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  • <div>The National Geochemical Survey of Australia (NGSA) is Australia’s only internally consistent, continental-scale geochemical atlas and dataset. The present dataset contains additional mineralogical data obtained on NGSA samples selected from the Barkly-Isa-Georgetown (BIG) region of northeastern Australia for the second partial data release of the Heavy Mineral Map of Australia (HMMA) project. The HMMA project, a collaborative project between Geoscience Australia and Curtin University underpinned by a pilot project establishing its feasibility, is part of the Australian Government-funded Exploring for the Future (EFTF) program.</div><div>One-hundred and eighty eight NGSA sediment samples were selected from the HMMA project within the EFTF’s BIG polygon plus an approximately one-degree buffer. The samples were taken on average from 60 to 80 cm depth in floodplain landforms, dried and sieved to a 75-430 µm grainsize fraction, and the contained heavy minerals (HMs; i.e., those with a specific gravity > 2.9 g/cm3) were separated by dense fluids and mounted on cylindrical epoxy mounts. After polishing and carbon-coating, the mounts were subjected to automated mineralogical analysis on a TESCAN® Integrated Mineral Analyzer (TIMA). Using scanning electron microscopy and backscatter electron imaging integrated with energy dispersive X-ray analysis, the TIMA identified 151 different HMs in the BIG area. The dataset, consisting of over 18 million individual mineral grains, was quality controlled and validated by an expert team. The data released here can be visualised, explored and downloaded using an online, bespoke mineral network analysis (MNA) tool built on a cloud-based platform. Preliminary analysis suggests that copper minerals cuprite and chalcopyrite may be indicative of base-metal/copper mineralisation in the area. Accompanying this report are two data files of TIMA results, and a minerals vocabulary file. </div><div>When completed in 2023, it is hoped the HMMA project will positively impact mineral exploration and prospectivity modelling around Australia, as well as have other applications in earth and environmental sciences.</div>

  • <div>The Petroleum Systems Summary database stores the compilation of the current understanding of petroleum systems information by basin across Australia. The Petroleum Systems Summary database and delivery tool provide high-level information of the current understanding of key petroleum systems for areas of interest. For example, geological studies in the Exploring for the Future (EFTF) program have included the Canning, McArthur and South Nicholson basins (Carr et al., 2016; Hashimoto et al., 2018). The database and tool aim to assist geological studies by summarising and interpreting key datasets related to conventional and unconventional hydrocarbon exploration. Each petroleum systems summary includes a synopsis of the basin and key figures detailing the basin outline, major structural components, data availability, petroleum systems events chart and stratigraphy, and a précis of the key elements of source, reservoir and seal. Standardisation of petroleum systems nomenclature establishes a framework for each basin after Bradshaw (1993) and Bradshaw et al. (1994), with the source-reservoir naming conventions adopted from Magoon and Dow (1994).&nbsp;</div><div><br></div><div>The resource is accessible via the Geoscience Australia Portal&nbsp;(https://portal.ga.gov.au/) via the Petroleum Systems Summary Tool (Edwards et al., 2020).</div>

  • <div>A regional hydrocarbon prospectivity assessment has been undertaken of the offshore Otway Basin by the Offshore Energy Systems Section. This program was designed to produce pre-competitive information to assist with the evaluation of the hydrocarbon resource potential of the offshore Otway Basin and attract exploration investment to Australia. The inboard part of the basin is an established hydrocarbon province with onshore and shallow-water offshore discoveries, whereas the outboard deep-water region, where water depths range from 500 to 6300&nbsp;m, is comparatively underexplored and considered a frontier area.</div><div><br></div><div>As part of this program, molecular and noble gas isotopic analyses were undertaken by Smart Gas Sciences, under contract to Geoscience Australia on available gas samples from the Waarre Formation in the Shipwreck Trough in the offshore eastern Otway Basin, with data from these analyses being released in this report. This report provides additional compositional information for gases in the Waarre Formation reservoirs and builds on previously established gas-gas correlations and gas-oil correlations. Noble gas isotopic data can be used in conjunction with carbon and hydrogen isotopic data to determine the origin of both inorganic and organic (hydrocarbon) gases. This information can be used in future geological programs to determine the source and distribution of hydrogen and helium in natural gases and support acreage releases by the Australian Government.</div><div><br></div><div><br></div>

  • <div>As a resource to enhance exploration in the offshore Otway Basin, Geoscience Australia (GA) has produced a new well folio that extends the scope of a previous release by including 32 key wells from the central and southeast regions. This folio covers the areas from Normanby 1 on the Normanby Terrace, through the Shipwreck Trough and Nelson Sub-basin, to Whelk 1 in the south. The previous well composites included wireline logs for petrophysical analysis, interpreted lithology, organic geochemistry and organic petrology data, and well markers. This folio includes all of these attributes with the addition of core-based depositional environment (DE) and gross depositional environment (GDE) interval interpretations which were subsequently used to constrain wireline interpretation away from core control. The core/wireline lithological interpretation along with further seismic and biostratigraphic data informed well marker locations and enabled a better regional correlation across the basin. The folio provides the complementary datasets used to construct each well composite. Presented at the Australian Energy Producers (AEP) Conference & Exhibition (https://energyproducersconference.au/conference/)

