098G37 BMit^(707'Il'ACTUS --- (LENDING SZCLION)
RESOURCES, GEO PHYSICS
3 UR EAU OF M[IINI E0_.OGY -
-
RECORD Record 1982/16
SHALLOW STRATIGRAPHIC DRILLING, NORTHWEST EROMANGA BASIN, OCTOBER 1981
by
D .L . GIBSON The information contained in this report has been obtained by the Bureau of Mineral Resources, Geology and Geophysics as part of the policy of the Australian Government to assist in the exploration and development of mineral resources. It may not be published in any form or used in a company prospectus or statement without the permission in writing of the Director.
Record 1982/16
SHALLOW STRATIGRAPHIC DRILLING, NORTHWEST EROMANGA BASIN, OCTOBER 1981
by
D.L. GIBSON
iii
CONTENTS
Page ABSTRACT INTRODUCTION^
1
DRILLING OPERATIONS ^
1
WIRE-LINE LOGGING^
2
DESCRIPTION OF HOLES ^
2
1MR Boulia 10-10A-10B^
2
BMR Springvale 9^
4
BMR Bedourie 1^
6
APPENDIX I - Core Recovery Details
FIGURES
FIGURE 1. Locality map FIGURE 2. BMR Boulia 10B FIGURE 3. BMR Springvale 9 FIGURE 4. BMR Bedourie 1
ABSTRACT
The Cretaceous Toolebuc Formation was cored in three shallow stratigraphic drill holes in the northwest Eromanga Basin in October, 1981, as part of the NERDDC Oil Shale Methodology Project. In these holes, the formation consists mainly of interbedded fossiliferous, thin-bedded to laminated, dark mudstone, sandy coquinitic limestone, and rare calcareous sandstone; a 50-75 cm bed of sandy coquinite with thin mudstone interbeds is present at the top of the formation, and one or two 10-50 cm beds of sandy coquinite are also present. ^A gamma-ray anomaly is associated with part of the Toolebuc Formation, but extends downwards into the topmost part of the Wallumbilla Formation in at least one hole. The Toolebuc Formation is conformably overlain by the Allaru Mudstone, but in all three holes, the relationship with the underlying Wallumbilla Formation is masked by the junction between two cores.
G len or
- m i• to n.
1304,1;0,
1.3.°30'
23 . 00 .
Mexch.tfie
(
14 . oe"
0
e o d00, /
Bexl ow le
2.4°30"
1 3,4 15'
i0^ te , oje^To• le_ lorrc ,
ti oft
Er"fnanoa CO-1,102oc
Baal-Men,.
O.
I
114.0 .
SO km
I 250 Opo SInect
80,10 OLOWC
koftte.S!'e..d.
Cover ft, Eren,
-.17 ...
ISM 4. 5tra:t (this rec.rd)
FIG. 1. LOCALITY MAP
cl- tj klt
5c;
INTRODUCTION
The NERDDC Oil Shale Methodology Project is being carried out jointly by the Bureau of Mineral Resources and CSIRO's Fossil Fuel Division.^This record summarises the stratigraphy and lithology of three holes drilled through the Cretaceous Toolebuc Formation in the northwest Eromanga Basin in late 1981 as part of this project (Figure 1). The original drilling plan called for five or six holes to be drilled in the Boulia, Springvale, and Bedourie 1:250 000 Sheet areas, but rig breakdowns and climatic conditions reduced this to three in the time available.^The hole BMR Boulia 10B is about 10km NNE from BMR Boalia 3A, which contains the type section of the Toolebuc Formation (Senior and others, 1975).
DRILLING OPERATIONS
Drilling was carried out between the 15 and 31st of October 1981, using a Mayhew 1500 rig operated by Afrac Drilling Pty Ltd of Brisbane.^Holes were drilled with air until they became too moist for clean recovery, and then by foam, or occasionally, water injection. Potassium chloride was added to the injected foam'or water in an attempt to stabilise the hole. ^A 4.6 m split tube core barrel took HQ size cores. Hole instability and high mud pressures resulted in slow coring, and in some cases, poor recovery.^These problems might have been alleviated by use of mud-drilling, but lack of equipment and mud additives prevented use of this method.
2.
