are two apparently stratigraphically I:onformable bodies, termed the Eastern and Western Ironstones, which outcrop oVer 15 km roughly one km apart. The ironstones are llnked at one point by a fold closure termed the Hinge Zone. ~lineralisation occurs in four discrete zones which are spatially associated with thickened, brecciated, steepLy dipping fold noses (inferred 02) in the Hinge Zone and along the Western Ironstones. The ironstone horizons generally consist of more than one discontinuous iron-rich layer up to 30 m thick. Mineralised ironstone is generally medium to coarse-gra; ned, brecc iated and i ndi sti nctly layered. unmineralised ironstone is finer grained and more distinctly layered. Footwall to the ore zones = highly strained chloritic and feldspathic magnetite and pyrite bearing schists. Hanging wall less strained calcareous metasediments.

=

REFERENCES: B la ke O. H. 1 984 Geology of the ouchess-Urandangi region, ~lOunt !Sa Inlier, Queens land. Bureau Mineral Resources, Australia. Bulletin 219 Blake o.H. 1987 Geology of the Mount Isa Inlier and environs, Queensland and Northern Te r ri to ry. Bureau Mineral Resources, Australia. Bulletin 225 Collins S. ,1987 The geophysics of the Starra gold-copper deposits. IN Australian Soceity of Exploration GeolJhysicists. 5th Geophysical Conference & Exhibition, perth, February 1987. Extended abstracts. Exp loration Geophysics 18(1/2) P20-21 Laing W.P.

, Rubenach

~l.J.

, Switzer C .K.

, 1988

-_..

1!simIa--..-&II------------------~Ji]-AGPS

1IflIIDI1IlIIZIII-

MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - -.. The Starra 90Ld-copper deposit - syndeformationaL metamorphic mineraLisatlon Localised in a foLded earLy regionaL zone of decoLLement. IN Achievements in AustraLian geoscience. 9th AustraLian GeoLogicaL Convention, Brisbane, February 1988. GeoLogicaL Society of AustraLia 21 p229 Morrison I. , 1986 The Starra goLd(-copper) project, northwest QueensLand. IN GoLd exp Loration and deveLopment, north QueensLand. AusU1M conference, Chal"ters Towers, August 1986. Extended abstr~cts. AusIMM. North QueensLand Branch 1v P87-93 0000000000000000000000000000000000000000

1bmm---------------------~-AGPS--1lIIliI1

1JlllIIII--MICROGRAPHICS BUREAU

DEPOSIT:

17

EiISII

CAPE RIVER

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: AU , MINES: Cape River, OREBODIES: Cape River, LoLworth , Lower Cape, Mount C Learview , Mount Emu, RemarkabLe, Mount Stewart , Upper Cape-Gorge Creek,

Mount

GROUP: permo-Carboniferous Igneous Group COMMENTS: IncLudes setting of a group of smaLL deposits distributed over Cape River region 75km x 50km. See Deposit No. 19 Charters Towers for regionaL setting of Lo L~lorth-Ravenswood BLoc k.

= area

LOCATION: LONGITUDE: 145 23 100K SHEET: 7957

LATITUDE: 20 27 250K SHEET: SF55 ADNINISTRATIVE SUBDIV ISI,.!N:

NINING DISTICT: Charters Towers mNING FIELD: Liontown LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD P rospec t i ng

DISCOVERY YEAR 1867 OPERA rING STATUS AT 1 987 MINE Cape River Cape River Cape River

STATUS HistoricaL OlJe rati ng Hi stori ca L

MINING flETHOD unde r!;jround ALLuv, a L ALLuviaL

COMPANIES: OREBODY: Cape River COMNENTS

PRESENT OPERATORS: GoLden Shamrock ~lines Ltd.

1l=as:I

~'r**

J 07

~'n':"r -:l_~-AGPS

- _..

m---MICROGRAPHICS

BUREAU-------------------1IlI!IIII!.I EQUITY

PRESENT OWNERS: GoLden Shamrock Mines Ltd.

100.00

r.

CO~l~IENTS

PRODUCTION: CU~lULATIVE pRODUCTION (TO DEC.1986):

ORECt):

GOLDCkg)

1,400

RECOVERED GRADECg/t)

0.00

.

CO~lMENTS

Ore tonnages and recovered grade not app LicabLe to aLLuviaL deposits. Zero figures resuLt from program caLcuLations.

MAIN PRODUCTION PERIODS: 1867-1938 , RESOURCES:

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman FoLd BeLt PROVINCE: Thomson orogen SUB-PROV INCE: Lo Lworth-Ravenswood BLoc k HOST ROCKS: Campaspe Beds CLayey, gritty sanc;lstone; congLomerate, si Ltstone. Host to the Cape RlVer CLower Cape) deep Lead, the Largest deposit of the region. Cape River Beds phyLLite, quartzite, amphiboLite, garnet-biotite greiss. Host to minor mineraLisation in numerous smaLL primary and near granite contacts, principaLLy at ~lount RemarkabLe, C Lea rv i ew.

secondary deposits Upper cape, Mount

Mundic Igneous compLex Porphyritic Leucocratic microgranite; voLcanic breccia, minor intrusives from doLerite to microgranite. Host to primary mineraLisation at ~lount Stewart.

ranging

Ravenswood Granodi ori te Comp Lex FoLiated biotite granite, adameLLite, granodiorite, minor gneiss, migmatite. Host to minor vein mineraLisation in schistose granite in Lower Cape area; possibLe source of Cape River deep Lead. Lo Lworth Igneous Comp Lex Biotite granite, adameLLite( garnet-muscovite pegmatite, apLite. Host to primary mineraLisat10n in veins and greisens, e.g. LoLworth, and

*** KO 7

source

,~*,',

-AGPS--iIIlIIIIIi

e---MICROGRAPHICS

BUREAU-------------------

lIIIIIIIllD

of minor aLLuviaL mineraLisation AGE: paLaeozoic ordovician AGE: paLaeozoic cambrian STRUCTURAL FEATURES SIGNIFICANT: Fracturing , STRUCTURALlSTRA nGRAP HIC INTERSEC nONS IGNEOUS PROXIMITY MAJOR: pLutonism(Granite) , AGE OF INTRUS ION: pa Laeo zoi c La te Pe rmi an AGE OF INTRUSION: paLaeozoic EarLy Devonian AGE OF INTRUS ION: pa Laeozoi c Late Si Luri an METAMORPHIS~l:

The Cape River Beds were regiona LLy metamorphosed to the upper greenschist and Lower amphiboLite facies prior to intrusion. Most of the Cape River Beds probabLy faLLs within the quartz-aLbite-epidotebiotite subfacies; the aLmandine-amphiboLite facies is LocaLLy deveLoped in the northeast.

ALTERA nON: Mineralisation is associated with greisenisation of the host granite. DEPOSIT CHARACTERISTICS: TYPES: Auri fe rous qua rtz vei ns in metasediments adj acent to g rani toi d. ALLuviaL. STYLE: conformabLe , stratabound , MORPHOLOGY: FLat-Lying, AGE OF MINERALISATION: cainozoic pLiocene Tertiary AGE OF MINERALISATION: paLaeozoic Late permian AGE OF MINERALISATION: pa Laeozo; c Ea r Ly Devon; an AGE OF MINERALISATION: pa Laeo zo; c Late si Lurian DnIENSIONS: OREBODY: La Lworth VERTICAL DEPTH OREBODY: Lower Cape

m )

TRUE WIDTH DEPTH OF COVER OREBODY: ~Iount Emu

cm ) m )

MIN 30.0

AVE

mN 30.0

AVE

30.0

MAX 59.0 ~'AX

50.0

-AGPS _ _IHEI

.---MiCROGRAPHICS STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: ~lOunt Stewart

m ) cm ) m )

STRIKE LENGTH TRUE WIDTH ( VERTICAL DEPTH OREBODY: Upper Cape-Gorge

m ) cm ) m ) Cree k

VERTICAL DEPTH

m )

MIN

MIN

MIN

BUREAU-------------------... AVE

MAX 400.0 150.0 30.0

AVE

30.0

MAX 300.0 100.0 24.0

AVE

MAX 12.0

NATURE OF MINERALISATION: Free Milling, PRIMARY ORE: Vein (Reef) , SECONDARY ORE: Deep Lead , MINERALOGY: OREBODY: Lo lworth Greisenised granite: gold, pyrite, arsenopyrite, chalcopyrite, sphalerite; small amounts of wolframite, scheelite, molybdenite, bismuth, tourmaline; rare torbernite, bournoni te. OREBODY: Lower Cape Qua rt z-go ld. OREBODY: Mount Emu Greisen: gold, gaLena, pyrite, arsenopyrite, sphaLerite. GENETIC CONTROLS: primary structuraL controL was apparentLy the north- to northeasttrendi ng fracture system. GENERAL MODELS The variety of style of primary mineralisation suggests that more than one period of mineraLisation is represented. The most likely source of the gold at Mount Emu is the Dumbano Granite and at Mount Clearview the LoLworth Igneous CompLex. Other deposits hosted by the Lolworth Igneous Complex or in Cape River Beds near a granite contact, e.Q. Upper CapeGorge Creek and Mount Remarkable, are more closeLy assoclated with younger cross-cutting feLsic dykes than with the LIC. Mineralisation is here probably not derived from the LIC but is more likely reLated to a younger high leveL intrusive phase (with which the feLsic dykes are affiL i ated). GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Cape River REGIONAL SETTING The southwestern margin of the LoLworth-Ravenswood Block is occupied by a northwest-trending belt 80 km long x 16 km wide of Cambrian-Ordol/ician metamorphic rocks,. the Cape River Beds. The nietamorphics are intruded in the eastern end of the be Lt by granodiorite of the syntectonic Ravenswood Granodiorite CompLex, and both are intruded on the northeast by a large post-tectonic batholith, the Lolworth Igneous CompLex. The coeval Dumbano Granite intrudes the Cape River Beds in the northwest. The PaLaeozoic rocks are overLain on the southwest by Permian-Triassic continentaL sedimentary sequences of the Gali lee Basin. The Cape River 8eds comprise coarse muscovite schist, hornblende schist, garnet-mica schist and lit-par-lit Qneiss, mica schist, calcsilicate rocks, amphibolite, quartzlte, minor 9ranofeLs, marble, hornfels and metagreywacke. strike ana foliatlon are west-nortnwest and

...

*** MO?

l~**

----------------------(1i~-AGPS--

..

~--MICROGRAPHICS

BUREAU-------------------...

dip is to the south-southwest at 20-40 deg. The Ravenswood Granodiorite CompLex is represented mainLy by foLiated biotite granite in the southeast, and in the northwest by more strong Ly foLiated adameLLite and granodiorite with Local deveLopment of orthogneiss and migmatite. The LoLworth Igneous CompLex comprises massive biotite granodiorite and adameLlite pLus banded, pegmatitic and apLitic garnet-muscovite granite f and adame LLite. Much of the Ravenswood Granodiorite compLex and LoLworth Igneous CompLex terrain is overlain by the Campaspe Beds, a bLanket of Tertiary (P Li ocene) pi edmont sediments up to 15 m thi c k de rived mai n ly from the granitic basement. The unit comprises pebbly, cLayey, gritty sandstone, cong Lomerate, and minor si Ltstone and is host to the Largest deposit of the region, the Cape River deep Lead. The major structuraL feature is the northwesterly trend of the fo Liation in the Cape River Beds and most of the Ravenswooa Granodiorite Complex. The main trend of fauLting is across the foLiation from east-northeast to northeast; the fauLts probabLy originated during the period of northeast-southwest compression when the Cape River Beds were foLded. ASSOCIATED MINERALISATION The Cape River Beds are host to minor goLd mineraLisation in numerous smaLL vein and aLLuvial deposits (e.!3. Mount RemarkabLe, Upper Cape, Mount Clearview). other mineraLisatl0n is hosted by or aerived from the various granitic rocks (e.g. Lower Cape, Mount stewart, LoLworth, Mount Emu); more than one period of mineraLisation is represented by the different types of primary deposits present. The Largest deposit in the southwestern portion of the Lolworth-Ravenswood BLock was the cape River deep Lead which consisted of auriferous congLomerate at the base of the Tertiary Campaspe Beds. OREBODY: LoLworth MineraLisation occurred in biotite adameLLite of the Lolworth Igneous CompLex near the margin of the exposed part of the LoLworth-Ravenswood BLock. The adameLlite is cut by dykes affiliated with the Mundic Igneous comp le x 15 km to the southeas t. The orebodies consisted of i) smaLL veins or vein stockworks with greisenised aureoLes, ii) pipes of greisenised granite, iii) pegmatitic quartz veins in fissures in the granite. OREBODY: Lower Cape The largest degosit was the Cape River deep lead. MineraLisation consisted of 30-50 cm of auri ferous cong Lomerate - the basaL congLomerate of the Campaspe Beds - resting on schist and overlain by virtually barren finer sediment. The northern end of the lead was narrow but shallow and rich. southwards it became progressiveLy deeper, wider and poorer. About 4 km south of the northern end a Large apLite dyke forms a high bar in the bedrock south of which the grade feLL off abruptLy. GoLd was also won from other deep Leads, quartz veins and Recent aLLuvium. The Lode deposits were reportedLy northeast-trending in granitoid schist of the Ravenswood Granodiorite complex. OREBODY: Mount cLearview primary mineraLisation occurred in four lodes in fine-grained gneiss and schist of the Cape River Beds near a contact with Ravenswood Granodiorite compLex. The metamorphics trend northeast, but the Lodes occupy meridionaL fissures. The schists are cut by granitic dykes aLso stri ki ng northeast. OREBODY: Mount Emu MineraLisation occurred in Dumbano Granite near a contact with Cape River Beds. The granite is muscovite-bearing in the deposit are'!. The orebodies were in quartz veins or zones of greisen plus quartz Lenses in fissures in the granite. OREBODY: Mount RemarkabLe Both a Lluvial and Lode deposits were worked. The primary goLd

....

-...

*** NO?

**,~

~

~-AGPS--IIIIIIII

...---MICROGRAPHIeS BUREAU---....----------~--...... mineraLisation occurred in quartz veins closeLy associated with fe Lsic pc.rphyry dykes into which they merge in pLaces. The veins occupied meridionaL fissures in quartzite and mica schist of the Cape River Beds. Some mineraLisation may be reLated to ?Late Permian voLcanics. OREBODY: Mount Stewart North- to northeasterLy.~trending Lodes are associated with porphyritic Leucocratic micro!iranite of the subvoLcanic Mundic Igneous complex. The microgranite , s an epi zona l stock emp Laced as the last phase of the comp Lex. OREBODY: upper Cape-Gorge Creek PrimarY mineraLisation occured in narrow northwest-trendin!i rich quartz veins near the contact between metasediments of the Cape Rlver Beds and bioti te-ri ch gnei ssic adame II ite of the Ravenswood Granodiori te Comp Lex. Most of the Lodes were in the Cape River Beds. Some were reported to originate from, or occur within, felsic porphyry dykes or silLs. Alluvial goLd occurred in smaLL rich Leads in buried paLaeochanneLs over hornblende schist bedrock. Gold vaLues drop off at the bedrock contact. The sources for the aLluvial deposits are the adj acent vein systems and primarY deposits up to 30 km upstream along the Cape River channeL. REFERENCES: Brooks J.H. , 1960 precambrian - The charters Towers, Cape River and Woolgar goldfields. GeoLogical Society of AustraLia. Journal 7 P75-76 Daintree R. , 1868 Report on Cape River diggings. QueensLand. parLiamentary paper 1v Marks E.O. , 1910 cape River goLdfieLd. Queensland Government Mining JournaL 11 P340-341 paine A.G.I.. , Harding R.R. , 1965 The geology of the north-eastern part of the Hughenden 1 :250 000 Sheet a rea, No rth Queens Land. Bureau of MineraL Resources, AustraLia. Record 65/ 93 paine A.G.L. , Harding R.R. , C larke D.E. , 1971 GeoLogy of the northeastern part of the Hughenden 1 :250 000 Sheet area, QIJee ns la nd. Bureau MineraL Resources, AustraLia. Report 126 Rands W.H. , 1891 Cape River go Ldfi e Ld. GeoLogical Survey of Queensland. 73

publication

0000000000000000000000000000000000000000

*** A08 ,\**

-AGPS--'"

~--MICROGRAPHICS BUREAU--------~----------.. DEPOSIT:

18

FAR FANNING

DEPOS IT IDENTIFICATION: PRINC IPAL COMMODITIES: Au , Ag , MINES: Far Fanning, Mount Success, ORE80DIES: Bank Of England, Far Fanning, Golden Valley , Great Caesar 0' shea , Lancashi re Lass, Lancashi re Lass No. 1 West, Mount Mount Macalight , Mount Success, Spotted Calf,

, Kitty Hogan ,

GROUP: Permo-Carboniferous Igneous Group COMMENTS: Includes regional setting of Devono-Carboniferous 8asins. See DelJos it No. 23 Pajingo for regional setting of 8urdekin Basin; Deposit No. 12 Kidston for regional setting of permo-Carboniferous igneous grOUp. LOCATION: LATITUDE: 19 40 250K SHEET: SE55 14

LONGITUDE: 146 22 100K SHEET: 8158

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Charters Towers ~lINING FIELD: charters Towers LOCALITY: DEVELOPMENT HISTORY: DISCOVER~

METHOD prospect1n9 pro spec t, ng

DISCOVERY YEAR 1866 1890 OPERATING STATUS AT 1987 MINE Far Fanning Mount Success Far Fanning

STATUS Historica l Hi storica l Operati ng

MINING METHOD Unde rg round Underground OPen-Cut

COMPANIES: ORE80DY: Far Fanning PRESENT OPERATORS:

. . ._ _..

COMMENTS

*** B08

*,~* .... _ _·..

~

. . AGPS--..

r.-_-----..

~

pR--MICROGRAPHICS BUREAU The Northern Queens land Company Ltd. PRESENT OWNERS: BHP Gold Ltd. The Northern Queens land Company Ltd.

EQUITY 51.00 49.00

r.

COMMENTS

EQUITY 100.00

r.

COMMENTS Formerly Ltd.

OREBODY: Mount Success PRESENT OWNERS: Aus tra lmi n Ho ldi ng s Ltd.

A.O.G.

Mi r,e ra ls

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORECt): 68,000

GOLDCkg) 177

RECOVERED GRADECg/t) 2.60

COMMENTS

MAIN PRODUCTION PERIODS: 1895-1908 , 1986- , RESOURCES: DATE

OREC'OOOt)

GRADEC9 It)

GOLDCkg)

CLASS IF ICATION

Dec 1987 Dec 1987

500 162

2.3

1,150 697

Economic Demonstrated In-Situ Economic Demonstrated In-situ

4.3

o/c

u/g

oxi di sed su lphi de

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: TasmC'n Fold Belt PROVINCE: Devono-Carboniferous Basins SUB-PROVINCE: Burdekin Basin HOST ROCKS: Dotswood Formation Feldspathic sandstone, arkose, quartzite, conglomerate, red shale, siltstone, tuff. Some mineralisation comprises conformable gold-quartz veins interbedded with sediments. Far F~nning Group Shale, siltstone, arenite, and limestone. Host to rhyolite intrusive-associated mineralisation at Mount Success. !nt rus ive rhyo lite. some mineralisation comprises gold-quartz stockworks and breccias associated with felsic dykes wh'ich intrude Dotswood Formation.

...

***

c08 *H,

~_-=--lji]].-AGPS--IIIIII

1IPIII'IlI--MICROGRAPHICS BUREAU---...-

.....- - - - - - - - - - - - -......

AGE: Pa laeo zoi c Late Devoni an STRUCTURAL FEATURES MAJOR: Fold Axis, SIGNIFICANT: Faulting, Folding, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS SIGNIFICANT: Intrusive Contact, IGNEOUS PROXIMITY MAJOR: Plutonism(Granite) , Sub-Volcanism(Felsic porphyry) , AGE OF INTRUSION: palaeozoic Early permian AGE OF INTRUSION: palaeozoic Late carboniferous ALTERA TION: OREBODY: Far Fanning Mineralisation is associated with strong sericitic alteration and si licification. The host sediments are weakly altered around the ore le nses. OREBODY: Mount success The host sediments have been thermally metamorphosed to a variety of skarns mostly by intrusion of the mineralised rhyolite, possibly also by the andesite dykes. DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in metasediments adjacent to felsic/intermediate porphyry intrusive. STYLE: conformable, Discordant, stratabound , MORPHOLOGY: Lenticular, pipe-Li ke , AGE OF MINERALISATION: palaeozoic Early permian AGE OF MINERALISATION: palaeozoic Late Carboni ferous DIMENS IONS: OREBODY: Far Fanning STRIKE LENGTH TRUE WIDTH OREBODY: Great Caesar

m m

TRUE WIDTH cm) VERTICAL DEPTH (m) OREBODY: Lancashi re Lass STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Mount Success

m)

cm )

m)

MIN

AVE

MAX 1700.0

2u.O

2.0 MIN 25.0

AVE

MAX 100.0 30.0

MIN

AVE

MAX 60.0 175.0 30.0

10.0

*** 008

,~**

-AGPS---·

....--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - -••--,.. STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH

( m ( m ( m

AVE

MIN

MAX

650.0 10.0

40.0

NATURE OF MINERALISATION: Disseminated, Free Mi Lling , PRIMARY ORE: 8reccia , pipe , Stockwork , Vein (Reef) , MINERAl.OGY: ORE80DY: Far Fanning Oxide ore: goLd is set in vuggy, trans Lucent to mi Lky coloured quartzand Fe-rich veins and breccias. SuLphide ore: goLd is associated with pyrite, minor arsellopyrite, gaLena, chaLcopyrite. GoLd grainsize is commonLy Less tllan 200 microns. OREBODY: Mount Success sulphide zone: pyrite, marcasite, sphaLerite, gaLena, cha'Lcopyrite, enarglte. Gangue: quartz, caLcite. GENETIC CONTROLS: controls are primary structuraL. On a regionaL scale the depusit is located on a major east-west 'fauLt zone, near its intersection ~~ith an anticlinal foLd axis. On a LocaL scaLe, mineraLisation occurs aL!)ng pLanes of weakness between sedimentary oeds, and in tension frac'tures and breccia zones. The structuraL sites were ~enerated by drag folding associated with movement along the east-west Llneament. GENETIC MODELS: The fracture-controlled vein styLe of mineraLisation supported by the open space textures in the veins, and the Limited extent of aLteration, sugQests the goLd was deposited at high LeveLs in the earth's crust by a flUld-poor mineralising system. The temperature of the mineraLising fLuid is unknown, but the styLe suggests an epithermaL origin: PermoCarboniferous granitoid magma, the source of the Mount Kitty 0' Shea intrusion, was aLso emp'Laced at depth beneath Far FanninQ, with associated doming, foLding and deformation of the overLYlng sediments. During the waning stages of intrusion, hydrothermaL fluids circuLating aLong permeabLe zones deposited goLd in bedding pLanes, the most favoured site for ore deposition as they were readiLy opened during Late staQe foLding; in fractUre sets; and in breccia zones at sites of ll1aXlmUm deformation. The fe Lsic dykes may be the source of the mineraLising fluid, aLthough intermediate dykes reLated to the Mount Kitty o'shea intrusive centre are aLso a possibLe source. Wyatt & others (1970) raised the possibi Lity that the mineralisation maY be much younger - Permain or younger - as the rhyoLite dykes are not reLated to the andesite dykes at Mount Kitty 0' shea, and have not been defi nite ly Linked to the Permo-Carboniferous pLutonic activity. GEOLOGICAL SETTING OF MINERALISATION: ORE80DY: Far Fanning Gold-Cluartz veins, stockworks and breccias of possibly Carboniferous or younger age are associated with feLsic dykes cutting Devonian sediments of the 8urdekin Basin. REGIONAL SETTING: 8URDEKIN 8ASIN The 8urdekin Basin developed on the northern border of the LolworthRavenswood Bloc k and received sedimentation from the Mi dd Le Devoni an through to the EarLy Carboni ferous. Ranging between a mi ldLy unstable shelf and a yoked intracratonic basin it presented an alternation of

~

...

_~

***

EO 8 '~*i(

-~-AGPSI---"

...---MICROGRAPHICS

BUREAU-----------------'-...

marine and continental conditions. The host sequence at Far Fanning, the Dotswood Formation~ is of markedly continentaL redbed type. The formation consists of an alternating succession 2400 m thick of feLdspathic sandstone, arkose~ quartzite, congLomerate and red shaLe with greY-9reen and purple siltstone and tuff, reRresenting a fluctuating contlnental/shaLLow marine environment of deposition. The sedimentary sequence was foLded into broad, open basin/dome structures controLLed by the underLying basement surface and intruded by stocks and pLutons of the Lake Carboniferous-EarLy permian igneous province. GEOLOGICAL SETTING: FAR FANNING Far F'lI1ning Lies near the intersection of the axis of a broad re!;!ionaL northwest-trending and pLunging anticline with a Lineament trendlng east-West between two permo-Carboniferous plutons. The permoCarboniferous rocks inc Lude granitoids rar.ging in composition from granite to adameLLite, granodiorite, diorite and gabbro, and are postuLated to occur at depth aLong the east-west Lineament beneath Far Fanning. one of the pLutons is the Mount Kitty o'shea intrusive centre which Lies 4 km west of Far Fanning and consists of a granodiorite stock and a set of radiaL porphyri tic andesite dykes. At Far Fannin!;! the ootswood Formation is cut by rhyoLite dykes of RossibLe Carbonderous feLsic voLcanic affinity, but which may be permian or younger. MineraLisation takes the form of i) tabular quartz vein/stringer stockworks in fracture sets in the feLsite dykes and ii) individual quartz veins more or less conformabLe with bedding. Current operations haVe aLso indentified metric size cLast supported breccia pod mineraLisation. Historical operations consisted of severaL mines on 3 main Lines of lode. current oRerations are based on a series of 8 broad ore Lenses which both paraLLeL and cross-cut bedding. The Lenses lie in a structuraLLy disrupted zone up to several hundred metres wide in which the sequence trends 14est to northwest. The eastern end of the deRosit lies on the axis of an open anticline; moving westwards the deposit zone shifts to the southern anticLinaL Limo, and Lies across a south-diPRing monocLine. Dip of the ore Lenses is normaL to the direction of maximum dip of strata (= direction of maximum fold steepening). The strongest mineraLisation (= highest grades, thickest veins and breccias) occurs in the conformabLe ore lenses. OREBODY: Lancashi re Lass Ore was associated with a near verticaL, easterly-striking dyke. OREBODY: Mount success MOunt Success occurs at the contact between granite of the Ravenswood Granodiorite compLex and overlying sediments of the MiddLe oevonian Fanning River Group. The Fanning River GrouR is the basaL sequence of the Burdekin Basin, and consists of sha Le, si Ltstone, arenite, and Limestone. The contact zone is cut by Carboni ferous rhyoLitic and dacitic intrusion breccia pipes and by andesite dykes reLated to the Kitty O'shea intrusive centre. ~lineraLisation is associated with the rhyoLite intrusion. ore zones occur as pipe-Like shoots distributed in an arcuate zone concave to the west a Long the grani te/sed;ment contact. REFERENCES: Cameron W.E. , 1931 The Mount success mine, Ravenswood Junction. Queens Land Government ~li n; ng Journa l

32 P318-319

~

1IIIIIIIIl--MICROGRAPHICS

BUREAU----·-=---------------.

ELLiott M. , Houtgraaf M. , 1986 The geoLogy and deveLopment of the Far Fanning goLd deposit. IN GoLd expLoration and deveLopment, north QueensLand. AusIM~l Conference, Charters Towers, August 1986. Extended abstracts. AUsIMM 1v P21-29 Lev i ng s to n K. R. , 1 971 MineraL deposits and mines of the Townsvi LLe 1 :250000 sheet area, North QUeens Land. GeoLogicaL Survey of Queens Land. Report 61 Rands W.H. , 1898 On the goLd mines at the Fanning and Mount Success. GeoLogicaL Survey of QueensLand. BuLLetin

8 WYatt D.H. ,paine A.G.L. ,cLarke D.E. , Harding R.R. , 1970 GeoLogy of tne TownsvilLe 1:~50 000 sheet area, QueensLand. BUreau MineraL Resources, AustraLia. Report 127 0000000000000000000000000000000000000000

***

G08

*** -AGPS-""'"

pIIIIII--MICROGRAPHICS BUREAU

DEPOSIT:

19

-------mIIiIIIrIIfl

CHARTERS TOWERS

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: AU , Ag , pb , MINES: Band Of Hope, BLack Jack, Bonnie Dundee, BrilLiant, BrilLiant And st. George , BrilLiant BLock, BrilLiant CentraL , BrilLiant Extended , Charters Towers, CLarks Gold Mines Dan O'conneLL Day Dawn BLock And wyndham, Eastward Ho, GeneraL Wyndham cLaims, Highway, KeLLys Queen Block, MilLs Day Dawn united, New Bri LLiant FreehoLds 6 New Queen, New Queen CentraL North AustraLian, Rainbow CLaims, Rain ow Lease, st. patrick, stoc'hoLm , sunburst, Victoria, Victoria And CaLedonia BLock OREBODIES: Black Jack , Bri LLiant , Charters Towers , cLarks Moonstone , coLumbia-Mystery, CumberLand , Day Dawn, GoLden ALexandra (Washington) , Highway, Identity, ImperiaL, John BuLL, Just-In-Time , Lady Maria , Moonstone, Moonstone (Cross) , North AustraLian , OLd Queen Cross , Queen, Rainbow-Wyndham , Ruby, st. George, st. patrick, stockhoLm, stockhoLm (Comstock) , StockhoLm (Cross) Swedenborg Victory, weLLington-Lord NeLson, GROUP: Charters Towers Group COMMENTS: Inc Ludes regiona L setting of LoLworth-Ravenswood B Lock and of Charters Towers group. Record i nc Lude the I inner' charters Towers deposits = NE-trending zone Skm x 1.2km across the town + a smaller paraLLeL zone 1.6km to the south. LOCATION: LA TITUDE: 20 4 250K SHEET: SFSS 2

LONGITUDE: 146 16 100K SHEET: 8157

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Charters Towers ~lINING FIELD: charters Towers LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng

DISCOV ERY YEAR 1871 OPERATING STATUS AT 1987 mNE

BLack Jack

....

STATUS HistoricaL

MINING METHOD Unde rg round

[iij-AGPS--..

1fIIIIIIII--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -1III8Ift Historical Historical Hi s tor; ca l Histor;cal

Bri lliant Band Of Hope Brilliant Block Bri lliant Centra l Bri II i ant Extended Bri lliant And st. George Bonni e Dundee Ke llys Queen Block New Queen Centra l V; ctori a Victoria And Ca le doni a Bloc k Cha rte rs Towe rs Clarks Gold Mi nes Day Dawn Bloc k And Wyndham Mi lls Day Dawn uni ted New Bri lliant Freeho Lds Clarks Gold Mi nes North Austral;an Band Of Hope Bonni e Dundee Rai nbow claims Ra i nbow Lease Gene ra l 14yndham Claims Eastward Ho Dan 0' Conne II st. patrick Stoc kho lm Band Of Hope Br; lliant Centra l Bonni e Dundee New Queen sunburst Charters Towers Hi ghway Black Jack Charters Towers

Ope rat i ng

Unde rg round Unde rg round Unde rg round Unde rg round

Historical

Unde rg round

Historical

Unde rg round

Histol";cal Historical

Underground Unde rg rOIJnd

Historical

Unde rg round

Historical Histor;cal

Unde rg round Unde rg round

Hi s tori cal Hi s tor; ca l

Unde rg round Unde rg round

Hi s tori ca l

Unde rg round

Histor;cal

Ullde rg round

Historical

Unde rg round

Histor;cal

lInde rg round

Histor;cal Historical Historical Historical Hi stor; ca l Hi stor; ca l

Unde rg round Underground Unde rg round Unde rg round Unde rg round Unde rg round

His tor; ca l Histor;cal Histor;cal Hi s tor; ca l Hi s tori ca l Histor;cal

Unde rg round unde rg round Unde rg round unde rg round Unde rg round unde rg round

Hi s tor; ca l Histor; cal possible possible Ope rat; ng Ope rat; ng

unde rg round underground Open-Cut Open-Cut Open-cut Tai lings Re-Treatment Tai lings Re-Treatment

COMPANIES: OREBODY: Black Jack COM~1ENTS

PRESENT OPERATORS: C T. Mines Ltd.

