1: 250,000 GEOLOGICAL SERIES-EXPLANATORY NOTES

BULLOO COMMONWEALTH OF AUSTRALIA

STATE OF QUEENSLAND

1: 250,000 GEOLOGICAL SERIES-EXPLANATORY NOTES Bulloo, Qld

SHEET SG/54-4 INTERNATIONAL INDEX COMPILED BY J. A. INGRAM

Published by the Bureau of Mineral Resources, Geology and Geophysics and issued under the authority of the Hon. R. W. C. Swartz, M.B.E., E.D., M.P., Minister for National Development 1971. COMMONWEALTH OF AUSTRALIA

DEPARTMENT OF NATIONAL DEVELOPMENT MINISTER: THE HON. R. w. c. SWARTZ, M.B.E., E.D., M.P. SECRETARY: L. F. Borr, D.S.C.

BUREAU OF MINERAL RESOURCES, GEOLOGY AND GEOPHYSICS DIRECTOR: N. H. FISHER GEOLOGICAL BRANCH: ASSISTANT DIRECTOR: J. N. CASEY

STATE OF QUEENSLAND

DEPARTMENT OF MINES MINISTER: THE HON. R. A. CAMM UNDER SECRETARY: E. K. HEALEY

GEOLOGICAL SURVEY OF QUEENSLAND CHmP GOVERNMENT GEOLOGIST: J. T. Wooos

Printed in Australia by the Tasmanian Government Printer, Hobart Explanatory Notes on the Bulloo Geological Sheet

Compiled by l. A. Ingram

The Bulloo Sheet area was mapped in 1967 as part of a joint project by the Bureau of Mineral Resources and Geological Survey of Queensland to investigate the .

Air-photographs at nominal scale of 1: 50,000 taken in 1948 provide an almost complete coverage of the area. Gap runs were taken in 1961 at a nominal scale of 1: 80,000. Cadastral maps at 4 miles to 1 inch scale are available from the Queensland Department of Public Lands, , and a planimetric map at 1 :250,000 scale from the Division of National Mapping, Canberra.

Access over most of the area is fairly good in dry weather, with un­ sealed graded and formed roads and a network of tracks serving the stations. However, immediately after rain these earth roads become impassable. A lack of tracks in the northwest makes access difficult in the dissected hill country of the Grey Range.

There is a regular air service from Brisbane to Township just north of the Bulloo Sheet area. Several stations maintain dry weather landing grounds for light aircraft.

Previous Investigations Before the 1967 survey no systematic geological mapping had been carried out in the area. The geology of the Great Artesian Basin was des­ cribed in general terms by Whitehouse (1954) and parts in more detail by Hill & Denmead (Eds, 1960). Aspects of the Cainozoic geology covering the area mapped were previously discussed in more detail by Whitehouse (1940, 1948).

Two seismic lines were shot in the northern part of the Sheet area in 1959 (Phillips-Sunray, 1961a) and a reconnaissance survey of the Bulloo Downs area was made in 1966 (Phillips-Sunray, 1966). Both indicated that Jurassic sediments rest directly on crystalline basement. The earlier survey also indicated a buried fault which corresponds to the Constance Monocline. A complete gravity coverage by the Bureau of Mineral Resources (Lonsdale, 1965) is given on the map. Aeromagnetic coverage of the area is afforded by two surveys (Phillips-Sunray, 1961b; Delhi-Santos, 1963) which show that magnetic basement is 1000 to 4000 feet below sea level.

3 PHYSIOGRAPHY About two thirds of the Bulloo Sheet area is covered by flat or gently undulating Quaternary alluvium and sheet and dune sand. The land rises gently from the Bulloo floodplain in the southwest (250-300 feet a.s.l.) toward higher ground ( 500-700 feet a.s.l.) in the north and east. The , the main drainage unit, flows from northeast to southwest and has a gradient of 1 to 2 feet per mile. South of latitude 28 ° 30' the river system merges with a floodout covering the southwest quadrant of the Sheet.

Mabbutt (App. 3 in Senior et al., 1968) noted that the major topo­ graphic features have resulted from denudation of a gently folded and faulted Tertiary landsurface. Woolnough (1927) believed that a Tertiary landsurface which was a peneplain over a large part of Australia developed a surface hardening or 'duricrust'. In the Bulloo Sheet area the hardened Tertiary landsurface is represented by silcrete ( silicified Tertiary quartzose sandstone) which is up to 15 feet thick, and also by a hard, brecciated, ferruginous and siliceous zone ('weathered mantle') up to 50 feet thick developed on the Cretaceous rocks. This zone contains 'soil pipes' which developed in the ancient landsurface ( Senior et al., 1968; 1969).

