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  • This folder contains the reports and supporting digital datasets from four geological studies published by SRK (later FrOGTech) consultants, between 2001 and 2007. Known as the OZ SEEBASE Compilation (Structurally Enhanced View of Economic Basement), the studies interpreted the three dimensional character of Australian sedimentary basins and their basement.

  • Plans for the National Geochemical Survey of Australia were presented to the geoscience agencies of all States and the Northern Territory in early 2007. The presentation entitled National Geochemical Survey of Australia: outline of a new proposal was given to: Primary Industries and Resources South Australia in Adelaide on 20 February 2007 Geological Survey of Western Australia in Perth on 21 February 2007 New South Wales Department of Primary Industries in Maitland on 29 March 2007 Geological Survey of Queensland in Brisbane on 2 May 2007 Northern Territory Geological Survey in Darwin on 3 May 2007 Minerals Resources Tasmania in Hobart on 16 May 2007 GeoScience Victoria in Melbourne on 17 May 2007

  • National Geochemical Survey of Australia field training for the geoscience agencies of all States and the Northern Territory took place during 2007 and early 2008. The knowledge transfer mechanisms comprise a detailed National Geochemical Survey of Australia: Field Manual (GA Record 2007/08), this training presentation and several days of in-field sample collection under the guidance of NGSA staff.

  • Image showing gravity station coverage over Australia, updated to October, 2007

  • The 2002 report to the Council of Australian Governments (COAG) <i>Natural disasters in Australia: Reforming mitigation, relief and recovery arrangements</i> advocated a 'fundamental shift in focus towards cost-effective, evidence-based disaster mitigation'. The report stated that in Australia there was a 'lack of independent and comprehensive systematic natural disaster risk assessments, and natural disaster data and analysis'. One key solution proposed to address this gap in our knowledge is outlined in Reform Commitment 1 in the report: <i>Develop and implement a five-year national programme of systematic and rigorous disaster risk assessments</i>. This framework is designed to improve our collective knowledge about natural hazard risk in Australia to support emergency risk management and natural hazard mitigation. The natural hazards covered are those defined in the report to COAG: bushfire, earthquake, flood, storm, cyclone, storm surge, landslide, tsunami, meteorite strike and tornado. Many events have demonstrated that the importance of natural hazards does not lie simply in the generation and passage of events such as severe storms or floods, but in the wide-reaching and profound impacts that these events can have on communities. Risk 1 is defined as: A concept to describe the likelihood of harmful consequences arising from the interaction of hazards, communities and the environment. This framework focuses on risk assessment for sudden onset natural hazards to underpin natural hazard risk management and natural hazard mitigation. The framework does not focus on risk management or mitigation, although its outcomes support and benefit these. The framework covers the following risks arising from natural hazards: financial, socio-economic, casualty, political and environmental risk. Each of these risks contributes to the overall impacts of natural hazards on communities . This framework is aimed foremost at those who seek an improved evidence base for risk management of natural hazards, in all levels of government. The framework is also intended for risk assessment practitioners, researchers and information managers. The primary driver of the framework is the need to develop an improved evidence base for effective risk management decisions on natural hazards. Developing this improved evidence base will also deliver on COAG Reform Commitment 1. Other key drivers include: - Cooperative approaches across all levels of government to managing natural hazards; - A consistent approach to natural hazard risk assessment; - Risk management for cross-jurisdictional and catastrophic disasters; - The potential impacts of climate change from possible changes in the frequency or severity of weather related natural hazards; - Increasing exposure of populations to natural hazards through demographic change and increases in personal assets.