Cuttings were collected at 2 m-intervals whilst drilling, but not while coring. ^Cuttings were washed before packing, and cores were wrapped in heavy duty polythene film, and packed in standard BMR core bags and boxes for transport to Canberra.^Cores and cuttings have been deposited in the BMR Core and Cuttings Laboratory, Fyshwick, A.C.T., where they have been registered and slabbed, and are available for examination subject to approval by the Director, BMR. ^Core recovery details are given in Appendix I. Hole names follow standard BMR practice of using the 1:250 000 Sheet name, and the sequential number of BMR hole within that Sheet area.
WIRE-LINE LOGGING
Each hole was logged by the BMR truck-mounted logging unit. Only gamma logs were taken, owing to poor hole conditions and lack of water in the holes (resulting from drilling with foam). ^Considerable time was spent trying to get the logging tool past blockages in the holes, particularly within the Toolebuc Formation. ^However, after reaming and cleaning, a near-complete log of each hole was taken.
, DESCRIPTION OF HOLES
BMR Boulia 10, 10A and 10B Location: About 2 1i km southwest of Charters Bore, Pollygammon station, at the intersection of the track between Charters Bore and Pollygammon Bore and - a very old, disused fenceline, which is visible only as a line of occasiona'
Depth
G-0,..6.^Lc,3^(A PI^ur.its)
L;^117
C orts
Rock,^Se-scrif+ion
and^Stra4nr-.1.1.64^UK. tfi
("I)
•^
50^ioo^tso^2oo _I^1 •
—
— 1 co
0 "
—1. oo
1.00^5.; 1
_ _1 _
^.00 i.. u
.>
, -10 ^. ^r o
AL I-Aft ll _3.3^K ho.k: - re, no4.,^+b 3 r- el^6.1^ - e. MU0510b4 -^E
•-•
il
«^..
:(4. -
^ 1^s4s4 Its^a•nd^ro.a^vary re..-.
+k: n^6 0-,As^
•f^b
-
,..,6ste4 CO
I ■ rflasfone
a.„o
— a-
-.
...... .^. —
,..
...
T .
36. 0
100 La
—L_-^—1.-
,
———
—^
_I__
BUG
3(.43 - 41.37^Thin-bedded, l'..,1-e."-bre.dricd cla..-k
sr....i ,-,,,,x15-4,,,, , a^(and^s0.,d y co/ 0 ■ .., ; te.
Po RJA AT to i,.1
—l_^-../.
41--31 -42.-75^Sond7^c-ovin'el-t. i&A-1.■ 9i.tin
.
_L_
rr,..asior‘e beds 41.75 - 48.9, mi., - ^btu:Wed , Inteebedd eel dar-k 3 my rn was t 0..a. aand, sandy^cc.i vini te.
L.
--L.-^_....
..S4•011
____ .
q
31.i3 - 14.45 11;.+,.”- b...-1-e41^sod y^c..elu
WA LLUM 61 L L. A
—
42' . 96 '^4-941^Pyr;t;c^Sandy^ten,ta 4-9 • II - Sli.01^Pcark ire. y , nen - c...1c. r•eo us rna.asive^resuet.Sto•st.
5.."----FOR MAT ION
FIG. 2.^BMR BOULIA 108
4.
posts (just visible on 1970 RC9 series airphotos; Run 6, nos 0271-0275). Metric grid reference VA 7689, lat. 22 ° 42'25"S, long. 140 ° 46'05"E. History: Boulia 10 commenced 15/10/81 and abandoned at 36.69 m on 16/10/81 when cuttings thought to be from the Toolebuc Formation were recognised, as the aim of drilling was to obtain as complete as possible cores of that Formation. ^Boulia 10A drilled to 18.00 m on 16/10/81 and abandoned due to collapse of the hole.^Boulia 10B commenced 16/10/81 and finished 17/10/81 at 54.01 m. ^The hole had to be reamed and cleaned on 18/10/81 before any wire-line logs could be taken.^1.5 in of temporary casing was used to stabilize the top of the hole. Results:^The stratigraphy and lithology of the hole are summarised in Figure 2.^There were core losses immediately above and below what is recognised as Toolebuc Formation, and thus stratigraphic relationships cannot be determined. ^The well known 'Toolebuc gamma anomaly' occurs partly within the Wallumbilla Formation. ^The three coquinite beds shown in the lithologic log appear to correlate well with lows in the gamma log about 1 m deeper than the beds; thus a small amount of mis-match may be present.