Although silicification is not necessarily a surface feature ( Senior et al., 1968), the silcrete hill-cappings are believed to have formed mainly at or just below a landsurface. The silcrete and 'weathered mantle' overlie a deeply weathered zone where the Tertiary and Cretaceous sediments have been kaolinized, ferruginized, and silicified to a depth of 200 feet.

In the Bulloo Sheet area, in contrast to some adjacent areas (Senior, in prep.) there are no extensive plateaux formed by elevation of the intact Tertiary landsurface. However, the silicified landsurface is preserved below much of the sandplain in the east and has been intersected in many water bores.

Where the Tertiary landsurface has been elevated, breached, and partly stripped, as in the Grey Range, the topography consists of mesas with silici­ fied caps and intervening dissected country cut in deeply weathered Creta­ ceous rocks ( Fig. 1, units 4 and 5). Slumping around the edges of the mesas is common.

In the Banner Anticline area erosion has stripped the weathered zone, exposing underlying unaltered Cretaceous sediments. The topography there is gently undulating, with less than 50 feet of relief (rolling downs; Fig. 1, unit 6).

Breakdown of the silicified sediments in the Tertiary has resulted in vast widespread gravel deposits formed either as colluvium adjacent to silcrete­ capped hills or as residuals on gently sloping surfaces (Fig. 1, unit 3).

4 ·.--.-.'::·.:·:: .·.·.·.·.

. ·.·.·. o· ~uJ A 1/uviol plains , • • O··· t::'.'.2:::;2:J1 -~~ '.:_:::: -~ ij~-;--_-__ _ :~:--_. I;~~~-~>~~·?! ;andplotfl and sand dunes · .".-~_.· . .-o. _o;: .. . . -: ·o· 0 o·· o .. ~:

. ·•. ·.: :. ~-.... _o·. S!lcrete-r.app~d mesas ·o .. . and CUtJSlclS .·,o ~ 4

~ Rolling downs ~6

.··· .._·;t. -.- :.. .:;..: : ---- .. : :..~- . •. :_;_;;_,-_~~- - -. ~--: - .. _.· H 5-4/.4-4/3

Fig. 1. Physiographic units of the Bulloo Sheet .·- A large sand sheet separates the gravel-covered rises in the eastern half. Over much of the area it is at least 30 feet thick and rests on silcrete. Most of the sand is fine and very fine grained iron-stained quartz and has probably accumulated from the breakdown of Tertiary sediments by fluvial action and aeolian reworking. Aeolian sand dunes are associated with the alluvial deposits on the Bulloo floodplain and along the margins of the floodplain and sandplain. The dunes are fixed by vegetation around the sides, but there is some movement along the crests.

STRATIGRAPHY The only rocks which crop out are sediments of the Winton (Lower to Upper Cretaceous) and Glendower (Tertiary) Formations. Most subsurface interpretation is based on extrapolation from adjacent areas where older rocks crop out or where there has been oil exploration drilling. Information was also obtained from drillers' logs and a few gamma-ray logs of water bores, and from a SOO-foot stratigraphic hole BMR Bulloo 1. The stratigraphy is summarized in Table 1.

Basement Basement granite of unknown age occurs at 2200 feet in water bore 5015 (grid ref. 160430) in the southeast, and Devonian granite crops out to the east in the Eulo Sheet area (Evemden & Richards, 1962). The area of positive bouguer gravity anomaly in the southeast probably corresponds in part to granite basement. Elsewhere basement probably consists mainly of steeply folded sediments and low grade metasediments.

Mesozoic In the east of the Sheet area the basement is overlain by a porous sand­ stone 500 to more than 800 feet thick, which is equivalent to the Hooray Sandstone (Upper Jurassic to Lower Cretaceous) that crops out to the northwest in the and Tambo Sheet areas (Exon, 1966; Exon et al., 1966). It is present in the subsurface over the whole of the southern part of the Eromanga Basin. In the type area (Tambo Sheet area; Exon, 1966) the Hooray Sandstone is a fluviatile sequence of cross-bedded sand­ stone and polymictic conglomerate. The pattern of the gamma-ray logs of the Hooray Sandstone in the Bulloo area is typical of that over much of the southern part of the Eromanga Basin (Fig. 2). A thin top sandstone overlies a mainly argillaceous sequence about 250 feet thick ( upper Hooray Sand­ stone) which in tum overlies a thick sandstone sequence (lower Hooray Sandstone). The upper Hooray Sandstone has been informally called 'tran­ sition beds' in oil company completion reports from areas farther north and west.

