Union-Kern-A.O.G. Cabawin No. 1 spudded on 6th October, 1960, was drilled as a structural test of the petroleum potential of sediments underlying a major unconformity within the Surat Basin. The age and nature of the section below the unconformity was questionable prior to drilling the well, but it was presumed to be partly Triassic and partly Permian in age and related to the sedimentation of the Bowen Geosyncline. The drilling of the well confirmed this prognosis. In addition to providing stratigraphic information related to the petroleum potential of the Bowen Group, the well also provided information of regional significance on the Mesozoic rocks of the Great Artesian Group. Under a thin veneer of Tertiary rocks the drill penetrated the Roma, Blythesdale, Walloon and Bundamba Formations of the Great Artesian Group, and the Cabawin, Kianga, and Back Creek Formations of the Bowen Group, before bottoming in volcanic rocks of (?)Permo-Carboniferous age at a depth of 12,035 feet. The drilling of the well confirmed the presence of hydrocarbons in the Surat Basin. During the drilling operation a blowout occurred at a depth of 9938 feet, surfacing free gas and condensate. The blowout was caused by formation pressures, in excess of the mud weight, within an eight-foot sand body of the Permian Kianga Formation. In addition significant gas shows and a flow of salt water were encountered in weathered andesite of the Cracow Formation. Minor gas shows were recorded in the Permian Back Creek Formation, and in the Lower Triassic Cabawin Formation, and Significant shows of hydrocarbons were also present in porous and permeable sandstones of the lower member of the Triassic-Jurassic Bundamba Formation. The number of occurrences of oil and gas showings indicated that only a sustained testing programme through casing would properly evaluate the potential of these hydrocarbons. After reaching total depth, 5 1/2" casing was cemented at 12,033 feet, and there followed a series of production tests of all significant shOWings of oil and gas encountered during the drilling operation. Results were negative with the exception of the one zone in the Permian Kianga Formation. This zone proved to be the only producing horizon. After 22 days of continuous production, this zone was producing 62 barrels per day of 490 API gravity crude through 22/64" choke, with casing and tubing well-head pressures at 550 p.s.i. and 300 p.s.i. respectively, and 534 Mcf/D of gas. A total of 1761 barrels of crude oil and 13,744 Mcf of gas were produced during the testing period. Pressure and temperature surveys were conducted, and the well was shut in and suspended on 17th June, 1961, retained in a condition for production at any future time.

Union-Kern-A.O.G. Cabawin East No. 1 was drilled by Union Oil Development Corporation, Kern County Land Company, and Australian Oil and Gas Corporation Limited in the Surat Basin, Queensland, 4.8 miles on a bearing 0800 from Cabawin No. 1 Well. The test was undertaken to investigate the possibility that the sub-commercial oil-bearing sand in Cabawin No. 1 might have a thicker development towards the east. The well was spudded in on 18th July, 1961, and penetrated a veneer of Tertiary; the Roma, Blythesdale, Walloon and Bundamba Formations of the Great Artesian Group; and the Cabawin, Kianga, and Back Creek Formations of the Bowen Group. Minor gas shows were encountered in coaly strata in the Blythesdale and Walloon Formations. Several small methane gas shows were indicated in sandstones of the Blythesdale, Walloon, and Bundamba Formations. Some very small gas showings were obtained through the Cabawin, Kianga and Back Creek Formations. Scattered oil fluorescence was noted from 6370 feet to total depth at 12,091 feet, but there were no important shows. The well indicated that the producing Kianga sand of Cabawin No. 1 was too silty in the Cabawin East location to be a reservoir. Cabawin East No. 1 was abandoned on 17th October, 1961.

