No abstract available

The Perth 1:1M sheet covers an area underlain by Archaean rocks of the western Yilgarn Craton, adjacent, abutting or onlapping Proterozoic rocks such as the Northampton Block, and Phanerozoic rocks of the Perth Basin. The aeromagnetic interpretation provides most information on the distribution of Archaean rocks as these rocks are generally moderately to highly magnetised with reasonable variation of magnetisation. Adjacent Perth Basin sediments are poorly magnetised and spatially associated magnetic anomalies are attributed to underlying Proterozoic rocks. The Archaean rocks are subdivided into undivided gneiss-migmatite-granite (Agmg), banded gneiss (Agn), sinuous gneiss (Anu), greenstone (Aa), and granite plutons (Ag). Where important relative differences in magnetisation are mapped, the geophysical map units include the suffixes _h (high), _m (medium), _l (low) and _r (remanent) for the level of magnetisation. Dykes, faults, and unassigned small intrusives are also mapped. Large Archaean domains equivalent to geologically defined Provinces are also defined including Murchison, Toodyay- Lake Grace, Southwest, Southern Cross and Yeelirrie domains. The map is complemented by the inclusion of selected mineral deposits

The Treasure Mine, Hatches Creek, is believed to have been discovered in 1914 and has been one of the most consistent producers of wolfram to the present time. This report gives an account of the economic geology of the mine. The ore type, reefs and workings, ore localization, and ore reserves are described.

Sandstone uranium mineral systems

- Although exploration is languishing at a 20 year low, the outlook is the best for five years. - Metal prices are forecast to improve over the next several years. - Australia remains highly prospective and discoveries continue to be made both in proven and greenfields provinces. - Exploration in the past 10 years has added significant resources - notably gold, nickel, mineral sands, tantalum - at low cost. - Major potential exists undercover. - As a result of Government programs over the past decade, a wealth of geoscience data is available either free or at very low cost. These are playing an important role in opening up the under explored frontier provinces to exploration.

Lower Proterozoic sedimentary, metamorphic, and igneous rocks of the Pine Creek Geosyncline and Nimbuwah Complex form the basement rocks of the Bathurst Terrace. To the west of the Bathurst Terrace, along the eastern edge of the adjoining Bonaparte Gulf Basin, Phanerozoic sedimentation commenced in the Early Permian and led to the accumulation of a conformable sequence comprising the Kulshill, Hyland Bay, and Mount Goodwin Formations, and an unnamed Middle to Upper Triassic formation. It was not until the Late Jurassic that the sea transgressed onto the Bathurst Terrace to deposit the Petrel Formation, followed by the Bathurst Island Formation in the Cretaceous, and the Van Diemen Sandstone in the Early Tertiary. In the Late Cretaceous and Tertiary, chemical weathering produced an extensive cover of laterite. Mineral sands containing ilmenite, zircon, and rutile occur along the northern and western coasts of Bathurst and Melville Islands. Uneconomical deposits of bauxite crop out on the northern headlands of Cobourg Peninsula and Croker Island. In addition, uneconomical deposits of uranium, manganese, phosphate, limestone, clay, and hydrocarbons have been found in the area. Subartesian water is available on Bathurst and Melville Islands from aquifers in the Van Diemen Sandstone, and artesian water was discovered in the Marligur Member of the Bathurst Island Formation in the southern Cobourg Peninsula Sheet area.