From electric and gamma-ray log correlation it appears that the Bungil Formation of Exon & Vine (in prep.) in the Roma-Mitchell area of the

6 TABLE 1: STRATIGRAPHY OF THE BULLOO SHEET AREA

Age Formation and Lithology Thickness Map symbol (feet) Environment Comments

Qa Sand, silt, clay, gravel Superficial Alluvial QUATERNARY Qs Fine quartz sand, minor silt Superficial Aeolian Qc Gravel, mostly silcrete Superficial Colluvial UNCONFORMITY Silcrete ( silicified quartz Chemical altera­ Glendower sandstone and conglomerate) 0-15 tion TERTIARY Formation Quartzose sandstone and con­ 0-50 Fluvia tile Tg glomerate. Minor siltstone and mudstone UNCONFORMITY A Chemically altered (kaolin­ ::i Kla & Kw ized, silicified and ferrugi­ Chemical altera­ ...0 nized) sediments 0-200 tion LOWER ro UPPER c, Winton Labile sandstone, siltstone, CRETACEOUS Formation mudstone, intraformational conglomerate, in part cal­ Fluviatile, lacus­ "' Kw i::: careous, minor coal 200-1700 trine, paludal i,?:: Mackunda Labile sandstone, siltstone, May be present o Formation mudstone, in part calcareous ? Shallow marine in western part 0 Klm Mudstone, minor labile Allam Mudstone sandstone and siltstone, in bD Kla part calcareous 200-700 Shallow marine Thin in the east i::: Toolebuc Limestone, calcareous shale ? Shallow marine May be present LOWER CRETACEOUS Limestone in western part o Wallumbilla Mudstone, siltstone, minor P:: Formation labile sandstone, in part cal­ Shallow marine Klu careous 800-1000 and continental UPPER JURASSIC TO Hooray Sandstone Sublabile and quartzose LOWER CRETACEOUS J-Kh sandstone; conglomerate, siltstone 500-?1000 Fluviatile MIDDLE TO UPPER lnjune Creek Group Siltstone; quartzose, sub­ May be present JURASSIC labile and labile sandstone; Fluviatile and in western part mudstone ? lacustrine ANGULAR UNCONFORMITY PALAEOZOIC Pz Steeply dipping indurated ? sediments, metasediments, granite GAMMA RAY LOG OF WATER BORE R 207! Depth (grid ref.142 445) in feet 0--.==---

100

200

300 WINTON FORMATION AND ALLARU 400 MUDSTONE

500

600

700

800

900

1000

1100 WAL LUM BILLA FORMATION

1200

1300

1400

1500

1600 Upper HOORAY SANDSTONE 1700

1800

Lower HOORAY SANDSTONE 1900 H 54/44/4

GM.

Fig. 2. Gamma-ray log showing typical Hooray Sandstone pattern

8 Surat Basin correlates with the upper Hooray Sandstone in the main part of the Eromanga Basin. The criterion used by Exon ( 1966) for separating upper and lower parts of the Hooray Sandstone in the type area was a local disconformity, with pebbly sandstone ('upper part') overlying finer grained sandstone ('lower part'). Evans (1966b), using wireline logs, correlated the 'upper part' with the top sandstone bed of the Hooray in Amerada Newlands 1, 300 miles north of the Bulloo area. Senior et al. (1968, plate 1) showed that the Hooray Sandstone in Newlands 1 is fairly typical of most of the southern Eromanga Basin. It is evident, therefore, that Exon's ( 1966) 'upper part' is probably only equivalent in part to the 'upper Hooray Sand­ stone' as used here.

The 'Blythesdale' seismic reflector corresponds either to the top of the upper Hooray Sandstone or the top of the lower Hooray Sandstone.

Thin Injune Creek Group equivalent sediments may occur below the Hooray Sandstone in the western part, as they are known from oil explora­ tion wells in the adjacent Tickalara Sheet area. Where it crops out farther north (Tambo and Augathella Sheet areas) the group consists of mainly argillaceous flu via tile and lacustrine sediments (Exon, 1966).

The Cretaceous nomenclature used here is that of Vine et al. (1967). Cretaceous sediments conformably overlie the Hooray Sandstone and vary in thickness from about 3500 feet in synclinal areas in the west (Phillips­ Sunray, 1961 a) to 1000 feet in places in the east.