Babrongan No. 1 Well was located on the southern edge of the Jurgurra Terrace, 97 miles east-south-east of Broome, Western Australia, and approximately 11 miles south of Frome Rocks No. 2. The well was drilled by Oil Drilling and Exploration (W.A.) Pty Limited for West Australian Petroleum Pty Limited, to a total depth of 6395 feet. Drilling commenced on 29th May, 1962, and was completed on 10th July, 1962. A full programme of logging, testing, and coring was undertaken. The well penetrated 20 feet of Quaternary surface sand and clay, 230 feet of undifferentiated Mesozoic sandstone and siltstone, and 6135 feet of Palaeozoic sandstone, siltstone, shale and minor carbonate. The Palaeozoic formations or units encountered were the Poole Sandstone and Grant Formation of Permian age and the Luluigui Formation, Clanmeyer Siltstone,and an un-named unit of the Upper Devonian. At 2340 feet the well intersected a fault and/or unconformity. If a fault is present it is believed to have a throw of approximately 3000 feet. With the exception of approximately 145 feet, the Luluigui Formation has been removed. Correlation with Frome Rocks No. 2 Well shows that an additional 2572 feet of Clanmeyer type sediments are present in Babrongan No. 1. The un-named unit of the Upper Devonian has been equated to the Virgin Hills Formation. This is the first time that this formation has been suspected of being present on the Jurgurra Terrace. The presence of these sediments is considered important to further exploration in the area as the Virgin Hills Formation is associated with reef development on the north rim of the Canning Basin and may also indicate the presence of reefs on the Jurgurra Terrace. Two minor shows of hydrocarbons were noted in the well. Neither was considered to be of commercial value and no drill stem tests were run. The well was abandoned at 6395 feet because of mechanical difficulties. The stratigraphic drilling operation at Babrongan No. 1was subsidized under the Petroleum Search Subsidy Act 1959-1961, from surface to total depth.

A reconnaissance seismograph survey of the Wandagee area of the Carnarvon Basin (see Figs 1, 2) was carried out by Geophysical Service International, Party 621, for West Australian Petroleum Pty Limited between November, 1961 and February, 1962. The project area falls within Permit to Explore 28H. The survey was designed to map the structure and the stratigraphy of the Wandagee Ridge (South) area of the Carnarvon Basin. The survey commenced on 9th November, 1961, and terminated on 7th February, 1962, after covering 115 1/2 miles of reflection traverse and 33 1/.3 miles of refraction traverse. The results of these reflection and refraction surveys were combined with other geophysical data to produce an overall interpretation. There are two distinct areas of interest separated by the Wandagee Fault. The Wandagee Fault is a large down-to-the-east normal fault in the pre-Cretaceous section, with reverse movement occurring later than the Cretaceous. Devonian rocks are present at shallow depth on the west side of the fault, but there are probably 10,000 feet of Permian on the east side. East of the Wandagee Fault the north-south trending Quail Anticline was partly delineated. It is suggested that this anticline closes in Permian and perhaps in Carboniferous Devonian horizons. The geoIhysical operation undertaken in the Wandagee Ridge area, Carnarvon Basin, Western Australia, was subsidized under the Petroleum Search Subsidy Act 1959.

Union-Kern-A.O.G. Wandoan No. 1 was the first wildcat drilled by Union Oil Development Corporation in the north-eastern part of the Surat Basin. Union-Kern-A.O.G. Moonie No. 1 had proven the potential of the Jurassic-Triassic Precipice Sandstone as an oil reservoir and it was necessary to evaluate this reservoir in other parts of the basin. In the Wandoan area seismic surveys defined a large north-plunging anticline in rocks of the Bowen Group (Triassic-Permian), with a domal closure in the Great Artesian Group superimposed on the north plunge of the feature. This domal closure shows more than 200 feet of vertical closure encompassing an area of 30 square miles. Wandoan No. 1 Well, located approximately 73 miles east-north-east of Roma, was drilled by Oil Drilling and Exploration Limited for Union Oil Development Corporation to a total depth of 10,736 feet. Drilling commenced on 22nd April, 1962 and was completed on 18th June, 1962. A full programme of logging, testing and coring was undertaken. The well penetrated 4798 feet of Mesozoic sediments of the Great Artesian Group, 4468 feet of tuffaceous shale, siltstone and sandstone of the Triassic Cabawin Formation of the Bowen Group and bottomed at 10,736 feet in the Lower Triassic-Upper Permian Kianga Formation. Wandoan No. 1 was drilled primarily to test the petroleum potential of the Precipice Sandstone. The test was continued for stratigraphic information through the Cabawin Formation into the Kianga Formation. A 60-minute open hole formation test was run over the interval 3260 to 3278 feet near the top of the main porous sandstone of the Precipice Sandstone. A net rise of 2830 feet of fresh water (10 gr./gal.) was recovered in the test. A subsequent analysis indicated traces of hydrocarbons in the formation water. Another 60-minute open hole formation test over the interval 6024 to 6095 feet in the upper part of the Cabawin Formation yielded a net rise of 105 feet of slightly gassy watery mud. The stratigraphic drilling operation at Union-Kern-A.O.G. Wandoan No. 1 was subsidized under the Petroleum Search Subsidy Act 1959-1961, from surface to total depth.