***

rOB

***

-AGPS--lIIIIIIIIIII

psd--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - -... EQUITY 50.00 50.00

pRESENT OWNERS: Mines Ltd. C T. Ni c ke L Mi ne s Ltd.

r.

COM~'ENTS

OREBODY: B ri LLi ant COMMENTS

PRESENT OPERATORS: Ranger ExpLoration N L. PRESENT OWNERS: AustraLmin HoLdings Ltd.

EQUITY 40.00

Ranger ExpLoration N L.

60.00

r.

COMMENTS Former Ly Ltd.

A.O.G.

Mi nera Ls

OREBODY: Highway COMMENTS

PRESENT OPERATORS: Pacific GoLdmines N L. EQUITY 60.00 40.00

PRESENT OWNERS: North QueensLand Resources N L. Pacific GoLdmines N L.

r.

COMMENTS

PRODUCTION:

-----------

CUMULATIVE PRODUCTION
GOLDCkg) 206,845

RECOVERED GRADECg/t) 33.88

COMMENTS

MAIN PRODUCTION PERIODS: 1871-1918, C1932-1950) , RESOURCES: DATE

OREC'OOOt)

Sep t 1 986 495

GRAOE(g/t) 0 •9

GOLDCkg)

CLASSIFICATION

445

Economi c Demonst rated Recoverab Le

t

BLack Jack

PRE-MINE RESOURCE SIZE: M GEOLOGY: PROV INCE: BLOCK: Tasman Fo Ld Be Lt PROVINCE: Thomson Orogen SUB-PROVINCE: LoLworth-Ravenswood BLock HOST ROCKS: Mount Windsor VoLcanics FeLsic to intermediate Lavas and pyrocLastics, minor sediments. Host to ~,eathered ?voLcanogenic massive suLphide mineralisation Late rite at Highway.

in

barite-rich

-AGPS--'"

---------------1IIIllU!lI

-=-==-MICROGRAPHICS BUREAU

Ravenslolood Granodiorite Comp lex CPhase I I) Biotite granodiorite. ~lineralisation comprised auriferous quartz sulphide veins in 2 cognate fissure sets in granodiorite adjacent to a contact with charters Towers Metamorphics. Charters Towers Metamorphics Schist, slate, phyllite, altered limestone. Host to minor dyke-associated mineralisation. g ranodi 0 ri te.

Crops out adjacent to

mineralised

AGE: palaeozoic Early Devonian AGE: palaeozoic Late Silurian STRUCTURAL FEATURES MAJOR: Faulting, STRUCTURAL!STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY MAJOR: plutonismCGranite) , ~lINOR: VolcanismCFelsic) , AGE OF INTRUSION: pa laeozoic Ear ly Devonian AGE OF INTRUSION: palaeozoic Late Si lurian METAMORPHISM: Charters Towers Metamorphics ~/ere dynamo-thermally metamorphosed by intrusion of the Ravenswood Granodiorite complex. ALTERATION: The crushed granodiorite within the lodes has been extensiVely replaced by quartz (=si licification). DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. STYLE: Discordant, stratabound , MORPHOLOGY: Irregular, Lenticular, Tabular, AGE OF MINERALISATION: Palaeozoic Early Devonian AGE OF MINERALISATION: Palaeozoic Lute Si lurian DIMENSIONS: OREBODY: Black Jack STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Bri lliant

...

m)

MIN

AVE

MAX 220.0 90.0 150.0

AVE

~lAX

cm )

m )

•

~

[i!]J-AGPS--..

..---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -1lIIlIII8 ( m ) DEPTH OF COVER ( m ) STRIKE LENGTH ( cm ) TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: C larks Moonstone STRIKE LENGTH VERTICAL DEPTH ORE80DY: Cumbe r land

( m ) ( m )

TRUE WIDTH VERTICAL DEPTH ORE80DY: Day Dawn

( cm )

30.0

255.0 1700.0

MIN

AVE

mN

AVE

( m )

MIN ( m ) DEPTH OF COVER ( m ) STRIKE LENGTH ( cm ) 90.0 TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: Golden Alexandra (Washington) MIN ( m STRIKE LENGTH ( m VERTICAL DEPTH ORE80DY: Highway mN ( m STRIKE LENGTH ( m TRUE WIDTH ( m VERTICAL DEPTH ( m DEPTH OXIDATION ORE80DY: Identity MIN ( m VERTICAL DEPTH ORE80DY: Imperial MIN ( m STRIKE LENGTH ( m VERTICAL DEPTH ORE80DY: John Bull MIN ( m ) STRIKE LENGTH 60.0 ( cm ) TRUE WIDTH ( m ) VERTICAL DEPTH ORE80DY: Just-In-Time MIN (m ) VERTICAL DEPTH OREBODY: Lady Maria mN (m ) STRIKE LENGTH ( cm ) TRUE WIDTH (m ) VERTICAL DEPTH OREBODY: Moonstone MIN (m ) STRIKE LENGTH 25.0 ( cm ) TRUE WIDTH (m ) VERTICAL DEPTH OREBODY: Moonstone (Cross) MIN (m ) STRIKE LENGTH ( cm ) TRUE WIDTH VERTICAL DEPTH (m) OREBODY: North Australian MIN (m ) STRIKE LENGTH

90.0 930.0 ~lAX

370.0 100.0 ~lAX

90.0 120.0

AVE

MAX

120.0

2400.0 1200.0 820.0

0.0

AVE

AVE

35.0 AVE AVE

AVE

AVE AVE

AVE

AVE

AVE

MAX

330.0 160.0 MAX

55.0 35.0 30.0 75.0 MAX

300.0 MAX

1000.0 120.0 ~lAX

450.0 120.0 240.0 MAX

210.0 MAX

440.0 15.0 330.0 MAX

900.0 90.0 80.0 MAX

200.0 20.0 160.0 MAX

300.0

Md:

L08

*** (jiJJJ-AGPS

...._ _ MICROGRAPHIeS BUREAU 270.0

VERTICAL DEPTH (m OREBODY: Old Queen Cross STRIKE LENGTH VERTICAL DEPTH OREBODY: Queen

STRIKE LENGTH ( m TRUE WIDTH ( cm ) VERTICAL DEPTH (m OREBODY: Rainbow-Wyndham STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: St. George

( m ) ( cm ) (m)

STRIKE LENGTH VERTICAL DEPTH OREBODY: St. patrick

( m (m

STRIKE LENGTH ( m TRUE WIDTH ( cm ) (m) VERTICAL DEPTH OREBODY: Stockholm (Comstock) STRIKE LENGTH (m) TRUE WIDTH ( cm) VERTICAL DEPTH (m OREBODY: stockholm (Cross) STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Swedenborg

( m ) (m

)

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Victory

(m

)

AVE

MAX 450.0 220.0

MIN

AVE

MAX 1550.0 180 .0 320.0

MIN

AVE

MAX 600.0 90.0 310.0

MIN

AVE

MAX 250.0 320.0

MIN

AVE

MAX 300.0 180.0 210.0

MIN

AVE

MAX 140.0 60.0 290 .0

MIN

AVE

MAX 140.0 90.0 380 .0

MIN

AVE

MAX 400.0 25.0 160 .0

mN

AVE

MAX 600.0 75.0 370.0

MIN

AVE

MAX 360.0 140.0

30.0

( cm )

( cm)

(m (m

15.0

)

STRIKE LENGTH (m) TRUE WIDTH ( cm ) VERTICAL DEPTH (m) OREBODY: We II i ngton-Lord Ne lson STRIKE LENGTH VERTICAL DEPTH

MIN

( m (m

(m

1IIIIIIIIlI

) )

NATURE OF MINERALISATION: Free Mi lling , Massive, oxidised, primary, PRIMARY ORE: Multiple Veins, Vein (Reef) , MINERALOGY: OREBODY: Charters Towers Ore veins have simple typically mesothermal mineral assemblage. Gold occured chiefly as the native metal. Sulphide zone quartz, pyrite, galena, sphalerite; less abundant calcite; rare chalcopyrite, gypsum, bari te, arsenopyrite, native arseni c, te lluri de. Ga lena was strong ly

*** MOB *Mr

-AGPS--....

. . - - - MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - - . correLated with ~oLd content (both decreasing with depth), and was a good indicator mlneraL of goLd mineraLisation. oxide Zone, iron oxide (gossan), cerussite, copper carbonate. OREBODY: Hlghway Very fine-~rained free goLd is erraticaLLy dispersed in a sandy Laterite materiaL wlth irreguLar masses of barite and quartz cemented by Limonite and kao Li ni te. GENETIC CONTROLS: The arrangement of the fissure s)'stems and the mineraLised veins about the projection of the syncLinaL foLd axis from the metamorphics suggests that the fo Lding of the metamorphics and the fracturi ng of granodiorite were produced by the same stress fieLd and that the foLding was the fundamentaL cause of ore L'lcaLisation. The proximate controL of the form of the mineraLised zones appears to have been the structuraL form of the fauLt fissures. Apart from smaLL areas of enrichment of some oreshoots at intersections with normaL fauLts, the form of the orebodies was apparently not influenced by changes in host rocks or intersections wHh dykes or other structures. GENETIC ~lODELS: The orebodies were deposited at intermediate depth at 260-340 de!;! C from hydrothermaL fluids associated with the Late stages of granodionte intrusion =mesothermaL deposition. FLuids were rich in Si02, with Lesser but significant H2S content, and carried aLkaLi carbonates and base l'letaLs. MuLtipLe intrusion Led to fracturing/foLding of the countrY rock and earLier intrusive phases. The originaL fissures are not simpLe p Lanes formed at one time, but are the resuLt of severa L episodes of movement. The overaLL moVement on the fissures appears to have been tensionaL with dispLacement ranging from 1 to 12 m. Fluids were subsequently injected aLong the fissure pLanes. Oxygen isotope aata are consistent with a magmatic-hydrothermaL origin of the ore forming fluids reLated to intrusion of the Late fe Lsic phase of the Ravenswood Granodiorite compLex (GoLding & others, 1987). The reLative enrichment of goLd in the upper portions of the Lode fissures is the effect of faLLing temperature on mineraL soLution equi Libria. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Bri Lliant The BrilLiant Lode system was the most productive of the fieLd, accounting for 31~ of totaL buLLion production. The s¥stem comprised the main Lode running transverseLy to the syncLinaL aX1S pLus numerous paraLLeL subsidiary fissures. The highLy curved and irreguLar form of the fissures suggests strons tensionaL tearing across the sync LinaL axis, producing a drag fo Ldlng or shear l.ink reLationship. The main shoots on the system were the main BriLLiant shoot and the Victoria shoot on the main Lode, pLus four shoots on branch veins - the Victoria and Queen, CaLedonia New QUeen Cross and TaLisman. The Victoria shoot Lay 300 m to the east of the main Lode. The Victoria and Queen, CaLedonia, and New Queen Cross shoots were a partLy overLapping group of subsidiary fissures at the far eastern end of the Bri LLiant Lode sys tern. OREBODY: charters Towers REGIONAL SETTING: LOLWORTH-RAVENSWOOD BLOCK The LoLwcrth-Ravenswood B Lock consists of earLy paLaeozoic voLcanicLastic sediments and caLc-aLkaLine voLcanics and precambrian or earLy paLaeozoic metamorphics, intruded by two Large composite bathoLiths of Ordovician to Devonian age. An extensive Cambrian-Ordovician voLcanic sequence trends east-west

-------------------------IMiJI-AGPS--..

...- - MICROGRAPHIeS B U R E A U - - - - - - - - -...~~---.-..--.... along the southern margin of the block. Lower section = clastic sediments apparently derived from a metmorphic source area; upper section = suite of caLc-aLkaLine voLcanics and voLcanicLastic sediments. Metamorphic rocks occur in the western extremity of the bLock; Limited occurrences of simi Liar metamorphics in the northern part of the bLock include the Charters Towers Metamorphics. The sedimentary-voLcanic sequence is considered to represent a remnant of a Cambrian-Ordovician isLand arc SYstem which developed on oceanic crust adjacent to the proterozoic craton (now represented by the Georgetown InUer), from which it was separ~ted a marginal sea. The metamorphi cs are possi bLy deformed deposits of the margi na L sea. Much of the LoLworth-Ravenswood B Lock is occupied by composite granitoid bathoLiths. The earLiest intrusions, comprising the oLder phase of the composite Ravenswood Granodiorite CompLex, were empLaced in association with orogenesis in the mid-Ordivician. After orogenesis the block moved to a transitionaL tectonic regime. The block was a structuraL high in the si Lurian-Devonian, when 3 other major granitic batholiths were emplaced during a second stage of orogenesis (Bowning orogeny). These were: younger phase of the Ravenswood Granodiorite Complex LoLworth IQneous compLex, and DUlTlbano Granite. The bathoLiths are 1ntruded by smaLler generally discrete pLutons, stocks and compLaxes of Late carboniferous to EarLy Permian age wnich are part of the north Queens Land volcanic/pLutonic province (See Deposit No. 12 Kidston), a major widespread episode of igneous activity after which the LoLworth-Ravenswood BLock was finaLly stabi lised. AS SOC IATED MINERALISA nON Four categories of goLd mineraLisation occur: 1./ Minor goLd mineraLisation occurs i;, voLcanogenic massive suLphide deposits associated with the cambrian-Ordovician sedimentary-voLcanic sequencp of the pre-cratonic stage (e.g. Highway, Liontown, Lucky Break). 2./ Minor goLd mineraLisation is associated with Ravenswood Granodiorite compLex phase I (e.g. Hi llsborough, Kirk, Seventy-Mi Le). 3.; Major goLd mineraLisation occurs in auriferous quartz-suLphide deposits associated with Ravenswood Granodiorite CompLex Phase 11 of the transitionaL-tectonic stage (e.g. charters Towers, DisraeLi, some Ravenswood, some Cape River, many deposits between Charters Towers and Ravenswood) • 4./ Gene ra l Ly sma LLe r than 3./ but more numerous and hig he r-g rade go Ld deposits are associated with intrusions of the voLcanic/Plutonic province (e.g. some Ravenswood, Mount Leyshon, Mount Wrigh t ); See Deposit No. 12 Kidston. The RaVenswood Granodiorite CompLex is exposed over 8000km2 and comprises mainLy I-type granitoid bodies empLaced during 2 main intrusive epochs. Each epoch proceeded from a main gl'anodiorite or tonalite phase - biotite i;lrandiorite, hornbLende i;lranodiorite, and biotite-hornbLende i;lranod10rite - to Later more Sl Licic phases - biotite granite and adamelL1te. Diorite and gabbro are widespread but minor components. ALL rock types are in pLaces strongLy foLiated. REGIONAL SETTING: CHARTERS TOWERS GROUP The Charters Towers Group of deposits is distributed in a zone 15km wide x 80km Long extending from Charters Towers to Ravenswood. The zone coincides with the main axis of doming of the bathoLith, and was eVidentLy an important Locus of tension during the RGC phase I1 intrusive episode. Deposits are simi Lar to but much smalLer than Charters Towers, comprising generally narrow mesothermaL quartz-sulphide veins occupying fissures in granodiorite or reLated rocks. GEOLOGICAL SETTING: CHARTERS TOWERS The Charters Towers deposit Lies within biotite granodiorite adjacent to a contact on the northwest 101 ith Cha rte rs Towe rs Metamorp hi cs. In the contact zone the granodiorite is foliated parallel to the metamorphic

1I:mma

*** A09 *,H

[jil-AGPS---

fliIElIII~--MICROGRAPHICS BUREAU--------~--------~---m foLiation. The Metamorphics have been dynamicaLLy metamorphosed and strongLy folded along northwest-trending axes; the ore deposits are spatiaLly reLated to projections of the fold axes from the Metamorphics into the g ranodi orite. The granodiorite is cut by abundant dykes and irreguLar bodies of compositions ranging from felsic to mafic. Sequence of empLacement, b~~ed on isotopic dating (see Geochronology) was:i) Granodiori te (Ravenswood Granodiorite Coml' lex Phase 1). ii) 5 series of dykes, compositions ranging from apLitic granite to Qabbro • lii) 2 s~ries of basalt dykes. iv) Granodiorite (Ravenswood Granodiorite Complex phase 11). v) Auriferous lodes. vi) porphYritic hornblende-andesite dykes, abundant in the auriferous areas. The granodiorite is strongly fractured. 3 main fault systems, in chronologicaL order, are: i) north northwest-striking, east northeast-dipping @ 20-50 deg, most between 27-36 deg. ii) east or northeast-striking, north or northwest-dipping @ 23-50 deg (except Day Dawn). iii) smalL verticaL fauLts, random orientation. The cognate sets i ) and ii) are normal fault systems lying symmetrically about the projection of a synclinal axis from the Metamorphics. The orebodies occurred as simple or compositp bodies whoLLy or partly occupying fissures of the 2 cognate fracturr; systems and to a much lesser extent the vertical faults. The m-;neralised veins are disposed in 2 groups Which lie aLong the projections of 2 fold axes from the Metamorphics:- a northwest-p lunging syncLine (referred to above) which forms an indentation in the granite contact, passes throught the Bri lliant group of lodes and an inferred antic linal axis to the southwest passes through the Day Dawn group of lodes. The major lodes of the field, including the two dominant lodes BrilLant and Day Dawn, occupied fissures of the east-west system. Average dip was 30-40 deg north, except for Day Dawn (average 50 deg, max 65 deg). The ma~or fissures commonly split into two or more separate paralleL or branchlng sub-branches, forming composite Lode systems. The ore zones apparently formed a series of cymoid LoojJs. The north-south fissure system hosted most of the smaLLer Lodes in single discrete reefs. Average dip was 27-36 deg E. Lodes consisted of one or more quartz-sulphide veins plus aLtered crushed granodiorite within well-defined sLickensided fault walls. Thickness of most lodes ranged between 30-180cm. Grades decreased steepLy with depth; average values feLL from 55 Q/t AU near the surface to about 14 g/t Au at the greatest depth of stoplng (900m). Only the 5 Largest reefs were fo LLowed to dejJths greate r than 330m. stocks and compLexes of Late Carboniferous to Early I'ermian age which OREBODY: Day Dawn . The Day Dawn Lode system accounted for 21? of production from the field. The lode orientation departs from the general pattern: the dip is much steeper and the Lode course follows that of a pre-existing mafic (diorite) dyke. The dyke apparently acted as a pLane of weakness during shearing, aLthough not coinciding with a principal shear plane. The dyke is brOKen, slickensided and partly repLaced by lode material. The lode comPrised four main shoots and severaL minor shoots. Ore zones Were distributed ;n an en echelon pattern, resuLting from the hanging wall veins taking over from footwall veins progressing up from shear to shear. OREBODY: Hi ghway Gold mineralisation is associated with barite-rich Laterite within strongLy Sheared rhyoLitic lavas and pyrocLastic rocks of the Cambrian-

-AGPS

--_.-11

.,.,..,-- MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - - - . Ordovician Mount Windsor voLcanics. The VoLcanics are host to strati form voLcanogenic massive suLphlde deposits at Liontown, ThaLanga, Warrawee. The VoLcanics have a prevaLent east-west strike and southerLy dip; in the deRosit region bedding and cLeavage strike anomaLously northeast. Volcanic textures indicate that strata are locaLl)' overturned. Mineralisation is hosted by an oval-shaped area of laterite enclosed to the east by siliceous rhyolitic flows and pyrocLastics and to the west by massive banded hematite-goethite-quartz rocks. Along strike from the lateri':e the rocks are porous tuffs '4ith intei"bedded cherty lenses. A zone of quartz-pyrite veinin~ and siLicification extends from the deposit lnto the rhyolite unlt. The ironstone IJnit contains relic pyrite textures and may represent a weathered massive pyrite body. The laterite profi le comprises a thin ferruginous capping, a thick mottled zone, the main host to mineralisation, and an underlying pallid or leached zone. Kay (1987) postuLated a submarine voLcanogenic origin in which gold and barite were originally precipitated in the subsurface stringer zone of a smaLL submarine volcanic vent. The adjacent si Liceous ironstone unit is interpreted to be the weathered remains of a submarine pyritic exhalite. The iron-rich composition favoured deep acid weathering, laterite deveLopment and gold concentration during subsequent erosion. REFERENCES: Blatchford A. , 1972 Charters Towers GoLdfield. IN Edwards A.8.(ed) - Geology of Australian ore deposits. 5th Empire Mining & MetaLLurgicaL Congress, AustraLia & New Zea land, 1953, Me lbourne. Atomic Energy in Australia 15(4) P796-806 Brooks J.H. , 1960 precambrian - The Charters Towers, Cape River and Woolgar goLdfieLds. Geological Society of Australia. JournaL 7 p75-76 Cameron W.E. , 1909 charters Towers goldfield. Notes on some of the reefs. Queensland Government Mining JournaL 10 p222-228 Connah T. H. , 1952 Black Jack gold mine - Charters Towers. Queensland Government Mining JournaL 53 p656-659 Connah T. H. , 1960 Gold workings, 'The HighwaY' lease, Charters Towers. Queens land Government Mi ni ng Journa L 61 p461-463 oenmead A. K. , 1935 Swedenborg goLd mine. Queens land Government 36 p272-274

r~i

ni I1g Journa l

oenmead A.K. , Levingston K.R. , 1951 Report on the Black Jack gold mine, Charters Towers.

*,~*

C09 ***

e-----------------------~-AGPS--

..

....--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -...... Queensla"d Government Mining Journal 52 p128-133 Dunnet D. 1986 OPen pit gotd potential - Charters Towers vein systems. IN Gold EXploration and development, north QUeens land. AusIM~1 Conference, Charters To' ers, August 1986. Extended abstracts. AusIMM 1v p18-19 Golding 5.0. , Wilson A.F. , 1980 The appLication of oxygen isotope studies to the occurrence of gold mineraLi zation in eastern Australia. IN AusIMM Conference, New zeaLand, May 1980. AusIMM. Conference Series 9 P67-80 Golding 5.0. , wilson A.F. , 1981 An oxyg~n and carbon isotopic study of some gold deposits of eastern Australla. AusIMM. proceedings 278 P13-21 Golding 5.0. , wilson A.F. , Scott M. , Anderson P.K. , Waring C.L. , Flitcroft M. , Rypkema H.A. , 1987 Isotopic evidence for the diverse origins of goLd in Queens Land. IN Herbert H.K. (ed) - GoLd in Queens Land. proceedings of one-day symposium, university of Queens land, June 1984. university of Queens Land. Department of GeoLogy. Papers 12 (1) p65-83 Heidecker E.J. , 1978 GoLd and siLver enrichment in the Burdekin goLdfields - impLications for a second generation mining and metalLurgical technology. In AusIMM AnnuaL Conference, North Queensland, 1978. AusIMM. conference Series 7 P67-72 Hill W.H. , 1982 The appLication of cyanide-Leaching to ore from the Highway gold mine, Charters Towers. IN WithnaLL I.W.(Ed) - 1982 fieLd conference, Charters Towers-GreenvaLe area. 1-3 May 1982. GeoLogicaL Society of AustraLia. QueensLand Division 1v p24-27 IS haq S. , 1 986 GoLd fever hits Charters TowerS. QueensLand Government Mining Journal 87(1018) P346-347 Jack R.'_. , 1879 GeoLogy and mineraL resources of the district between Charters Towers and the coast. Geo logi ca L Survey of Queens Land. PubLication 1

Kay J.R. 1982 Notes on the geoLogy of the Highway goLd mine, charters Towers. IN withnalL I.W.(Ed) - 1982 fieLd conference, charters Towers-Greenvale area 1-3 May 1 982. GeologicaL society of AustraLia. Queensland Division

..._ _

~

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[[ii]]-AGPS - _..

.,.----MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - -...- -..... 1v p22-23 Kay J. R. , 1987 The Hignway gold m)ne, charters Towers - submarine volcanogenic goldbarite stringer mineralisation, modified by lateritic weathering. IN Kerbert :~.K. (ed) - Gold in Queens land. proc. of one-day symposium, university of Qld, June 1984. university of Queens land. Departmen~ of Geology. Papers 12(1) p111-125 Keid H.G.W. , 1938 Try Again area - Charters Towers. Queensland Goverl'Jnent Mini;1g Journal 39 p159-161 Lev i ng s to n K. R• , 1981 Geological evolution and economic geology of the Burdekin River region, Queens land. Bureau Mineral Resources, Australia. Bulletin 208 Le'J)ngston K.R. , 1972 ore deposits and mines of the Charters Towers 1 :250 000 sheet area, north Queens land. GeologicaL Survey of Queens land. Report 57 Levin~ston K.R. , 1986 some lmportant historicaL infLuences on the Charters Towers goLdfieLd. IN Gold exploration and deveLopment, north Queens Land. AusIMM Conference, Charters Towers, August 1986. Extended abstracts. AusIMM. North Queensland Branch 1v p69-73

Marks E.O. , 1913 outside mines of Charters Towers goLdfield. GeologicaL Survey of QueensLand. publication 238 Ma r ks E. O. , 1 912 outside mines of Charters Towers goLdfield. QueensLand Government Mining JournaL 13 p148-152 r-brton C.C. , 1936 Rainbow No.2, charters Towers. Queens Land Government Mining Journa l 37 P122-123 ~brton C.C. , 1936 Charters TOl4ers low grade deposits. Queensland Government Mining Journal 37 P229-232

r-brton C.C. , 1936 Black Jack G.M. Co. NL, charters Towers. Queens land Government Mi ni ng J ourna l 37 p299-303 r-brton C.Co, , 1937 swedenborg mine, Charters TOWers.

*** E09

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. . AGPS ...._ ...

BUREAU

.----MIC~OGRAPHICS

-m

Queens Land Government ~li ni ng Journa L 38 P229-230 Morton c.c. r 1937 Kroko mine, Cnarters Towers. QueensLand Government Mining JournaL 38 p353-354 Morton c.c. , 1938 BLack Jack mine. Queens Land Government Mi ni ng Journa L 39 p334 Morton c.c. , 1944 No. 2 SE Victoria cLaim, charters Towers. Queens Land Gove rnment Mi ni ng J ourna L 45 P238-239 Morton c.c. , 1945 LittLe Red BLuff, Charters Towers. Queens Land Government Mi n; ng J ourna L 46 p234 ~lorton c.c. ,1938 washington reef, charters Towers. Queens land Government Mining Journa L 39 P332-334

peters S.G. Re lati ons hip my loni tes at proceedings, AUSIMM 1v p363-36"1

, GoLding S.D. , 1987 of goLd quartz mineraLization to granodioritic phases and Charters Towers go Ldfi e Ld, northeastern Queens Land. IN Pacific Rim Congress 87, GoLd Coast, Queensland, Au9 1987.

Rands W.H. , 1913 charters Towers deep-sinking oroposaL. QueensLand Government Mining JournaL 14 p587-592 Re i d J. H. , 1 914 charters Towers goLdfieLd. Reefs worked in the past. QueensLand Government Mining JournaL 15 P356-35B Re id J. H. , 1 915 charters Towers goLdfieLd. RevivaL of mining. Queens Land Government Mining Journa L 16 p318-319 Re i d J. H. , 1 917 The Charters Towers goLdfieLd. parts I-V. QueensLand Government Mining JournaL 18 p55-66; 122-31 ;166-75;21 5-26; 273-85 Re id J. H. , 1 91 7 The Charters Towers goLdfieLd. GeoLogicaL Survey of QueensLand. 256 RusseLL R.T.

...

pubLication

, 1986

-=-

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[li]j_AGPS - _..

(IDIIII--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - . ExpLoration at the Highway goLd deposit. IN GoLd expLoration and deveLopment, north Queens Land. AusIMfl Conference, Charters Towers, August 1986. Extended abstr~cts. AusIMM. North Queens Land Branch 1v P74-75 Wyatt D.H. , paine A.G.L. , CLarke D.E. , Gregory C.M. , 1971 GeoLogy of the Charters Towers 1:250 000 Sheet area. Bureau MineraL Resources, AustraLia. Report 137

, Harding R.R.

0000000000000000000000000000000000000000

-AGPS----.I

~-- MICROGRAPHICS BUREAU--------------~----__. DEPOSIT:

20

MOUNT LEYS HON

DEPOSIT IDENTIFICATION:

PRINCIPAL COMMODITIES: Au ,

A9 ,

MINES: GoLden Horn, Mount Leyshon , OREBODIES: GoLden Horn, Mount Leyshon ,

Mount Leyshon (HistoricaL O/Cl ,

GROUP: permo-Car'boniferous Igneous Group COMMENTS: See Deposit No. 19 Charters Towers for regionaL setting of LoLworth-Ravenswood Block; Deposit 12 Kidston for regionaL setting of Permo-Carboniferous igneouG group. LOCATION: LA TITUDE: 20 16 250K SHEET: SF55 2

LONGITUDE: 14616 100K SHEET: 8157

ADMINISTRATIVE SUBDIVISION: mNING DISTICT: Charters Towers MINING FIELD: charters Towers LOCALITY: DEV ELOPMENT HISTORY: DISCOVERY METHOD Prospecti ng

DISCOVERY YEAR 1871 OPERATING STATUS AT 1987 MINE Mount Leyshon GoLden Horn Mount Leyshon ~lount Leyshon

STATUS Operating possibLe Operating HistoricaL

MINING METHOD Heap-Leach Open-Cut Open-Cut Open-Cut

CO~lPANIES:

OREBODY: Mount Leyshon COMMENTS

PRESENT OPERATORS: Pan Austra Lian Mining Ltd.

,~*,~

HO 9

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1Ir.rmm--------------------~-AGPS--

..

pma:--

MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - - - - - - - -.... EQUITY 100.00

pRESENT OWNERS: Pan Australian Mining Ltd.

r.

COMMENTS

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 164,837

GOLDCkg) 1,455

RECOVERED GRADECg/t) 8.82

COMMENTS

MAIN PRODUCTION PERIODS: 1887-1916 , 1987- , RESOURCES:

---------DATE

OREC' OOOt)

GRADECg/t)

GOLD(kg)

CLASSIFICATION

Dec 1987

3,900

1.4

5,460

Dec 1987 Dec 1987

1,700 6,300

1.0 1.8

1,700 11,340

Econom - Meas Econom Econom

c Demonstrdted Recoverable red Re cove rab le c Infe rred c Demonstrated Recoverable

o/c o/c o/c

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fold Belt PROV INCE: Thomson Orogen SUB-PROVINCE: Lolworth-Ravenswood Bloc k HOST ROCKS: Mount Leyshon Volcanic complex Partly intrusive rhyolite and porphyry; minor dacite, trachyandesite, andesite, breccia, agglomerate. ErraticaLly distributed gold mineralisation is associated with widespread pyrite disseminations, segregatlons, and vein and fracture fillings in volcanic breccias and rhyoLitic intrusives. Cape River Beds Jointed, foliated phyllite and quartzite. Intruded by mineralised volcanic centre Granodiorite Comp lex.

along

contact

with

Ravenswood

Ravenswood Granodiorite Comp lex Fine- to medium-grained leucocratic granite, grading to porphyritic microgranite and aplite. Intrudes main phase of Ravenswood Granodiorite Complex along contact zone with Cape River Beds; is cut by mineralised volcanic centre. AGE: pa laeozoic Late Carboni ferous STRUCTURAL FEATURES

-AGPS---·

.....--MICROGRAPHICS

BUREAU--------------------.

STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, SIGNIFICANT: Fault/Fault, IGNEOUS PROXIMITY MAJOR: sub-VolcanismCFelsic porphyry) , VolcanismCFelsic) , SIGNIFICANT: plutonismCGranite) , AGE OF INTRUSION: palaeozoic Early Devonian METAMORPHISM: Grade of metamorphism of Cape River Beds is lo~ greenschist - lo~er than in the Cape River region to the ~est. Metamorphism is considered to be related to intrusion of Ravenswood Granodiorite Complex. ALTERATION: ~lineralisation was accompanied by intensive hydrothermal alterationsulphidation, silicification, carbonation. DEPOSIT CHARACTERISTICS: -'

TypES: Auriferous quartz veins in felsic volcanic breccia pipe. STYLE: Discordant, stratabound , MORPHOLOGY: Pipe-Like, AGE OF MINERALISATION: palaeozoic Late Carboni ferous DHIENSIONS: OREBODY: Mount Leyshon CHistorical O/C) MIN m STRIKE LENGTH m TRUE WIDTH m VERTICAL DEPTH

AVE

I1AX 175.0 60.0 40.0

NATURE OF MINERALISATION: Disseminated, Free Mi lling , oxidised, primary, PRIMARY ORE: 8reccia , MINERALOGY: ORE80DY: Mount Leys hon Sulphide ore: free gold, quartz, chlorite, carbonate, pyrite, chalcopyrite, sphalerite, galena, trace copper and bismuth. Gold occurs as sub-spherical blebs up to 150 microns in diameter within the sulphides in the breccia matrix. GENETIC CONTROLS: Emplacement of the volcanic complex appears to have been structurally controlled as it occurs at the intersection of major northeast and minor north~est-trending lineaments. Within the dep.osit, higher gold concentrations tend to be confined to particular joint systems, and also favour rock carrying large numbers of small veins, not necessari ly the

1lImllII

riiID -AGPS _ _Ill

p;II-- MICROGRAPHICS BUREAU ...- - - - - - - - - - - - - - - - - -..... most pyritic material. GENETIC MODELS: Epithermal vein deposit formed in continental Jllatform settin!) in a transitional tectonic regime. Mineralisation is associated \-nth hydrothermal activity representing the waning stages of post-oragenic subaeria l volcanismtsubvolcanism. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Mount Leyshon Mount LeYshon lies due south of Charters Towers in the southwestern portion of the Lolworth-Ravenswood Block. The deposit occurs in a volcanic complex affi liated with the Permo-Carboniferous volcanict plutonic province. The complex was emplaced at the intrusive contact between Ravenswood Granodiorite complex and Cape River Beds. The Cape River Beds together with Mount Windsor Volcanic~ are exposed in a broad east-west trending be lt alon!) the southeastern margin of the block. The Cape River Beds in the deposlt re!)ion are jointed and fractured phyllite and impure quartzite, follated in an east-west direction and dipping south. In the contact zone the main phase of granodiorite is intruded by a body of the late leucocratic phase of the batholith, which occurs mostly near the batholith margins. Gold mineralisation is associated with a breccia pipe in a volcanic complex which cuts across the contact zone. The volcanic suite consists of rhyolite and dacite porphyry - partly intrusive - and agalomerate, minor dacite, andesite and trachYandesite, and rhyolite breccla. The fragmental rocks include material derived from the granite and the metasediments. Dykes of altered flow-banded quartz-feldspar porphyry intruding granodiorite northeast of Mount Leyshon may a lso be re lated to the vo lcani c camp lex. The dykes are partly greisenised and stained by Fe-oxides along partings parallel to the flow bandi ng. . The gold mineralisation is associated with widespread sulphide, mainly pyrite, impregnations of volcanic breccias and intrusive rhyolitic porphyries. The mineralisation takes the form of auriferous quartz-sulphide cavity coatings, matrix replacement, disseminations, and vein and fracture fi llings. The heavi ly oxidised surface zone is permeated with limonite veins and stringers. Although grades are erratically distributed, 3 ore zones were rich enough to have been worked in the past by open cut. REFERENCES: Levi ngston K.R. , 1972 Ore deposits and mines of the Charters Towers 1 :,~50 000 sheet area, north Queens land. Geological Survey of Queensland. Report 57 Ly nc h J. E• , 1 986 Heap leach development of the Mt Leyshon gold, silver deposit. IN Gold exploration and developments, north Queenslana. AusH1M Conference, charters TOI./ers, August 1986. Extended abstracts. AusHlfl. North Queensland Branch 1v P115-119 Morrison 6.W.

, Teale 6.5.

, Hodkinson I.

, 1987

*,~,~

KO 9

,hh',

-AGPS--'"

6I/iIIIIIlI-- MICROGRAPHICS BUREAU-------------------

IIIIZZII

GeoLogy and goLd mineraLisation at Mount Leyshon, north QueensLand. IN Proceedings, pacific Rim Congress 87, GoLd Coast, QueensLand, August 1987. Aus IMM 1v p777-780 Morton C.C. , 1932 Mount Leyshon, charters Towers district. Queens Land Government Mi ni ng Journa L XXXIII P22'i-227 ~lorton

C.C. , 1939 Mount Leys hon. Queens Land Government Mi ni ng Journa L 40 p400-401 0000000000000000000000000000000000000000

1lIIIIIllIlII

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L09 **i<

fiilll_ AGPS - _..

....--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - . . . DEPOS IT:

DISRAELI

21

DEPOSIT IDENTIFICATION: SYNONYMS: cornishman, Rishton , PRINCIPAL COMMOD,TIES: Au , Ag , MINES: Disraeli , OREBODIES: Disraeli , Joes Delight, GROUP: charters

TO~lers

Group

COMMENTS: See Deposit No. 19 Charters Towers for regional setting of Lolworth-Ravenswood B lock and charters Towers group. LOCATION: LATITUDE: 20 8 2S0K SHEET: SF55 2

LONGITUDE: 146 32 100K SHEET: 8257

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: charters Towers MINING FIELD: Charters Towers LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METfIO[l prospecti ng Dri lling Geo logy

DISCOVERY YEAR 1880 1983 1983 OPERATING STATUS AT 1987 ~lINE

Disraeli Disraeli

STATUS Hi stori ca l possible

MINING METHOD Underground Open-Cut

CO~lPANIES:

OREBODY: Disraeli PRESENT OPERATORS: Strategic Resources Holdings Ltd •

...

_~

COMMENTS strategic Resources Hlding s

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....--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - -...• Ltd is whoLLy-owned by North QueensLand Resources N L.

EQUITY 50.00 50.00

pRESENT OWNERS: Newmont proprietary Ltd. North QueensLand Resources N L.

r-

COMMENTS

PRODUC nON: CU~lULAnVE

PRODUCTION (TO DEC.1986):

ORE(t): 9,790

GOLD(kg) 261

RECOVERED GRADE(g/t) 26.65

COMMENTS

MAIN PRODUCTION PERIODS: H81-1942 , 1988- , RESOURCES: DATE

ORE (' OOOt)

GRADE(9/t)

GOLD( kg)

CLASSIFICATION

Dec 1987 Dec 1987

4,250 1,108

3.0 3.5

12,750 3,878

Sub-Economic Inferred In-Situ Sub-Economic Inferred In-Situ

o/c o/c

DisraeLi totaL Joes DeLight

PRE-MINE RESOURCE SIZE: S GEOLOGY: PRO'! INCE: BLOCK: Tasman FoLd BeLt PROVINCE: Thomson Orogen SUB-PROV INCE: Lo Lworth-Ravenswood BLock HOST ROCKS: Ravenswood Granodiorite CompLex Phase I I Biotite granodiorite. Mineralisation comprises auriferous quartz 9 ranodi ori te.

sulphide

veins

in

fissures

in

AGE: paLaeozoic EarLy Devonian AGE: Pa laeozoi c Late Si luri an STRUCTURAL FEATURES MAJOR: FauLting, STRUCTURALlSTRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY MAJOR: P lutoni sm (Grani te) ,

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AGE OF INTRUSION: pa Laeozoic EarLy Devonian AGE OF INTRUSION: palaeozoic Late Si Lurian DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. STYLE: Discordant, stratabound , MORPHOLOGY: Irregular, Lenticular, AGE OF MINERALISATION: pa Laeo zoi c Ear ly Devoni an AGE OF MINERALISATION: pa Laeozoic Late si Lurian DIMENS IONS: OREBODY: DisraeLi STRIKE LENGTH TRUE WIDTH DOWN-DIP DEPTH

m m m

MIN

AVE

MAX

650.0 9.0 75.0

NATURE OF MINERALISATION: Disseminated, Free MiLLing, PRIMARY ORE: Vein (Reef) , MINERALOGY: GEOLOGICAL SETTING OF MINERALISATION: OREBODY: DisraeLi Disraeli was the Largest of a number of deposits worked at Rishton near the Burdekin River 40 km east-southeast of Charters Towers. A northe<\sterLy-trending belt of Late Carboniferous feLsic to intermediate voLcanics overLies the granodiorite west of the deposit area. Mineralisation was simi Lar to that at Charters Towers, comprising muLtipLe auriferous quartz suLphide fissure fi LLings in the main granodiorite phase of Ravenswood Granodiorite Comp lex Phase Il. RE FERENC ES: Levi ngston 1<. R. , 1981 GeoLogicaL evoLution and economic geoLogy of the Burdekin River region, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 208 Levingston K.R. , 1972 Ore deposits and mines of the Charters Towers 1:250 000 sheet area, nort.h Queens Land. GeoLogical Survey of Queens Land. Report

57

_ _ _ _ _ _ _ _ _ _ _ _ _ t,** _A10_***_ _ _ _ _

..

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...--MICROGRAPHICS BUREAU - - - - - - - - - - - - - -...- - - - - - - - . wyatt D.H. , paine A.G.L. , Clarke D.E. , Gregory C.M. , 1971 Geology of the charters Towers 1 :250 000 Sheet area. Bureau Mineral Resources, Australia. Report 137

, Harding R.R.

00000000000000000 00000000000000000000000

_______________....-

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DEPOSIT:

22

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RAVENSWOOD

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: AU , Ag , MINES: Deep Mines, Duke Of Edinburgh, General Grant, Golden Hi II , Grant And Sunset Extended, London , London North , Mount Wright , Ravenswood Ravens~,ood Deep Mi nes , Saratoga , Sunset, OREBODIES: Battle Axe, Black Jack, Buck Reef, Duke Of Edinburgh, General Gordon (Kirkton) , General Grant, John Bull (Sandy Creek) , Little Grand Junction, London, Melaneur , Mount WriQht , New England, Overlander , painus , Ravenswood , Red Streak, Sarsf1eld , ShelmaLier , Sunset , Uni on J ac k , Who' D A Thoug ht It , GROUP: Ravenswood Group COMMENTS: Includes setting of Ravenswood group. See DePosit No. 19 charters Towers for setting of LoLworth-Ravenswood Block. Record covers Ravenswood fieLd reefs in town + reefs in outlying areas: Totley-Kirkton, Donnybrook-Brookvi lle, Mt Wright.

=

LOCATION: LATITUDE: 20 6 250K SHEET: SF55 2

LONGITUDE: 146 53 100K SHEET: 8257

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Charters Towers MINING FIELD: charters Towers LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD Prospecti ng

DISCOVERY YEAR 1868 OPERATING STATUS AT 1987 MINE Golden Hi II Duke Of Edi nburgh Gene ra l Grant London London North Mount Wright RavenswooC!

~~;.:o:3lIIIII

STATUS Historical HistoricaL

MINING METHOD unde rg round underground

Hi stori ca L Historical Historical Historical Historical

underground unde rg round Unde rg round unde rg round unde rg round

-

_ _- - ~ - A G P S - - - "

.-_:lBIII MICROGRAPHIeS Sunset Grant And sunset Extended R~venswood Deep Mines Deep Mi nes Saratoga Ravenswood Ravenswood

BUREAU --~-------------~----..

HistoricaL HistoricaL

Unde rg round Unde rg round

HistoricaL

Unde rg round

HistoricaL HistoricaL Ope rati ng Operating

Unde rg round Unde rg round Heap-Leac h Open-Cut

COMPANIES: OREBODY: Buck Reef COMMENTS

PRESENT OPERATORS: Carpentaria GoLd Pty Ltd.

COMMENTS

EQUITY %

PRESENT OWNERS: M I M HoLdings Ltd.

100.00

PRODUC TION:

CUMULATIVE PRODUCTION
GOLDCkg)

RECOVERED GRADE(9/'c)

744,154

28,025

37.66

COMMENTS

MAIN PRODUCTION PERIODS: 1868-1918 , 1988- , RESOURCES:

PRE-MINE RESOURCE SIZE: M GEOLOGY: PROV INCE: SL')CK: Tasman FoLd Be Lt PROVINCE: Thomson Orogen SUB-PROVINCE: LoLworth-Ravenswood BLock HOST ROCKS: Ravenswood Granodiorite CompLex Phase I I HornbLende-biotite tonaLite. MineraLisation comprised auriferous guartz-suLphide veins in one major and one minor fissure set in tonaLite which 1S regionaLLy intruded by younger more feLsic phases of Ravenswood Granodiorite Comp Lex. AGE: paLaeozoic EarLy Devonian AGE: paLaeozoic Late Si Lurian

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. . - - - MICROGRAPHICS BUREAU ..-_-~~---------------. STRUCTURAL FEATURES MAJ OR: Fractu ri ng , MINOR: Sheari ng , STRUC TURALlSTRA TIGRAPHIC INTERS EC TIONS MAJ OR: Int rus iv e Contact , IGNEOUS PROXIMITY MAJOR: plutonism(Granite) , sub-Volcanism(Felsic porphyry) , AGE OF INTRUSION: palaeozoic Early Permian AGE OF INTRUSION: palaeozoic Late Carboni ferous AGE OF INTRUSION: palaeozoic Early Devonian AGE OF INTRUSION: palaeozoic Late Silurian METAMORPHISM: The Mount Winsdor volcanics were dynamc.-thermally metamorphosed by intrusion of the Ravenswood Granodiorite complex. ALTERAnON: OREBODY: Ravenswood A small proportion of mineralisation occurring in shear zones (Buck Reef, shelmalier Reef) was accompanied by considerable associated hydrothermal alteration - chloritisation, silicification and pyritisation. OREBODY: Mount Wright Rhyolite intrusion was accompanied by shattering and hYdrothermal a lteration of grani te. DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in granitoid. STYLE: Discordant, stratabound , MORPHOLOGY: Irregular, Lenticular, pipe-Like, Tabular, AGE OF MINERALISATION: palaeozoic Early Permian AGE OF MINERALISATION: palaeozoic Late Carboniferous AGE OF MINERALISATION: palaeozoic Early Devonian AGE OF MINERALISATION: palaeozoic Late Si lurian DIMENSIONS: OREBODY: Black Jack TRUE WIDTH VERTICAL DEPTH OREBODY: Buck Reef

a..-.

cm )

m)

MIN 15.0

AVE

••_.......

MAX 70.0 100.0

*f'*

E10

***

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MICROGRAPHICS BUREAU ( m ) STRIKE LENGTH ( cm ) TRUE WIDTH VERTICAL DEPTH (m ORE80DY: Duke Of Edinburgh STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH ORE80DY: Gene ra L Grant

m ) cm ) m )

MIN

MIN

AVE

5.0

mN m ) cm ) 13.0 m ) Cree k) mN ( m ) TRUE WIDTH VERTICAL DEPTH (m) ORE80DY: LittLe Grand Junction MIN m ) STRIKE LENGTH cm ) 8.0 TRUE WIDTH m ) VERTICAL DEPTH ORE80DY: London MIN m ) STRIKE LENGTH cm ) 15.0 TRUE WIDTH m ) VERTICAL DEPTH ORE80DY: Me Laneur MIN cm ) 12.0 TRUE WIDTH m ) VERTICAL DEPTH ORE80DY: ~bunt Wright MIN 20.0 m TRUE WIDTH m VERTICAL DEPTH OREBODY: New Eng Land MIN ( m VERTICAL DEPTH ORE80DY: OverLander MIN m ) STRIKE LENGTH cm ) 12.0 TRUE WIDTH m ) VERTICAL DEPTH ORE80DY: Ravenswood mN m ) DEPTH OXIDATION cm ) TRUE WIDTH 130.0 m ) VERTICAL DEPTH ORE80DY: SheLmaLier MIN m ) STRIKE LENGTH cm ) 15.0 TRUE WIDTH m ) VERTICAL DEPTH ORE80DY: Sunset MIN ( m ) STRIKE LENGTH ( cm ) 30.0 TRUE WIDTH VERTICAL DEPTH (m ) OREBODY: WhO'D A Thought It MIN STRIKE LENG TH TRUE WIDTH VERTICAL DEPTH ( ORE80DY: John BuLL (Sandy

AVE

90.0

AVE

20.0 AVE

AVE

15.0 AVE

AVE

AVE

AVE AVE

MAX

230.0 670.0 47·0 MAX

200.0 135.0 MAX

400.0 10lJ.0 170.0 ~lAX

7.0 240.0 NAX

90.0 40.0 25.0 MAX

400.0 100.0 153.0 MAX

24.0 90.0 ~lAX

30.0 30.0 MAX

175.0 MAX

20.0

62.0 70.0 57.0

AVE

MAX

21.0 50.0 230.0

100.0

AVE

MAX

30.0 AVE

800.0 100.0 100.0 ~lAX

70.0

970.0 80 .0 280.0

AVE

MAX

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. - - - MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -..... VERTICAL DEPTH

( m

27.0

NATURE OF MINERALISATION: Disseminated, Free Mi LLing , Oxidised, primary, Refractory, PRIMARY ORE: Lode (ALterat10n Zone) , pipe, Vein (Reef) MINERALOGY: OREBODY: Buck Reef SuLphide zone: quartz is associated with quartz, some chalcopyrite; sphaLerite and ar~enopyrite are virtually absent. OREBODY: Mount Wnght suLphide ore: pyrite, sphaLerite, minor chaLcopyrite, arsenopyrite. Siderite is common in ore and country rock. OREBODY: Ravenswood suLphide ore: native goLd, quartz, pyrite, gaLena, chaLcopyrite, sphaLerite, arsenopynte, stibnite. Most of the goLd deposits in the Charters Towers-Ravenswood region showed simpLe m1neraL assembLages; Ravenswood was anomalous in having a compLex suLphide mineraLogy. GoLd content closeLy followed suLphide content, and a high proportion was fineLy divided in the suLphides, the remainder assoc1ated with qua rt z. Go Ld grade in su lp hi des reac hed 100 g It. The re frac to ry nature of the ore retarded development of the fieLd as good goLd recoveries were not possibLe without further treatment 1n addition to the standard amaLgamation. Many smaLLer mines were abandoned at the water tabLe, Larger ones sent ores to outside smelters for processing. Ravenswood ores were the first to be processed by concentration and fractionation of the suLphides prior to amaLgamation. concentration yielded a galena-free gold fraction which was then treated by amalgamation and a pynte-chaLcopyrite fraction which was smeLted. But goLd in antimony and arsenic sulphides presented further metalLurgical problems and resulted in very low recovery rates. OREBODY: Shelmalier Ore: goLd was associated with chaLcopyrite and sphaLerite. GENETIC CONTROLS: controLs were probabLy largeLy structuraL, as at Charters Towers. GENETIC MODELS: The main mineraLisation has traditionalLy (Clarke, 1971; Levingston, 1972) been related to the host Si Luro-Devonian granite as at Charters Towers, but Morrison (1987) points out that the vein character and gold association at Ravenswood imply a much shaLLower depth of formation than the mesothermaL Charters Towers deposits and considers the Ravenswood orebodies more likely to be reLated to Permo-Carboniferous sub-voLcanic plugs. MineraLisation of both ages may be present (Murray, 1986). The Buck Reef mineralisation is clearLy oLder than the quartz reef depos1ts and was probabLy formed during east-west shearing at the time of empLacement of the Mosgardies AdamelLite (MiddLe Ordonician). There is no ~,ell-defined equivalent at Charters Towers. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: BLack Jack 8Lack Jack was the onLy rich reef in the east-west trending group of lodes; however the ore grade sections occurred mainLy near intersections with Melaneur reef. Dips were sha Llower than the quoted 34 deg at depth; width aLso decreased with depth. OREBODY: BUc k Reef Buck Reef runs east-northeast from the Sunset-GeneraL Grant area and differed from the quartz lodes in that it consisted of a zone of

..

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BUREAU--------------------.

sheared, mineraLised granodiorite. The granodiorite in the shear zone is crushed, variabLy aLtered, chLoritised, and impregnated with pyrite and quartz veinLets and stringers. The reef carried higher average gold grades than the north-south quartz Lodes, which it evidently pre-dated as it is cut by them; and is therefore considered to represent an earLier phase of mineralization. The workings were concentrated at the eastern end where quartz dominated over sulphides. OREBODY: Duke Of Edinburgh The Duke of Edinburgh Lay to the east of GeneraL Grant. Dips decreased ~,;th depth. OREBODY: GeneraL Grant GeneraL Grant Lay east of Sunset reef and consisted of two main shoots. The first extended from the surface to 133 m, terminating on its southern Limit at Buck Reef. The lower shoot lay south of Buck Reef and was narrower but rich. OREBODY: John BuLL (sandy Creek) The Lodes at Sandy creek are hosted by tonaLite and are similar to but Lower grilde than the Ravenswood lodes. The more important Lodes dip southwest, the minor lodes dip northwest. John BulL was the main reef. OREBODY: London London Lay to the north of Sunset and consisted of two main shoots: an upper, irregular south-pitching shoot and a lower, verticaLLy northpitching shoot. The orebody form was characteri zed by curving, branching fi ssures. OREBODY: Mount Wright The host rock is coarse granodiorite of the Ravenswood Granodiorite compLex which has been intruded by rhyoLite dykes and a~glomerate. MineraLisation occurs within a poorly defined roughLy clrcuLar area of shattered granite, probabLy with an unaLtered granite core, adj acent to rhyoLite intrusion. OREBODY: Ravenswood REGIONAL SETTING: RAVENSWOOD GROUP Ravenswood occurs in granodiorite of the main phase of Ravenswood Granodiorite Complex II in the northeastern portion of the LolworthRavenswood B Lock. East of Ravenswood, the granodiorite is in faulted intrusive contact with a broad northeasterly-trending beLt of Cambrian Mount Windsor VoLcanics; to the north and south the granodiorite is extensiveLy intruded by younger more feLsic siLuroDevonian granites. Late Carboniferous-EarLy permian dioritic intrusives occur to the west of Ravenswood. Regiona L structura L trends foLlow two main directions: east to east-northeast and north-south. Ravenswood Lies at the eastern end of a broad east-west trending structuraL zone which coincides with the axis of doming of the granodiorite batholith. A shear zone extending west from Ravenswood is characterised by myLonitisation, brecciation, Jointing and carbonate veining. 'rhe east to east-nortneast structural system is aLso represented by faulting south of Ravenswood. Major regionaL faults trend north-south in the ~lou;,t Wi ndsor Vo Lcani cs and in the Leucograni te north of Ravenswood. structuraL features are not evident in the granodiorite; w<'ak foliation is attributed to post-crystallisation sheari ng. GEOLOGICAL SETTING: RAVENSWOOD GROUP The host rock to the goLd mineraLisation in the Ravenswood fieLd is fine- and meaium-grained, mostLy even-~rained hornbLendebiotite tona Lite. The tonaLite is cut by doLerlte and fe lsite dykes and occasionaL white quartz bLows. Mineralisation was broadLy simi Lar to that at charters Towers, the main difference being the more compLex suLphide mineraLogy of the Ravenswood ores. MineraLisation occurred mostLy in singLe or multipLe auriferous quartz-suLphide bodies, up to 1 m wide, fi LLing fissures in the tonaLite. At Ravenswood, the lode

...

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. - - - - MICROGRAi'~~':";S ~UREAU

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fissures trend in ':wo princip"L . I rections. The more important and numerous lodes trend between north-northwest and north-northeast and dip east at 25-45 degi a second group trends between east and northeast and dips south. The lodes do not form a network, but rather several groups of northtrending Lodes are separated by a few eas';-trending lodes. ALthough structure can be reasonably assumed to t.,:ve been a factor in the localization of mineralisation, the structuraL relationshilJs cannot be determined because of the paucity of recorded information from the underground workings. However, the two principal lode directions paraLleL the two regional structural systems. The lodes are characterised by parallel and branching veins indicative of composite fissures as at Charters Towers. Dips decrease with depth. Some orebodies (e.g. Buck Reef) consisted of zones of altered crushed tona Lite i np regnated with auri ferous su lphi des; these may represent a separate episode of mineralisation. Although ore grades continued to at Least 200 m, few reefs were worked be low 130 m because the refractory ores proved extremely difficult to treat (see Mineralogy). Most of the smaLler mines were abandoned at the base of the oxide zone. In many of the outlying centres lodes generaLly trended north to northwest or east to east-northeast. OREBODY: ShelmaLier ShelmaLier was very similar to Buck Reef and is considered to represent a mineralised shear zone. OREBODY: Sunset Ore was in two shoots, partLy connected, partly separated by a cymoid curve in the vein pitching northeast. Both strike and dip were irregular, with branching frequent. TWO main branches were worked in the richest area. At depth, width decreased, looping was common and the ore occurred in erratically distributed patcnes. Although the go ld was apparent ly rough ly even ly di st ri buted between quartz and sulphides, recovery rate for treatment of the sulphide phase was very Low, with the resuLt that smeLting of the sulphide concentrate YieLded only about a quarter of production, the bu' being obtai ned by ama 19amation. REFERENCES: Ball L.C. , 1944 Little Grand junction and LiverpooL Lass, Ravenswood. Queensland Government Mining Journal 45 P299-3DO Cameron W.E. , 1903 Recent mini ng deve lopments on the Ravenswood go ldfi e ld. QueensLand Government Mining Journal 4 p184-188 Cla r ke D. E• , 1 971 Geology of the Ravenswood 1-miLe sheet area, Queens Land. Geological Survey of Queens land. Report 53 ConnahT.H. ,1956 Mount Wright go Ld depos i t, Ravenswood. Queens land Government Mi ni ng Journa L 57 p528-535 J ac k R. L.

, 1879

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Geology and mineraL resource s of the distric t between Charter s Towers and the coast. GeoLogi caL survey of Queensl and. pUblica tion 1 Johari S. , 1976 The geochem istrY and mineraL i zation of Mount Wright, Ravensw ood, QueensL and. 'I.Sc. thesis. James Cook Univers ity, North Queens land. unpubLi shed 1v Levings ton K.R. 1981 GeoLogi caL evoLuti, on and economi c geoLogy of the Burdeki n River region, Queens Land. Bureau Mineral Resourc es, AustraL ia. BuLleti n 208 Levings ton K.R. , 1972 Ore deposit s and mines of the charter s Towers 1 :250 000 sheet area, north Queens Land. GeoLogi caL Survey of Queensl and. Report 57 Mac laren J .M. , 1900 Ravens~,ood gold fie ld. Report on its geology and reefs. Queens land Governm ent ~li ni ng Journa l 1 P293-29 6; 2 P16-19 Mac laren J .M. , 1900 Report on the geology and reefs of the Ravensw GeoLogi caL Survey of QueensL and. pUbLica tion ood goLdfie Ld. 152 Morriso n G.W. 1987 StyLes of buLk ,tonnage goLd mineraL isation in North QueensL and. IN Herbert H.K. (ed) - Gold in Queens Land. proceed ings of one-day symposiu m, Univers ity of QueensL and, June 1984. Univers ity of QueensL and. Departm ent of GeoLogy . Papers 12(1) p34 Murray C.G. , 1986 MetaLLo geny and tectonic deveLop ment of the Tasman FoLd BeLt System in QueensL and. IN Scheibn er E.(ed) - MetaLLo geny and tectonic deveLop ment of eastern AustraL ia. ore Geo Log)l Rev i ews 1 (2-4) P315-40 0 Rands W.H. , 1898 On the goLd mines at the Fanning and Mount Success . GeoLog ical Survey of QueensL and. BuLLeti n 8 Reid J .H. , 1934 Some Ravensw ood mines. A summary . QueensL and Governm ent Mining JournaL 35 P44-45; p77-78 Surjon oJ. ,1976 PetroLo gy of ~lount Wright, Ravensw ood, north Queens land. James cook Univers ity, North Queens Land. unpubLi shed 1v

rA-

~l.Sc.

thesis.

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DEPOSIT:

PAJ INGO

23

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: Au , Ag , MINES: pajingo, Scott , OREBODIES: Janet

I

A' , Janet 'B' , Mount Ross , orchid, Paj ingo , scott ,

GROUP: permo-Carboni ferous Igneous Group COMMENTS: IIlC ludes regiona l setting of Devono-Carboni ferous Basins, Drummond Basin, and permo-Carboni ferous igneous group. LOCATION: LATITUDE: 20 46 250K SHEET: SF55 2

LONGITUDE: 14626 100K SHEET: 8156

ADMINISTRATIVE SUBDIV ISION: MINING DIsncT: Charters Towers mNING FIELD: charte rs Towers LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD Geochemistry Dri lling Geo logy Geop hys i cs

DISCOVERY YEAR 1982 1982 1982 1982 OPERATING STATUS AT 1987 mNE Paj i ngo Scott

STATUS Operati ng Ope rat, ng

MINING ~lETHOD Open-Cut open-Cut

COMPANIES: OREBODY: paj i ngo PRESENT OPERATORS: Pajingo Gold Mine Pty Ltd •

...._ _r...-

COM~IENTS

....

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BUREAU--------------------..

FIJIllIIIIIIII--MICROGRAPHICS

PRESENT OWNERS: EQUITY Battle Mountain CAustralia) Incorporated. 100.00

r.

COMMENTS An ASE listed company.

PRODUC nON: MAIN PRODUCTION PERIODS: - , 1987- , RESOURCES: DATE

ORE CI 000t)

GRADECg/t)

GOLDCkg)

CLASSIFICATION

Dec 1987

1,290

8.8

11,352

Economi c Demons trated Recove rab le

0

le

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fold Belt PROVINCE: Devono-Carboni ferous Basins SUB-PROVINCE: Drummond Basin HOST ROCKS: Star Of Hope Formation Tuff, tuffaceous sandstone, volcanolithic sandstone, conglomerate. Mineralisation is in transgressive gold-quartz veins within felsic volcanies volcanogenic rocks.

and

AGE: pa laeozoic Early Carboni ferous STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY MAJOR: VolcanismCFelsic) , DEPOSIT CHARACTERISTICS: TYPES: Auriferous quartz veins in metasediments adjacent to felsic/intermediate porphyry intrusive. STYLE: Discordant, Stratabound , AGE OF MINERALISATION: palaeozoic Early permian

..