Except in the core of the Banner Anticline, where fresh rocks are exposed, the Cretaceous rocks near the surface have been chemically altered by deep weathering and consist of kaolinized, ferruginized, and silicified sediments.

The Cretaceous sequence appears on drillers' logs and gamma-ray logs of water bores as a rather monotonous, dominantly argillaceous sequence. Subsurface subdivision of the Cretaceous Rolling Downs Group is based largely on extrapolation from areas of outcrop to the northwest. Over a large part of the Eromanga Basin the argillaceous Wallumbilla Formation and Allam Mudstone are separated by a thin limestone, the Toolebuc Limestone (Vine, 1966; Vine & Day, 1965; Vine et al., 1967). The Toolebuc Lime­ stone is generally marked by high radioactivity, prominent on gamma-ray logs ( Vine, 1966). In the Bulloo area there is no marked anomaly in the gamma-ray logs of water bores. However, these bores are all in the eastern part of the Sheet on the Dynevor Shelf ( see below), where the Cretaceous sequence is thin. In the western part, where no water bores penetrate the whole Cretaceous sequence, the Toolebuc Limestone may be present.

BMR Bulloo 1 (Fig. 3) was drilled in the southeast of the Sheet area ( grid ref. 164414) to obtain lithological and palaeontological information from the Cretaceous. Data from nearby water bores shows that the Cretace-

9 ,,., .c" C ~ 0 3 " .: ~g <("' E "'~ 0 - u u. ~i ~ 0 N 0 z Glendower Fm ~ E _Jow 0 I- 0:: u. u

100

L 200 + _Ji .Q - <( "'

[~~~:~J Conglomeratic quartz sandstone u, ::, 250 [,:·.:.'()j Fine labile sandstone 0 w u J:.~~ ·_-::j Medium labile sandstone <( I- I= t=J Mudstone, siltstone LU ~ T~inly interbedded very fine labile sandstone, Ct: u 300 ~ siltstone and mudstone l&.,~"Z:] Silicified quartz sandstone Ct: w C ,. 0 EZLL) Brecciated and silicified sediments 0 ;; _J 41 Plant fossil E @ Shelly fossil 0 350 u.

0

E 400 ,."

0 C -~ :'? .Q" <( .,E 450 @ ~ ::; 3 0 ...J I "C " © ,,~ 0" "'" u ® "' ~ 500 ~- H 54/A4/5

•. u. Fig. 3. Lithology of the Cretaceous section in BMR scout hole Bulloo No. 1 10 ous in this area is 1000 to 1500 feet thick. The Coreena Member of the Wallumbilla Formation was intercepted at 265 feet (Fig. 3). The top 155 feet of the member consists of mainly fine-grained labile* sandstone with carbonized plant fragments. From 420 to 500 feet the member consists of thinly interbedded very fine-grained labile sandstone, siltstone, and mudstone, with marine macrofossils, pelecypods, and gastropods. Foraminifera from the interval 440 to 500 feet indicate a ?middle to lower Albian age (Terp­ stra & Burger, 1969). Spores determined at 495 feet belong to Evan's (1966) K2a palynological division (Terpstra & Burger, op. cit.), which corresponds farther north to the stratigraphic interval from the lower part of the Allaru Mudstone to the upper part of the Coreena Member of the Wal­ lumbilla Formation (Burger, 1968).

The Coreena Member at this locality, therefore, grades from a shallow marine sequence into a fluviatile sandstone in the upper part, similar to that in the Tambo-Augathella area (Exon, 1966).

The sandstone from 265 to 420 feet in BMR Bulloo 1 is an aquifer traceable from drillers' logs of water bores over most of the eastern part of the Sheet area. On the Dynevor Shelf it varies from 200 to 700 feet in depth and on the eastern part of the Thargomindah Shelf it is 700 to 1000 feet deep.

The Allaru Mudstone in BMR Bulloo 1 was intersected from 75 to 265 feet. It consists mainly of mudstone and siltstone with thin beds of fine­ grained labile sandstone. It contains no macrofossils, but the interval 200 to 230 feet contains, in addition to spores, pollen, and a few arenaceous foraminifera, some dinoflagellates and acritarchs representing less than 1 percent of the microflora. This probably indicates a brackish-water environ­ ment (Terpstra & Burger, 1969). The Allaru Mudstone is thicker on the Thargomindah Shelf (about 600 feet from water-bore data), where it is probably a marine mudstone, similar to the formation elsewhere in the Eromanga Basin (Vine & Day, 1965; Vine et al., 1967).