  • The eastern Gawler craton hosts Australia's premier uranium-bearing iron oxide copper-gold (IOCG) belt, the >500-km-long Olympic Cu-Au-(U) province. In addition to the Olympic Dam Cu-U-Au and Prominent Hill Cu-Au deposits, numerous barren and weakly mineralized IOCG prospects are present in the province. New geochronological data for hydrothermal minerals combined with constraints from host-rock ages demonstrate that alteration and associated IOCG mineralization formed between ~1570 and ~1600 Ma in three districts of the province. This IOCG hydrothermal activity temporally overlaps with magmatism of the Hiltaba Suite and Gawler Range Volcanics. Titanites in paragenetically early magnetite-bearing alteration in the Olympic Dam and Prominent Hill districts yield U-Pb ion probe ages of 1576 ± 5 and 1567 ± 10 Ma, respectively. Molybdenite in veins crosscutting magnetite-biotite and albitic alteration in the Moonta-Wallaroo district have Re-Os ages of 1574 ± 6 and 1599 ± 6 Ma, respectively. These represent minimum ages of the IOCG alteration assemblages in this district. A muscovite 40Ar/39Ar age of 1575 ± 11 Ma provides a minimum age of paragenetically later hematitic alteration in the Olympic Dam district. Neodymium isotope compositions were determined for 44 whole-rock samples from barren and weakly mineralized Cu-Au prospects and host rocks in the Olympic Dam and Prominent Hill districts. The new geochronological framework enables comparison of the Nd isotope data across two IOCG districts at the time of formation of the Olympic Dam deposit (ca. 1590 Ma). Magnetite-rich weakly Cu-mineralized alteration from five prospects yields a relatively narrow range of {varepsilon}Nd(1590) values of -5.8 to -4.1. Both hematite- and magnetite-rich alteration yield generally similar {varepsilon}Nd(1590) values that match values from fresh and weakly altered Paleoproterozoic metasedimentary and metagranitic rocks (-6.6 to -3.5) as well as from most felsic Hiltaba Suite intrusions and Gawler Range Volcanics in the eastern Gawler craton (ca. -6 to -4). These data are consistent with crustal sources for REE and, by implication, for associated copper in the barren and weakly mineralized prospects. Mineralization and alteration in these minor IOCG systems can be geochemically discriminated from the giant Olympic Dam deposit, where greater inputs of mantle-derived REE and other ore components are evident.

  • During the late Neogene, the Lambert Glacier-Amery Ice Shelf drainage system flowed across Prydz Bay and showed several changes in flow pattern. In the Early Pliocene, the Lambert Glacier ice stream reached the shelf edge and built a trough mouth fan on the upper continental slope. This was associated with an increase in ice discharge from the Princess Elizabeth Land coast into Prydz Bay. The trough mouth fan consists mostly of debris flow deposits derived from the melting out of subglacial debris at the grounding line at the continental shelf edge. The composition of debris changes at around 1.1 Ma BP from material derived from erosion of the Lambert Graben and Prydz Bay Basin to mostly basement derived material. This probably results from a reduction in the depth of erosion and hence the volume of ice in the system. In the trough mouth fan, debris flow intervals are separated by thin mudstone horizons deposited when the ice had retreated from the shelf edge. Age control in an Ocean Drilling Program hole indicates that most of the trough mouth fan was deposited prior to the Brunhes Matuyama Boundary (780 ka BP). This stratigraphy indicates that extreme ice advances in Prydz Bay were rare after the mid Pleistocene, and that ice discharge from Princess Elizabeth Land became more dominant than the Lambert Glacier ice in shelf grounding episodes, since the mid Pleistocene. Mechanisms that might have produced this change are extreme inner shelf erosion and/or decreasing ice accumulation in the interior of East Antarctica. We interpret this pattern as reflecting the increasing elevation of coastal ice through time and the increasing continentality of the interior of the East Antarctic Ice Sheet. The mid Pleistocene change to 100 ka climatic and sea level cycles may also have affected the critical relationship between ice dynamics and the symmetry or asymmetry of the interglacial/glacial climate cycle duration.

  • Multichannel seismic data collected off Wilkes Land (East Antarctica) reveal four main units that represent distinct phases in the evolution of the Cenozoic depositional environment. A Cretaceous synrift succession is overlain by hemipelagic and distal terrigenous sequences deposited during Phase 1. Sediment ridges and debris-flow deposits mark the transition to Phase 2. Unit 3 records the maximum sediment input from the continent and is characterized by the predominance of turbidite deposits. During Phase 4 the sediment supply from the continental margin was reduced, and draping and filling were the dominant processes on the continental rise. Unit 4 also contains the deposits of sediment wave fields and asymmetric channel-levee systems. These four units are a response to the Cenozoic evolution of the East Antarctic Ice Sheet. During Phase 1, small ice caps were formed in the innermost continental areas. The ice volume increased under temperate glacial regimes during Phases 2 and 3, when large volumes of melt-water production led to high sediment discharge to the continental rise. Change to a polar regime occurred through Phase 4, when a thick prograding wedge developed on the continental shelf and slope and the sediment transport to the rise diminished, producing general starvation conditions.

  • Close up map, 1:63 000, produced for ACMA, of Submarine Cable and Southern Protection Zone around Clovelly & Tamarama, Sydney. Includes Charter boat Anchoring sites related to The Peak Anchoring Zone and other fishing spots provided. For internal use by ACMA.

  • Direct dating of ore minerals: A feasibility study of the Pb-Pb isotope step-leaching technique