This is a public domain release of the Module 3 structural study from the Predictive Mineral Discovery Co-Operative Research Centre (pmd*CRC) and AMIRA (Australian Mineral Industry Research Association) Y1-P763 project which concluded in November 2005. An 18 month confidentiality period applied to this work but the resulting report is now able to be released. Research into the structural evolution of the Eastern Goldfields Superterrane (EGST) continued in allied projects (Y2 and Y4) as part of the pmd*CRC program. The Y2 project Final Report was released to the public as Geoscience Australia Record 2006/05. As of July 2007, the active Y4 pmd*CRC project has been continuing the work from the Y1-P763 and Y2 projects. Therefore, some interpretations of the structure of the EGST presented in Geoscience Australia Record 2007/15 have changed. One of the enduring assets of the original Y1-P763 Final Report is the very extensive data preserved in the appendices, which, due to their size, are available only on DVD. The philosophy behind the Y1-P763 report was to clearly separate data from interpretation, a move which has aided continuous improvement in the understanding of the structural evolution of the EGST. No structural difference between terranes. The only possible terrane accretion structures are the Ida and the Hootanui since the Ockerburry is extensional. No D1 N-S compression, early isoclinal shallowly dipping structures are interpreted to be extensional in origin. Long-lived ENE-directed extension marked during D1 which formed the major basin architecture for the greenstone sequences. There is a strong extensional event (D3) which postdates D2 compression and forms and deforms the late basins. The crustal architecture (observed in seismic) is controlled by D1 and D3 extension. It is not a thin-skinned fold and thrust belt. The NNW-trending tectonic grain in the Eastern Yilgarn was set up as a result of ENE-directed D1 and D3 extension with local extension vectors controlled by the exhumation of granite domes in the footwall to NNW striking extensional shear zones. The folding which the late basins unconformably overlay may have formed during extension. Further work is required to examine is this hypothesis holds true for every case not just around the Lawlers Anticline. The N-S tectonic grain in the Eastern Yilgarn is a function of D2 and D5 dextral transpression which has dissected the NNW-trending extensional architecture. D2 and D3 are spatially inversely related, i.e. where D2 is present D3 is absent and where D3 is present D2 is absent. This poses the question as to the significance or pervasiveness of the D2 contractional deformation. P-T dihedra work has resolved D2 and D5, B1B palaeostress to be predominantly ENE- to NE-striking. Contractional deformation is predominantly associated with strike-slip movement on N- to NNW-striking faults as opposed to thrusts. This study has recognised a N-S to NW-SE oriented low-strain contractional D4 deformation event. This deformation is typically expresses as either sinistral N- to NNW striking faults or E-W striking N- and S-directed thrusts. Few events have the structural style and intensity necessary for significant crustal thickening. This study recognised that gold is present in extensional structures although the majority of Au deposits lay in contractional structures. Gold deposits located in ductile shear zones are typically localised in the highest strain regions of the shear zone typically located at its centre. These high strain areas are typically marked by the presence of shear related foliation boudinage.

Australia's thorium resources currently amount to 452,000tonnes Th of which 364,000tonnes (80.5%) occur in heavy mineral sand deposits, 53,300tonnes (11.7%) in a vein type deposit at Nolans Bore in the Northern Territory and another 35,000tonnes (7.7%) are in an alkaline trachyte plug at Toongi in New South Wales. This distribution of thorium resources differs from the world wide distribution where 31.3% of the resources occur in carbonatites, 24.6% are in placers, 21.4% in vein type deposits and 18.4% in alkaline rocks. This variance is at least partly due to relatively more, although still inadequate, data on thorium resources being generated by the very active heavy mineral sand operations around Australia. Even where thorium analyses have been carried out for other types of deposits that host thorium, such results are not published since thorium is not considered to be economically important. All of Australia's thorium resources occur in multi-commodity deposits, dominantly the heavy mineral sands and in rare earth deposits where the extraction cost would be shared with if not totally supported by the other commodities in the deposit. Because there has been no large-scale demand for thorium, there has been little incentive for companies to assess the cost for the extraction of thorium resources. Hence there is insufficient information to determine how much of Australia's thorium resources are economic for purposes of electricity power generation in thorium nuclear reactors. Geoscience Australia is currently engaged in upgrading its database on thorium resources as part of the five-year Onshore Energy Security Program and Australia's figures on its thorium resources will be refined as a result of this work. Because of limited demand, there has been very little exploration for thorium in Australia. As part of its five year Onshore Energy Security Program, Geoscience Australia is in process of upgrading its continent wide airborne radiometric coverage and is conducting a low density geochemical sampling program across the continent. These programs will help to develop a better understanding of the geological and geochemical environment of thorium in Australia and provide basic pre-competitive data to reduce risk the level of risk for the mineral exploration industry. Assessment of thorium resources by the minerals industry in the future will depend upon the development of commercial-scale thorium nuclear reactors and the resulting demand for thorium resources.

Global gold resource endowment of geological regions in Australia based on aggregate past gold production and current resources.

This record describes digital data compilation product, where several individual items are grouped for delivery on single CD-ROM. Content and number of items included in the compilation package can vary, depending on size of the individual items. The contents of this CD-ROM are as follows: Catalog # Title 34192 OZMIN national mineral deposits dataset with documentation 33468 OZMIN national mineral deposits documentation Record 2000/18 34735 Mineral Occurrence Location Database (MINLOC), digital package including documentation