The overlying Winton and Mackunda Formations have not been dif­ ferentiated for lack of subsurface information. The Mackunda Formation, which elsewhere in the basin consists mainly of fine and very fine-grained sandstone and contains marine fossils (Vine & Day, 1965), may occur in the west of the Bulloo Sheet but is possibly replaced eastwards on the Dynevor Shelf by terrigenous sediments of the Winton Formation. The Win­ ton Formation consists of labile cross-bedded sandstone, siltstone, mudstone, and intraformational conglomerate. Drillers' logs record thin coal seams within the formation, and siliceous plant and wood fragments are fairly common in the altered sediments. The Mackunda Formation is upper Albian

*Terminology of Crook, 1960.

11 in age, but lower Cretaceous plants have been collected from the basal part of the Winton Formation. The Winton Formation probably ranges from the upper part of the Lower Cretaceous into the Upper Cretaceous (Vine & Day, 1965).

Tertiary The Tertiary sediments rest unconformably on the Winton Formation and consist of fluviatile cross-bedded quartzose sandstone and conglomerate with minor argillaceous interbeds. The sandstone contains silicified wood and agate. Channel deposits commonly cut into the Winton Formation. There was a marked change of source area from that which supplied the labile terrestrial sediments of the Winton Formation. On the basis of lithological similarity and stratigraphical position above the Winton Forma­ tion, the Tertiary sediments are regarded as part of the Glendower Forma­ tion, which was named in the northern Eromanga Basin (Whitehouse, 1940, 1954; Vine et al., 1965). The Glendower Formation consists of the deposits of an extensive river system that extended into the southern Eromanga Basin ( Gregory et al., 1968). No fossils have been found in the formation to sup­ port a definite age but it is tentatively thought to be early Tertiary. Subsequent alteration of the sediments by weathering during the Tertiary resulted in near-surface silicification and also selective silicification of the sandstones to produce silcrete. As much as 200 feet of the underlying Cretaceous sediments were kaolinized, silicified, and ferruginized.

STRUCTURE The physiography of the Sheet area reflects the structure: the elevated areas correspond to anticlines and most alluvial areas overlie synclines. The movements which produced the folds were vertical rather than compressional. The broad symmetrical Banner Anticline has flank dips of 1 to 2 ° and probably results from draping and differential compaction of the sediments over a basement ridge. The Constance and Yakara Monoclines were probably formed by movements resulting from block faulting in the basement. These movements were accommodated in the soft overlying Cretaceous sediments by monoclinal flexure. The Constance Monocline is represented at the surface by lines of silcrete-capped cuestas dipping 10 to 15° east and 1 ° west separated by a breached core of chemically-altered Cretaceous rocks. Seismic work (Phillips-Sunray, 1961 a) indicates that below the monocline is a fault down­ thrown to the east affecting the basement and 'Blythesdale' reflectors. A similar line of cuestas dipping at about 15° is present along the Yakara Monocline, and it is inferred that the Yakara Monocline is also fault-controlled. The northeast-trending Bindegolly Fault in the northeast is possibly the continuation of this structure.

12 The line of the Yakara Monocline and Bindegolly Fault separates a typical Eromanga Basin Cretaceous sedimentary sequence (3000 to 4500 feet) resting on the Thargomindah Shelf to the west from a thinner sequence (less than 2000 feet) on the Dynevor Shelf to the east (Vine & Day, 1965; Vine et al., 1967; Senior et al., 1969). The Mackunda Formation and Toolebuc Limestone are not present on the Dynevor Shelf and the Allaru Mudstone is considerably thinner than on the Thargomindah Shelf.

The Dynevor Shelf corresponds to the western part of Whitehouse's (1954) Eulo Shelf, which has been subdivided by Senior et al. (1969) into three basement elements, the Dynevor Shelf, the Eulo Ridge, and the Cunna­ mulla Shelf. The Dynevor Shelf passes eastwards into the Eulo Ridge (Eulo Sheet area) where granite basement crops out.,

The edge of the Dynevor Shelf apparently swings south from the Yakara Monocline, and in Urisino Sheet area (New South Wales) the shelf edge shows as a relatively steep gradient on the basement surface plotted from water-bore data (Brunker, 1966).