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AGE OF MINERALISA nON: pa Laeo zoi c La te Ca rbonife rous DIMENS IONS: OREBODY: Janet 'A' STRIKE LENGTH

( m

AVE

MIN

MAX 2300.0

NATURE OF MINERALISATION: Disseminated, Free Milling, PRIMARY ORE: Vein (Reef) , MINERALOGY: GEOLOGICAL SETTING OF MINERALISATION: OREBODY: paj i nJo REGIONAL SETTING: DEVONO-CARBONIFEROUS BASINS The LoLworth-Ravenswood BLock was consoLidated with the empLacement of 3 granite bathoLiths in the Late siLurian to MiddLe Devonian and aLthough not finaLLy stabi Lised ti LL the Permian, the bLock remained a Land nucleus trending east-west across the course of the Tasman FoLd BeLt. From the MiddLe Devonian, sedimentation began in severaL basins which formed over the northeastern and southern margins of the LoLworthRavenswood structura L high. The Burdekin Basin deveLoped as a west-trending ovaL depression to the northeast of the granitic/metamorphic LoLworth-Ravenswood basement. The basin opened eastwards to the sea. Ranging in tectonic activity between a mi LdLy unstabLe she Lf and a yoked intracratonic basin, it presented an aLternation of marine and continentaL conditions as it graduaLLY expanded northwards. south of the LoLworth-Ravenswood BLock, a miogeosyncLine formed in the MiddLe Devonian. In the MiddLe Devonian Tabberabberan Orogeny, a geanticLine rose in the geosyndinaL beLt, and the intermontane Drummond Basin formed on its western side. Both basins were destroyed by the MiddLe Carboniferous KanimbLan Orogeny and from Late Carboni ferous-EarLy Permian were dominated by igneous acitivty of the north QueensLand permo-Carboniferous vol,canic/pLutonic p rovi nce. ASSOCIATED MINERALISATION . The main goLd mineraLisation in the basins is associated with feLsic voLcanic/subvoLcanic centres empLaced into the basin succession during permo-carboni ferous igneous activity goLd-quartz veins at Far Fanning, Argentina, picadilLy and GoLden VaLLey, and breccias at Mount Success in the Burdekin Basin; and veins at pajinljo and Mount CooLon in the Drummond Basin. (PermoCarboni ferous ,gneous-associated mi nera Li sation a Lso occurs in basement rocks of the Drummond Basin - WirraLie and Mount Wyatt in the Anakie InLier). GEOLOGICAL SETTING: PAJINGO pa~if,go occurs in a suite of feLsic voLcanic and voLcanoLithic rocks La,d Clown in the Drummond Basin. The Drummond Basin deveLoped after the Tabberabberan Orogeny in the Late Devonian as a broad downwarp aLong the southern flank of the LoLworth-Ravenswood BLock, a structuraL remnant of a Largeintermontane basin. The basin succession accumuLated through 3 cycLes of continentaL sedimentation separated by periods of upLift and ~,i desp read vo Lcani sm. The basin sequence was foLded during the KanimbLan Orogeny in the MiddLe carboniferous. FoLds in the deposit area are ol'en and shaLLowLy dipping. The host formation to the mineraLisation is a 12 000 m thick continental suite of extrusive fe Lsic to intermediate voLcanics and fluviaL

. . . ._ ~

*** InIIBI

N1 0

,~*,~ - ~ ...

AGPS--...

pIIIlI--MICROGRAPHICS BUREAU ~---~--~----------. .... Eediments marking the start of the third crcLe of sedimentation. The suite consists of LapiLLi tuff, weLded tuff, tuffaceous sandstone, voLcanoLithic sandstone, quartz pebbLe sandstone and congLomerate. MineraLisation occurs in eplthermaL styLe quartz veins. REFERENC ES: LevingstonK.R. ,1981 GeoLogicaL evoLution and economic geoLogy of the Burdekin River region, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 208

oLgers F. , 1972

GeoLogy of the Drummond Basin, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 132

Porter R. , 1986 Paj ingo goLd property - the discovery and geoLogicaL introduction. IN Go Ld e xp lo rati on and deve Lopment, no rth Queens Land. AusIMM Conference, Charter~ Towers, August 1986. Extended abstracts. AusIMM. North QueensLand Branch 1v p9-12

000000000000000000000 0000000000000000000

,b~*

A11 ***

-AGPS---'"

fIIIIIIIISl--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - - . DEPOSIT:

24

DITTMER

DEPOSIT IDENTIFICATION:

----------------------

PRINCIPAL COMMODITIES: Au , Ag , Cu , MINES: Dittmer , OREBODIES: Dittmer , Duffer, GROUP: C~etaceous COMMENTS: See Deposit No.

Igneous Group 35 Gympie for regionaL setting of New EngLand FoLd BeLt.

LOCATION: LONGITUDE: 148 24 100K SHEET: 8557

LATITUDE: 20 27 250K SHEET: SF55 3 ADMINISTRATIVE SUBDIV ISION: MINING DISTICT: Bowen MINING FIELD: LOCALITY: DEVELOPMENT HISTORY:

-------------------DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1935 OPERATING STATUS AT 1987 MINE Dittmer Dittmer

MINING t~ETHOD unde rg round unde rg round

STATUS Comp Leted HistoricaL

COMPANIES: OREBODY: Dittmer PRESENT OWNERS: Southwest GoLdmines N

EQUITY 100.00

L.

r.

COMMENTS FormerLy Buddha GoLd

Mines

N L.

PRODUCTION:

III.-

~

***

B11

***

_ = : I_ _~

I[ji]\-AGPS - _..

.---MICROGRAPHIeS

BUREAU----~--_a.------~---~-·

CUMULATIVE PRODUCTION (TO DEC .1986): ORE(t): GOLD(kg) RECOVERED GRADE(g/t) 67,406 1,950 28.92

COMMENT~

MAIN PRODUCTION PERIODS: 1935-1951 , 1967-1971 , 1982-1984 , RESOURCES: PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: Tasman Fo ld Be lt PROV INCE: New Eng Land Orogen SUB-PROV INCE: strathmui I" SYnc line HOST ROCKS: carmi la Beds Massive dacitic and andesitic pyrocLastics and subordinate lavas; bedded pyroc lastics and labi le sediments. Mineralisation was in quartz-suLphide vein in andesite flows and breccias at granite contact. Hectate Granite Granodiorite and adameLLite, late stage leucocratic phases; apLitic microgranite. Intrudes mineralised voLcanics. ?GeneticalLy reLated to mineraLisation. AGE: Palaeozoic Early permian STRUCTURAL FEATURES MAJOR: Shearing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, IGNEOUS PROXIMITY MAJOR: plutonism(Granodiorite) , VolcanismOntermediate) , AGE OF INTRUSION: Mesozoic Early Cretaceous ALTERA TION: Mineralisation is associated with hydrothermal alteration of country rock. Andesite is si licified, epidotised, and pyritised. DEPOSIT CHARACTERISTICS:

....

***

c11

*** ...._ - - . - - \ t i i ] j - A G P S - -..

. - - - MICROGRAPHIes BUREAU - - - - - - - - - - - - - - - - - - - - - . TYPES: Auriferous quartz veins in intermediate volcanics adjacent to granitoid. sTYLE: Discordant, Stratabound , AGE OF MINERALISATION: Mesozoic Early Cretaceous DIMENS IONS: OREBODY: Duffer STRIKE LENGTH TRUE WIDTH DOWN-DIP DEPTH

m) cm ) m)

MIN 275.0

150.0

AVE

13.0

MAX 500.0

180.0

NATURE OF MINERALISATION: primary, PRU1ARY ORE: Vein (Reef) , MINERALOGY: OREBODY: Dittmer Sulphide ore: gold, pyrite, chalcopyrite, subordinate sphalerite, galena, bournonite, trace pyrrhotite. Tne pyrite has been partly replaced by the base metal sulphides, and fractured crystals of pyrite contain thin zones which have been recemented by quartz and later su lphi des. Most of the chalcopyrite was introduced later, and tends to be aligned parallel to the PYrite fracture planes. Most of the gold occurs as fine grains within pyrite. Gold content increases with chalcopyrite, galena, bournonite abundance. Coarse gold may be associated with the latter two sulphide minerals. some of the gold was introduced with pyrite, some post-dates pyrite fracturing. Gangue: quartz, calcite, siderite. GENETIC MODELS: Mineralisation was presumably introduced by the Hectate Granite. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Dittmer Dittmer lies on the western margin of the Strathmuir Synclinorium at its contact with granitic rocks of the Connors Arch. The deposit was in a quartz reef in andesitic volcanics in the lower part of the Synclinorium sequence. REGIONAL SETTING: STRATHMUIR SYNC LINE The Synclinorium contains continental felsic volcanics and volcaniclastic freshwater sediments which were deposited on a shallow shelf on the seaward side of a volcanic arc. The arc (Camboon Volcanic Arc - see Deposits No. 35 Gympie and 32 Cracow) developed in the Early permian over the site of the pre-existing Carboni ferous Connors-Auburn Arc. Thick andesitic volcanics were extruded along the western side of the arc. East of the arc a deep marine trough developed in the south but in the north the arc was flanked by an emergent shelf, and volcanism extended across to the eastern side of the arc. In the Late permian the shelf Sequence was folded into a broad, southeast-plunging synclinal structure, the Strathmuir Synclinorium, with local, tight, small-scale foLds. The volcanogenic sequence=Carmi la Beds. The deposit region was the site of major granite intrusion in the Early cretaceous, when renewed caLc-alkaline volcanic/plutonic activity

,~**

011 ***

....--MICROGRAPHICS

BUREAU-------------------..

affected the New EngLand FoLd Belt, concentrated in the northern part (see Deposit No. 35 Gympie), The Carboniferous Urannah Igneous compLex (which makes up the Connors Arch in the deposit region) and the CarmiLa Beds were intruded by a Lar!;je mesozonaL adameLLite-granodiorite bathoLith, the Hectate Gramte. The Carmi La Beds aloe LocaLLy intruded by granitoid bosses of probabLe Hectate Granite affi Liation. The Carmi La Beds consist of up to 7500 m of massive dacitic and andesitic pyrocLastics and subordinate Lavas, bedded pyrocLastics, congLomerate, incLuding voLcanic congLomerate, lithic Labi Le and tuffaceous sandstone, si Ltstone and shaLe. The sequence dips uniformLy east-northeast at 30-40 deg. The CarmiLa Beds are thought to overLie Devono-Carboniferous basement rocks of the Connors Arch and Campwyn BLock unconformabLy. The Hectate Granite comprises biotite-hornbLende granodiorite, biotite adameLLite, apLitic microgranite, and diorite. The Late stage phases are associated with Large shear zones. The contact zone is marked by strong hornfeLsing. The consistent dip of the Carmi La Beds away from the granite sUi,lgests that empLacement was mainLy by doming of cover rocks, with minimaL assimi Lation, and that the present base of the Carmi La Beds corresponds roughLy with the originaL depositionaL base. GEOLOGICAL SETTING: DITTMER The main orebody at Dittmer was the Duffer vein. The vein occurs in a shear zone in a host sequence of aLtered andesite with subordinate andesite and dacite breccia, and occurs cLose to a diorite boss, which is possibLy a contaminated cu,:;oLa of the Hectate Granite. The main contact with the Hectate Granite is Less than 1 km distant from the ~~~~;i~~in mineraLisation occurs within or adjacent to Hectate Granite at Normanby, Mount Hector and Ma rengo. ALLuviaL pLacer deposits derived from primary veins in a simiLar environment to Dittmer (andesite host adjacent to granite contact) occur at Mount Britton on the western side of the Connors Arch. REFERENCES: Paine A.G.L. , CLarke D.E. ,Gregory C.M. 6 1974 GeoLogy of northern haLf of tne Bowen 1 :250 0 0 Sheet area, QueensLand (with additions to the geoLogy of the southern haLf). Bureau MineraL Resources, AustraLia. Report 145 0000000000000000000000000000000000000000

...

,~**

E11

*,~,~

-----I---------------.~-AGPS---

..

....--MICROGRAPHICS DEPOSIT:

25

BUREAU-------------------....

WIRRALlE

DEPOSIT IDENTIFICATION:

----------------------

PRINCIPAL COMMODITIES: AU , Ag , MINES: WirraLie , OREBODIES: WirraLie , WirraLie West, GROUP: permo-Carboni fe rous Igneous Group COMMENTS: mc Ludes regionaL setting of Anakie Inlier. See Deposit No. regionaL setting of Permo-Carboniferous igneous group.

23 Pai ingo for

LOCATION: LONGITUDE: 1473 100K SHEET: 8355

LA TITUDE: 21 10 250K SHEET: SF55 7 ADMINISTRATIVE SUBDIVISION: MINING DISTICT: CLermont MINING FIELD: LOCALITY: DEV ELOPMENT HISTORY:

DISCOVERY METHOD Geochemistry DriLling GeoLogy Geophys i cs

DISCOVERY YEAR 1986 1986 1986 1986 OPERATING STATUS AT 1987 MINE WirraLie

STATUS Operating

MINING METHOD oPen-Cut

CO~lPANIES:

OREBODY: WirraLie COMMENTS

PRESENT OPERATORS: AustraLian ConsoLidated MineraLs Ltd. EQUITY

PRESENT OWNERS:

.....

~

~

COMMENTS

-~----_-----IWiill-AGPS

-_l1li

.---MICROGRAPHICS

.......

BUREAU-----------~------

Australian Consolidated MineraLs Ltd.

100.00

PRODUCTION: MAIN PRODUCTION PERIODS: - , 1988- , RESOURCES: DATE

ORE('OOOt)

GRADE(9/t)

GOLDCkg)

CLASS IFlCA nON

DeC 1 987

3,650

2.8

10,037

Economic Demonstrated RecoverabLe - Measured

olc

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROVINCE: BLOCK: Tasman FoLd Be It PROVINCE: Thomson Orogen SUB-PROVINCE: Anakie InLier HOST ROCKS: Uka Lunda Beds Lithic sandstone, shaLe, phyllite, limestone, congLomerate. Granite, granodiorite, ap Lite, microgranite. AGE: pa Laeozoi c Mi dd le Devoni an STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, IGNEOUS PROXIMITY MAJOR: pLutonismCGranite) , AGE OF INTRUSION: paLaeozoic Lute Carboniferous METAMORPHIS M: The Ukalunda Beds have been mi ldLy regionally metamorphosed. DEPOSIT CHARACTERISTICS:

-----------------------TYPES: Auri fe rous quartz veins in metasediments adj acent to fe Ls i c li nte rmedi ate

***

G11 i"b\

-AGPS--....

...- - MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - - . porphyry intrusive. STYLE: Discordant, AGE OF MINERALISATION: paLaeozoic Late Carboniferous DIMENS IONS: NATURE OF MINERALISATION: MINERALOGY: GEOLOGICAL SETTING OF MINERALISATION: OREBODY: WirraLie WirraLie Lies in the northern part of the Anakie InLier. MineraLisation is associated with Carboniferous granitoids which intrude Devonian metasediments and metavoLcanics. The inLier comprises a discontinuous north-trending bLock of earLy to mid PaLaeozoic foLded and metamorphosed mafic voLcanics and sediments, the Lower units of which may be correLative with the metamorphosed voLcano-sedimentary sequence (Cape River Beds and equivaLents) of the LoLworth-Ravenswood BLock. The northern part of the inLier comprises foLded MiddLe Devonian sediments - Lithic sandstone, shaLe, phyLLite, Limestone, congLomerate - of the UkaLunda Beds. The southern part of the inLier comprises ?Cambrian-Ordovician muLtipLy deformed and regionaLLy metamorphosed (to greenschist facies) voLcanics and sediments - the Anakie Metamorphics. The metamorphic rocks comprise a basaL mafic voLcanic unit over Lain a metasedimentary unit of micaceous quartzite, quartzose arenite, mica schist, phyLLite and sLate. The basement rocks exposed in the inlier probabLy existed as a shallow submerged pLatform or Low Land mass near the eastern margin of the Drummond Basin during deposition of the first sedimentary cycLe in the Late Devonian. The present structuraL form of the inLier was reinforced by foLding during deformation of the basin in the MiddLe Carboniferous. The northern part of the inLier has been extensiveLy intruded by a series of Large granitoid p Lutons eLongate on a coLLinear northeast axi s. The inLier i~ onLapped by Late Devonian sediments and voLcanics of the Drummond Bas,n. REFERENCES: Day R.14. , Whitaker W.G. , Murray C.G. , Wi Lson I.H. , Grimes K.G. 1983 QueensLand GeoLogy. A companion voLume to the 1:2 500 000 scaLe geoLogicaL map (1975). GeoLogicaL Survey of QueensLand. pubLication 383 MaLone E.J. , Corbett D.W.P. t. Jensen A.R. , 1964 GeoLogy of the Mount cooLon 1 :2:>0 000 Sheet area. Bureau MineraL Resources, AustraLia. Report

64

OLgersF. ,1972 GeoLogy of the Drummond Basin, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin

...

----------------------~-AGPS

-_..

VJIIIIII--MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - -.... 132 0000000000000000000000000000000000000000

..

---------~----------[Ji]]-AGPS---

..

.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - -...- - - - -....

DEPOSIT:

26

MOUNT CDDLON

DEPOSIT IDENTIFICATION:

PRINCIPAL COMMODITIES: AU , Ag , MINES: Mount Coo Lon , OREBODIES: KoaLa, Mount CooLon , GROUP: permo-Carboniferous Igneous Group CO~lMENTS : See Deposit No. 23 paj ingo for regionaL setting of Devono-Carboni ferous Basins, Drummond Basin, and permo-Carboniferous igneous group.

LOCATION: LATITUDE: 21 22 250K SHEET: SF55 7

LONGITUDE: 147 21 100K SHEET: 8355

ADMINISTRATIVE SUBDIVISION: MINING DIS TIC T: CLe rmont MINING FIELD: Anakie LO,:A).lTY: DEVELOPMENT HISTORY: DISCOVERY METHOD Prospecting

DISCOVERY YEAR 1913 OPERATING STATUS AT 1987 MINE Mount Coo Lon

STATUS Hi stori ca L

MINING METHOD Underground

COMPANIES: OREBODY: Mount Coo lon COMMENTS

PRESENT OPERATORS: Renison GoLdfieLds ConsoLidated. PRESENT OWNERS: Renison GoldfieLds ConsoLidated.

....

EQUITY 100.00

r.

CO~lMENTS

,~**

J 11

*1dt

g§]]-AGPS ........-...

....--MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - . PRODUC TION: CUMULATIVE PRODUCTION CTO DEC.1986): ORECt): 284,854

GOLDCkg) 4,395

RECOVERED GRADECg/t) 15.42

COMMENTS

MAIN PRODUCTION PERIODS: C1914-1931>, 1931-1934, C1934-1939) , RESOURC ES: DATE

OREC'OOOt)

Dec 1987

500

GRADECg/t)

GOLDCkg)

CLASSIFICATION

10.0

5,000

sub-Economic Inferred In-situ

o/c

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fo ld Be lt PROV INCE: Devono-Carboni fe rous Basi ns SUB-PROVINCE: Drummond Basin HOST ROCKS: Silver Hills Volcamcs RhyoLite, welded tuff, andesite, agglomerate, sandstone, mudstone. MineraLisation was contained in fissure adjacent to a shear zone andesite unit within feLsic voLcanic sequence.

in

Quartz diorite. Intrudes voLcanic sequence adjacent to mineraLisation. mineraLisation.

reLated

?GeneticaLLy

altered to

AGE: pa Laeo zoi c Late Devoni an STRUCTURAL FEATURES MAJOR: Shearing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, IGNEO, IS PROXIMITY MAJOR: plutonismCGranodiorite) , VoLcanismCIntermediate) , AGE OF INTRUSION: paLaeozoic Late Carboniferous ALTERATION: Mineralisation is associated with strong but Localised pyritisation and silicification. sediments in contact with granite on its

-AGPS--'"

.....- - MICROGRAPHieS BUREAU---------------~--__. southwestern margin are aLtered to magnetite-bearing garnetiferous rock. The mineraLised andesite, which is in contact with the granite on its northeastern margin, is si Licified, pyritised and aLtered to magneti te-beari ng epidote-garnet roc k. DEPOSIT CHARACTERISTICS: TYPES: Lode in intermediate voLcanics adj acent to fe Lsic/intermediate porphyry intrusive. STYLE: Discordant , Stratabound , MORPHOLOGY: LenticuLar, AGE OF MINERALISATION: paLaeozoic Late Carboniferous DIMENS IONS: OREBODY: Mount CooLon STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION

m )

cm )

m )

MIN

AVE

90.0

200.0

m)

~lAX

500.0 750.0 140.0 30.0

NATURE OF MINERALISATION: Disseminated, Oxidised, primary, PRIMARY ORE: Lode (ALterat~on Zone) , MINERALOGY: OREBODY: Mount cooLon suLphide ore: pyrite, rare pyrrhotite. GoLd was mostLy Locked in pyrite. Some ore = goLd in quartz + aduLaria. Gangue: quartz (chert), chLorite, andradite, epidote, hematite, zeoLite, caLcite, biotite, sericite, sti Lbite. GENETIC CONTROLS: ControLs are structuraL - ore is associated with a shear/fissure zone and LithoLogicaL - ore is associated with aLtered andesite within feLsic voLcanics which were evidentLy preferentiaLLy susceptibLe to hydrothermaL aLteration. GENETIC MODELS: The source of the si Licification and mineraLisation is considered to be a smaLL subsurface paraLLeL eLongate cupoLa of the intruding quartz diorite. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Mount CooLon REGIONAL SETTING: DRUMMOND BASIN Mount CooLon occurs in the northeastern part of the Drummond Basin in a narrow subbasin separated from the main part of the basin to the west by the Anakie InLier (See Deposit No. 25 WirraLie). The northern part of the inLier, adjacent to the deposit region, comprises foLded MiddLe Devonian sediments - Lithic sandstone, shaLe, phyLLite, Limestone, congLomerate - of the UkaLunda Beds. The basin sequence in the deposit region contains marine and continentaL

*,~*

L11 ***

-

-AGPS--....

. - - - MICROGRAPHIeS

BUREAU---------I---------.......

sediments of the basaL basin unit the Mount Wyatt Formation and terrestriaL feLsic voLcanics, the si Lver Hi LLs VoLcanics, which were in part deposited directLy onto basement. The SiLver HiLLs VoLcanics marked the end of the first sedimentary cycle. The basin sequence is extensive Ly intrudeCl and overLain by Late Carboni ferous igneous rocks. The basin sequence is intruded by smaLL granitoid stocks and terminated on its eastern margin by an extensive block of Late Carboni ferous fe Lsic voLcanics, the 8ungonanna VoLcanics. GEOLOGICAL SETTING: MOUNT COOLON Mount CooLon is hosted by fe Lsic voLcanics which in the deposit area overLie isoLated outcrops of UkaLunda Beds and are intruded by Late Carboniferous quartz-diorite stocks. The host voLcanics were assigned to the Mount Rankin Formation (third sedimentary cycLe) by MaLone & others (1964), but OLgers (1972) re-assigned them to the silver HilLs VoLcanics. Tne Latter formation comprises up to 1500 m of spheruLitic and flow-banded rhyoLite and fe Lsic weLded tuff with subordinate andesite, aQgLomerate, tuff and minor sediments. MineraLisatlon was contained in a singLe Lode system in an isoLated, 800 m-wide beLt of andesite within feLsic voLcanics. The voLcanic(-sedimentary) sequence is intruded by an eLongate, 3 kmwide body of quartz-diorite. The orebody consisted of si Liceous rock (= chaLcedonised, pyritised andesite) adjacent to a shear in the andesite 300 m from the Qranite contact. The Lode fissure is transected but not sheared or dlspLaced by a compLex ~oint system, but branches at its southern end. The weathered zone was hlghLy enriched. REFERENC ES: Cameron W.E. , 1914 GoLd deposits at Mount Coolon, Clermont district. Queens land Government Mi ni ng Journa l 15 P461-462 Cameron W.E. , 1915 Mount coolon gold field. Queens land Government Mi ni ng Journa l 16 P447-448 coldham J.C. , 1953 Mount Coolon gold mine. IN Edwards A.8.(ed) - Geology of Australian ore deposits. 5th Empire Mining & Metallurgical Congress, AustraLia & New Zea land, 1953, Me lbourne. AUS IMM 1v p807-812 Jensen H.I. , 1921 Geology of Mount Coolon and district. Queens land Government Mi ning Journa l 22 P491-495; 23 p7-11 Malone E.J. , Corbett O.W.P. e. Jensen I\.R. , 1964 Geology of the Mount Coolon 1:2~0 000 Sh~et arp.a. 8ureau MineraL Resources, AustraLia. Repo~~ 64 Morton C.C. , 1922 Mount Coolon goLdfieLd.

***

M11

***

m..---------------------!MiID-AGPS----

....--MICROGRAPHICS

BURBAU---------------,-------.

Queens Land Government Mi ni ng Journa L 23 P425-430 Morton C.C. , 1935 The Mount Coo Lon go Ldfi e ld. Queens Land Government Mi ni ng Journa L 36 P196-200;P232-237 OLgers F. , 1972 GeoLogy of the Drummond Basin, Queens Land. Bureau MineraL Resources, AustraLia. BuLLetin 132 StiLlweLL F.L. , 1936 Various mineragraphic reports 1931-1936. CSIRO. Mineragraphic Report 17; 24; 27; 29; 30; 32; 45; 64; 98; 99 0000000000000000000000000000000000000000

*** N11

,~**

...

-AGPS--..a

..----MICROGRAPHICS B U R E A U - - - - - - - - - - - - - -....- - - - - - ·

DEPOSIT:

CLERMONT

27

DEPOSIT IDENTIFICATION:

---------------------SYNONYMS: Peak Downs,

PRINCIPAL COMMODITIES: AU , MINES: Black Ridge, clermont , Goldfinger , MicLere , OREBODIES: Blac k Johnsons , Blac k Ri dge , Cement Hi LL Mcmaste rs , Mi c le re ,

,

C le rmon t

Goldfinger

,

GROUP: Bowen Group COMMENTS: See Deposit No.

32 Cracow for regional setting of Sowen Ba"in.

LOCATION: LATITUDE: 22 39 250K SHEET: SF55 11

LONG ITUDE: 147 35 100K SHEET: 8452

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: clermont MINING FIELD: LOCALITY: DEVELOPMENT HISTORY:

-------------------DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1861 OPERATING STATUS AT 1987 MINE Cle rmont Go\.dfi nge r Black R,dge Cle rmont Miclere

STATUS Histor'cal possible Historical Hi stori ca l Hi stori ca l

MINING ~lETHOD Unde rg rou nd Open-Cut Alluvi a l Alluvi a l ALLuvial

COMPANIES· OREBODY: Black Ridge PRESENT OPERATORS:

....

COMMENTS

*** A12

l~**

...

~-AGPJ---

..----MICROGRAPHICS

BUREAU---------------------....

Deni son Resources N L. PRESENT OWNERS: EQUITY :t, china GeoLogy Import 8. Export Corporation 50.00 Denison Resources N L. 50.00

COMMENTS

OREBODY: Go Ldfi nger COMMENTS

PRESENT OPERATORS: Noranda Pad fi c Ltd EQUITY :t, 40.00 60.00

PRESENT OWNERS: KoLmar Resources N L. Noranda Pad fic Ltd

COMMENTS

PRODUC TION: CUMULATIVE PRODUCTION (TO DEC.1986): ORECt):

GOLDCkg) 8,200

RECOVERED GRADEC9/t) 0.00

COMMENTS Ore tonnages and recovered grade not appLicabLe to aLLuviaL deposits. Zero figures resuLt from program ca LcuLations.

MAIN PRODJCTION PERIODS: 1862-1901 , 1931-1956 , RESOURCeS: PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: PROV INCE: SUB-PROVINCE: Bowen Basin HOST ROCKS: BLair AthoL CoaL Measures Quartz J)ebbLe congLomerate, coaL, carbonaceous mudstone, shaL~. MineraLisation consisted of deep Lead CpLacer) deposits in basaL cong Lomerate.

quartz-pebbLe

Anakie Metamorphics Metamorphosed mafic voLcanics, mica schist and quartzite, sandstone, phyLLite, sLate. Host to minor vein mineraLisation. ?Source of pLacer and aLLuviaL deposits. AGE: pa Laeozoi c Early permian

-.-

- - - - - - R i J ] - A G P S - -..

.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - -...- - -.... STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGN£OUS pROXIMITY METAMORPHISM: RegionaL metamorphic grade of basement (Anakie InLier) is greenschist facies. Host basin sediments are unmetamorphosed. ALTERATION: DEPOSIT CHARACTERISTICS: TYPES: Deep Lead/P Lacer. ALluv i aL. STYLE: conformabLe , Di scordant , AGE OF MINERALISATION: Cainozoic Recent QuaternarY AGE OF MINERALISATION: Cainozoic TertiarY AGE OF MINERALISATION: paLdeozoic Early Permian DIMENS IONS: NATURE OF MINERALISATION: Free MilLing, pRIMARY ORE: Vein (Reef) , SECONDARY ORE: Deep Lead, DetritaL (ALLuviaL) , MINERALOGY: OREBODY: CLermont GoLd, iLmenite, zircon, cassit(!rite, tourmaLine, corundum, tantaLitecoLymbite. Gold was r:naracterised oy high fineness (= high Au:Ag ratlo) and coarse gralnsl ze. GENETIC CONTROLS: GENETIC MODELS: The pLacer goLd was IJresumabLy derived from auriferous quartz reefs in the Anakie Metamorphics{ aLthough these are mostLy barren (Veevers & others, 1964). I'ons 0983) has interpreted the pLacer mineraLisation as end moraine gLaciaL deposits deposited at the northern extremity of the permian ice sheet. The pebbLe congLomerate is interpreted as a terrestriaL moraine ti LL. According to the modeL, primary reef deposits were first enriched by oxidation and subsequentLy eroded, transported and concentrated by gLacial ~nd eLuviaL action. The model is supported by the high degree of cLast rounding indicative of Long transport, the occurrence of striations, and some LithoLog;caL features of the conglomerate indicative of a glacial tilL.

.....__

~

*** C12

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~-AGPS--

...--MICROGRAPHICS BUREAU ~

IIBfoB

---------""

GEOLOGICAL SETTING OF MINERALISATION: OREBODY: clermont clermont is a large placer deposit at the western margin of the Bowen Basin adj acent to basement rocks of the southern part of the Anakie Inlier. In the deposit region the inlier consists of the Anakie MetamorphlcS (See Deposit No. 25 Wi rralie). south of clermont the metamorphics are intruded by a large Late oevonian Batholith, the Retreat Granite, making up much of the exposed southern portion of the inlier. The metamorphlcs and granite are overlain by isolated sections of volcanics assigned to Silver HilLs Volcanics. The Bowen Basin sequence at Clermont consists of up to 240 m of co~tinental (fluvial) sediments - the Blair Athol Coal Measures conRisting of coal, carbonaceous mudstone and shale overlYing a basal quartz-pebble conglomerate. The conglomerate rests unconformably on Anakie Metamorphics. The sediemnts were deposited in a restricted envir o tll11ent in a smaLL intracratonic basin formed over the basement inLier during Early Permian regression. Much of the northern part of the basin east of Clermont is covered by an extensive, northerly-trending Tertiary flood basaLt province. The plateau basalts were associated with oligocence orogenesis and uplift of land region to the east. 60ld mineralisation in the Clermont district occurs principally in deep leads in the basal quartz-pebble conglomerate of the basin sediments; mi,'or mineralisation occurred in quartz reefs of the Anakie Metamorphics, in ?Tertiary alluvial deposits beneath the TertiarY basalt, and in Recent alluvial deposits. The host rock to the deep leads is a poorlY sorted polymictic clastsupported conglomerate restin~ either directly on mica schist of the Anakie Metamorphics or on sedlments consisting of conglomerate, sandstone and siltstone. con~lomerate clast Lithologles present in varying proportions are chlorltic schist, sandstone, quartzite, granite, various volcanic rocks, vein quartz and a quartz-tourmaline rock that appears to be a hydrotnermal replacement of a well-foliated schist. Most are less than 30 cm diameter. Gold occurred mainly in the conglomerate cement, rare ly in the boulders. Gold content was posltively related to the concentration of granite and quartz-tourmaline clasts. Distribution of the gold in the leads was patchY, but was ap!?arently controlled by smalL faults and quartz veins in the bedrock, which although barren formed resistant bars across the watercourses and acted as riffles. REFERENCES: Dimmick T.O. , 1951 Mi c le re fi e ld, Cle rmont. QUeensland Govertll11ent Mining Journal LII (602) P953-955 Dunstan B. , 1902 The Clermont gold field. Parts 1 and II· Queensland Government Mining Journal

3 p404-410i P459-468

Dunstan B. , 1902 The Cle rmont go ld fi e ld. Geological Survey of Queensland. 176

publication

__________________

~

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...