BMR Springvale 9 Location: Near water bore, registered number 14318, about 6.2 km ESE of Warra Station homestead. ^Lat. 23 ° 08'10"S, long. 140 ° 37'50"E. History: Commenced drilling on 18/10/81, and put in 6.4 in of casing. Commenced coring at 109.75 m on 20/10/81; rig broke down after 2 cores taken. Coring re-commenced on 24/10/81, and hole completed at 140.12 in
^
C•et
1.5 (PP.t un;+,) .
R ock
5ten.4 iy-of ki c.^ts
A LLu vi UM
0 - 3 -00 Se....■^;It
1. Oa -
-00 «suas4oAe...
•oo - 11-00
em ock^ b co,NN .^5 f^.4,24
re.^s 1-0"
—30
— ii•00_ to7.10
— 50
60
—10
w;+1._
104.80- 110.%^ bois
ef^dy fesOS
—i10
130 .76 - i3i•^13;o1-v,i0ce.r, sawly ^ ; n■ o.I4.0.1 net- muds b... interba4s 1S4.10^
111..q0
bcdde-el.
c^Se sq^Z^ Scsesst Ste•-se ei etv , I.sred - frt..= 2^cepArC,te., - I. t2 Dark^,
-f
, 50..6 1 6,^ai0.1,,b0.ted.?
— 140.12.
FIG 3. BMR 5FRINGVALE 9
6.
and logged on 25/10/81.^Casing retrieved and hole plugged on 26/10/81. Results: The stratigraphy and lithology of the hole are summarised in Figure 3.^The top of the Toolebuc Formation is clearly marked by 50 cm of sandy coquinite with minor mudstone, overlain conformably by fossiliferous, slightly calcareous mudstone of the Allaru Mudstone. The base of the Toolebuc Formation is masked by the junction between two cores; the loss in the core immediately below the Toolebuc (core 8) is shown in Figure 3 to be at the bottom of the cored interval, but this is not certain.^There appears to be no relationship between the gamma log and lithology, unless there is a discrepancy of about 2.5 m, in which case the anomaly would lie wholly within the Toolebuc Formation.
BMR Bedourie 1 Location: At the site of the abandoned petroleum exploration well, FPC The Brothers 1; 2.4 km SSE of the Kamaran Downs/Sandringham
boundary fence on the Sedourie-Sandringham road.^Lat. 24 ° 16'05"S, long. 139 ° 20 1 35"E. History: Commenced on 27/10/81, reached 88.47 m on 28/10/81 when
rain stopped drilling.^Recommenced on 30/10/81, and finished at 134.02 m and logged on 31/10/81.^38.6 m of casing cemented in hole. Hole plugged with cement at surface.
^
(leek
0,..,,,,, 0.^L....1^OA P 1^un; i-s)
L.i4.t.3
CO3-.3
Roc.k^cA CSC,.
P
'
(,) o^So^,,,,,^,5,
-1.00 -
ASOLI AN^SAND
0 - 2 - 00^owe
4-. vc, /^f•...- ....-• 1 :•,^sg......i
a.co - 2 t.00^We-a- tin
-10
vorooci-^3
i p-1;fe-o-ow
Inudsto.,_
-10
-30
-..0
-50 18 .cc - f
5,^al., k^gra, 0...,13+41..a , .11:11017
7.
,^ve.-O:7^6.1,^idosoo. of^V .5.,; tr..
ALL ARV mu Ds -T- 6N E >-. ,
-60
--
.
)
0 J ...) L
- 70
r':' . _ -- -- -—
..^0 .^. :-
8154 - 87.72^sh,....- .4^,c,l s.mws,..4^lin,54, L.,=,411.1,,: no^so. q...o.oi o.l^c:a.st.i^o f^r"..,I.srone..11•ss;bic •-'1,,,it
•
-90
8/.72 -105.00 \ t.111^de..-k^.v-ey .. res .^..1$415,/2_, ava.n..", 4c^lp.b ..^5,--,,!:-..&^■ -•^)2,3,1 6...14,•-,-/^c....,i-e.....,.... )^2, .........^41,.....c.k. - t....,i,^liy, • re-^b......d. .100 1of ..3 - /OS 76^3:co..c...,:to:=.^snows./^croco,OrikLe-
—
Of ..imasmoms -11:. ow.110
4
I.