A marked east-west lineament at grid ref. 63/45 is shown by seismic work (Phillips-Sunray, 1966) to correspond to a subsurface fault down­ thrown to the north. In the Bulloo floodplain east of the Constance Mono­ dine seismic evidence (Phillips-Sunray, 1961 a) indicates a syncline with about 4500 feet of sediment resting on basement. A structural depression occurs beneath the Bulloo floodplain in the southern part of the Sheet area. It corresponds to a gravity 'low' and water-bore data on the Urisino Sheet area (Brunker, 1966) indicates that the Rolling Downs Group is at least 3000 feet thick.

GEOLOGICAL HISTORY The basement rocks were folded, slightly metamorphosed, and intruded by granite in the late Silurian to early Devonian times. Until the end of Triassic time the Bulloo area was probably a land area contributing sedi­ ment to the Adavale Basin in the north and the Cooper Basin in the west.

The western side of the Thargomindah Shelf was possibly covered by fluviatile sediments during the Lower or Middle Jurassic. During the Upper Jurassic fluviatile sedimentation was widespread and the Hooray Sandstone completely covered the area. A marine transgression occurred in the Lower Cretaceous and marine argillaceous sediments were deposited during Aptian and lower Albian times. Towards the end of deposition of the W allumbilla Formation the sea regressed from the eastern part of the Sheet area and fluviatile sediments were deposited. The sea transgressed again during deposi­ tion of the Allaru Mudstone, except possibly in the east of the area, where part of the Allaru Mudstone may have accumulated in brackish water.

13 After deposition of the Allaru Mudstone the sea once more receded and arenaceous sedimentation started. In the east the arenaceous sediments are probably terrestrial (Winton Formation), whereas in the west they were possibly first laid down under marine conditions (Mackunda Forma­ tion) which gradually changed to terrestrial conditions (Winton Formation) as the sea regressed.

Terrestrial sedimentation continued during part of the Upper Cretaceous. Uplift and erosion occurred at the end of the Cretaceous, accompanied by deep weathering. Fluviatile deposits were laid down probably in a system of south-flowing rivers. Deep weathering during the Tertiary resulted in kaolinization, ferruginization, and silicification of the Tertiary and Cretaceous sediments, which were further folded and faulted later.

ECONOMIC GEOLOGY Groundwater An artesian supply of fresh water is obtained from the Jurassic Hooray Sandstone. However, this has been tapped only by bores on the Dynevor Shelf, where the depth to the aquifer is generally less than 1500 feet; on the Thargomindah Shelf it is between 2000 and 3500 feet and no bores have penetrated so far. There are four flowing bores on the Dynevor Shelf (1615, grid ref. 182456; 7356, grid ref. 171456; 12900, grid ref. 177488; 15286, grid ref. 179443) and the supplies range between 2800 and 4000 gallons per hour. One flowing bore is abandoned (9686, grid ref. 176428) and two bores (2072, grid ref. 142446; 5124, grid ref. 666429) which also tap the Jurassic aquifer have ceased to flow and are pumped.

The subartesian bores mainly tap aquifers in the Cretaceous Rolling Downs Group. Sandstone in the Coreena Member is an important sub­ artesian aquifer; others occur in the Winton Formation. Water bore 13488 (grid ref. 644454) has a very small flow from an aquifer in the Winton Formation. Some shallow bores may be tapping water from Tertiary sedi­ ments. The wells, which range in depth from 30 to 84 feet, tap water from Quaternary and Tertiary sediments.

The pumped supply from the subartesian bores ranges from 270 to 2800 gallons per hour. The quality of water in the subartesian bores and wells varies greatly from fresh to brackish, but is generally suitable for stock.

Oil and Gas No potential oil-bearing sediments older than Jurassic are likely to occur in the subsurface in the Bulloo Sheet area. Potential reservoir sand­ stones which possess good porosity and permeability occur in the Jurassic. However, elsewhere in the Eromanga Basin only minor shows of oil and gas

14 have been obtained from Jurassic and Cretaceous sediments, and the sand­ stones are saturated with fresh water. If Lower and Middle Jurassic sedi­ ments occur below the Hooray Sandstone in the west of the Sheet area, potential stratigraphic traps might exist where they pinch out eastwards.

Construction Materials Abundant sand and gravel are available for supplying local needs. Silcrete gravel is commonly used in roadmaking and to construct causeways across watercourses.