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....--MICROGRAPHICS BUREAU ----~_-..---~ ....- -...-

...-~--..

East J.D. , 1946 Mi cle re fi e ld, C le rmont. Queensland Government Mining Journal 47 P274-275 East J .0. f 1947 Mic lere fie ld, C lermont. Queensland Government Mining Journal 48 P17-19; p296-298; p195-197 East J.D. 1948 Mi cle re fi e{d, C le rmont. QUeens land Government Mi ni ng Journa l 49 P14-17; p283-285 East J .0. , 1949 Mi cle re fi e ld, C le rmont. Queenaland Government Mining Journal 50 P90-92; p346-348; p713-716 East J.D. , 1950 Mi c le re fi e ld, C le rmont. Queensland Government Mining Journal 51 P635-637; p84 7-848 I'on~ M.E. , 1983 Some aspects of the Cle rmont go ldfi e ld. IN Permi an geo logy of QUeens land. proceedings of symposium, Brisbane, July 1982. Geological society of Australia. Queensland Division 1v p379-383

Kay J. R. , 1 983 Queensland. IN Permian geology of Queensland. proceedings of symposium, e ri sbane, JU ly 1982. Geological society of Australia. Queensland Division 1v p343-352

A review of metalliferous mineralisation associated with permian rocks in

Marton C.C. , 1934 Mic lere diggings, C lermont district. Queensland Government Mining Journal 35 P225-230 Marton C.C. , 1936 eedford's reef, C lermont district. Queensland Government Mining Journal 37 P198-201 ReidJ.H. ,1936 Mi cle re fi e ld, C le rmont. Queensland Government Mining Journal 37 P194-197 RidgwaY J .E. (1938 Notes on the M' c le re fi e ld. Queensland Government Mining Journal 39 P41-46 Ridgway J .E. , 1939 Re Mic lere, general report - deep workings, crushing s , and present water position.

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....--MICROGRAPHICS BUREAU _ _

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QueensLand Government Mining JournaL 40 P401 Ridgway J .E. , 1944 Mi c Le re a LLuv i a L goLd fi e Ld • QueensLand Government Mining JournaL 45 P331-334 Veevers J.J. , RandaL M.A. , MoLLan R.G. , Paten R.J. , 1964 The geoLogy of the cLermont 1:250 000 Sheet area, Queens Land. Bureau MineraL Resources, AustraLia. Report 66

0000000000000000000000000000000000000000

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. - . - - MICROGRAPHieS BUREAU-.s~----...._ - - - - - - - - - - . DEPOSIT:

28

MOUNT CHALMERS

DEPOSIT IDENTIFICATION:

PRINC IPAL COMMODITIES: AU , A9 , Cu , MINES: Mount Cha Lme rs , OREBODIES: Main Lode, Mount ChaLmers , 14est Lode, GROUP: Mount Morgan Group COMMENTS: Includes regionaL setting of Berserker Graben. regionaL setting of New EngLand FoLd BeLt.

See Deposit No.

35 Gympie for

LOCATION: LATITUDE: 23 18 250K SHEET: SF56 13

LONGITUDE: 150 39 100K SHEET: 9051

ADMINISTRATIVE SUBDIVISION: MIIING DISTICT: Rockhampton FIELD: LOCALITY:

M~NING

DEVELOPMENT HISTORY: DISCOVERY ~lETHOD prospecti ng Geochemistry Dri LLing GeoLogy Geophysics

DISCOVERY YEAR 1860

1977 1977 1977 1977

OPERATING STATUS AT 1987 MINE Mount ChaLmers Mount ChaLmers

STATUS HistoricaL Camp Lete d

MINING METHOD Unde rg round Open-Cut

COMPANIES: OREBODY: Mount ChaLmers PRESENT OWNERS:

EQUITY

r.

COMMENTS

***

G12 M,,~

~---------------------[i3-AGPS--"

. - - - MICROGRAPHIeS

BUREAU-------------------...... 100.00

Mount Morgan Limited. PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 1,214,396

GOLDCkg) 3,775

RECOVERED GRADECg/t) 3.10

COMMENTS

MAIN PRODUCTION PERIODS: 1908-1914 , 1941-1943 , 1979-1982 , RESOURCES:

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fo ld Be l t PROVINCE: New Eng land Orogen SUB-PROVINCE: Berserker Graben HOST ROCKS: Berserker Beds Felsic to intermediate volcanics, tuffaceous mudstone, mudstone, lithic labi le arenite, si ltstone. Mineralisation consisted of two elonllate parallel lodes each composed of an upper massive and partly bedded pyrite-barlte lens and a lower stringer sulphide zone. AGE: palaeozoic Early permian STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: stratigraphic Boundary, IGNEOUS PROXIMITY MAJOR: Volcanism(Felsic) , SIGNIFICANT: Volcanism(Intermediate) , ALTERATION: Mineralised sequence is intensely altered:i) Pervasive ?clay alteration. ii) Intense clay and sericite (above ore horizon). iii) Quartz-chlorite sericite (=ore horizon). The unit grades from pyritic sericitic tuff through sericitic rock wlth bedded sRhalerite and barite to massive bedded sulphides. (Some apparent silicification may be primary si licate deposition).

,'0'0':

H1 2

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.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - -..... iv) Intense si Licification, chLorite-sericite aLteration (footwaLL). The intensity of si Licification increases stratigraphicaLLy upwards to the top of the stringer suLphide zone. Above the sericitic horizon overLying the massive suLphides, the hanging-wall sequence is virtually unaLtered - minor carbonate veining and bLeaching. DEPOSIT CHARACTERISTICS:

-----------------------TYPES: Massive copper-goLd suLphide in feLsic voLcanics (voLcanogenic). STYLE: conformabLe , Stratabound , AGE OF MINERALISATION: paLaeo7-oic EarLy permian DIMENSIONS: OREBODY: Main Lode

MIN

TRUE WIDTH STRIKE LENGTH VERTICAL DEPTH OREBODY: West Lode

m m m

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OF COVER

m m m m

AVE

100.0 20.0 MIN

AVE

40.0

~IAX

130.0 500.0 60.0 MAX

250.0 90.0 45.0

10.0

NATURE OF MINERALISATION: Massive , MINERALOGY: OREBODY: Mount Cha Lme rs stringer zone: goLd, si Lver in chaLcopyrite, pyrite, chlorite, quartz stn nQers. DoLom1te-pyrite horizon: doLomite, caLcite, pyrite (upper zone); doLomite, taLc, cLay (lower zone). Massive suLphide zone: pyrite, chaLcopyrite, sphaLerite, gaLena. Gangue: carbonate, barite. Meta L distribution is zoned: pb, zn accompany AU, A9 in the massive suLphide zone but are absent in the stringer zone. GoLd is concentrated in the centraL portions of the Lode structure within the massive suLfide ore and the upper LeveLs of the stringer zone. chaLcopyrite occurs with the goLd and extends LateraLLy in the massive ore ana at depth in the stringer zone. sphaLerite ana gaLena are concentrated in the edges of the massive ore and within the doLomite-pyrite facies downs Lope from the copper-goLd zone. GENETIC CONTROLS: ControLs are mainLy LithoLogicaL - mineraLisation occurs in fine-grained tuffaceous uni t between fragmenta L pyrocLasti cs. FLuid incLusion data (Large & Both, 1980) indicate homogenisation temperature range of 68-295 deg C, and saLinities of 2.9-13.7 equivaLent wtr. NaCl. saLinities are sLightly highe- than those observed for I
~

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r.;maa-- MICROGRAPHICS BUREAU ...- - - - - - - - - - - - - - - - - - - - . Taube & Van der He Lder (1983) and Large & Both (1980) propose a submarine voLcanogenic origin on the basis of features simi Lar to those observed fro Kuroko-type massive suLphide deposits:i) expLosive feLsic voLcanism produced footwaLL pyrocLastics. ii) Hydrothermal exhaLation along 2 north-northeast fissures resuLted in silicification of unconsolidated footwalL sequence. iii> Chlorite-sericite aLteration and pyrite-chalcoRyrite stringer, deve Lopment be low sea floor. Do lomi te-pyrite depos ited on sea fLoor. iv) Go Ld-cha lcopyri te p rec ipitati on in hottest zones of hydrotherma l fissure belol4 sea fLoor and within massive suLphide on sea floor. sphalerite, galena precipitated downs lope. v) FLuids issuing from penecontemporaneous fauLt precipitated main massive sulphide-barite mineralisation accompanied by deposition of carbonate-talc-chlorite facies distal from suLphide-barite facies. vi) Waning of hydrothermaL activity; deposition of si Ltstone-chert-tuff and greywacke from distaL sources (nanging-wall sequence). vii) Andesite and qual·tz-feldspar porphyry intrusion. Later folding. yanbe & Van der Helder (1983) and Large & Both (1980) propose a submarine voLcanogenic origin on the basis of features simi lar to those observed for Kuroko-type massive sulphide deposits:1) exp Los;ve fe lsic volcanism produced footwaLl pyroclasitcs. ii> Hydrothermal exhaLation along 2 north-northeast fissures resuLting in silicification of unconsoLidated foot wall sequence. iii) Chlorite-sericite aLteration and pyrite-chalcoRyrite stringer development below sea floor. Dolomite-pyrite deposited on sea fLoor. iv) GoLd-chalcopyrite precipitation in hottest zones of hydrothermal fissure below sea floor and within massive suLphide on sea floor. SPhalerite, galena precipitated downs lope. v) Fluids issuing from penec~ntemporaneous fauLt precipitated main massive suLphide-barite mineralisation accompanied by deposition of carbonate-ta lc-chlorite facies distal from suLphide-barite facies. vi) Waning of hydrothermaL activity; deposition of siLtstone-chert-tuff and greY~lacke from distaL souces (hanging-wa LL sequence). vii) Andesite and quartz-feldspar porphyry intruslon. Later folding. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Mount chaLmers REGIONAL SETTING: BERSERKER GRABEN Mount Chalmers is a massive suLphide deposit in caLc-alkaline volcanicLastic rocks of the Berserker Graben. The Berserker Graben deveLoped in the early permian as an activeLy subsiding fault trough at the eastern edge of the YarroL Shelf. The north west-trending graben is 120 km x 5-15 km and is occupied by the Berserker Beds, 3000 m of submarine feLsic to intermediate vOlcanics and overlyi ng vc lcani clasti c sediments. The centra l po rtion 0 f the exposed sequence ;s made up of a series of interfingering north-south belts. Mount Chalmers lies within the most easterLy beLt, the rhyoLite series, which is overlain to the west by the andesite series. The Berserker Beds are gently foLded about north-northwest trending axes and intruded by andesite dykes and si Lls and quartz feldspar' porphyrY dykes. GEOLOGICAL SETTING: MOUNT CHALMERS The pyroclastic sequence at Mount Chalmers comprises:1) Footwall sequence (thickness 40-80+ m) - siliceous strongLy aLtered rhyoLitic to dacitic Lithic tuffs with variabLe fragmental character. Eutaxitic textures indicate at Least partLy terrestriaL deposition. The footwaLl sequence is exposed only in the deposit area. i1) MineraLised sequence (0-110 m) - intensely altered ash tuft or si ltstone which may be pyritic near the oreboaies. A~laY from the ore zones shaLe is the dominant Lithology. MineraL isation occurs in two elongate paraLLeL Lodes each composed of a

!a..

(ti]j_AGPS _ _....

...---MICROGRAPHICS

BUREAU--------------------..

lower zone of si licl '0 stringer ore (0-75 m thick) and an upper massive sUlphide zone (0-15 10. in part bedded and fragmental. A bedded dolomite-PYrite unit (6-20 m) of limited extent may be a facies variant of the massive sulphide. The Main Lode is immediate ly overlain by an intense ly sericitised hod zon which extends beyond the orebody as a stratigraphic unit. iii) hanging-wall tuffs(20-140+ m) - well-bedded s lumped and contorted feldspathic rhyolitic and rhyodacitic crystal tuffs and si ltstones which generally become finer-grained towards the ore hori zon. The hangingwall sequence includes lenses of jasper and hematitic siltstone. The fine-grained sedimentary host to mineralisation marks a change in character between the footwall and hangingwa II volcanic lastics. A large andesite si II transgresses the sequence from the ore horizon to the hanginll-wall sequence. A smaller quartz-feldspar porphyrY intrudes both andeslte and hanging-wall units. APparent doming of the footwall sequence beneath the orebodies, previously interpreted as a volcamc structure (Large & Both, 1980) is no", considered to have resulted from (Jost-ore, late stage horst-block faulting (Taube & Van der Helder, 1983). Gross changes in strat;graphy in the West Lode are attributed to early (penecontemporaneous) fau lti ng. REFERENC ES: Ball L.C. , 1945 Mount chalmers mine. Queens land Government Mi ni ng Journa l 46 p23 Dunstan B. , 1908 Great Fitzroy copper and gold mine. Geological Survey of Queensland. publication 216 Fisher N.H. , owen H.B. , 1952 Mount chalmers copper and gold mine, Queensland. Bureau Mineral Resources, Australia. Report 7 Fle t c he r R. J • , 1 975 Mount chalmers gold-copper deposit. IN Knight C.L. (ed) - Economic geology of Australia and Papua New Guinea. - 1. ~letals. AusIMM. Monograph Series 5 P786-787 Ki rkegaard A.G. , Sha,~ R.D. , ~lurray e.G· ,1970 The geology of the Rockhampton 1 :250 000 sheet are ... Geological Survey of Queensland. Report 38 Large R.R. , Both R.A. , 1980 The volcanogenic sulfide ores at Mount Cha lmers, eastern Queens land. Economic Geology 75(7) p992-1009 MurrayC.G. ,1975 Rockhampton, Queens land, 1 :250 000 geologica l series exp lanatol'y notes. sheet SF/56-13. Bureau Mineral Resources, Australia

-AGPS--....

plIIIII-- MICROGRAPHIeS BUREAU _1

-.

1v Stewart 0.5. , 1980 Gold. Keynote address to the 1980 Annual Conference of the AusIMM, held in Ne~, Zealand by D.S.Stewart, OBE, Chief Executive, peko-Wallsend Ltd. AUSIM~l. Bulletin 441/442 p19-21 TaubeA. ,1980 The Mount Chalmers copper-gold mine. IN Hofmann G.W.(Ed) - 1980 field conference, Mount Morgan-Rundle Range-Yeppoc.n area. 14-16 June 1980. Geological Society of Australia. Queensland Division 1v P60-65 Taube A. , van der Helder p. , 1983 The Mount Chalmers mine and environment - a Kuroko-style volcanogenic sulphide environment. IN Permian geology of Queens Land. proceeCJings of symposium f Brisbane, July 1982. Geological Society of Australia. Queensland Division 1v P387-399 Taube A. , McLeod R.L. , 1987 Mt Morgan mine, Mt Chalmers mine, and UNMC prospect - penecontemporaneous faulting and volcanogenic massive sulphide deposits in central Queensland. IN proceedings, Pacific Rim Congress 87, Gold Coast, Qld, Aug 1987. AusIMM 1v p423-425 0000000000000000000000000000000000000000

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DEPOS IT:

29

MOUNT MORGAN

DEPOSIT IDENTIFICATION:

PRINCIPAL COMMODITIES: Au ,

CU , Ag ,

MINES: Mount Mo rgan , OREBODIES: Main pipe, Mount Morgan , Sugar Loaf , GROUP: Mount Morgan Group COMMENYS: Includes regionaL setting of CaLLiope BLock. regionaL setting of New EngLand FoLd BeLt.

See Deposit No.

35 Gympie for

LOCATION: LATITUDE: 23 39 250K SHEET: SF5613

LO NG nUDE: 150 23 100K SHEET: 8950

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Mount Morgan MINING FIELD: LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1882 OPERATING STATUS AT 1987 MINE Mount Morgan Mount Morgan Mount Morgan

STATUS HistoricaL Comp Le~ed Operatlng

MINING METHO D unde rg round open-Cut Tailings Re-Treatment

COMPANIES: OREBODY: Mount Morgan COMMENTS

PRESENT OPERATORS: Mount Morgan Limited. peko-WaLLsend Ltd.

...

***

M12

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BUREAU--------------.----.....

. . - - - MICROGRAPHICS

EQUITY 40.00 60.00

PRESENT OWNERS: Ang Lo Ameri can Pad fi c Ltd Peko-WalLsend Ltd.

r.

COMMENTS

PRODUCTION: CUMU LA TIV E PRO DUC TION
GOLDCkg) 237,896

RECOVERED GRADECg/t) 4.75

COMMENTS

MAIN PRODUCTION PERIODS: 1886-1927, 1?29-1981 ,1982-, RESOURCES: DATE

OREC'OOOt)

June 198725,300

GRADE(g/t)

GOLDCkg)

CLASSIFICATIOrJ

1.1

27,324

Economic Demonstrated Recoverable - Measured

PRE-MINE RESOURCE SIZE: M GEOLOGY: PROV INCE: BLOCK: Tasman FoLd BeLt PROV INC E: New Eng Land Orogen SUB-PROVINCE: CaLLiope Block HOST ROCKS: Mine Corridor VoLcanics RhyoLitic porphyritic tuff, chert, jasper, LocaL limestone. Mineralisation comprised pipe-Like body of massive plus disseminated/stringer copper-goLd sulphides in altered si liceous volcanics. CapeLLa Creek Beds RhyoLite, dacite, and andesite tuff, sediments. IjnaLtp.red correLative of Mine Corddor VoLcanics. Mount Morgan Tonalite TonaLite; minor granite, alaskite, apLite, diorite, gabbro. Mine Corridor VoLcanics occur as roof pendant in tonaLite. pre-dated tonalite intrusion.

Mineralisatiol1

AGE: PaLaeozoic Middle Devonian STRUCTURAL FEATURES MAJOR: Faulting, FoLd Axis, Fracturing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS

..

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IGNEOUS PROXIMITY MAJOR: plutonis m(Gran ite) , AGE OF INTRUS ION: pa laeozoi c Late Devoni an METAMORPHISM: The volcani cs away from the orebodl' show regiona l chlorite -epidot e calcite diagene tic-buri a l metamor pllism. The orebodY h3s been subj ected to annealin g metamor phism as a result of Middle Devonia n intrusio n. ALTERAn ON: The orebody was largely surround ed by a series of alterati on zones massive siLicif icatlon , accompa nied by pyritis ation. alterati on mantle extends up to several hundred metres The total progres sing outward s from the orebody , the zones are:- from the ore. i) recryst allised quartz and dissemi nated sulphid e ii) recrysta llised quartz porphyr y i i i ) quartz porphyr y iv) quartz- fe ldspar porp hyry v) serecit e-chlor ite replacem ent (overlap s ii) and i i i ) . Si02, K20, Fe + S (=pyrite ) increas e towards the orebody as Al203, Na20 (feLdsp ar disinte gration ), CaO and MgO decreas e. Zone iii) extends to at Least 750 m. The mineral isation- associa ted aLterat ion is overpri pyrite aLterat ion associa ted with tonaLite intrusio nted by chLorit en and by hydroth ermal aLterat ion associa ted with younger pebbLe dYkes and breccia pipe~.

=

DEPOSIT CHARAC

TERISTICS: ----------------------TYPES: Massive copper- gold suLphid e in felsic volcani cs (volcan ogenic) . STYLE: stratabo und , MORPHOLOGY: Irregu lar, pipe-L ike, AGE OF MINERALISA nON: pa laeo zoi c MiddLe Devonia n DIMENS IONS: OREBODY: Main pipe

MIN

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Mount Morgan

( m ( m ( m

120.0

STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH OREBODY: Sugar loaf

m m m

100.0 130.0

TRUE WIDTH STRIKE LENGTH VERTICAL DEPTH

m m m

MIN

~lIN

AVE

AVE

AVE

MAX 640.0 250.0 200.0 ~lAX

750.0 270.0 200.0 MAX 100.0 300.0 130.0

NATURE OF MINERALISATION:

..._ _...

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A13

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_1IIIIIlIII'"

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.-&iII

............1I!IIJIII

Disseminated, Massive, oxidised, primarY, PRIMARY ORE: pipe , MINERALOGY: OREBODY: Mount Morgan sulphide ore: pyrite, quartz, pyrrhotite, chalcopyrite, magnetite, sphalerite. Gold occurred as ultrafine to submicroscopic cisseminations of native gold, gold-copper alloy, and electrum, and as gold tellurides (sylvanite, calaverite, petzite). Accessory minerals inc luded arsenopyrite, bismuthinite, bornite, brochantite, calaverite, cassiterite, chaLcocite, coloradoite, covellite, cubanite( cuprite, digenite, galena, hessite, molybdenite, petzite, tellurob1smuthite, tetradymite and tetrahedrite (Cornelius, 1969). Oxide ore: silica, hematite, goethite, gold, trace malachite, azurite, chalcanthite, cuprite, native copper. GENETIC CONTROLS: structural - deposit is located on axis of major regional anticline, in area of complex faultina. Local structural feature is stratigraphic dome. Form of orebody 1S epigenetic pipe, but minor strati form pyrite mineralisation occurs in the Banded Mine sequence. Lithological. - deposit is localised in fels1c unit within predominantly intermeaiate pyroclastic sequence. Chronological - deposit predates tonalite, on the basis of the greater degree of alteration in the volcanic rocks, intrusive features of the tonalite into the altered volcanics, and tne time relationships of the quartz keratophyre intrusions, whicn intrude the ore and are themselves , nt ruded by tona lite. Alteration - alteration increases in intensity outwards from the orebody and is greatest beneath the mineralised zone. Fluid inclusion data indicate homoaenisation temperatures of 183-265 deg and salinity of 6-11 equivalent we1ght X NaCl. The salinity values are higher than values observed from Kuroko-type volcanogenic sulphides and from seawate r. However 0 xygen isotope data (Go ldi ng & Wilson, 1981; Golding & others, 1987) indicated a seawater ore-fluid source, and hence a volcanogenic massive sulphide origin for the mineralisation. GENETIC MODELS: The origin of Mount Morgan has been debated since its discoverY· Many earlier workers favoured a hydrothermal epigenetic origin, most proposing the Mount Morgan Tonalite as the ore-fluid source, e.g. Fraser (1914), conolly (1952), shep.herd ('1960), Hawkins & Wnitcher (1961). Reid (1947) related the mineralisation to late mafic dykes. Cornelius (1969) described the orebody as a breccia pipe and suggested that mineralisation was related to an inferred permian intrusive at depth. He considered that most of the quartz porphyry host rocks were sha llow intrusives in the upper zones of the batholith. The host porphyries are now known to represent tuffaceous units withi n a volcanic sequence. paltridge (1967), LawrenCe (1974 and earlier p'apers), and Gibbons (1974) compared Mount Morgan to Kuroko-type massive sulphide deposits. Frets & Balde (1975) considered the orebody to be of partly transgressive epigenetic hydrothermal oriain coeval with volcanism. Taube (1986) proposed a volcanogenic mass1Ve sUlphide origin, modified bX extensive subsequent metamorphism and deformation, and overpri nting of earlier features by later alteration and r ineralisation, mostly re lated to the tona lite emp lacement:i) Development of volcanic vent in island arc and extrusion of submarine and terrestrial felsic volcanics (Lower Mine PYroclastics). ii) cauldron subsidence during quieter phase and opening of hydrothermal vent along bounding fault of subsiding graben; hydrothermal alteration

***

B13 >~**

-AGPS----

.....--MICROGRAPHICS

BUREAU--~----------------"

of adjacent voLcanic pile to form aLteration pipe aLong originaL fracture. iii) precipitation of suLphides by repLacement in upper part of pipe be Low the sea fLoor; contemporaneous deposition of the Banded Mine Sequence above the pipe on the sea floor. iv) CauLdron resurgence upLift and expLosive voLcanic activity, which terminated the ore-forming stage and resuLted in deposition of Upper Mine pyrocLastics; doming of sequence. v) Intrusion of quartz keratophyre = precursor of Mount Morgan TonaLite. The tonaLite stoped upwards into the pipe, forming a pLuton in the vent site. Addition of tell.uride mineraLs to ore assembLage; earLy fauLting (FootwaLL and rotationaL fauLts). vi) continued voLcanism and Late stage hydrothermaL activity, aLteration of tonaLite. vii) Orogenic upLi ft, intrusion of Permian dykes.

=

GEOLOGICAL SETTING OF MINERALISATION: OREBOOY: Mount Morgan Mount ~iorgan is situated in the northern part of the caLLiope BLock. The bLock is a partly fauLt-bounded remnant of the CaLLiope IsLand Arc, the earLiest voLcanic arc system of the NeW Eng Land FoLd BeLt. The orebodY consisted of a pipe-Like body of massive and disseminated ?voLcanogenic copper-goLd suLphide mineraLisation in a roof pendant of aLtered feLsic pyrocLastics intruded by Late orogenic tonaLite. REGIONAL SETTING: CALLIOPF. BLOCK The caLLiope Arc deveLoped at the end of the Si Lurian either as an emerging isLand arc separated from the AustraLian continent, represented by the Anakie InLier, by a marginaL sea, or as a broader voLcanic arch accretinQ on the continentaL margin. Tne arc was destroyed by orogen e sls in the MiddLe oevonian. The bLock was the site of voLcanism and sheLf and minor terrestriaL sedimentation throughout the Late Oevonian and the Carboniferous. The oevonian voLcanogenic sequence comprises 7500+ m of feLsic to intermediate tuffs and fLows, with interbedded shaLLow marine voLcanogenic sediments, of tne EarLy-MiddLe oevonian Mount HoLLy Beds and CapeLLa Creek Beds, unconformabLy overLain by Late oevonian intermediate voLcanics, cLastics, ana voLcanicLastics of the Oee VoLcanics, Thomson cLastics, and BouLder creek Grit. In the deposit region the EarLy-Middle Oevonian units are exposed in the core of a compLex major regionaL anticLine,_ the Gracemere Anticline. The anticlinaL axis, which extends for 70 I
-AGPS--..D

.----MICROGRAPHiCS BUREAU

-.s_~

_s

sediments and quartz-feldspar crystaL-lithic tuff with turbidite structures. iii) Upper Mine pyroclastics (porphyries) (750 m) - coarse quartzfe Ldspar c rysta l- Lithi c tuft. iv) Felsite units (460+ m) - siLiceous aphanitic rock and crystal ash tuff (quartz feLdspar I?orphyry). The sequence dips shaLLow Ly northeast in the southern Jlart of the Mine Corridor( where a gentLy plunging open anticLine is defined by the Banded Mlne Sequence. Dips are steeper east of the mine and in the northern part of the corridor. The orebody. occurs in the core of a gentle domaL structure. The ear Y Trough fault and FootwalL fauLts have rotationaL movements around the orebody and from south to north; the arcuate west-dipping FootwaLL fauLts form the orebodY's northeastern margin. A major Late fauLt/fracture system is defined by the permian SLide and BaLLard's fauLts, which are part of a primary regionaL falJLt zone. The SLide fauLt cuts obLiqueLy across the southwestern extent of the orebody and dispLaces it 60 m downwards on the southeastern side. The orebody was an irreguLar quartz-pyrite mass within the 2 Lower units of the Mine Corridor sequence, the Lower Mine pyroc Lastics and Banded Mine Sequence. OveraLL shape was that of an irreguLar pipe-Like body pLunging shaLLowLy southwest. The orebody consisted of 2 principaL types of ore - massive pyrite in the Main pipe, which constituted about 701 of the totaL ore, and siLiceous disse~inated and stringer mineraLisation in the sugarLoaf orebody. The orebody had a sharp boundarY onLy in the northeast. It was eLsewhere enc Losed in an envelope of Low-grade quartz-pyrite with a decrease in Au and ClI content from the centre of the mass outwards. GoLd was enriched in the uPl?er portion and copper in the Lower portion of the orebody. Brecciation and pseudo-brecciated textures associated with Main pipe mineraLisation (CorneLius, 1969) are in part formed by anastomosing quartz veining or stringer mineraLisation (Taube, 1986). The sugarLoaf orebody Lay adj acent to and stratigraphicaLLy LateraLLy beneath the Main pipe orebody on the southwest. The ~lai n Pipe was over Lai r. by Au-enri ched gossan and mundi c zone~. REFERENCES: AustraLian Mining. 1974 Mount Morgan - the 88 year oLd mine. AustraLian Mining 66(12) P24-29 ConnoLLy H.J.C. , 1952 Report on Mount Morgan. Mount Morgan Ltd. unpubLished Report 1v CorneLius K.D. , 1967 Breccia pipe associated with epigenetic mineraLi zation, Mount ~lorgan, Queens Land. Economic GeoLogy 62 (6) P853-860 CorneLius K.D. , 1969 The Mount Morgan mine, QueensLand. repLacement deposit. Economic GeoLogy 64(8) p885-902

....._ _. -

A massive goLd-copper pyrite

- - - - - I l l 1 i J I - A G P S - -...

..... .-MI CRO GRA PHIC S BUREAU - - - -....- - - - - - - - - - - - - - -... .. DaLy J. , Doyle H.A. ,1961 Mt. Morgan geophys ical surveys , Queens 1949. Bureau of MineraL Resourc es, AustraL ia. Land Record 61/158 Dunstan B. , 1901 Some Mount Mo rgan mi nes. Queens Land Governm ent Mi ni ng J ou rna l 2 p258-261 Eadingto n P.J. , smith J.W. , WiLkins R.W.T. , 1974 Fluid incLusio n and sulp,hur isotope researc h, Mount Morgan, QueensL and. AusIMM. confere nce Se,1es 3 p441-44 4 Fedi kow M.A.F. , Govett G.J .S. , 1985 Geochem icaL a Lteratio n halos around the Mount Morgan goLd-co pper deposit , Queens Land, Aust ra l i a. JournaL of Geochem icaL ExpLora tion 24 (3) P247-27 2 Fedikow M.A.F. 1982 Rock geochem icaL , exp Loration at Mount Morgan, Queens Land. univers ity of New South WaLes. UnpubLi shed 1v

ph.D.

thesis.