2..' r,
;
1°S•CI.)---^
____ _ _ ____ "rOOLF-BUC
-
FoRma-now
.... —
_
wie., irw,../o,le,^ow,431-rowc..^...ter beroO]
105.74-104.24.^..-,4e.-1,...,idaa^a......).^....,e14,,, e., S...Nok7^1“.....5....-.C. o,....o.l...";..e.- {.1.'.1.. ^5....43.• LOG•Ly
-
-116-03 - -^-^ 7 - - -
-110
.1"---
.t-^v.IALLurm
0 7^cia,k r.....,151,,,. ooall.t.^woonce
7- tt3.!4.^;rt-terbe.elciezi^So"c1./^1:-...c64-o.-
wco-->'. ..-
-
01
Srooworool 1:owo c 6 {■••••■ A-^...e.gli^, 66, 1 C^sorow.‘154.ne
BILL FA
--^-^FoRMAT torq
-117.
fotoot- a%
,
0
3 ^ri- ,,,,'K^-...1 14..., t,^S•-••11^■••
,....o■lto.^o•o.....e , ^U....se s40,,
Ilf,...3 -11 ,4•01.^r1ow
inTeebtdoS
-^Goettuot.00s^c-L.o.ric
..-w 4,,a^t:-.0.....(?) -i- ^at.iz_ ilz.
r..-.A 5
-730
FIG.
4.
BMR BEDOURIE 1
iv...,^o...:Oot- nwO no ,^.5 r...c1 , -t-0•••
8
Results: The stratigraphy and lithologies encountered in the hole are summarised in Figure 4. ^The Allaru Mudstone conformably overlies the Toolebuc Formation, but the boundary between the Toolebuc and Wallumbilla Formations was not preserved in the core. ^There appears to be quite good correlation between the gamma log and lithology, the two limestone beds in the Toolebuc Formation corresponding to marked lows in the log(allowing for discrepancy of about 0.5).^This discrepancy means that the maximum peak in the log occurs almost exactly at the presumed base of the Toolebuc Formation.
9.
REFERENCES
SENIOR, B.R., EXON, N.F., & BURGER, D., 1975 - The Cadna-owie and Toolebuc Formations in the Eromanga Basin, Queensland. Queensland Government Mining Journal, 76(890), 445-455.
^ ^ 10.
APPENDIX I. CORE RECOVERY DETAILS CORE NO.^INTERVAL CORED
^
AMOUNT RECOVERED^% RECOVERY
Boulia 10B Core 1^30.25 - 34.85 (4.60)^4.14^90 2^34.85 - 37.85 (3.00)^1.72^57 3^37.85 - 41.30 (3.45) ^3.25^94 4^41.30 - 45.90 (4.60) ^4.52^98 5^45.90 - 49.18 (3.28) ^3.28^100 6^49.18 - 50:21 (1.03) ^.90^87 7^50.21 - 54.01 (3.80)^3.70^97 23.76^21.51^91 Springvale 9 Core^1^109.75 - 114.35 (4.60)^4.55^99 2^114.35 - 118.95 (4.60)^4.25^92 3^118.95 - 120.45 (1.50)^0^ 0 4^120.45 - 125.05 (4.60)^4.32^94 5^125.05 - 127.75 (2.70)^2.43^90 ^6^127.75 - 132.47 (4.72)^4.63^98 7^132.47 - 137.02 (4.55)^4.55^100 8^137.02 - 140.12 (3.10)^1.92^62 30.37^26.65^88 ^Bedourie 1 Core 1^79.27 - 83.87 (4.60)^.80^17 2^83.87 - 88.47 (4.60)^4.50^98 3^102.76 - 107.36 (4.60)^4.40^96 4^107.36 - 111.58 (4.22) ^3.80^90
5^111.58 - 116.18 (4.60)^4.45^97 6^116.18 - 120.78 (4.60)^1.62^35 ^27.22^19.57^72
TOTAL^
^ 83 81.35 m cored^67.73 m recovered