15 BIBLIOGRAPHY

(Unpublished reports marked * refer to operations subsidized under the Petroleum Search Subsidy Acts, 1959-1964; copies are available for study at the Bureau of Mineral Resources, Canberra and the Geological Survey of Queensland.) BRUNKER, R. L., 1966-1 :250,000 Geological Series Urisino. Geol. Surv. NSW explan. Notes SH/54-8. BuRGER, D., 1968-Palynology of marine Lower Cretaceous strata in the northern and eastern Eromanga Basin, Queensland. Bur. Miner. Resour. Aust. Ree. 1968/62 (unpubl.). CASEY, J. N., 1959-New names in Queensland stratigraphy: southwest Queensland. Aust. Oil Gas/., (12), 31-6. CoNNAH, T. H., and HUBBLE, G. D., 1960-Laterites, in The geology of Queensland. I. geol. Soc. Aust., 7, 373-86. CRESPIN, I., 1955-Some Lower Cretaceous Foraminifera from bores in the Great Artesian Basin. /. Roy. Soc. NSW, 89, 78. CRESPIN, I., 1963-Lower Cretaceous arenaceous Foraminifera of Australia. Bur. Miner. Resour. Aust. Bull. 66. CROOK, K. A. W., 1960-Classification of arenites. Amer. I. Sci., 258, 419-28. *DELHI-SANTOS, 1963-Final report on Coopers Creek aeromagnetic survey. Delhi Australian Petroleum Ltd and Santos Ltd (unpubl.). DUNSTAN, R., 1916-Queensland geological formations. Appendix B to HARRAP, G.-A SCHOOL GEOGRAPHY OF QUEENSLAND. Dept Public Instruction, Brisbane. EVANS, P. R., 1966a-Mesozoic stratigraphic palynology in Australia. Aust. Oil Gas /., 12(6), 58-63. EVANS, P. R., 1966b--The palynology of Amerada Newlands No. 1 Well, Queensland. Bur. Miner. Resour. Aust. Ree. 1966/186 (unpubl.). EVERDEN, J. I., and RICHARDS, J. R., 1962-Potassium-argon ages in eastern Australia. I. geol. Soc. Aust., 9(1), 1-49. ExoN, N. F., 1966-Revised Jurassic to Lower Cretaceous stratigraphy in the southeast Eromanga Basin, Queensland. Qld Govt Min. /., 67, 233-40. ExoN, N. F., in prep.-Roma, Qld-1 :250,000 Geological Series. Bur. Miner. Resour. Aust. exp/an. Notes SG/55-12. ExoN, N. F., GALLOWAY, M. C., CASEY, D. J., and KIRKEGAARD, A. G., 1966-The geology of the Tambo, Augathella, and Blackall 1 :250,000 Sheet areas, Queens­ land. Bur. Miner. Resour. Aust. Ree. 1966/89 (unpubl.). ExoN, N. F., and VINE, R. R., in prep.-Revised nomenclature of the 'Blythesdale' sequence. Qld Govt Min. J. GEOLOGICAL SURVEY OF QUEENSLAND, 1960-65-0ccurrence of petroleum and natural gas in Queensland, and supplements 1-5. Geol. Surv. Qld Pub[. 299. GREGORY, C. M., SENIOR, B. R., and GALLOWAY, M. C., 1967-The geology of the Connemara, Jundah, Canterbury, Windorah, and Adavale 1 :250,000 Sheet areas, Queensland. Bur. Miner. Resour. Aust. Ree. 1967/16 (unpubl.). HARDING, R. R., 1969-Catalogue of age determinations on Australian rocks, 1962- 1965. Bur. Miner. Resour. Aust. Rep. 117. HILL, D., and DENMEAD, A. K., Eds, 1960-The geology of Queensland. /. geol. Soc. Aust., 7. JEWELL, F., 1960-Great Artesian Basin aeromagnetic reconnaissance survey 1958. Bur. Miner. Resour. Aust. Ree. 1960/14 (unpubl.). KAPEL, A., 1966-The Cooper Creek Basin, Aust. Oil Gas J., 12(9), 24-30. KING, D., 1960-The sand ridge deserts of Australia and related aeolian landforms of the Quaternary arid cycles. Trans. Roy. Soc. S. Aust., 83, 99-108. LONSDALE, G. F., 1965-Southern Queensland contract reconnaissance gravity survey using helicopters, 1964. Bur. Miner. Resour. Aust. Ree. 1965/251 (unpubl.). PHILLIPS-SUNRAY, 196la-Quilpie-Thargomindah-Charleville seismic survey, Qld, 1959- 1960. Bur. Miner. Resour. Aust. Petrol. Search Subs. Acts Pub[. 19.