Fraser c. , 1914 GeoLogi caL report on Mount Morgan mine. Mount Morgan Ltd. unpubLi shed Report 1v Frets D.C. , 1971 Mount Morgan mine geoLogy . GeopeKo Ltd. unpubli shed Report 66 Frets D.C. , 1974 Rock reLation ships and mineraL isation Mount Morgan. IN AUlIMM AnnuaL confere nce, Souther n and central QueensatLand, Brisban e, JuLy 1 n4. AusIMM. confere nce series 3 P425-44 0 Frets D.C. , saLde , 1975 Mount Morgan copper·-R. gold deposit . IN Knight C.L. (ed) - Economi c geology of Austral ia and Papua New Guinea - 1.MetaL s. AUS IMM. Mo nog rap h Se ri es 5 P779-78 5 GabyW. E. ,1916 petrogra phy of the Mount Morgan mine, Queens Land. America n Institu te of ~lining Enginee rs. Transac tions 55 P263-28 3 Geopeko Staff. , 1968 The geology of Mount Morgan mine and surroun ding area. r-tJrra)l C.G.(ed s) - 1968 field confere nce, Rockhampton-~I IN ELLis p.L. & ount Morgan area, June 8-10 1968. GeoLogi ca{ Society of AustraL ia. QUeensL and Division 1v p29-33 Gibbons G.

, 1974

,~**

E13

,~**

... AGPS

.-J

.---M ICR OGR APH ICS

BU RE AU --- --- --- --- --- --- -

1IIlIIIJIRII

Mi nera logi ca L studies at Mount Morgan, Queens Land. AusIMM. confere nce series 3 P445-46 3 Golding 5.0. , Wi Lson A.F. , 1980 The appLica tion of oxygen isotope studies to the occurre nce of goLd mineraL ization in eastern AustraL ia. IN AusH1M Confere nce, New Zealand , May 1980. AUSIMM. confere nce series 9 P67-80 GoLding 5.0. , WiLson A.F. , 1981 An oxygen and carbon isotopic study of some goLd deposit ~ of eastern AustraL ia. AusIMM. proceed ings 278 P13-21 Golding 5.0. , Wi Lson A.F. , Scott M. , Anderso n P.K. , Waring C.L. , Flitcro ft M. , Rypkema H.A. , 1987 Isotopi c evidenc e for the diverse origi ns of go Ld in Herbert H.K.(ed ) - Gold in QueensL and. proceed ings Queens Land. IN of one-day symposiu m, univers itY of Queens land, 1984. univers ity of QueensL and. June Departm ent of GeoLogy . papers 12 (n P6S-83 Hart G.S. , 1912 Further notes on the geoLogy of Mount Morgan. AUsIMM. proceed ings 6 Supp Lement 1 (10pp) Hawkins B. , Whitche r 1. (1961 GeoLogi caL environm ent of tne Mc'unt Morgan orebody . Enterpr ise EXP Loration Co. pty Ltd. unpubli shed Report 1v Jack R.L. , 1884 Mount Morgan goLd deposit s. GeoLogi caL survey of Queensl and.

17

pubLica tion

J ac k R. L. , 1 884 Mount Morgan goLd deposit s. Report to Queens Land Governm ent 1,2,3 Jack R.L. , 1892 Third report on the Mount Morgan gold deposit . GeoLogi caL Survey of QueensL and. pubLica tion 83 Jack R.L. , 1898 Mount Morgan and other mines in the Crocodi le goLdfie Lds. Geo Logi ca L Survey of QUeens Land. pubLica tion 132 P1-7 Kirkega ard A.G. , shaw R.D. , Murray CoG. ,1970 The geo logy of the Roc khampto n 1: 250 000 GeoLogi caL survey of QueensL and. Report sheet a rea.

38

Lawrenc e L.J.

.....

, 1967

,~**

F13

*~,* ~-AGPS

..

--

.---MICROGRAPHICS

BUREAU-----~-----------~--.

A mineragraphic study of Mount Morgan copper-gold ore. AusIMM. proceedings 223 p29-47 Law rence L.J. , 1974 The nature and origin of the ore minerals of Mount Morgan. AusnlM. conference series 3 P417-424 Le Messur'ier P. , 1969 Mineralogy and ore textures, Mount Morgan orebody. Geopeko Ltd. Seminar paper. unpublished 1v Maxwell W.G.H. , 1953 Upper PaL;Jeozoic formations in the Mount Morgan district - stratigraphy and structure. University of Queensland. Department of Geology. Papers ll(4) P1-14 Mount Morgan Ltd. , 1965 The Mount Morgan mine. IN McAndrew J.(ed) - Geology of Australian ore deposits. 8th commonwealth Mining & Metallurgical Congress, Australia & New Zea land, 1965, Me Lbourne. Ausnl~l

1 p364-369 Mount Morgan Ltd. (1980 Copper-goLd ore mimn;l at Mount Morgan Limited, Mount Morgan, Qld. IN Woodcock J.T.(ed) - Mlning and metaLlurgicaL practices in Australasia. (Si r Mauri ce Mawby Memori a l Vo lume). AUs IMM. Monog rap h Se ri es 10 p302-304 Mount Morgan Ltd. Staff. , 1968 The historY of Mount Morgan Limited. IN ElLis P.L. & Murray C.G.(eds) 1968 field conference, Rockhampton-Mount Morgan area, June 8- 1 0, 1968. Geological Society of AustraLia. Queensland Division 1v p28 Murray C.G. , 1975 Rockhampton, Queens land, 1 :250 000 geologica l series exp lanatory notes. Sheet SF/56-B. Bureau Mineral Resources, AustraLia 1v Newman J.M. , campbe Ll-Brown G.F. , 1910 Notes on the geology of Mount Morgan· Queens land Government Mi ni ng Journa l 11 p334-337 Newman J .M. , campbe Ll-Brown G.F. , 1911 Notes on the geology of Mount Morgan. AusIMEng. Transactions 20 p439-470 paltridge I.M. , 1967 Breccia pipe mineralization at Mount Morgan - a discussion. Economic Geology 62 (6) P861-862

***

G13

,,*i,

-AGPS---.III

..---MICROGRAPHICS BUREAU-----......- - - - - - - - - - - - -... patte rson B.G. , 1950 The story of the Mount Morgan mi ne. Queens land Government Mi ni ng Journa L 51 p370-392 Reid J .H. , 1947 The Mount Morgan orebody. Mount Morgan Ltd. UnpubLished Report 1v shepherd 5.R.L. , 1938 Mount Morgan mine. Queens land Government Mining Journal 39 P297-301 Shepherd 5.R.L. , 1960 The Mount Mo rg an mi ne • GeoLogical Society of Australia. 7 p162-164

Journal

shepherd 5.R .L. , 1960 Geological report on the Mount Morgan mine. Mount Morgan Ltd. Unpublished Report 1v Staines H.R.E. , 1952 The geo logy of Mount Morgan. Aus IMM. P roceedi ngs 166-167 P47-69 Staines H.R.E. , 1953 Mount Morgan copper and gold mine. IN Edwards A.B.(ed) - Geology of Australian ore deposits. 5th Empire Mining Metallurgical Congress, Australia & New zealand, 1953, Melbourne. AusIMM 1v p732-7S0 5tewart 0.5. , 1980 Gold. Keynote address to the 1980 Annual Conference of the AusIMM, held in New Zealand by D.S.Stewart, OBE, Chief Executive, peko-WaLlsend Ltd. AusIMM. Bulletin 441/442 P1 9-21 Taube A. , 1980 The Mount Morgan copper-gold mine. IN Hofmann G.W.(Ed) - 1980 field conference, Mount Morgan-Rundle Range-Yeppoon area. 14-16 June 1980. GeologicaL Society of Australia. Queensland Division 1v P40-S0 Taube A. , 1986 The Mount Morgan !;jold-coiJper mine and environment, Queens land: a volcanogenic maSSlve sulfide deposit associated with penecontemporaneous fau Lti ng. Economic GeoLogy 81 (6) P1322-1340 Taube A. , 1987 The Mount Morgan !;joLd-copper mine and its environment, Queens land - a voLcanogenic maSSlVe suLphide deposit associated ~,;th penecontemporaneous faulting. IN Herbert H.K.(ed) - GoLd in Queensland. Proc. of one-day symp., un;' QLd, June 1984.

.-.

,bh~

H13

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..

~-AGPS--

....--MICROGRAPHICS B U R E A U - - - - - - - - -...- -....- - - - - -..... university of Queens Land. 12(1) P126

Department of Geo Logy.

Papers

Taube A. , McLeod R.L. , 1987 Mt Morgan mine, Mt ChaLmers mine, and UNMC prospect - penecontemporaneous fauLting and voLcanogenic massive suLphide deposits in centraL Queens Land. IN Proceedings, paci fic Rim Congress 87, GO ld coast, QLd, Aug 1987. AusIMM 1v P423-425 WiLson J.B. , 1911 The Mount Morgan ore deposits. Institution of Mining and MetaLLurgy. 20 p89-103

Transactions

0000000000000000000000000 000000000000000

~

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113 ***

-IliiID-AGPS--"

fIIIIIII.II--MICROGRAPHICS

DEPOS IT:

30

BUREAU--------------------.

MOUNT CANNINDAH

DEPOSIT IDENTIFICATION: PRINC IPAL COMMODITIES: AU , A9 , CU , MINES: Mount Cannindah , Mount cannindah East, Mount Cannindah Mine, OREBODIES: Mount Cannindah , Mount Cannindah East, Mount Cannindah Mine, GROUP: permo-Triassic Igneous Group COMMENTS: Includes regional setting of Yarrol Block. see Deposit No. 35 Gympie for regional settin~ of New Eng land Fold Belt; Deposit No. 34 Ki lkivan for setting of Permo-Triasslc igneous group. LOCATION: LATITUDE: 24 55 2501< SHEET: SG56 1

LONGITUDE: 151 17 100K SHEET: 9148

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Eidsvold f4INING FIELD: LOCALITY: ~~VELOPMENT

HISTORY: DISCOVERY METHOD Prospecting

'JISCOVERY YEAR 1889 ,I:.RATING STATUS AT 1987 MINE Mount Cannindah Mount Canni nda h East Mount Cannindah Mi ne

STATUS possi ble possible

~fINING METHOD Open-Cut Open-Cut

possible

Open-Cut

COMPANIES: ORE80DY: Mount Cannindah COMMENTS

PRESENT OPERATORS: Astrik Resources N L.

rdmma

~'n't'!(

J 13

**-1:

ffiJiil- AGPS - _...

l'JlII'l.IIl--MICROGRAPHICS

BUREAU-------------·--~--.-. EQUITY 70.00 30.00

PRESENT OWNERS: Ast ri k Resources N L. M I M Ho Ldi ngs Ltd. OREBODY:

r.

COMME~TS

Mount cannindah East COMMENTS

PRESENT OPERATORS: Astrik Resources N L. EQUITY 70.00 30.00

PRESENT OWNERS: Astrik Resources N L. M I M Ho Ldi ngs Ltd.

r.

CO~lMENTS

OREBODY: Mount cannindah Mine COMMENTS

PRESENT OPERATORS: Astrik Resources N L. EQUITY 70.00 30.00

PRESENT OWNERS: Astrik Resources N L. M I M HoLdings Ltd.

r.

COMMENTS

PROJUCTION:

-----------

CUMULATIVE PRODUCTION
GOLDCkg) 1,000

RECOVERED GRADEC9/t) 0.00

COMMENTS Ore tonnage not avai LabLe. Zero figures resuLt from program caLcuLations.

MAIN PRODUCTION PERIODS: 1906-1918 , RESOURCES: DATE

OREC'OOOt)

GRADEC9/t)

GOLD Ckg)

CLASSIFICATION

Dec 1987

682

2.4

1,657

Demonstrated submarg i na L

146

2.0

294

Dec 1987

105

2.8

290

Dee 1987

3,050

Dec 1987

0.9

2,745

D~monstrated

In-Situ

o/c

In-situ

olc

submargina L Sub-Economi c Infe rred In-Situ

o/e

In-Situ

o/e

Sub-Econom i c Demons t rated

Mt canni ndah proven Mt cannindah probabLe Mt Canni ndah possibLe Mt cannindah

East East East Mine

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman FoLd BeLt

....

...

~-AGPS--

pIIIIII-- MICROGRAPHICS BUREAU -------------------1 .a

PROV INCE: New Eng Land 0 rogen SUB-PROVINCE: Yarrol BLock HOST ROCKS: CasweLL Creek Group Mudstone, si Ltstone, greywacke, congLomerate, Limestone. MineraLisation occurs in breccia zones, fractures, and veins mudstone-siLtstone at the contact between sediments and dacite intrusive. porphyritic dacite dYke. MineraLisation occurs at intrusive contact of dacite. mineraLisation. AGE: paLaeozoic EarLy Carboniferous

?GeneticaLLy

related

in to

STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: Intrusive Contact, IGNEOUS PROXIMITY MAJOR: sub-VoLcanism(FeLsic porphyry) , AGE OF INTRUSION: Mesozoic Triassic AGE OF INTRUSION: paLaeozoic permian ALTERA TION: MineraLisation is accompanied by hydrothermaL aLteration: fractures and breccia fra~ment margins are intenseLy bLeached. The ad~acent dacite is aLbit1sed, epidotised and pyritised. pLagiocLase 1S heaviLy saussuritised and sericitised, aLthough this couLd be a weathering effect. DEPOSIT CHARACTERISTICS: TYPES: Breccia and disseminated/quartz stockwork copper-goLd in sediments adjacent to fe Lsic/intermediate porphyrY intrusive (porphyry copper-goLd). STYLE: Discordant, Stratabound , MORPHOLOGY: Lenti cuLar , AGE OF MINERALISATION: paLaeozoic permian DH1ENS IONS: OREBODY: Mount Cannindah STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION

m

m m m

~lIN

AVE 35.0

MAX 175.0 60.0 400.0

NATURE OF MINERALISATION:

f,**

L13

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-----------------------[ii]j-AGPS--1IIlII

..----MICROGRAPHICS

BUREAU---------------------

PRIMARY ORE: Breccia , mNERALOGY: OREBODY: Mount Canni ndah Su lp hide zone: c ha lcopyri te and pyri te domi nate; mi nor spha leri te, marcasite, molybdenite, silver, and gold. oxide zone: cha lcoci te. GENETIC CONTROLS: ~lineralisation is controlled by the dacite intrusive. The disposition of ore zones within the breccia indicate that control was also part ly structura l. GENETIC MODELS: Ore emplacement and alteration post-dated dacite intrusion, possibly rep~esenting late stage hydrothermal activity associated with the daclte. GEOLOGICAL SETTING OF

r~INERALISATION:

,

,

OREBODY: Mount cannindah Mount Cannindah lies in the narrow southern fault-bounded portion of the Yarrol Block. The deposit is a porphyry copper(-gold-si lver) deposit associated with an isolated dacite intrusion assigned to the Late Pe rmi an igneous p rov i nce. REGIONAL SETTING: YARROL BLOCK The Yarrol Block contains thick sequences of volcaniclastic and shallow marine sediments, to~ether with interbedded primary volcanics and oolitic arenites, WhlCh were deposited on a narrow continental shelf (forearc basin) on the eastern seaward flank of an Andean-type continental margin volcanic arc. (Connors Auburn Volcanic Arc - see Deposit No. 35 Gympie). The shelf, the Yarrol shelf, formed over folded Siluro-Devonian basement rocks of the Calliope Island Arc, and received maximum sedimentation in the Early carboniferous. Deposition was dominated by volcaniclastic material derived from the volcanic arc to the west, with admixed volcanics and transported shallow marine sediments. The host to mineralisation at Mount Cannindah, the Caswell Creek Group, occurs at the top of the Early carboniferous succession. The Yarrol Shelf received restricted shallow water marine sediments and volcanics in the permian following stabilisation of the Connors-Auburn Arc at the end of the carboniferous. The shelf sequence was deformed in the Late permian. Deformation was accompanied by the emplacement of serpentinite on major faults, inc luding the Yarrol Fault east of Mount Cannindah. The yarrol Block was uplifted and stabi lised with the emplacement of post-orogenic plutonic complexes in the Late permian to Late Triassic. The main plutonism affected the northern part of the block. In the south the Yarrol Block was less extensively intruded, but lies between the 2 principal Permo-Triassic plutonic belts - in tne Gogango Overfolded Zone to the west and in the Yarraman and Gympie BLocks to the east. Triassic volcanic activity was concentrated in the Abercorn and Esk Troughs, but in the deposit region volcanism extended across the yarrol BLoCK with the extrusion of the Muncon Volcanics. The permo-Carboninerous sequence is block-faulted by a series of northnorthwest ~rendi ng faults. GEOLOGICAL SETTING: MOUNT CANNINDAH The caswell Creek Group consists of calcareous feldspathic and lithic subgreywacke, mudstone, cong lomerate and oolitic limestone. North of Mount Cannini::tah it is intruded by the Middle-Late Triassic Glassford

..

~

__

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M13

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..

...---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - a complex and overlain by the comagmatic t1Jncon Volcanics. Mount Cannindah lies near the faulted contact between Caswell Creek Group and Muncon Volcanics. The Glassford Complex consists of hornblende-biotite granodiorite and adamellite( and tonalite. The Muncon Volcanics are andesitic and trachytic Lavas, tuff, agglomerate, conglomerate, tuffaceous sandstone, mudstone and carbonaceous shale. A Late Permian-Early Triassic granodiorite batholith crops out 20 km east of Mount cannindah in the Coastal Block. copper-gold mineralisation is hosted by massive altered tuffaceous mudstone-siltstone and is localised in breccia and associated veins and fractures at the contact between mudstone and a ?permian porphyritic dacite intrusive complex. The sediments dip southeast at 25-30 deg and form part of the western limb of a southerly-plunging syncline, of which the axial plane parallels the Yarrol Fault. The felsic dyke is 250 m wide and dips west at 60-70 deg. It is jJredominantly altered porphyritic dacite with local variants of tonalite, andesite, quartz andesite and granodiorite. The deposit is faulted and cut by barren but hydrothermally altered post-ore dykes. Brecciation is mostly confined to the mudstone. cavities are infilled with small dacite fragments, and quartz-calcite-sulphide cement. Within the mineralised breccla, mineralisation forms en echelon tabular bodies parallelling the dacite-mudstone contact. REFERENCES: Bedford I.V. 1975 Mount Cannindah copper deposit in Knight, C.L.(ed) - Economic geology of Australia and Papua New Guinea - 1. Metals. AusIMM. Monograph series 5 P787-789 Dear J.F. , McKellar R.G. 6 Tucker R.M. ,1971 Geology of the Monto 1:250 0 0 sheet area. Geological Survey of Queens land. Report 46 Fletcher R.J. , 1975 The geology and mineralization of the Mount cannindah mineral field, south-east Queens land. M.Sc. thesis James Cook University, North Queens land. Unpublished 1v

0000000000000000000000000000000000000000

1iau1lllGll!l_1BIl!IIII_1lElilIl_ _

**,~ IIIIIDlIIl!-.rZlIIIJlllIIII_~

N13 *** ~

_

AGPS _ _...rI

....-- MIC ROG RAP HIC S B U R E A U - - ---------------DEPOSIT:

31

- -.....

MOUNT RAW DON

DEPOSIT IDENTIFI

CATION: --------------------PRINCIPAL COMMODITIES: AU , Ag , MINES: Mount Rawcfon , OREBODIES: Mount Rawcfon , GROUP: Permo-T riassic Igneous Group COMMENTS: Include s regiona l setting of G)'mpie Block. See Deposit regiona l settin~ of New England Fold Belt; Deposit No. NO. 35 Gympie for 34 Kilkiva n for setting of permO-T rlasSlC 19neous group. LOCATION: LATITUDE: 25 17 250K SHEET: SGS66

LONGITUDE: 1S1 45 100K SHEET: 9247

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Eicfsvol d MINING FIE lD: LOCALITY: DEVELOPMENT HIS

TORY: -------------------DISCOVERY YEAR 1946 OPERATING STATUS AT 1987 MINE STATUS Mount Rawdon Histori cal Mount Rawdon Possibl e

DISCOVERY METHOD P rospec ti ng MINING METHOD Unde rg round Open-Cu t

COMPANIES: OREBODY: Mount Rawdon PRESENT OPERATORS: Placer Explora tion Limited . PRESENT oWNERS: Placer EXP loration Limited .

COMMENTS EQUITY % 70.00

COMMENTS

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15.00

PRODUCTION: CUMULATIVE PRODUCTION
COMMENTS

MAIN PRODUCTION PERIODS: (1951-1953) , RESOURCES: DATE

ORE('QOOt)

GRADE(g It)

GOLD(kg)

CLASSIFICATION

Dec 1987

21,960

1.2

25,912

Demonstrated submarg;na L

In-Situ

o/c

PRE-MINE RESOURCE S nE: M GEOLOGY: PROV INCE: BLOCK: Tasman FoLd Be Lt PROV INCE: New Eng Land orogen SUB-PROVINCE: GymPie BLock HoST ROCKS: Aranbanga Beds RhyoLite, andesite, and trachyte fLows al1d pyroc Lastics. Mi nera Li sation consists of inverted cone-shaped zone of dissemi nated and stockwork-controLLed goLd-silver suLphide in hydrothermaLLy aLtered tuff intruded by dacite and trachYandesite dykes. Dacite porjJhyry. Intrudes mineraLised tuff. Trac hyandes i te. Dykes cut mineralised tUff.

?GeneticaLLy reLated to mineraLisation. ?GeneticaLLy reLated to mineraLisation.

AGE: Mesozoi c Late Tr; assi c STRUCTURAL FEATURES MAJOR: FauLting, STRUCTURALlSTRATIGRApfl!C INTERSEC TIONS MAJOR: Intrusive Contact, IGNEOUS PROXIMITY

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MAJOR: P lutonism (Granod iorite) Volcani sm(FeLs ic) ,

Sub-VoL canism( Interme diate)

AGE OF INTRUSION: Mesozoi c MiddLe Triassic METAMORPHISM: RegionaL metamor phic grade is Low greensc hist facies. ALTERATION: The mineraL ised zone is coincid ent a zone of phyLLic aLterat ion that has overpri nted a more widesprwith pervasiv e zone of chLorit ecarbona te repLace ment. The phyLLic ead, zone is charact erised by pervasi ve sericit ic aLterat ion with LocaLLy intense si Licifica tion and argi LLic alterati on. ALL rock units except the trachyte exhibit variabL e repLacem ent by chLorit e, carbona te, sericite and dykes to a quartz and cLay. Minor sericite is present repLacin Lesser degree g the feLdspa r and biotite in the groundm ass of the trachyt e. DEPOS

IT CHARACTERIS TICS: ------------- ------ _... -TypES: Dissem inated/q uartz stockwo rk in feLsic voLcani cs adjacen t to feLsic/i ntermed iate porphyr y intrusiv e. STYLE: Discord ant, MORPHOLOGY: pipe-Li ke , AGE OF MINERALISATION: Mesozoi c Late Triassic DIMENSIONS: OREBODY: Mount Rawdon STRIKE LENGTH TRUE WIDTH VERTICAL DEPTH DEPTH OXIDATION

m m

MIN

AVE

m

m

20.0

MAX 350.0 250.0 270.0

NATURE OF MINERALISATION: Dissem inated, PRIMARY ORE: Stockwo rk , MINERALOGY: OREBODY: Mount Rawdon SuLphid e zone: goLd, pyrite, sphaLe rite, gaLena, chaLco pyrite, bornite , arsenop ¥rite, pyrrho tite. GoLd is cLoseLy aLLied with suLphid es, pyrite in part1cu Lar, sphaLer ite to a Lesser extent. is present in the native state or as eLectrum , and occurs as free GoLd within pyrite, sphaLer ite and chaLcop yrite. GoLdgrains up to 20 microns content paraLLe Ls suLphid e abundan ce. The mineraL ised typicaL ly carries 1-2y' pyrite by voLume, LocaLLy 6Y.. Trace amounts zone of non-aur iferous pyrite extend beyond the goLd zone. The m"ineraL ised zone i:l rimmed by a zinc haLo. Gangue: quartz, ankerit e, chLorit e. GENETIC CONTROLS: ControL s are apparen tLy LithoLo gicaL. isation is reLated to an abundan ce of dacite and trachya ndesite lli:leraL intrusiv es, which may be reLated

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IIIII&I:-..-MICROGRAPHICS BUREAU - - - - - -...- - - - - - - - - . . - - - -..... '!=O the source of the mineraLising fluid. MineraLisation was LocaLised 1n the more permeabLe rhyodacite tuff in preference to the weLded dacite tuft. primarY fLuid inclusions in vein carbonate and quartz associated with the suLphides are simpLe two phase inc Lusions composed of a Liquid and a smaLL gas bubbLe. The absence of daughter mineraLs indicates the soLution in the incLusion has a saLinity Less than 21 wt% NaCL equivaLent. The simpLe nature of the fLuid inc Lusions, and smaLL proportion of vapour suggest they wouLd homogenise when heated, between temperatures of apProximateLy. 200 to 300 deg C. The Lack of co-existing vapour-rich and vapour-poor fLuid incLusions means the soLutions were probabLy not boi Ling at the time of deposition. GENETIC MODELS: HydrothermaL. The form of the orebody suggests derivation from upward moving hydrothermaL fluids. MineraLisation cannot be Linked to one intrusive phase. The fact that dacite, dacite porphyry and trachyandesite are aLL mineraLised, but to varying degrees, suggests that introduction of mineraLisation was a proLonged process or 1nvoLved a number of events. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Mount Rawdon Mount Rawdon Lies near the centraL western marain of the Gympie BLock within the beLt of Late permian-Late Triassic 19neous activity. MineraLisation comprises veins and disseminations within a ?pipe-Like zone within Late Triassic pyrocLastics. REGIONAL GEOLOGY: GYMPIE BLOCK The metasedimentarY rocks of the deposit region comprise metamorphic basement (mica schist and phyLlite) overlain by steepLy dipping, Low greenschist metamorphosed fine-grained sediments and subordinate voLcanics comprisina the basaL unit of the Gympie BLock Goodnight Beds of Late Carbom ferous age. The unit is simi Lar to the host sequence at Ki Lkivan. LithoLogies indicate a deep oceanic, partLy pelagic environment of deposition. To the west the Goodnight beds are overLain by shaLLow water marine sediments of the Gympie Group. The sequence is intruded b)l Late permian-EarLy rriassic and MiddLe Triassic granitoids and overLain unconformabLy b)l an outLier of continentaL si Licic voLcanics of the Late Triassic Aranbanga beds. The principaL intrusion in the region is the MiddLe Triassic Hogback TonaLite which extends north from Mount Rawdon. LocaLLy the perry FauLt forms part of a Prominent north-northwesterLy trending Lineament marking the boundary of the Gympie BLock. The Aranbanga beds consist of up to 300 m of rhyoLitic, andesitic, and trachytic flows and pyrocLastics, some basaLt and sandstone. At Mount Rawdon the pyrocLastic sequence strikes 045 dea and dips 40-60 deg SE. The dominent rock t)lpe and main host to goLd m1neraLisation is rhyodacit1c vitric crystaL Lithic Lapi LLi tuff. The tuffs consist of a Lower commonLy weLded dacitic unit and an upper porous non-weLded rhy.odacitic unit. CLasts are very fine-grained( variabLy porphyritic ana range from rhyoLite to andesite in composit10n. Features indicate that the tuffs were probabLy deposited from subaeriaL pyroclastic flows fram a vent Less than 10 km di stant. The pyroclastics are cut by a variety of intrusives. i) The earLiest is a composite dacite porphyry, brecciated aLong its contacts with the pyrocLastics. The oLder phase, and to a Lesser extent the younger Phase, are aLtered and mineraLised, mainLy aLong the brecciated contacts. Narrow dykes emanate from the cacites and cut the pyroc Lasti cs. ii) Numerous trachyandesite dykes and a Larger subcircuLar body of

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~--MICROGRAPHICS

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trachyandesite cut the pyroclastics along sheared and brecciated margins. The dykes dip northwest at 10-50 deg towards the larger body which is weakly altered and mineralised. iii) Three east-West striking post-gold mineralisation trachyte dykes emanating from an intrusive body to the west cut most other rock types. The dykes dip north at 20-40 deg. lV) The tr21chyte dykes and dacite porphyries are cut by a younger trachyte dyke to the south. Mineralisation occurs in irregular narrow veins and disseminated through a zone of lapilli tuff, with a high density of cross-cutting dykes. The mineralised zone is oval in pLan, inverted conical in section. The lapilli tuffs host most of the disseminated mineralisation as their higher permeabi lity favoured localisation of ore solutions. The unwelded rhyodacite tuff was mineralised in preference to the welded dacite tuff. Barren calcite-pyrite veinlets also cut the tuff. REFERENCES: R.A. , Leckie J.F. , 1987 Mount Rawdon: exploration of a buLk low-grade gold deposit. IN Herbert H.K. (ed) - Gold in Queens land. proceedings of one-day symposium, University of Queens land, June 1984. University ot Queens land. Department of Geology. Papers 12(1) P85-99 Cayzer

Ellis P.L. 1968 Geo logy of the Maryborough 1: 250 000 sheet area. Geological Survey of Queensland. Report 26 Mustard H. , 1986 Geology and mineralisation of the Mount Rawdon gold prospect. IN Willmott W.F.(ed) - South Burnett district. 1986 field cenference. Geological Society of Australia. Queensland Division 1v P42-48 0000000000000000000000000000000000000000

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.---MICROGRAPHICS DEPOSIT:

32

BUREAU-----~--.-_-----------1IIIDIIII\

CRACOW

DEPOSIT IDENTIFICATION: SYNONYMS: Golden plateau, PRINCIPAL COMMOOITIES: AU , A9 , MINES: Ferneyside , Golden plateau, OREBODIES: Dawn, Excelsior , Ferneyside , Gol~cn Mi le, Golden plateau , Golden Aest , Klondyke , Lamberts surprise, Revival, Roma North, Roses pride , Whi te Hope , GROUP: BOl4en Group COMMENTS: Includes regional setting of Bowen Basin. Record covers Cracow goldfield, which comprises mostly small deposits and one major deposit, Golden Plateau, distributed over a NNW-trending belt 6km x 2km. LOCATION: LATITUDE: 25 22 250K SHEET: SGS6 5

LONGITUDE: 150 18 100K SHEET: 8947

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Eidsvold MINING FIELD: LOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD prospecti ng

DISCOVERY YEAR 1931 OPERATING STATUS AT 1987 MINE Golden plateau Ferneyside Golden plateau /olden plateau

STATUS Historical possible Operating Comp letea

MINING METHOD Unde rg round Open-Cut Open-Cut Tai lings Re-Treatment

COMPANIES:

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OREBODY: Ferneyside CO~lMENTS

PRESENT OPERATORS: Cracow Go Ld Ltd. EQUITY 12.50 50.00 37.50

PRESENT OWNERS: Cracow GoLd Ltd. costain AustraLia Ltd. Sedimentary HoLdings Ltd.

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COMMENTS

OREBODY: Go Lden pLateau COMMENTS

PRESENT OPERATORS: Crac ow Go Ld Ltd. EQUITY 12.50 50.00 37.50

PRESENT OWNERS: Cracow Go Ld Ltd. costain AustraLia Ltd. SedimentarY HoLdings Ltd.

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COMMENTS

PRODUCTION: CUMULATIVE PRODUCTION (TO DEC.1986): RECOV ERED GRADEC9 It) ORECt): GOLDCkg) 11 .74 1,578,000 1~528

COMMENTS

MAIN PRODUCTION PERIODS: 1 931-1 976 , 1 987- , RESOURCES: GRADECg/t)

GOLDC kg)

CLASSIFICATION

Sept 1987 1,500 sept 1987 1,100

5.5 4.0

8,250 4,400

Sept 1987 41

10.2

418

Economi c Infe rred Economic Demonstrated - Measured Sub-Econom i c DemonS t rated Sub-Economic Inferred

ORE C'OOOt)

DATE

Sept 1987 250

3.0

750

In-Situ RecoverabLe

o/c o/c

In-Situ

o/e

Go Lden pLateau, to 61m Fe rneys i de

In-Situ

o/c

Fe rneys i de

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE:

BLOCK: PROV INCE: SUB-PROVINCE: B014en Basin HOST ROCKS: camboon Andesite Andesite, dacite, trachyte, rhyoLite fLows and pyrocLastics, minor sediments.