A.O.G. Wentworth No. 1 Well was located in the Murray Basin, approximately 20 miles north of Wentworth, New South Wales. The well was drilled by W.L. Sides and Son Pty Limited for Australian Oil and Gas Corporation Limited to a total depth of 2081 feet. Drilling commenced on 8th September, 1961, and was completed on 14th October, 1961. A programme of coring and electric logging using a Widco unit was carried out, but no perforating, squeeze cementing, or testing operations were undertaken. The well was drilled to determine the nature of the sediments immediately beneath the Tertiary sequence, with particular reference to a refractor at a calculated depth of 1650 feet. This was thought to be basement before drilling started, but it was not identified during logging. The well penetrated 192 feet of Quaternary sands and grits; 1081 feet of Tertiary sands, silts, clays, marls, and limestones; 331 feet of Lower Cretaceous sediments, including Roma Formation Equivalents; 451 feet of Permian sandy mudstones; and bottomed in conglomerate of possible Permian age. No shows of hydrocarbons were observed during the drilling operation. In the New South Wales part of the Murray Basin, Lower Cretaceous sediments had not been previously recorded, and Permian sedimentation had been recorded in only one area, between Oaklands and Coorabin, some 250 miles east of Wentworth No. 1 Well. The off-structure drilling operation at A.O.G. Wentworth No. 1, New South Wales, was subsidized under the Petroleum Search Subsidy Act I!lS!l, from surface to total depth.

Eneabba No. 1 Well was located in the northern part of the Perth Basin, Western Australia, approximately 32 miles south-east of Dongara. The well was drilled by Oil Drilling and Exploration (W.A.) Pty Limited for West Australian Petroleum Pty Limited, to a total depth of 13,712 feet. Drilling commenced on 12th June, 1961 and was completed on 25th November, 1961. A full programme of logging and coring was undertaken. After drilling through 28 feet of Quaternary alluvium, the well penetrated 5558 feet of Lower Cretaceous to Middle Jurassic Yarragadee Formation, 276 feet of Middle Jurassic probable Cadda Formation equivalent, 3894 feet of Lower Jurassic to Upper Triassic Cockleshell Gully Formation, 960 feet of Upper Triassic Lesueur Sandstone, 436 feet of Middle to Lower Triassic Woodada Formation, and 2548 feet of Lower Triassic Kockatea Shale. The pipe stuck at 5275 feet when starting to pull out at 13,712 feet, and eventually the well was abandoned leaving 9200 feet of drill string in the hole. The well was drilled to investigate the petroleum potential and stratigraphy of the Mesozoic and Palaeozoic sediments in the northern part of the Perth Basin. The Mesozoic section was much thicker than expected at the well which had not reached the Palaeozoic when abandoned at 13,712 feet because of mechanical difficulties. Many oil shows and one strong gas show (from a fracture zone between 12,795 and 12,800 feet) were recorded in the Kockatea Shale but no formation tests were carried out because of the impervious nature of the formation. The stratigraphic drilling operation at Eneabba No. 1 was subsidized under the Petroleum Search Subsidy Act 1959, from surface to total depth.