16 *PHILLIPS-SUNRAY, 1961b-Geophysical report on an aeromagnetic survey of the Quilpie-Charleville-Thargomindah area, Queensland. Phillips Petroleum Co. and Sunray Mid-Continent Oil Company Ltd (unpubl.). *PHILLIPS-SUNRAY, 1966-Reflection seismic survey Bulloo Downs area. ATP 109P, Qld. Phillips Aust. Oil Co. and Sunray D.X. Oil Co. (unpubl.). PRESCOTT, J. A., and PENDLETON, R. L., 1952-Laterite and lateritic soils. Comm. Bur. Soil Sci. tech. Comm. 47, 1-51. SENIOR, DANIELE, 1971-Thargomindah, Qld-1 :250,000 Geological Series. Bur. Miner. Resour. Aust. exp/an. Notes. SG/54-16. SENIOR, B. R., GALLOWAY, M. C. INGRAM, J. A., and SENIOR, DANIELE, 1968-The geology of the Barrolka, Eromanga, Durham Downs, Thargomindah, Tickalara, and Bulloo 1 :250,000 Sheet Areas, Queensland. Bur. Miner. Resour. Aust. Ree. 1968/35 (unpubl.). SENIOR, B. R., INGRAM, J. A., THOMAS, B. M., and SENIOR, DANIELE, 1969-The geology of the Quilpie, Charleville, Toompine, Wyandra, Eulo, and 1 :250,000 Sheet areas, Queensland. Bur. Miner. Resour. Aust. Ree. 1969/ 13 (unpubl.). SPRIGG, R. C., 1958a-A new look at the Great Artesian Basin. Aust. Oil Gas J., 5(2), 13-7. SPRIGG, R. C., 1958b-Petroleum prospects of western part of Great Artesian Basin. Bull. Amer. Ass. Petrol. Geol., 42, 2465-91. SPRIGG, R. C., 1961-0n the structural evolution of the Great Artesian Basin. APEA J., 1961, 37-56. SPRIGG, R. C., 1965-Progress of exploration for petroleum in the central and western Great Artesian Basin. 8th Comm. Min. metall. Cong., 5, 167-78. TERPSTRA, G. R. J., and BURGER, D., 1969-Micropalaeontology and palynology of samples from BMR Bulloo No. 1 Scout hole. Bur. Miner. Resour. Aust. Ree. 1969/39 (unpubl.). VINE, R. R., 1964-New Tertiary stratigraphic units, western Queensland. Qld. Govt. Min. J., 65, 470-74. VINE, R. R., 1966-Recent geological mapping in the northern Eromanga Basin. APEA J., 1966, 110-15. VINE, R. R., and DAY, R. W., 1965-Nomenclature of the Rolling Downs Group, northern Eromanga Basin, Queensland. Qld Govt Min. J., 66, 416-21. VINE, R. R., DAY, R. W., CASEY, D. J., MILLIGAN, E. N., GALLOWAY, M. C., and ExoN, N. F., 1967-Revised nomenclature of the Rolling Downs Group, Ero­ manga and Surat Basins. Qld Govt Min. J., 68, 144-51. VINE, R. R., JAuNCEY, W., CASEY, D. J., and GALLOWAY, M. C., 1965-Geology of the Longreach-Jericho-Lake Buchanan area. Bur. Miner. Resour. Aust. Ree. 1965/245 (unpubl.). WHITEHOUSE, F. W., 1940-Studies of the late geological history of Queensland. Univ. Qld Dep. Geo/. Pap., 2, 2-40. WHITEHOUSE, F. W., 1941-The surface of western Queensland. Proc. Roy. Soc. Qld, 53, 1-22. WHITEHOUSE, F. W., 1948-The geology of the Channel Country of southwestern Queensland. Qld Bur. Invest. Bull. I, 1-28. WHITEHOUSE, F. W., 1954-The geology of the Queensland portion of the Great Aus­ tralian Artesian Basin. App. G. to Artesian water supplies in Queensland. Dept Co-ord. Gen. Pub/. Works, Qld. WooLNOUGH, W. G., 1927-Presidential Address, Part 1-The chemical criteria of peneplanation; Part II-The duricrust of Australia. J. Roy. Soc. NSW, 61, 17-53. WoPFNER, H., 1960-0n some structural development in the central part of the Great Australian Artesian Basin. Trans. Roy. Soc. S. Aust., 83, 179-93. WoPFNER, H., 1963-Post-Winton sediments of probable Upper Cretaceous age in the central Great Artesian Basin. Ibid., 86, 247-53.

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