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  • Basin evolution of the Vlaming Sub-basin and the deep-water Mentelle Basin, both located offshore on the southwest Australian continental margin, were investigated using 2D and 3D petroleum system modelling. Compositional kinetics, determined on the main source sequences, were used to predict timing of hydrocarbon generation and migration as well as GOR evolution and phase behaviour in our 2D and 3D basin models. The main phase of petroleum generation in the Vlaming Sub-basin occurred at 150 Ma and ceased during following inversion and erosion episodes. Only areas which observed later burial have generated additional hydrocarbons during the Tertiary and up to present day. The modelling results indicate the likely generation and trapping of light oils for the Jurassic intervals for a variety of structural traps. It is these areas which are of greatest interest from an exploration point of view. The 2D numerical simulations in the Mentelle Basin indicate the presence of active hydrocarbon generating kitchen areas. Burial histories and generalized petroleum evolutionary histories are investigated.

  • 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.

  • 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 structural controls of gold mineralisation within the Bardoc tectonic zone, Eastern Goldfields province, Western Australia; implications for gold endowment in shear systems. Mineralium Deposita, 42(6), 583-600.

  • This ALOS processed data covers the area from Newcastle down to Batemen's Bay on the east coast of New South Wales for Geoscience Australia. The data has been delivered in a number of both tile and mosaic files. The data delivered to Geoscience Australia consists of 8 AVNIR scenes and 13 triplet PRISM scenes.

  • Datasets of wind speed purchased from BoM to develop Record 2007/12

  • Geologic observations suggest two stages of hydrothermal activity at a number of presently subeconomic iron oxide copper-gold systems in the Olympic Dam district, eastern Gawler craton. They contain high-, and moderate- to low-temperature Fe oxide-rich hydrothermal alteration. The mineral assemblages include magnetite-calc-silicate-alkali feldspar ± Fe-Cu sulfides and hematite-sericite-chlorite-carbonate ± Fe-Cu sulfides ± U, REE minerals. In all documented prospects, the minerals of the hematitic assemblages replace the minerals of the magnetite-rich assemblages. The bulk of the subeconomic Cu-Au mineralization is associated with the hematitic alteration assemblages. Microanalysis by proton ion probe (PIXE) of hypersaline fluid inclusions in magnetite-rich assemblages, however, demonstrates that significant amounts of copper (>500 ppm) were transported by the early-stage high-temperature (>400C) fluids responsible for the magnetite-rich alteration. These brine inclusions contain multiple solid phases (liquid + vapor + multiple solids) including chalcopyrite in some cases. In comparison, inclusions of the hematitic stage are relatively simple liquid + vapor types, with homogenization temperatures of 200C to 300C and containing 1 to 8 wt percent NaCl equiv. The Br/Cl ratios of the magnetite-forming fluids measured by PIXE lie beyond the range of typical magmatic and/or mantle values, allowing for the possibility that the fluids originated as brines from a sedimentary basin or the crystalline basement. Sulfur isotope compositions of chalcopyrite and pyrite demonstrate that sulfur in both alteration assemblages was derived either from cooling magmas and/or crystalline igneous rocks carried by relatively oxidized fluids ({sum}SO42- {approx} {sum} H2S, {delta}34Ssulfides from +5 to +2{per thousand}) or from crustal sedimentary rocks ({delta}34Ssulfides from +5 to +10{per thousand}). Oxygen and hydrogen isotope compositions of waters calculated for minerals of the magnetite-rich assemblage have {delta}18O values of +7.7 to +12.8 per mil and {delta}D values of +15 to +21 per mil. The only available {delta}18O and {delta}Dfluid values for the hematitic assemblage are +4.7 and +9 per mil, respectively. The isotopic compositions of both fluids, coupled with the available literature data, can be explained in terms of fluid reequilibration with felsic Gawler Range Volcanics or other felsic igneous rocks in the region and with metasedimentary rocks of the Wallaroo Group at low water-to-rock ratios prior to their arrival at the mineralization sites. The lack of significant copper mineralization associated with magnetite-forming fluids that carried copper suggests that there was no effective mechanism of saturation of copper minerals or the quantity of these fluids was not sufficient to produce appreciable copper mineralization. Association of the copper-gold mineralization with the hematitic alteration in the subeconomic prospects can be explained by a two-stage model in which preexisting hydrothermal magnetite with minor associated copper-gold mineralization was flushed by late-stage oxidized brines that had extensively reacted with sedimentary or metamorphic rocks. The reduction of these brines, driven by conversion of magnetite to hematite, resulted in precipitation of copper and gold. The oxidized brines may have contributed additional copper and gold to the system in addition to upgrading preexisting subeconomic Cu-Au mineralization. When compared to published models for the Olympic Dam deposit, the new data for fluids in subeconomic Fe-oxide Cu-Au prospects of the Olympic Dam district indicate the diversity of origins of iron oxide-copper-gold systems, even within the same geologic region.

  • This report describes the iterative methods used to create the seascapes, including a detailed appendix documenting the different datasets used in the different planning zones. Creating the seascapes is necessarily an iterative process whereby the available datasets are combined in different combinations, or added as they become available, using an unsupervised 'crisp' ISOClass classification in ERMapper. In each classification only biophysical properties that have consistent and definable relationships with the benthic biota and are known in sufficient detail across Australia's entire marine region are used to create the seascapes. An initial validation of the classification technique has been undertaken on a subset of the data for the shelf surrounding Tasmania using an alternative unsupervised 'fuzzy' classification. Results of this validation indicate that the unsupervised classification methodology provides consistent and reliable classes for defining the seascapes.

  • Tunkillia Deposit Scale Modelling: Predictive Targeting Outcomes predictive mineral discovery CRC -PIRSA 2- Minotaur Numerical Modelling Project -Update #2

  • Tunkillia Deposit Scale Modelling: Predictive Targeting Outcomes predictive mineral discovery CRC - PIRSA 2 - Minotaur Numerical Modelling Project Update #1