Jurien No. 1 Well was located on the western margin of the Perth Basin, Western Australia, approximately 76 miles south-south-east of Geraldton. The well was drilled by Oil Drilling and Exploration (W.A.) Fty Limited for West Australian Petroleum Fty Limited, to a total depth of 3366 feet. Drilling commenced on 9th July, 1962, and was completed on 21st August, 1962. A full programme of logging, testing, and coring was undertaken. The well was spudded in the Coastal Limestone of Pleistocene age, and penetrated 811 feet of Lower Triassic Kockatea Shale; 2274 feet of Permian (Artinskian) sediments; 35 feet of (1) Permian sandstone, and entered Precambrian granitic gneiss at 3208 feet. The well was drilled to investigate the stratigraphy and petroleum potential of the Permian sediments in the Jurien Anticline. At least 200 feet of structural closure over eight square miles were proved for that area on the basement refractor. The main objectives were the sandstones in the Irwin River Coal Measures and High Cliff Sandstone. No potential reservoir beds were observed and only the Lower Triassic Kockatea Shale appeared to be a good source rock for hydrocarbons although minor oil traces were observed in some of the Permian section. Three drillstem tests were carried out over the intervals 552 to 595 feet, 1940 to 2020 feet, and 2196 to 2356 feet. No water, oil, or gas was recovered in any of the tests. The stratigraIilic drilling operation at Jurien No. 1 was subsidized under the Petroleum Search Subsidy Act 1959-1961, from surface to total depth.

A reconnaissance marine reflection seismic survey was conducted hi Exmouth Gulf and the open coastal waters along the west coast of Western Australia from Frazer Island to Bernier Island (see Fig. 1). The survey was a two-boat operation. The survey in the Exmouth Gulf area was controlled by a Lorac radio navigational system, and along the west coast positioning was determined by sextant angle measurements to shore beacons and landmarks. All shots were recorded on magnetic tapes which were processed into variable area record sections. The following maps were constructed: (i) On a Horizon "A" within the Upper Cretaceous Korojon Calcarenite (Exmouth Gulf area only); (ii) On a Horizon "B" near the Basal Cretaceous unconformity; (iii) On pre-Cretaceous structure; (iv) Time interval between Horizons "A" and "B" (Exmouth Gulf area only); (v) Depth of water. The Exmouth marine survey indicated that Exmouth Gulf is essentially synclinal in character in the Cretaceous and Tertiary sediments. Several major pra-Cretaceous fault trends which had already been mapped on land with the seismograph were followed beneath the Gulf. The pre-Cretaceous axis of the Cape Range Anticline was located both to the north and to the south of the surface expression of the structure. The chain of islands to the north-east of the Ca.pe Range are aligned on a structural trend. To the south of-Point Maud, the Cuvier marine survey provided a much-needed tie between the Rough Range-Cape Range area and the structurally complex area around the Salt Marsh. Some structural leads were found in this southern area and the trend of major faults was established.

Union-Kern-A.O.G. Middle Creek No. 1 was the fourth wildcat well drilled by Union Oil Development Corporation in the south-eastern part of the Surat Basin. The well, located approximately eight miles north-north-east of Union-Kern-A.O.G. Moonie No. 1, was drilled by Mines Administration Pty Limited for Union Oil Development Corporation to a total depth of 6126 feet. Drilling commenced on 19th May, 1962 and was completed on 8th June, 1962. A full programme of logging, testing, and coring was undertaken. The well penetrated 118 feet of Quaternary-Tertiary sandstone and shale; 2153 feet of Lower Cretaceous Roma Formation; 1053 feet of Lower Cretaceous-Jurassic Blythesdale Formation; 1045 feet of Jurassic Walloon Formation; 639 feet of Hutton Sandstone; 540 feet of Evergreen Shale; and 352 feet of Jurassic-Triassic Precipice Sandstone. Below the unconformity at the base of the Precipice Sandstone at 5912 feet, the test entered volcanic conglomerates and siliceous sandstones of the Permo-Carboniferous Kuttung Formation in which the well bottomed at 6126 feet. No drill stem test was carried out in tile Precipice Sandstone but high resistivity on the electric log suggests freshwater saturation. A 60-minute open hole formation test was made of a sandstone interval (5240-5263 feet) witilin the Evergreen Shale. A net rise of 4790 feet of slightly gassy water (37 gr;/gal.) was recovered on the test. In the absence of any significant shows, cement plugs were set and the well was abandoned on 10til June, 1962. The test drilling operation at Union-Kern-A.O.G. Middle Creek No. 1 was subsidized under tile Petroleum Search Subsidy Act 1959-1961, from surface to total depth.