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....--MICROGRAPHICS

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Mineralisation consisted of mostly steeply dipping Lodes in veins, fissures, and breccia zones.

fault-controlled

siliceous

Rhyo lite dyke. Intrudes mineralised andesite; is spatially cLosely related to some ore shoots. AGE: palaeozoic Early permian S TRUC TURAL FEATURES MAJOR: Faulting, Fracturing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS SIGNIFICANT: Fault/Fault, IGNEOUS PROXIMITY MAJOR: Volcanism(Intermediate) , SIGNIFICANT: Sub-Volcanisnl(Felsic porphyry) , AGE OF INTRUSION: palaeozoic Late Carboni ferous METAMORPHISM: Greenschist facies. ALTERATION: Mineralisation in the larger deposits of the field is accompanied by strong hydrothermal alteration. The breccia fragments are propylitised or siLicified andesite, comprising adularia (after K-feldspar phenoc rysts), kao l in, ch lori te, pyrite, epidote, ca lc i te, zeo lite. The andesite fragments are altereCl by progressive rim-silicification which produced the concentric crust microstructure of the lode breccia. The alteration sequence was evidently hematisation (ferro-chlorite), argi llisation (kaolin), si licification. Country rocks show varying, locally intense, degrees of hYdrothermal alteration. Chloritisation is welL developed in the volcanics adjacent to the lodes. DEPOSIT CHARACTERISTICS:

-----------------------TYPES: Lode in intermediate volcanics adjacent to felsic/intermediate porphyry intrusive. STYLE: Discordant , stratabound , MORPHOLOGY: Irregular, Tabular, AGE OF MINERALISATION: palaeozoic Early permian DIMENS IONS: OREBODY: Golden Plateau STRIKE LENGTH TRUE IHDTH VERTICAL DEPTH DEPTH OXIDATION

n-

m

MIN

AVE

m m

m

30.0

~lAX

700.0 15.0 250.0

[ji]-AGPS--...

.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - -.... NATURE OF MINERALISATION: Disseminated, Free Mi LLing , Oxidised, primary, PRIMARY ORE: Breccia , Vein (Reef) , MINERALOGY: OREBODY: GoLden PLateau suLphide zone: goLd, guartz, aduLaria, sphaLerite, chaLcopyrite, gaLena, bornite( hess1te, trace aLtaite, arsenopyrite, ?argentite. SU Lphi aes cons t1 tute on Ly about 1 r. of tota L roc k. Go Ld oc curs in the form of goLd-silver alloy as in the form of fineLy-divided disseminations up to 10 microns grainsize, and as composite grains and inter~rowths associated with suLphides. paragenetic sequence of the main suLph1des was: fi rst pyrite, foLLowed in order by sphaLerite, chaLopyrite, ~aLena, contemporaneousLy with goLd-hessite intergrowth. GoLd content 1S negativeLy reLated to chaLcopy,"ite abundance. GoLdsuLphides are associated with concentric crusts of quartz-K-feLdspar (aduLaria)-carbonate around nucLeii of breccia fragments of aLtered andesite. Gold is indicated by aduLaria and by wavy or concentric banding in the quartz. Oxide zone: goLd (strongLy enriched reLative to sulphide zone), quartz, Limonite, hematite, carbonate. Gold occurs mainLy as "paint" or GENETIC CONTROLS: Disposition of Lodes and LocaLisation of oreshoots are both strong Ly structuralL)f controLLed but the exact reLationship is compLex. Ransom & Knight (1975) determined that the majority of oreshoots pLunge paraLLeL to the axis of the cyLindroidaL totaL fauLt surface. Some oreshoots are controLLed by rhyoLite dykes. The paucity of mineraLisation in the bounaing north-northwest fauLts may be attributabLe to their possibLe compressionaL nature contrasted with the tensionaL nature of the ore controlling fauLts. Oxygen isotope data (Gold1ng & others, 1987) indicate an epithermaL meteoric ore-fLuid source. GENETIC MODELS: The GoLden pLateau orebody is a typical epithermaL vein system. Brooks (1965) and Buley (1953) favoured a hydrotherma l rep Lacement mode L in ~,hich mineraLisation was introduced in association with rhyoLite dyke empLacement, which was assi~ned a Late permidn to Late Triassic age. However, more recent invest1~ations [Ransom & Knight (1975), Mar Low (1983)] favour a voLcanic or1gin in which the orebody Lies on the northern margin of a volcanic centre, the caLdera boundary coinciding with the 'South WaLL', and mineraLisation was introduced contemporaneousLy witn voLcanism. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: GoLden PLateau The Cracow "oLdfieLd Lies on the southeastern margin of the Bowen Basin, within massive andesitic voLcanics which form the basaL unit of the basin seguence. The Golden PLateau was by far the largest Lode system of the f1 e Ld. REGIONAL SETTING: BOWEN BASIN The Bowen Basin is a Large region of Permian and Triassic deposition between the earLy paLaeozoic Thomson Fold Belt (represented by the Lol~,orth-Ravenswood Block and Anakie Inlier) and the Late PalaeozoicMesozoic New England Fold BeLt. The basin deveLoped in the Early permian as a probable foreland basin along a pacific-type continentaL margin. The Australian continent (represented by the Anakie Inlier) Lay to the west and a calc-alkaline volcanic arc - the Camboon Arc -

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...---MICROGRAPHICS

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BUREAU------~-------------

deveLoped over the site of the earlier connors-Auburn VoLcanic Arc to the east. ALong the western margin of the arc the voLcanics form a wedge up to 3000 m thick that dil:Js beneath younger continentaL (incLuding coaL) and shaLLow marine basin strata. The voLcanics - mostLy camboon Andesite - unconformabLy overLie EarLy Carboni ferous fe Lsic voLcanics (TorsdaLe Beds) of the Auburn Arch, which are intruded by Late carboniferous granitoids. The eastern part of the arch is made up of permo-Triassic bathoLiths. ASSOCIATED MINERALISATION The Cracow and Clermont (Deposit No. 27) goLd deposits are the onLy known metaLLiferous deposits of the basin sequence. GEOLOGICAL SETTING: CRACO~I The Camboon Andesite consists of andesitic and basaLtic fLows, andesitic to dacitic weLded tuff, agglomerate, voLcanic breccia, congLomerate, subordinate sandstone, mUdstone. rne interbedded I"arine sediments are more abundant upsequence. The envHonment of depo~ition of the volcanics was partLy subaeriaL, l:Jartly subaqueous. The volcanics are unconformabLy overlain by thin limestone units and then thick cLastic shaLLow marine and fresh water sediments (Back Creek Group). RegionaL strike of the basin sequence is north-northwest, dip 25 deg ~,est.

The Cracow goldfieLd consisted of a number of fault-controLLed quartz Lode systems (quartz-caLcite-feldspar-zeolite) in andesite, of which the most productive was GoLden Plateau. The host voLcanics are intruded by smalL bosses of gabbro-diorite-andesite and by Late-stage porphyritic rhyoLite-dacite-trachyte dykes, both of possibLe Late Permian affi liation. The host stratigral:Jhy at GoLden plateau represents interlayering of subaqueously deposited trachyte-trachyandesite Lava fLows with subaerialLy deposited pyroclastic rocks of similar composition. A basal unit of feLsic tufts, flows and breccias is overlain by andesitic tufts, fragmentaLs and fLows, and an upper sequence of feLsic flows and tuffs. MineraLisation occurs preferentiaLLy in andesite flows. GoLden PLateau consists of a structuraLLy compLex anastomosing series of auriferous quartz-fi LLed veins, fissures and breccia zones, forming a sinuous east-west trending faulted and denseLy fractured crOSS link betl4een 2 poorLy mineraLised north-northwesterLy trending fauLt zones. Oreshoots occur discontinuousLy aLong the lode system, strikinQ paraLLeL or subparaLLe L to the Lode system. Dil:Js are highly variabLe" ln the east oreshoots are steep to verticaL, in the west dips are shaLLower at 40-75 deg south. The breccia zones are Qenera LLy adj acent to fauLt or joint p Lanes with mineralisation decreaslng away from the structural pLane. oreshoots at the eastern end of the orebody are commonly adjacent to rhyolite dykes. The breccia comprise cLasts of randomLysorted, angular, siLicified and/or kaoLinised andesite in a matrix of vein-type to drusy quartz +- admixed ferruginous carbonate. Both curved and planar fauLts occur in the orebody. Ransom & Knight (1975) related the fauLt orientations to two totaL structural surfaces: i) a cyLindroidaL surface pLunging 70-80 deg 14, and iD a conicaL surface with simi Lar pLunge and apicaL angLe of 80 deg. The mineraLisation was apparentLy best deveLoped aLong an arcuate, south-dipping fauLt ZOlle, the South WaLl.

REFERENCES: Bonner M. H. (1952 The' KLondyke goLd mine - Cracow. QueensLand Government Mining JournaL 53 p57-60

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[ji]-AGPS--'"

.---M ICR OGR APH ICS B U R E A U - --------=------

---..

Brooks J .H. , 1959 GoLden pLateau mine, Cracow. Report of geoLogi caL inspect ion, 23rd JuLy to 10th August, 1958. Queens Land Governm ent Mini ng JournaL 60 p617-62 5 Brooks J .H. , 1959 Inspect ion of GoLden PLateau mine, Cracow, 1959. Queens Land Governm ent Mini ng J ourna L 60 P774-77 8 Brooks J .H. , 1965 GoLd deposit of GoLden pLateau . IN McAndrew J .(ed) - GeoLogy of AustraL ian ore deposit s. 8th commonweaLth Mining congres s, AustraL ia & New zeaLand , 1965, MeLbour ne.& MetaLLu rgicaL AusIMM 1 P361-36 4 Brooks J .H. , 1969 ExpLora tion and geoLogy of the Ns8 ore shoot, GoLden pLateau mine, cracow, Queens Land. QueensL and Governm ent Mining JournaL 70 p537-54 2 Brooks J.H. , 1974 Departm entaL diamond driLLing program - Cracow goLdfie Ld. GeoLogi caL Survey of QueensL and. Report 81 BuLey J .V. , 1953 Cracow goLdfie Ld. IN Edwards A.B.(ed ) - GeoLogy of AustraL ian ore deposit s. 5th Empire Mining & MetaLLu rgicaL congres s, AustraL ia & New zeaLand , 1953, MeLbour ne. AusIMM 1v p817-82 2 Campbe LL F.A. , 1955 Report on GoLden pLateau NL, Cracow, QLd. GoLden pLateau NL. UnpubLi shed Report 1v Denmead A.K. , 1976 The GoLden pLateau - 1931 to 1976. Queens Land Governm ent Mi ni ng J ourna L LXXVII( 894) P136-141 Denmead A. K. , 1933 Recent deveLop ment at Cracow. Parts 1 and 2. QueensL and Governm ent Mining JournaL 34 p196-19 9; p237-23 9 Denmead A.K. , 1937 Cracow ore reserve s. parts I, Il, Ill. QueensL and Governm ent Mining JournaL 38 p121-12 5; p156-15 9; P191-19 4 Denmead A.K. , 1938 ExceLsi or and Ferneys ide G.M.L. 's, cracow. QueensL and Governm ent Mining JournaL 39 p263-26 5

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BIIJIlID---MICROGRAPHICS BURE AU - - - - - - - -...- - - - - - -

-... .

Denmead A.K. , The Cracow goLd 1938 fieLd - a preLimi nary report on the present positio n. Queens Land Governm ent Mi ni ng J ourna L 39 P262-26 3 Denmead A.K. , 1938 The cracow goLd fieLd. Parts I-Ill. QueensL and Governm ent Mining JournaL 39 P335-40 iP262-5 i p368-76 i p406-12 Denmead A.K. , 1939 The Cracow goLd fieLd. part IV. Queens Land Governm ent Mi ni ng J ourna L 40 p14 Denmead A.K. , 1946 Notes on Cracow goLd fieLd. QueensL and Governm ent Mining JournaL 47 p306-311 GoLding S.D. , WiLson A.F. , Scott M. , Anderso n P.K. , Waring C.L. , FLitcro ft M. , Rypkema H.A. , 1987 Isotopic evidenc e for the diverse origins of goLd in Queens Land. IN Herbert H.K. (ed) - GoLd in Queens Land. proceed ings of one-day symposiu m, univers ity of QueensL and, June 198/~. univers ity of QueensL and. Departm ent of GeoLogy . papers 12 (1) P65-83 KayJ.R . ,1983 A review of meta LLi ferous mineral isation associa ted with Permian rocks in QueensL and. IN Permian geoLogy of QueensL and. proceed ings of symposiu m, Brisban e, JuLy 1982. GeoLogi caL Society of AustraL ia. Queensl and Divisio n 1v p343-35 2 Knight J .A. , 1971 A structur aL interpr etation of the Cracow fieLd. GoLden pLateau NL. Unpubli shed Report 1v Ma r Low N. G• , 1 983 The GoLden pLateau Mine, Cracow. IN Waterho use J.B.(ed ) - 1983 fieLd confere nce. Permian of the si LoeLa Moura-C racow area, 11-13 June 1983. GeoLogi caL Society of Austral ia. Queensl and Divisio n 1v p75-93 Mc Dona Ld J. A. , 1 965 GoLd-s ilver ore from the GoLden pLateau N.L. mine, Queensl and. CSIRO. Minerag raphic Investi gations . Report 906 Ransom D.M. , Knight J.A. , 1975 GoLden pLateau goLd Lodes. IN Knight C.L.(ed ) - Economi c geoLogy of AustraL ia and Papua New Guinea - 1. MetaLs. AusIMM. Monogra ph Series 5 P773-77 9 Reid J .H. , 1931 The Cracow goLd deposit s. QueensL and Governm ent Mining JournaL

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32 P473-476 stiLLHeLL F.L. , 1937 Ore sampL~s from Go~den PLateau, CracoW, QLd. CSIRO. Mlneragraphlc Report 116 ~Ihitaker W.G. , Murphy P.R. 6 RoLLason R.G. , 1974 GeoLogy of the Mundubbera 1:25 000 sheet area. GeoLogicaL Survey of QueensLand. Report 84 00000000000000000000000000000000000 0 0000

ta-

***

M14

***

[1N-AGPS _ _1IiII

....--MICROGRAPHICS BUREAU-----...------------~ DEPO: IT:

33

EIDSVOLD

DEPOS,T IDENTIFICATION:

----- ._---------------

PRINCiPAL COMMODITIES: AU , Ag , MINES: Ei dsvo ld , OREBODIES: Craven, Eidsvold , Lady Augusta (Stockman) , Maid Of Erin , Mount Rose, GROUP: permo-Tr;assic Igneous Group COMMENTS: Inc ludes regional setting of Gogango overfolded zone. see Deposit No. 35 Gympie for regional setting of New EnglanCl Fold Belt; Deposit 34 Ki lkivan for setting of Permo-Triassic igneous group. lOCATION: LA TITUDE: 25 21 250K SHEET: SG56 5

LONG ITUDE: 151 6 100K SHEET: 9147

ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Eidsvold MINING FIELD: lOCALITY: DEVELOPMENT HISTORY: DISCOVERY METHOD P rospec t i ng P rospec ti ng

DISCOVERY YEAR 1858 1886 OPERATING STATUS AT 1987 MINE Eidsvold

MINING METHOD Unde rg round

STATUS Historical

COMPANIES: PRODUCTION: CUMULATIVE PRODUCTION (TO DEC.1986):

~...

***

N14

***

- - - - - - - - - - - - -.. [li]]-AGPS _ _d

.---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - - -1II ORECt): 90,025

GOLD(kg) 3,012

RECOVERED GRADEC9/t) 33.45

COMMENTS

MAIN PRODUCTION PERIODS: 1887-1914 , RESOURCES: PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman FoLd BeLt PROV INCE: New Eng Land Orogen SUB-PROV INC E: Gogango overfo Lded zone HOST ROCKS: Ei dsvo Ld Comp Le x Leucocratic biotite granite, hornbLende-biotite granodiorite, gabbro. MineraLisation occurred in quartz reefs.

hornbLende

Nogo Beds Andesitic to basaLtic voLcanics, arenite, sLate, chert, congLomerate. Country rock to mineraLised granitoid intrusive. Host to very minor mi nera Lisation.

quartz

vein

AGE: Mesozoic EarLy Triassic AGE: PaLaeozoic Late permian STRUCTURAL FEATURES STRUCTURAL/STRATIGRAPHIC INTERSECTIONS IGNEOUS PROXIMITY MAJOR: P LutonismCGrani te) , AGE OF INTRUSION: Mesozoic EarLy Triassic AGE OF INTRUSION: PaLaeozoic Late permiar METAMORPHISM: Nogo Beds are hornfeLsed to hornbLende-hornfeLs facies. ALTERATION: Mineralisation is associated with hydrothermal aLteration kaolinisation of feLdspars up to severaL metres from reef contacts.

=

DEPOSIT CHARACTERISTICS:

------------------------

...

***

A15

***

- - - - - - ~... AGPS--..

l!IIlIIlIII---MICROGRAPHICS B U R E A U - - - - - - - - - & - . - - -....- - - -..... TYPES: Auriferous quartz veins in granitoid. Auriferous quartz veins in metasediments adjacent to granitoid. STYLE: Discordant , stratabound , AGE OF MINERALISATION: Mesozoic Early Triassic AGE OF MINERALISATION: palaeozoic Late permian o I MENS IONS: OREBODY: Craven TRUE WIDTH ( cm ) OREBODY: Lady Augusta (stoc kman) VERTICAL DEPTH TRUE WIDTH OREBODY: Maid of Erin

m ) cm )

TRUE WIDTH OREBODY: Mount Rose

cm

TRUE WIDTH

MIN

AVE 20.0

MAX

MIN

AVE

MAX 247.0 20.0

9.0 MIN

AVE 120.0

MAX

MIN

AVE 75.0

MAX

cm

NATURE OF MINERALISATION: PRIMARY ORE: Vein (Reef) , MINERALOGY: OREBODY: Eidsvold sulphide zone: gold, minor pyrite, chalcopyrite, and sphalerite (Maid of Erin ), stibnite and cassiterite (Stockman), 9alena (All Nations), molybdenite (Moonlight), and arsenopyrlte. Gangue: quartz, c lay, calcite. GENETIC CONTROLS: controls are structural - reefs are aligned parallel to regional structural trends - and lithological - reefs are mostly contained within granitoid intrusive complex. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Eidsvold Eidsvold is hosted by Late permian-Early Triassic granites at the southeastern margin of the Gogango Overfoldei:l Zone. REGIONAL SETTING: GOGANGO OVERFOLDED ZONE The Gogango Overfolded Zone contains thick sequences of fine-grained flysch-type sediments and ocean floor basaltic and andesitic volcanics. The volcanic/Volcanic lastic sequence accumulated in an elongate deep mari ne trough (Grant leigh Trou9h) flanki ng a vo lcani c arc (Camboon Volcanic Arc) on its eastern slde. The Camboon Arc developed ;n the Early Permian over the site of the earlier connors-Auburn Arc (See Deposit No. 35 Gympie). The Grantleigh Trough may bave been the site of incipient rifti(lg to form a marginal sea or alternatively it may have formed as a pull-apart basin by' major transcurrent faulting. The basin sequence was deformed in the Middle permian to form the Go,;ango Overfolded Zone. The southern part of the zone was one of the principal sites of intrusion of Late permian-Early Triassic granitoid batholiths.

_AGPS-.-w'"

..---MICROGRAPHIeS

BUREAU--~---------------IIIIIIII\!II

The composite RawbeLLe BathoLith is exposed in a meridionaLLy eLongate be lt over much of the southern part of the zone, intrudinll carboni ferous granitic rocks of the Auburn Arch to the west, and obscunng the margin of the zone in the east. The permian voLcano-sedimentary sequence is represented in the Eidsvold region by a series of andesitic to basaLtic Lavas and tuffs and Largely volcanogenic sediments - Labile arenite, sLate f chert, congLomerate (Nogo Beds( Narayen Beds). The sequence is fOLded along northerLy axes and hornfe sed as a resuLt of permo-Triassic granite intrusion. The Rawbe Lle BathoLith is a comp'osite intrusion of at Least 8 phases, which was empLaced during a series of intrusive events throughout the Late Permian and EarLy Triassic. The rocks range in composition from gabbr o to granite, with the dominant types being biotite-hornbLende granodiorite, and hornbLede-biotite adameLlite. GoLd mineraLisation is associated with the gabbroic phases. The Eidsvold compLex is a smalL discrete meridionalLy elongate igneous compLex of L.ate permian-EarLy Triassic age which intrudes Nogo Beds severaL ki lometres east of the main contact with the RawbeLLe sathoLith. lithoLogies are Leucocratic bi"tite granite, hornbLende-biotite granodiorite, hornbLende quartz gabbro. ASSOCIATED MINERALISATION Widespread but mostLy minor goLd mineraLisation is associated with various p.hases of the RawbeLLe BathoLith and associated intrusions mainLY EidsvoLd compLex, host to mineraLisation at EidsvoLd. The reefs occur in the Less feLsic phases, which may represent the oLder parts of the batholith, or in adjacent hornfeLsed country rocks spatiaLLy reLated to fe ls i c to i nte rmedi ate dy kes. At EidsvoLd, gold mineraLisation occurs in quartz reefs in the southern tip of the EidsvoLd CompLex; isoLated reefs occur in adjacent hornfeLsed sediments and voLcanics of the Nogo Beds. REFERENCES: Cameron W.E. ,1910 Burnett gold mines property at EidsvoLd. Queens Land Government Mi ni ng Journa L 11 p284-285 Cribb H.G.S. ,1936 Lady Augusta mine, EidsvoLd. QueensLand Government Mining JournaL XXXVII(43S) P267-268 Rands W.H. , 1901 EidsvoLd goLa field, with notes ')n Mckonkey's creek diggings and antimony Lode. Queens Land Government Mi ni ng Journa L 2 p304-308 Siemon J .E. , Green P.M. , Horton D.J. , 1977 Some mines and mineraL deposits of the Gayndah-Biggenden area. IN Day R.W.(ed) - 1977 field conference, Lady ELLiot IS Land-Fraser IslandGayndah-Biggenden. GeologicaL Society of A~straLia. QueensLand Division 1v p79-86 Whitaker W.G. , MUrphY P.R. 6 RoLlason R.G. , 1974 GeoLogy' of the Mundubbera 1 :25 000 sheet area. Geo logica L Survey of Queens Land. Report

....

**1t C15

..-a

,~**

..

~-AGPS--

.---ltUCROGRAPHICS

BUREAU------~------------t

84 0000000000000000000000000000000000000000

e-.

- - - - [ i i i ] - A G P S - -..

pIIIlI--MICROGRAPHICS BUREAU

DEPOSIT:

34

- ' 1_ _. . . ._ _- - - -. . . . .

KILKIVAN

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: AU , Cu , Hg , MINES: Ki Lkivan , Shamrock, OREBODIES: GoLd Top, Ki Lkivan , Long TunneL, Rise And shine, Shamrock, Tansey , GROUP: permo-Triassic Igneous Group COMMENTS: Inc Ludes regionaL setting of premo-Triassic igneous !;lroup and of North d' AguiLar group. See Deposit NO. 35 Gympie for regionaL settlng of New EngLand FoLd BeLt. LOCATION: LONGITUDE: 152 14 100K SHEET: 9345

LATITUDE: 26 4 250K SHEET: SG56 10 ADMINISTRATIVE SUBDIV ISION: MINING DISTICT: Gympie MINING FIELD: LOCALITY: DEV ELOPMENT HISTORY:

DISCOVERY METHOD prospecting prospecting

DISCOVERY YEAR 1852 1867 OPERATING STATUS AT 1987 MINE Ki Lkivan Shamrock Ki lkivan

STATUS Historical Possible Operati ng

MINING METHOD unde rg round Ol:len-Cut ALLuv i a L

COMPANIES: OREBODY: KiLkivan COMMENTS

PRESENT OPERATORS: Centamin Ltd. EQUITY :t.

PRESENT OWNERS:

1.aI_ _~

~

COMMENTS

***

E15 *1,*

llii]-AGPS--..

....-- MIC ROG RAP HIC S B U R E A U - - --------------Centami n Ltd. OREBODY: Shamroc k

---.

50.00

PRESENT OPERATORS: Uni ted Reefs N L.

CONMENTS

PRESENT OI~NERS: Uni ted Reefs N L.

EQUITY 100.00

r.

CONMENTS

PRODUCTION: CUMULATIVE PRODUCiION (TO DEC.198 6): ORECt): GOLDCkg) RECOVERED GRADEC9/t) 639 0.00

COMMENTS Ore tonnage not avai LabLe. Zero figures resuLt from program caLcuLa tions.

MAIN PRODUCTION PERIODS: 1874-18 92 , 1931-19 45 , 1987, RESOURCES: DATE

OREC'OOOt)

GRADEC9/t)

GOLDCkg)

Dc" 1987

1,200

0.5

600

Dec 1987

1 ,000

3.7

3,700

CLASSIFICATION Economi c Demons trated Recovera bLe - Indi c ated Economic Demons trated In-situ - Indicate d

aLv o/c

Ki Lkivan. units are: OREC'OOO cubic rn) GRADE(9/cubic m) sham roe k. tl 11

11

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman FoLd Be Lt PROV INCE: New Eng Land oro~en SUB-PROVINCE: North D' AgU1 Lar BLock HOST ROcKS: Quartz syenite- monzon ite porphyr y. NineraL isation ;s adjacen t to or within porphyr y stocks and dykes. station Creek AdameLLite Leucocr atic hornbLe nde-bio t;te adameLL ite. Intrudes deposit area and may be genetica LLy reLated to mineraL ised i nt rus ives. Se rpenti n; te. Deposit area; s spatia Lly re Lated to serpent ; ni te be Lts ?=pr;ma ry Least some goLd minera Lisation •

....

....

source

porphyr y of

at

Mi~

... AG PS- -..

.---MICROGRAPHIeS B U R E A U - - - - - - - - - - - - - - - - - - -..... Neara VoLcanics Andesitic and rhyoLitic voLcanics, congLomerate. sUbordinate host to vein mineraLisation associated with porphyry intrusives. 'Unnamed Metamorp hi cs I Phy LLite, sLate, g reenstone. Main host to mineraLisation, in veins in fissure, shear, and fauLt zones adjacent to or within porphyry intrusives. AGE: paLaeozoic carboniferous AGE: paLaeozoic EarLy Permian STRUCTURAL FEATURES SIGNIFICANT: FauLting, Shearing, STRUCTURAL/STRATIGRAPHIC INTERSEc nONS MAJOR: Intrusive contact, IGNEOUS PROXIMITY ~lAJOR: Sub-VoLcanism(FeLsic porphyrY) , Sub-VoLcanism(Intermediate) , SIGNIFICANT: pLutonismCGranite) , VoLcanismCIntermediate) AGE OF INTRUSION: Mesozoic Triassic AGE OF INTRUSION: pa Laeozoic Carboni ferous METAMORPHISM: RegionaL metamorphic grade is greenschist fades, facies in deposit area.

Locally amphiboLite

ALTERA nON: OREBOoY: KiLkivan MineraLisation is associated with varyin~ degrees of hydrothermaL aLteration si Uciflcation, chLoritisatlon, pyritisation, edidotisation, carbonation, propyLitisation. OREBOoY: Shamrock MineraLisation is associated with h)ldrothermaL aLteration. The metamorphics are chLoritised and epidotised. The quartz diorite porphyry is pervasiveLy aLtered to quartzca rbonate-kao Lin assembLage. OREBOoY: Rise and Shine Host metamorphics are si Licified. OREBODY: Go Ld ToP The quartz syenite is weakLy aLtered, but the host andesite is more strong Ly p ropY Li ti sed and pyri ti sed.

=

DEPOSIT CHARACTERISTICS:

-----------------------TYPES: Auri ferous quartz veins in metasediments adj acent to fe Lsic/intermedia te porp'hyry intrusive • . Aun ferous quartz Velns in fe Lsic/intermediate porphyry intrusive. STYLE: Discordant, stratabound ,

i1aEmI

IIIIIIlIIIiI~

***

G15 >~**

....

....

