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  • Australian Governments over the past decade have acquired thousands of kilometres of high-quality deep-seismic reflection data. The deep-seismic reflection method is unique among imaging techniques in giving textural information as well as a cross sectional view of the overall crust, including the character of the middle crust, lower crust, Moho, and any upper mantle features. Seismic reflection data can be readily integrated with other geophysical and geological data to provide an unsurpassed understanding of a region's geological history as well as the mineral and energy resource potential. Continental Australia is made up of four main elements (blocks), separated by orogens. Most boundaries between the elements are deeply rooted in the lithosphere, and formed during amalgamation of Australia. Major boundaries within the elements attest to their individual amalgamation, mostly prior to the final construction of the continent. Many of Australia's mineral and energy resources are linked to these deep boundaries, with modern seismic reflection providing excellent images of the boundaries. All of the seismic surveys have provided new geological insights. These insights have significantly advanced the understanding of Australian tectonics. Examples include: preservation of extensional architecture in an otherwise highly shortened terrane (Arunta, Yilgarn, Mt Isa and Tanami), unknown deep structures associated with giant mineral deposits (Olympic Dam, Yilgarn, Gawler-Curnamona), as well as the discovery of unknown basins, sutures and possible subduction zones (Arunta, North Queensland, Gawler-Curnamona). These new insights provide not only an improved tectonic understanding, but also new concepts and target areas for mineral and energy resources.

  • The National Geochemical Survey of Australia (NGSA) project aims to provide pre-competitive data and knowledge to support exploration for energy resources in Australia (www.ga.gov.au/ngsa) and is part of Geoscience Australia's Onshore Energy Security Program. The NGSA project, which is carried out in collaboration with the geological surveys of all States and the Northern Territory, will deliver the nation's first geochemical atlas, a comprehensive geochemical database and preliminary reports when it concludes in June 2011. Catchment outlet sediments (similar to floodplain sediments in most cases) were sampled during 2007-2009 near the outlet of 1186 catchments covering ~80% of the country (average sample density 1 sample per 5500 km2). Samples were collected at two depths: 0-10 cm below the surface (top outlet sediment, TOS) and between on average 60 and 80 cm depth (bottom outlet sediment, BOS). Samples were dried and sieved to either <2 mm (coarse) or <75 mm (fine) fractions, yielding four samples per site. The geochemical data presented here is from total element content analysis by x-ray diffraction after lithium borate fusion (for potassium) and collision cell inductively coupled plasma-mass spectrometry after lithium borate fusion followed by hydrofluoric and nitric acid digestion (for thorium and uranium). (.../... truncated)

  • Inspections were made of the Burra, Kapunda, Wallaroo, Moonta, Hamley, and Kanmantoo Copper Mines, and a number of smaller mines on the outskirts of the main mining centres. There follows a review of each of the areas in the order visited.

  • Overview of general work, sampling, mapping and levelling, drafting, and laboratory work carried out during the month of September, 1947.

  • Fluids in mineral systems may be derived from above, within, or below the Earth's crust. Fluid production rates and observed Cl contents indicate that the dominant inputs to mineral systems are surface derived (meteoric & bittern) waters and those transported into the crust from below, principally by magmas. These conclusions can be used as part of any analysis of the distribution of mineral systems and ore deposits.

  • The possibilities of finding evaporite deposits in Queensland were investigated by C.L. Knight and E.K. Sturmfels on a reconnaissance trip from 10th July until 5th August, 1949. The localities where indications of evaporite deposits were found or from which they are reported, are classified on the following pages according to the geological formations, and their position is shown on the accompanying map.

  • The basin-scale density of uranium (tonnes of U3O8 per square Kilometre of the basin) shows that some basins are characterised by very high endowment. These include Bohemia Basin in Czech Republic (density of 12.7); San Juan Basin in USA (density of 11.1) and Chu-Sarysu and Syrdarya basins, Kazakhstan (density of 6.2). The uranium density in other poorly endowed basins varies between 2.5 and 0.03. This paper reviews the architecture of the hydrothermal system in the three highly-endowed basins and compares it with those of the basins that are not so well endowed. The architecture is analysed in terms of the following critical components: - shape of the basin at the time of mineralisation - the nature and position of the uplifted highland areas that could have served as the first-stage and/or immediate source of uranium - tectonic activity along faults located at the basin margin and in the basin - permeability of sedimentary sequence - presence of in-situ and/or introduced reductant (organic and inorganic) - age and frequency of mineralising events The analysis shows that although the presence of readily leachable source of uranium is an important constraint, giant sandstone-uranium basins require an architecture that maintains sustained fluid-flow through the aquifer. Availability of relatively more mobile reductant (hydrocarbon gases) is also important because it ensures effective entrapment of uranium from the fluids.

  • Uranium exploration expenditure in Australia has increased progressively since 2003 mainly because of the significant increases in spot market uranium prices in recent years. In 2007-08, uranium exploration expenditure increased to a record level of $231.6 million , which is approximately double the 2006-07 expenditure ($111.4 million). The majority of expenditure was in South Australia (51%), followed by the Northern Territory (21%), Queensland (16%) and Western Australia (12%). Uranium exploration expenditure in the 2008 September quarter ($56.7 million) was above the 2007 September quarter ($50 million). However the difference is the expenditure trend from the June quarter to the September quarter, in 2007 expenditure grew by $6.7 million whereas in 2008 expenditure reduced by $6.0 million. This reduction may reflect that the current global economic crisis is affecting the level of uranium exploration spending. Geoscience Australia prepares annual estimates of Australia's uranium resources within categories used for international reporting by the Uranium Group (a joint initiative of the OECD Nuclear Energy Agency and the International Atomic Energy Agency). The estimates are for resources of recoverable uranium after losses due to mining and milling have been deducted. As of December 2008, Australia's Reasonably Assured Resources (RAR) recoverable at costs of <US$80/kg U were estimated to be 1,111,000 t U. This represents an increase of 12% over the estimates for the previous year, mainly due to large increase in both reserves and resource estimates for Olympic Dam deposit (South Australia) and transfer of resources from Inferred in RAR. This means Australia's share of the world's total RAR of uranium recoverable at <US$80/kg U has increased to about 37% . <truncated>

  • In 1999, Australia's economic demonstrated resources (EDR) of bauxite, diamond, gold, iron ore, manganese ore, magnesite, mineral sands (ilmenite, rutile, and zircon), nickel, phosphate rock and tantalum rose, while those of copper, coal (black and brown), lead, lithium, silver, uranium and zinc fell. The reductions in EDR were due mainly to ongoing high levels of production; commodity prices were a subsidiary factor. EDR of all other commodities remained effectively unchanged. EDR of bauxite and manganese ore increased by 16% and over 22% respectively, following reviews of resources information that became available during the year. Increases in EDR of both gem/near gem and industrial diamond resulted from delineation of additional resources in Western Australia. EDR of nickel and tantalum again reached record levels. Gold increased by 14%, surpassing the previous EDR high established in 1996. Australia continues to rank highly as one of the world's leading mineral resource nations. It has the world's largest EDR of lead, mineral sands, nickel, silver, tantalum, uranium and zinc. In addition, its EDR is in the top six worldwide for bauxite, black coal, brown coal, copper, cobalt, copper, gold, iron ore, lithium, manganese ore, rare earth oxides, gem/near gem diamond and vanadium.