From 1 - 10 / 2076
  • Legacy product - no abstract available

  • The Lambert Graben is a deep crustal depression currently occupied by the Lambert Glacier and its tributaries. The mapped area extends from 76°S to 66°S and trends in a north north easterly direction, paralleling the direction of the graben.

  • Legacy product - no abstract available

  • Geological reconnaisance on the Macdonald and Rawlinson sheet areas has shown an aggregate thickness of 27,000 feet of Precambrian sedimentary rocks. These rocks have been divided into Lower and Upper Proterozoic but only on the north-east corner of the Macdonald sheet is the unconformity between the two sequences visible. Possible Archaean gneiss and quartzite have also been differentiated in the north-east Macdonald area, These rocks are similar to those in the Arunta Complex of the Alice Springs area. No relationship is visible between these rocks and those mapped as Lower Proterozoic.

  • The Machattie 4-mile Sheet area in western Queensland was mapped in 1960. Surface mapping and examination of water bore logs established a sequence of at least 2750 feet of Cretaceous rocks, which are, in places, unconformably overlain by up to 55 feet of Tertiary sediments. Possible basement rocks were struck in Cluny No. 1 and Coorabulka No. 10 bores. The Cretaceous rocks form the main aquifer and impermeable cap of the western portion of the Great Artesian Basin. The Lower Cretaceous shales of the Wilgunya Formation are possible source rocks for petroleum. Source rocks also occur in the Lower Palaeozoic succession to the north, in the Boulia 4-mile Sheet area. The sandstones of the Lower Cretaceous Longsight Sandstone are possible reservoir rocks in the Machattie area. Neither oil nor gas has been recorded from any of the bores (11 artesian, 2 sub-artesian). Showings were reported from the Bedourie Bore, 5 miles west of the area, and from Delhi-Frome-Santos Betoota No. 1 Well , 50 miles south of the Machattie area. A major north-east trending structure is present in the north-east corner of the area. It is possibly a continuation of the structure against which the Burke River Structure terminates in the Springvale 4-mile Sheet area, north of the Machattie area. No economic mineral deposits are present in the area

  • A history of geological events has emerged from the regional geological mapping of 35,000 square miles of the Cairns-Townsville Hinterland of North Queensland from 1956 to 1959.The hinterland consists of a broad Precambrian shield - the Georgetown Shield -which is 200 miles long and 150 miles wide, and flanked to the east by a Palaeozoic geosynclinal zone 50 to 150 miles wide, containing 40,000 feet of sediments. The geosynclinal zone is the northern part of the Tasman Geosynclinal Zone, which occupies most of the eastern coast of Australia. The shield and geosynclinal zones are intruded by igneous rocks: 20,000 square miles of acid and 5,000 square miles of basic and ultrabasic crop out. The decipherable history of the Georgetown Shield began early in the Precambrian (Archaean?) when its central region was depressed into deep crustal levels. Sediments deposited in the depression were regionally metamorphosed to granulite, amphibolite, and migmatite, and during the Middle Precambrian (Lower Proterozoic?) uplifted to form a geanticline. At the same time the western flank of the central geanticline was down-warped to form the Etheridge Geosyncline, in which a total thickness of 30,000 feet of sediments most pelagic, with lesser amounts of terrigenous and organic sediments, was deposited. Also during this uplift 15,000 feet of fine-grained quartz and calcareous detritus were deposited on its eastern flank in the Paddy's Creek area. The Precambrian history of the Shield terminated with the intrusion of the Forsayth Batholith into the core of the geanticline, and of ultrabasic rocks along its eastern fractured edge. Steep-angled thrusting of the Archaean metamorphics over the Lower Proterozoic sediments may have accompanied both these intrusions. After the Precambrian, the shield was uplifted and fractured extensively during the deformation of the Tasman Geosyncline.The Tasman Geosyncline in North Queensland contains a maximum thickness of 409000 feet of sediments ranging from Upper Ordovician? to Permian, which were deposited in a belt 270 miles long and averaging 100 miles wide. The deformation of the geosyncline began in the late Silurian with the uplift of amass of early Palaeozoic sediments in its central region, which divided the original depositional area into two parts. During this uplift serpentine and gabbro were intruded along the south-western fractured edge of the central tectonic land. The uplift of the tectonic land continued in the Devonian and Carboniferous, and was one of the major events that controlled sedimentation in the geosyncline; it forced the depositional areas to contract and migrate, resulting in the replacement of the early widespread marine sedimentation by restricted freshwater sedimentation. The geosyncline was further deformed by fracturing along the south-eastern edge of the Shield, which gave rise to a rift - the Broken River Rift. The last sediments in the hinterland were deposited during the late Carboniferous and Permian; immediately after this period the whole of the Tasman Geosyncline and the Georgetown Shield was land, and the shield continued to arch upwards. This arching resulted in extensive fracturing of the central region of the shield and its north-eastern edges. The fractures formed rift valleys and cauldron subsidence areas, which were occupied by rhyolite and ignimbrite, coeval and comagmatic with two ages of granite. The extrusion of continental olivine basalt in the Cainozoic near the eastern fractured shield edges was the final igneous episode of the history of the Cairns-Townsville Hinterland.

  • Cretaceous and Tertiary rocks are exposed over the total area of nearly 7,000 square miles. Surface and subsurface information reveals 6,000 feet of Mesozoic sediments and 30 feet of Tertiary rocks. The topmost beds are much weathered and silicified. In the south-east near Betoota there is a broad, elongate dome, and some minor structural trends to the west. A deep bore (9,824 feet) was drilled in the Betoota Dome in 1960 by Delhi-Frome-Santos, but failed to find economic quantities of oil or gas. The bore bottomed in steeply dipping red and green conglomerates of pre-Jurassic age. There is one artesian bore in the area, and several attempts to find supplies of sub-artesian water have been unsuccessful

  • In 1960, the Bureau of Mineral Resources, in association with the Geological Survey of Queensland, commenced a programme of regional mapping of the Bowen basin, Queensland. The primary aim of this programme was to assist the search for oil in the basin. Two parties were in the field during 1960. This progress report covers the work of one of these parties; the Mt.Coolon party, which mapped most of the Mt.Coolon 4-mile area.

  • Atherton 4-mile geological series Sheet E-55-5; explanatory notes.