[AillJ .. AGPS - _...

llJIIII IIIIl-- MICR OGR APHI CS B U R E A U - -------------MORPHOLOGY: Boomer ang-Sha ped, AGE OF MINERALISATION: Mesozoic Triassic DIMENSIONS: OREBODY: GoLd TOP MIN ( m ) STRIKE LENGTH ( cm ) 1S.o TRUE WIDTH ( m) VERTICAL DEPTH DEPTH OXIDATION ( m ) OREBODY: Rise And Shine MIN DEPTH OXIDATION (m OREBODY: Shamroc k STRIKE LENGTH VERTICAL DEPTH

m m

AVE

12.0

----

MAX So.o 100.0 20.0

AVE 20.0

MAX

AVE

MflX 1 So.O 100.0

NATURE OF MINERALISATION: Free Mi LLing , oxidise d, primar y, Refract ory PRIMARY ORE: Vein (Reef) , sECONDARY ORE: DetritaL (ALLuvi aL) , MINERALOGY: OREBODY: GO Ld Top SuLphid e zone: goLd, pyrite, stibnit e, chaLcop yrite, gaLena, spha Lerite, tetrahe drite. Gangue: quartz, tourmaL ine, carbona te. The veins are anomaLo us in mercury . OREBODY: Ki Lkivan SuLphid e zone: goLd, chaLcop yrite, lJyrite, variabL e stibnit e, gaLena, sphaLe rite, arsenop yrite, tetrahe drite. Gangue: quartz, caLcite , +-magn etite, hematit e, tourmaL ine, chLorit e, mangane se oxides. OREBODY: Rise And Shine SuLphid e zone: goLd, gaLena, sphaLe rite, pyrite, arsenop yrite. Gangue: quartz, calcite . The veins are anomaLo us in mercury . OREBODY: Shamroc k SuLphid e zone: quartz, carbona te, pyrite, chaLcop yrite, magnet ite, spha Leri te, tourma Line. GENETIC CONTROLS: controL s are structur aL and LithoLo gicaL. structur aL - many of the deposit s are Located on major north northw est-stri king zones of structur aL weaknes s, and vein trends to paraLLe L regionaL structur aL trends. LithoLo gicaL - deposit s are concent rated in metamor phic rocks cLose to Late Carboni ferous serpent inite bodies. The mineraL isation is closeLy spatiaLL y reLated to Triassic porphy ritic intrusiv e bodies of feLsic to interme diate compos Oxygen isotope data ition. (GoLding & others, 1987) indicate a magmati chydrothe rmaL ore-flu id source. GENETIC MODELS: EarLier studies (Jones, 1948; Warren, 1972) reLated mineraL isation to intrusio n of serpent inite. Brooks & (1974) and Bischof f (1986) conside r the mineraL isation to be of others hypother maL to mesother maL origin genetica LLy re Lated to the rriassic porphyr y intrusiv es. Brooks

**1,

H1 S

***

-AG PS --... .

ptII-- MICROGRAPHIeS BUREAU - - - - - - - - - - - - - - . . - - - - - - - . identified a minor EarLy Triassic mineraLising episode reLated to diorite and fe Lsic to intermediate dykes, and a major MiddLe-Late Triassic episode re~ted to fe~ic porphyry, LocaLLy andesite. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Go Ld ToP Two siLiceous, pyritic crush reefs occupied sub-paraLLeL fissures about 30 m apart in Lati te and trachyte of the Neara VoLcanics. The reefs are adjacent to the southeast bounClary of a ring-Like quartz syenite porphYI·y intrusive. OREBODY: Ki Lkivan Ki Lkivan is hosted by metamorphic rocks in the northern part of the North d' Agui Lar BLock, in contact with voLcanics of the Esk Trough to the west and Low-Qrade metasediments of the Gympie BLock to the east. A diversity of veln type mineraLisation occurs. REGIONAL GEOLOGY: PERMO-TRIASSIC IGNEOUS PROVINCE From Late permian-Late Triassic, aLL bLocks of the New EngLand Orogen were emergent, except the Gympie Basin. The southern part of the orogen ~'as upLifted and extensiveLy intruded by granite bathoLiths of the southeast QueensLand pLutonic province. permo-Triassic granites are most abundant in the Gympie and Yarraman BLocks and the Gogango OverfoLded Zone. post-orogenic voLcanics were concentrated in the Esk and Abercorn Troughs between the zones of pLutonism; younger voLcanics were erupted in the Gympie Basin foLLowing the cLose of sedimentation. ASSOCIATED MINERALISATION Numerous, generaLLy smaLL but rich goLd vein and breccia-pipe deposits are associated with the permo-Triassic igneous province (EidsvoLd, Mount Cannindah, Ki Lkivan, AgricoLa, Mount Rawdon). HistoricaL production came mainLy from quartz-caLcite-suLphide reefs fi Lling fissures or joints in granitic intrusives or in the adjacent sedimentary/voLcanic rocks (KiLkivan, EidsvoLd). Deposits were commonLy associated with silicic to intermediate dykes. MineraLisation is preferentially Located in the earLier more mafic phases of composite intrusions. Low grade disseminated deposits are associated with the voLcanics (Mount Rawdon), and QoLd is aLso associated with porphyry copper deposits (Mount Cannlndah), which are a feature of the Permo-Triassic igneous province. REGIONAL GEOLOGY: NORTH D'AGUILAR BLOCK The metamorphic sequence ('Unnamed metamorphics', Day & others, 1983) comprise fine-grained metasediments and mafic metavoLcanics of Carboniferous-EarLy permian age. LithoLoQies are indicative of deposition in a deep ocenic, partLy peLaglc environment. The rocks may represent younger sediments of the mainLy Devono-Carboniferous Wandi LLa S Lope and Basin or aLternativeLy were deposited in a di fferent tectonic envi ronment and subsequent Ly transported to thei r present posi tion. The bLock probabLy formed the western margin of the depositionaL basin of the Gympie BLock Carboniferous-Triassic succession. The WandiLLa SLope and Basin (see Deposit No. 35 Gympie) was a continentaL sLope/oceanic basin depositionaL zone which Lay east of a voLcanic arc/marine sheLf (forearc basin) in the Devonian and Carboniferous. The Wandi Lla sequence was deformed at the end of the Carboniferous and is nOl4 preserved in the CoastaL, Yarranan, south d'Aguilar and BeenLeigh BLocks. The North d'Aguilar sequence was aLso deformed in the Late Carboniferous but is younger than the WandiLla sequence. If the North d' Agui Lar BLock represents Wandi LLa deposits, the sLope/basin system must have extended further east with time. REGIONAL SETTING: PERMO-TRIASSIC IGNEOUS GROUP The North d'AguiLar metamorphosed voLcano-sedimentary sequence was fauLted, foLded and re~ionaLLy metamorphosed to the greenschist, amphiboLite, and transltionaL bLueschist facies at the end of tne Carboniferous. In the northern part of bLock, serpentinite masses were

...

...

~-AGPS--

~--MICROGRAPHICS

BUREAU---------------------.

emplaced adjacent to fault zones along the eastern boundary, and small synorogenic granodiorite pLutons were emplaced alon!j the western margin. The North d' Agui lar BLock was affected by Late Permlan-Late Triassic post-orogenic igneous activity. ASSOCIATED MINERALISATION Minor nickel, cobaLt, manganese, etc deposits are associated with serpentinite. The principal mineralisation at Ki lkivan comprises numerous but smalL epigenetic hydrothermal deposits of mercury, gold, si lver, base metaLs, antimony and molybdenum in vein systems, oreccia zones and alteration zones related to Triassic granitoid and porphyry i ntrus ives. GEOLOGICAL SETTING: KILKIVAN The metamorphic rocks consist mainly of greenschist facies phyllite, schist and greenstone, plus minor limestone, slate, mudstone, chert, jasper, amphiboLite, granofels, argillite, arkose and andesite. In the Ki lkivan area, metamorphic grade is amphioolite facies adj accnt to a Carboniferous granodiorite pLuton (Claddagh Granodiorite) in the western part of the deposit area. The metamorphics are foLded and faulted along north~'est-trendin!j axes. Foliation and bedding are both steep ly-dipping and northwest-strlking. shear zones up to 300 m wide occur in the unit. Massive serpentinite and serpentinite breccia extend in a discontinuous northerly trending belt through the eastern part of the deposit area. Larger masses occur adjacent to fault zones southeast of Ki lkivan. The metamorphic sequence is over lain by an outLier of Early-Middle Triassic Neara Volcanics in the southeastern part of the deposit area. The main depositional area of the volcanics was the Esk Trough to the west. In the Ki lkivan area, the unit is represented by porphyritic andesitic and rhyoLitic volcanics, oligomictic conglomerate, and coarse ash-lapi II i tuffs. Both the permo-Carboniferous metamorphic rocks and the volcanics are intruded in the eastern part of the deposit area by a large irregular EarLy-MiddLe Triassic bathoLith, the Station Creek Adamellite, which extends east into the Gympie Block. The dominant rock type is leucocratic hornbLende-biotite adamelLite, with marginaL diorite, grani te, and monzonite phases. The area is aLso intruded by Triassic syenite-monzonite porphyry dykes and stocks. Gold mineraLisation is almost exclusively associated with the rriassic porphyry intrusives. The ma/,"orit y of deposits are veins in fissure, shear and fault zones. Bisc off (1986) distinguishes 4 categories, based on host-rock associations:i) Porphyry stock-hosted deposits are typicaLLy AU+Cu+-Ag-bearing veins surrounded by thin aLteration envelopes, within the porphyry intrusive (e.g. some in BLack Snake area, incLuding Shamrock; yorkeys area; Jimmy Scrub area). ii) Porphyry stock-associated deposits occur within countrY rock adjacent to porphyry intrusives (e.g. some BLack Snake, possibly GoLd T9P. »• Dye-re k l ate d d " " t 0 f velns " "h ln, " " L an d 111 eposlts consls Wlt or marglna paraLlel to quartz-syenite dykes (e.g. Long TunneL, Rise and Shine, South Burnett). iv) Shear zone-hosted deposits in metamorphics (e.g. Lord Nelson). OREBODY: Lo ng Tunne l ~lineraLisation was localised in smalL veins in a zone of intense jointing within and along the contacts of faulted pyritic trachyte and diorite dykes intruding the sheared metamorphic sequence. The trachyte dyke strikes northwesterly for 130 m. Two diorite dykes strike northeasterly. OREBODY: Ri se And S hi ne Reef is a narrow shear and fissure-vein system hosted by a sequence of sheared, brecciated and silicified greenstone with minor phyllite, chert

*** J15

*,~*

-AGPS--1fIIIIIlIIII

....--MICROGRAPHICS BUREAU

1:1.-

-..

and shaLe. The reef is arcuate in outcrop form. Three northnorth~lesterLy trending hornbLende-biotite syenite porphyry dykes outcrop a short distance to the west. OREBODY: Shamrock MineraLisation is contained in numerous thin shear veins which are concentrated in four cLose Ly-spaced sub-para LLe L ore zones near the l4estern boundary of a smaLL stock of quartz diorite porphyry. REFERENCES: Bischoff K. , 1986 Minera Lisation in the Ki Lkivan area. IN Wi LLmott W.F. (ed) - South Burnett district. 1986 fieLd cQnference. GeoLogicaL Society of AustraLia. QueensLand Division 1v P21-30 Brooks J.H. , syvret J.N. (Sal4ers J.D. ,1974 MineraL resources of the KiLKivan district. GeoLogicaL survey of QueensLand. Report 60 GoLding S.D. , WiLson A.F. , Scott M. , Anderson p.K. , Waring C.L. , FLitcroft M. , Rypkema H.A. , 1987 Isotopic evidence for the diverse origins of goLd in QueensLand. IN Herbert H.K.(ed) - GoLd in QueensLand. proceedings of one-day symposium, universitY of Queens Land, June 1984. University of Queens Land. Department of GeoLogy. Papers 12 (1) P65-83 Is haq S. , 1986 ALLuvial goLd minin~, West Coast Mines, K'iLkivan. IN WilLmott W.F.(ed)South Burnett distrlct. 1986 fieLd conference. GeoLogicaL society of AustraLia. QueensLand Division 1v P13-15 Is haq S. , 1986 ALLuvial goLd mining, west Coast mines, KiLkivan. IN The south Burnett district. GeoLogicaL society of AustraLia. Queensland Division. FieLd conference, 1986. GeoLogicaL Society of AustraLia. QueensLand Division 1v P13-15 Jones O.A. , 1948 Ore genesis in Queens Land. RoyaL Society of QueensLand. 59 P1-91

proceedings

Warren R.G. , 1972 A commentary on the metaLLogenic map of AustraLia and Papua New Guinea. Bureau MineraL Resources, AustraLia. BuLLetin 145 00000000000000000000000000000 00 000000000

.......-

***

K15

***

- - - - - [ ~. . AGPS----..

..---MICROGRAPHICS BUREAU - - - - - - - - - - - - - - - - - - - - . . . DEPOS IT:

35

GYMP lE

DEPOSIT IDENTIFICATION: PRINCIPAL COMMODITIES: Au , MINES: Eldorado , Great Eastern, Gympie , Mary River, Monkland , New Zealand ( No. 2 South Great Eastern, North Glanmire , North phoenix , Nortn Smithfield , Orient, Orienta l , scottish Gympie , OREBODIES: Caledonian, Columbia, Glanmire , Glasgow, Great Eastern Ing lewood , Lady Mary , Monkland , New Zealand , orient Phoenix, scottish. smithfield , Victory.

,

Gympie orienta l

GROUP: Gympie Group COM~lENTS : Includes regional setting of New England Fold Belt, Gympie group, and Gympie Bloc k.

LOCATION: LATITUDE: 26 10 250K SHEET: SG56 10

LONGITUDE: 152 40 1001< SHEET: 9445

ADMINISTRATIVE SUBDIVISJON: MINING DISTICT: Gympie MINING FIELD: LOCALITY: DEV ELOPMENT HIS TORY: DISCOV ERY METHOD prospecti ng

DISCOVERY YEAR 1867 OPERATING STATUS AT 1987 MINE North Glanmi re Great Eastern No. 2 South Great Eastern Gympie E Ldorado Monk land ~lonk land Monk land New Zea land Orient

STATUS Hi stori ca l possible Hi sto ri ca l

MINING METHOD unde rg round Underground unde rg round

Historical possi ble Historical Hi sto ri ca l possi ble Historical Historical

unde rg round underground unde rg round unde rg round unde rg round unde rg round unde rg round

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.---MICROGRAPHICS BUREAU------~ ...· - - - - . -....- - - -..... OrientaL North Phoeni x Scottish Gympie Scottish Gympie North smithfie Ld

unde rg round unde rg round unde rg round unde rg round unde rg round

HistoricaL HistoricaL HistoricaL Poss i b Le HistoricaL

COMPANIES: OREBODY: Gympie COMMENTS

PRESENT OPERATORS: BHP MineraLs Ltd. EQUITY 55.00 45.00

PRESENT OWNERS; BHP MineraLs Ltd. Devex Ltd.

r.

COMMENTS

OREBODY: Monk Land COMMENTS

PRESENT OPERATORS: BHP Mi ne ra Ls Ltd. EQUITY 55.00 45.00

PRESENT OWNERS: BHP MineraLs Ltd. Devex Ltd.

r.

COMMENTS

OREBODY: scottish COMMENTS

PRESl:,'T OPERATORS: BHP MineraLs Ltd. EQUITY 55.00 45.00

PRESENT O~INERS: BHP Mi ne ra Ls Ltd. Devex Ltd.

r.

COMMENTS

PRODUCTION:

CUMULATIVE PRODUCTION (TO DEC.1986): ORE(t): 5,017,199

GOLD(kg) 106,200

RECOVERED GRADE(9/t) 21.16

COMMENTS

MAIN PRODUCTION PERIODS: 1867-1925 , RESOURCES: DATE Dec 1987

ORE('OOOt) 3,000

PRE-MINE RESOURCE SIZE:

GRADE (g /t)

GOLD( kg)

CLASSIFICATION

10.0

30,000

sub-Economic Inferred In-Situ

u/g

M

GEOLOGY:

.....

~

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M15

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.---MICROGRAPHICS

BUREAU-------------------....

PROV INCE: BLOCK: Tasman FoLd Be lt PROVINCE: New Eng L~nd orogen SUB-PROVINCE: Gymple Block HOST ROCI
their

Andesite dykes. Spatially reLated to some mineralisation. AGE: Palaeozoic Early permian STRUCTURAL FEATURES MAJOR: Faulting, Fracturing, STRUCTURAL/STRATIGRAPHIC INTERSECTIONS MAJOR: FauLt/Stratigraphic unit, IGNEOUS PROXIMITY SIGNIFICANT: Sub-Volcanism(1ntermediate) , METAMORPHISM: Kin Kin Beds to the east are metamorphosed to lower greenschist facies. ? Gympie Group metamorphosed to low grade. ALTERA nON: DEPOSIT CHARACTERISTICS: TYPES: Metamorphic auriferous Quartz veins i:1 fLysch-type metasediments (slate be It-t}·pe). Alluvia L. STYLE: stratabound , MORPHOLOGY: Lenticular, :.r-I: OF MINERALISATION: Mesozoic MiddLe Triassic DIMENS IONS: OREBODY: Gympie TRUE WIDTH

~_a-

AVE

( cm )

-..

MAX 200.0

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~~_AGPS--IIIII

....-- MIC ROG RAP HIC S

BUREAU-----------.sII---------.

NATURE OF MINERALISATION: Free Mi Lling , PRIMARY ORE: Vein (Reef) , SECONDARY ORE: DetritaL (ALLuvi aL) , MINERALOGY: OREBODY: Gympie SuLphid e zone: free goLd, trace pyrite, gaLena, sphaLe rite, chaLcop yrite, hessite . Gangue (vei ns): quartz- caLcite . Fissure fi LLing: breccia shaLe, chlorit e, calcite . pyrite is widely distributed ted through the country rocks, includin g the barren section s. GENETIC CONTROLS: Deposit is strongL y structu rally and ically contolle d. MineraL isation occurs in structur aL litholog almost exclusi vely at interse ctions with beds of favoura bleplanes litholog carbona ceous sha le (graphi te). Faults inc Luding those occupie d yby the reefs, are tension al and probabL y post-da te folding , indicati ng that mineral isation was probabL y post-fo lding, i.e. Middle Triassi c. oxygen isotope data (Golding & others, 1987) indicat e a metamor phic ore-flu id source.

=

GENETIC MODELS: There is nO obvious intrusiv e source for the minera lisation , which was possibL y orginal ly of sedimen tary or volcani origin, subsequ ently remobi lised and concent rated in quartz reefs c during foLding and dyke intrusio n in the Middle Triassi c. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Gympie REGIONAL SETTI~~: NEW FOLD BELT The New Eng Land orogen ENGLAND commenced at the end of the Si lurian and I~as stabilis ed Late in thp. Triassi c. Evolutio n proceed ed through a series of orogeni c cycLes which are interpre ted ;n terms of pLate margin tectOI)l cs. LATE SILURIAN-MIDDLE DEVONIAN A volcani c arc, the Calliop e IsLand Arc, deveLop ed at the end of the Si lurian and was active ti lL the Middle n. The arc was probabl y separat ed from the AustraL ian contine nt, Devonia represe nted by the Anakie InLier, by a margina l sea. The arc rOCKS are calc-aL kaline voLcani cs, voLcani cLastic sedimen ts, Limeston e and chert now preserv of remnant fauLt blocks - the Stanage , Craigi lee, callioped in a series e, phi Lpott and silverwo od Blocks. The arc was destroy ed and the margina l sea closed by orogene sis in the Middle Devonia n. ASSOCIATED MINERALISATION VoLcano genic massive goLd-co pper suLphid es (Mount Morgan) . LATE DEVONIAN-EARLY CARBONIFEROUS An active coverge nt Andeantype contine ntal margin volcani c arc, the connors -Auburn VoLcani c Arc, deveLop in assocla tion with a westdiJlping subduct ion zone. East of theed arc an unstabL e marine sheLf (forearc basin), the Yarrol SheLf, deveLop ed the site of the deforme d caLLiop e Arc. The sheLf was flanked over the east by a contine ntaL sLope and oceanic basin, the Wandi to Lla SLope and Basin. The arc rocks are contine ntaL caLc-aL kaline volcani cs now preserv ed in the Connors and Auburn Arches. The shelf sedimen ts are volcani clastic sedimen ts, primary voLcani cs, Limeston e and sandsto ne preserv ed in the

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.-.--MICROGRAPHICS B U R E A U - - - - - - - - -...--~-------. yarroL and campwyn B Locks. The Wandi LLa sequence comprised thick, uni form, dominantly fLysch-type sediments now preserved in the coastaL, yarraman and South d' Aguilar BLocks. The ab~ssaL pLain/VoLcanicLasitc sequences of the North d' Agui Lar and Gympie tlLocks may be part of a younger Wandi LLa depositiona L envi ronment. ASSOCIATED MINERALISATION Minor goLd deposits of sedimentary or voLcanic origin (Grasstree, Mount Tay Lor). LATE CARBONIFEROUS-EARLY PERMIAN The Andean-type morgin W
....

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.....--MICROGRAPHICS B U R E A U - - - - - -...~-----------. north-south Gympie Basin. The principal mineral deposit of the block was the Gympie 90ldfield, which was hosted by quartz-calcite r~efs at their intersectlons with carbonaceous horizons within volcaniclastic sediments of the Early permian marine succession (Gympie Group). The oldest rocks of the block are assumed to be deep marine metasediments and metavolcanics along the western margin Amamoor Beds, Goodnight Beds, and Cedarton Volcanics) which were complexly deformed in the Late Carboniferous. The Gympie Basin subsequently develol1ed as a continental margin basin from the Early Permian. The early-Middle Permian succession (Gympie Group) comprises a basal basaltic volcanic unit overlain by thick sequences of shallow marine clastics with a prominent limestone bed. Uplift in the Middle permian ~,as followed by dePosition of a thin unit of coarse fluviati le c lastics (Keefton Formation, basal Brooweena Formati on). Whi le the remainder of the New England Fold Belt remained emergent, renewed subsidence in the Gyml1ie Basin led to the resumption of marine sedimentation in the Early Triassic (Kin Kin Beds, upper Brooweena Formation). The permo-Triassic rocks were deformed and metamorphosed in the early Triassic and extensively intruded by Middle Triassic postorogenic granitoid batholiths. Middle Triassic continental silicic volcanics were eruPted over the southern part of the block. GEOLOGICAL SETTING: GYMPIE Gympie lies in the southern part of the Gympie Block, hosted by the Rammutt Formation, the lOWer of the two clastic sedimentary units of the Gympie Group. The Rammutt Formation consists of 600 m of massive to thi n-bedded sha le, i ncludi ng carbonaceous sha le, wi th i nte rbedded mudstone, si ltstone, feldspathic labile arenite~ andesite and volcanic con9lomerate. Lithologies and interbedding indlcate del1osition under raPldly changing cC'nditions with conteml1oraneous volcanism. Although Gympie lies within the permo-Triassic plutonic province, Triassic plutons are not abundant in the deposit region. The nearest intrusives are the Middle Triassic Cedar pocket porphyry and Woondum Granite which intrude Kin Kin Beds 5 km southeast of Gympie. The Gympie Group has been folded alon9 northl~est-trending axes to produce open folds with local steep dlPS and overturning. At Gympie the host sequence strikes north-northwest and dips uniformly east at 20 deg. Faults trend north-northwest and are normal or high angle reverse faults. Gympie lies on a major north-northwest fault which southeast of the 90ldfield forms the disconformable contact between the permian Gymple Group and Triassic Keefton Formation-Kin Kin Beds. The sequence at Gympie is apparentl,y repeated by faulting. Apart from the mineralised strike faults, the sequence is cut by 3 Younger sets of faults, in chrohological order:a set of bedding plane faults, a second set of strike faults, and a set of sub-parallel, east-striking dip faults, which may have throws of a few hundred metres. The country rocks are closely Jointed. Primary gold mineralisation occurred in numerouS parallel reef-fi lled fi ssures stri ki ng conformably wi th the: country roc ks but dippi ng steeply transgressively. Many reefs occupied strike faults and some are in part assoclated with andesite dykes. The reefs generally consisted of one or two veins occupying the hanging wall and footwall of the fissure with veinlets between them. Mineralisation was localised in gentlY-Ritching ore shoots which occurred at the intersections of the reefs with beds of pyritic carbonaceous shale. The shale beds carried ~raphitic "floors" within them or. were bounded above or be low by breaks". The favourable beds ('slates") consist of alternating thickbedded shale and arenite, both carbonaceous, and occupy four horizons in the Rammutt Formation. The upp.ermost and most p.roductwe "s late" bed (the "phoeni x" or "Monk land" slates) is 60 m thick and immediate ly over lain by massive volcanic cong lomerate and arenite and impure

1I!iIIIIIIaaI

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m---MICROGRAPHICS BUREAU-....- - - - - - - - - - - - - - - -....-

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Limestone. The next two productive horizons occur at 40 m and 23 m end are shaLe beds 4-5 m thick. At 183 m below these, severaL hundred metres of greywacke with LenticuLar beds of massive shaLe formed the 4th productive horizon. REFERENCES: ApLin C.O'O.H. 1868 On the geoLogicat and mining features of the Gympie goLdfieLd. LegisLative Assembly of QueensLand. Votes proceedings 1868 Oenmead A. K. , 1937 New Gympie GoLd Mines N.L. (Leases 1662, 1672, 1674, 1747). QueensLand Government Mining JournaL 38 p42-45; 41 p157 Ounstan 8. , 1914 Gympie geoLogicaL notes. scottish Gympie gold mine. QueensLand Government Mining JournaL 15 p17-19 Ounstan 8. , 1911 Geological map of Gympie, QueensLand. 18 sheets. GeoLogicaL survey of QueensLand. pubLication 2218 Ferguson J.A. , 1948 GeoLogy of the area south-east of the Gympie goLdfield. University of Queens Land. UnpubLished 1v

M.Sc.

thesis.

GoLding s.o. , Wi lson A.F. , 1980 The app Lication of oxygen isotope studies to the occurrence of gold mineraLization in eastern AustraLia. IN AusIMM Conference, New zealand, May 1980. AUs IMM. confe rence Seri es 9 P67-80 Go Ldi ng S. o. , Wilson A. F• , 1981 An oxygen and carbon isotopic study of some gold deposits of eastern Australia. Aus IMM. P roceedi ngs 278 p13-21 GoLding s.o. , Wi lson A.F. , Scott M. , Anderson P.K. , Waring C.L. , Flitcroft ~1. , Rypkema H.A. , 1987 Isotopic evidence for the diverse origins of gold in Queensland. IN Herbert H.K.(ed) - Gold in QL'eensland. proceedings of one-day symposium, university of QueensLand, June 1984. University of Queens land. oepartment of Geology. Papers 12 (1) P65-83 Jack R.L. , 1905 Scottish Gympie gold mine. QueenS land Government Mi ni ng Journa L 6 P21-24 KayJ.R.

....

,1983

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[ii]l_AGPS _ _

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..---MICROGRAPHICS

. . ----.. . .

BUREAU-----------~---

A review of metalliferous mineralisation associated with permian rocks in Queensland. IN Permian geology of Queensland. proceedings of symposium, Brisbane, July 1982. Geological society of Australia. Queensland Division 1v p343-352 Lauri e A. , 1963 The Gympie gold strike of 1867. QUeens land Gove rnment Mi ni ng Journa l 64 P404-408 Morton C.C. , 1934 Operations at the TWo Mi le, Gympie. Queensland Government Mining Journal 35 p6-7 Morton C.C. , 1934 The Dawn area, Gympie. QUeens land Government Mining Journal 35 P8 Morton C.C. , 1934 New Dawn lease applications. QUeens land Government Mining Journal 35 P9-11 cranfieLd Murphy P.R. , Schwarzbock M. Murray C.G. , 1976 Geology of the Gympie 1:250,000 sheet area. Geological Survey of Queensland. Report 96

Withnall

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Queens land Government Mi ni ng J , 1977 The gold of Gympie. Queensland Government Mining Journal 78(914) P605-608 Queensland. Department of Mine, 1953 Gympie goldfield. IN Edwards A.B.(ed) - Geology of Australian Ore deposits. 5th Empire Mining & Metallurgical Congress, Australia & I~ew Zealand, 1953, Melbourne. AusIMM 1v p813-816 QUeens land. Department of Mi ne 1987 Queensland mining historical collection - Gympie. Includes historical booklet 'Goldfields of Queensland' by W. Lees, 1899 and map by W.H. Rands,1899. Queens land. Department of Mi nes 1v Rands W.H. , 1889 Gympie goldfie ld. Geological Survey of Queensland. 52

publication

Rands W.H. , 1901 Report on the Gympie goldfield. Having special reference to the rnglewood dYke and the eastern leases. Queensland Government Mining Journal 2 p356-358

a...

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...-- -MIC ROG RAP HICS

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BU RE AU -- -- -- -- -- -- -- ~. -B -

RandsW .H. ,1901 Fourth report on the Gympie goLdfie Lds. - 11,111. Having speciaL referenc e to the IngLewo od dyke and the eastern Leases. QueensL and Governm ent Mining JournaL

2 PS2S-S29; PS94-S98

Reid J.H. , 1933 The soverei gn area, Gympie goLdfie Ld. Queens Land Governm ent Mining JournaL

34 P273-277

0000000 0000000 0000000 0000000 0000000 00000

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...---MICROGRAPHICS BUREAU-----...- - - - - - - - - - - - - -..... DEPOS IT:

AGRICOLA

36

DEPOSIT IDENTIFICATION:

---------------------SYNONYMS: Ken; Lworth ,

PRINCIPAL COMMODITIES: Ag , Au , MINES: M ri co La , Cape River , OREBODIES: Mr;coLa , GLittering HilLs, Lady May, GROUP: permo-Triassic Igneous Group COMMENTS: See Deposit No. 35 Gympie for regionaL setting of New EngLand FoLd BeLt, Deposit No. 34 Ki Lk;van for setting of Permo-Tr;assic igneous group and North d Mu; Lar BLoc k. LOCATION: ADMINISTRATIVE SUBDIVISION: MINING DISTICT: Gymp;e MINING FIELD: LOCALITY: DEVELOPMENT HISTORY:

-------------------DISCOVERY METHOD Geochemistry Dri LLing Geo Logy Geophysics

DISCOVERY YEAR 1984 1984 1984 1984 OPERATING STATUS AT 1987 MINE AgricoLa

STATUS Operating

MINING METHOD Open-Cut

COMPANIES: OREBODY: AgricoLa PRESENT OPERATORS: Astr; k Resources N L.

COMMENTS

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....---MICROGRAPHICS B U R E A U - - - - - - - - - - - - - - - - - - - - - - . . EQUITY? 100 .00

PRESENT OWNERS: Astrik Resources N L.

COMMENTS

PRODUC nON: MAIN PRODUCTION PERIODS: - , 1987- , RESOURCES: GRADE(g/t)

GOLD(kg)

CLASSIFICATION

sept 1987 82

4.5

369

Sept 1987 174

5.5

957

Sept 1987 100 sept 1987 SO

5.0 5.0

Economic Demonstrated - Indicated Economic Demonstrated - Indi c ated Economi c !l1ferred Economi c infe rred

DATE

ORE('OOOt)

500 250

Lode 1

Recoverable

o/c

Recoverable

o/c

Lode 2

o/c o/c

Lode 2 Lode 3

In-Situ In-S i tu

PRE-MINE RESOURCE SIZE: S GEOLOGY: PROV INCE: BLOCK: Tasman Fo ld Be It PROVINCE: New Eng land OroQen SUB-PROVINCE: North D'A9U1 lar Block HOST ROCKS: Booloumba Beds phyllite, slate, metamorphosed mafic volcanics. Host to go ld mi nera l isation. Tungi Creek Granodiorite Ho rnb lende-bi ot He g ranodi ori te. Intrudes mineralised metamorphics in deposit region. Neurum Tona lite Biotite-hornblende granodiorite and tonalite. Intrudes mineralisea metamorphics in deposit region. AGE: pa laeozoi c Carboni fe rous AGE: pa laeozoic Ear ly Permian STRUCTURAL FEATURES SIGNIFICANT: Faulting, STRUC TURALlS TRA TIGRAPHIC INTERS EC TIONS SIGNIFICANT: Intrusive Contact , IGNEOUS PROXHfITY

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.....--MICROGRAPHICS

BUREAU-~------------------'

SIGNIFICANT: plutonism(Granodiorite) , AGE OF INTRUSION: Mesozoic Middle Triassic AGE OF INTRUSION: palaeozoic Late permian METAMORPHISM: Greenschist, locally amphibolite, and transitional blueschist. DEPOSIT CHARACTERISTICS:

-----------------------TYPES: Auriferous quartz veins in metasediments adjacent to felsic/intermediate porp hy ry i nt rus ive. STYLE: Discordant, stratabound , AGE OF MINERALISATION: Mesozoic Middle rriassic AGE OF MINERALISATION: palaeozoic Late permian DIMENSIONS: NATURE OF MINERALISATION: PRIMARY ORE: Lode (Alteration Zone) , Vein (Reef) , MINERALOGY: GENETIC MODELS: Mineralisation 1S presumably related to late stage igneous activity associated with Middle Triassic granitoid emplacement. GEOLOGICAL SETTING OF MINERALISATION: OREBODY: Agricola Agricola occurs in the central part of the North d'Aguilar Block. The deposit is hosted by metamorphic rocks simi lar to the host rocks at Ki lkivan in the northern part of the block. The host sequence at Agricola, the Booloumba Beds, consist of phyllite, s late, and interbedded metamorphosed mafic volcanics (epidotechlorite-actinolite schist). The Boo loumba Beds are fo lded and fau lted a long north-northwest trending axes. Beddin~ and foliation are both north-northwest striking and steeply d1pping. The belt of metamorphics is intruded to the north by the Late PermianMiddle Triassic Tungi Creek Granodiorite and to the south by the MiddLe Triassic Neurum Tonalite. Severa l maj or north-northwest trendi ng norma l or hi~h-ang le reverse faults transect the metamorphics between the intrus1ve bodies. The Tungi Creek Granodiorite is a hornblende-biotite granodiorite. The Neurum Tonalite consists of 2 phases: even-grainea biotitehornblende tonalite and granodiorite, and porphyritic tonalite. The Keni lworth-Monsi ldale area has been mined in the past for copper, gold, lead and zinc in shear/fault controlled vein deposits. REFERENCES:

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~--MICROGRAPHICS

BUREAU----------------------

Murphy P.R. , schwarzbock ~1. , Cranfield Murray C.G. , 1976 Geology of the Gympie 1:250,000 sheet area. Geological Survey of Queensland. Report

Withna II

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96 0000000000000000000000000000000000000000

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