  • <div><strong>Conclusions</strong>&nbsp;</div><div><br></div><div>The NW NT Seismic Survey (L214) was designed to image the underexplored Proterozoic Birrindudu Basin and adjacent regions, including the highly prospective Tanami region. In an area of very limited seismic coverage, the acquisition of ~900km of deep crustal seismic data has vastly improved the seismic coverage through this region. &nbsp;The new dataset will be available as both raw and processed data files from the Geoscience Australia website in the future.</div><div><br></div>Abstract presented at the 2024 Annual Geoscience Exploration Seminar (AGES)

  • <div>This study was commissioned by Geoscience Australia (GA) to produce a report on seal capacity of select samples from the deep stratigraphic hole NDI Carrara 1, located in the Proterozoic Carrara Sub-basin in the Northern Territory. Plugs were taken from depths of interest and analysed via mercury injection capillary pressure testing. Results were provided as two reports, Part A and Part B and demonstrate that the analysed samples are capable of sealing very large columns of both methane and carbon dioxide.</div>

  • <div>The architecture of the lithosphere controls the distribution of thermal, compositional and rheological interfaces. It therefore plays a fundamental role in modulating key ore-forming processes including the generation, transport, fractionation, and contamination of melts.&nbsp;Recognition of its importance has led to renewed efforts in recent years to incorporate constraints on lithospheric structure into the targeting of prospective regions for mineral exploration. One example is a suggested relationship between the genesis of porphyry copper deposits – known to be associated with evolved, silica-rich magmas – and the thickness of the crust.&nbsp;Here, using a new compilation of spot measurements, we explore the utility of crustal thickness as an exploration tool for porphyry copper deposits.</div> This Abstract was submitted & presented at the 2022 American Geophysical Union (AGU) Fall Meeting 12-16 December (https://www.agu.org/Fall-Meeting-2022)

  • <div>A keynote talk talk given at Uncover Curnamona 2022 by Angela O'Rourke outlining the rationale, work program and new data acquisition for Geoscience Australia's Darling-Curnamona-Delamerian Project within Exploring for the Future</div> This presentation was given to the 2022 Uncover Curnamona 2022 Conference 31 May - 2 June:<br>(https://www.gsa.org.au/common/Uploaded%20files/Events/Uncover%20Curnamona%202021/UC2022_short_program_A4_web%20(003).pdf)

  • <div>The Canning Basin is a prospective hydrocarbon frontier basin and is unusual for having limited offshore seismic and well data in comparison with its onshore extent. In this study, seismic mapping was conducted to better resolve the continuity of 13 key stratigraphic units from onshore to offshore to delineate prospective offshore hydrocarbon-bearing units, and better understand the distribution of mafic igneous units that can compartmentalise migration pathways and influence heat flow. The offshore Canning Basin strata are poorly constrained in six wells with limited seismic coverage; hence data availability was bolstered by integrating data from the onshore portion of the basin and adjacent basins into a single 3D seismic stratigraphic model. This model integrates over 10 000 km of historical 2D seismic data and 23 exploration wells to allow mapping of key stratal surfaces. Mapped seismic horizons were used to construct isochores and regional cross-sections. Seven of the 13 units were mapped offshore for the first time, revealing that the onshore and offshore stratigraphy are similar, albeit with some minor differences, and mafic igneous units are more interconnected than previously documented whereby they may constitute a mafic magmatic province. These basin-scale maps provide a framework for future research and resource exploration in the Canning Basin. To better understand the basin’s geological evolution, tectonic history and petroleum prospectivity, additional well data are needed in the offshore Canning Basin where Ordovician strata have yet to be sampled.</div><div><br></div><div>C. T. G. Yule, J. Daniell, D. S. Edwards, N. Rollet & E. M. Roberts&nbsp;(2023).&nbsp;Reconciling the onshore/offshore stratigraphy of the Canning Basin and implications for petroleum prospectivity,&nbsp;Australian Journal of Earth Sciences,&nbsp;DOI:&nbsp;10.1080/08120099.2023.2194945</div> Appeared in Australian Journal of Earth Sciences Pages 691-715, Volume 70, 2023 - Issue 5.

  • High-purity quartz (HPQ) is the only naturally occurring and economically viable source for the production of silicon. Silicon is a critical mineral, and a key component in modern technologies such as semiconductors and photovoltaic cells. Critical minerals support the move towards a greater reliance on electrification, renewable energy sources and economic security. The global transition to net zero carbon emissions means there is a growing need for new discoveries of HPQ to supply the silicon production chain. HPQ deposits are identified in a multitude of geological settings, including pegmatites, hydrothermal veins, sedimentary accumulations and quartzite; however, deposits of sufficient volume and quality are rare. Quartz is abundant throughout Australia, but the exploration and discovery of HPQ occurrences are notably under-reported, making assessment of the HPQ potential in Australia extremely difficult. This paper presents a much-needed summary of the state of the HPQ industry, exploration and deposit styles in Australia. KEY POINTS: 1. High-purity quartz (HPQ) is a key material for the manufacture of photovoltaic cells, semiconductors and other high-technology applications. 2. HPQ can be recovered from a variety of different source rocks in a range of geological settings. 3. Currently, the HPQ industry in Australia is under-utilised for high-technology applications, and historical exploration and mining records are under-reported and opaque. 4. This review presents an outline of the characteristics, processing requirements and end uses of HPQ, and a summary of the operations, deposits, exploration targets and known occurrences of HPQ in Australia. <b>Citation:</b> Jennings, A., Senior, A., Guerin, K., Main, P., & Walsh, J. (2024). A review of high-purity quartz for silicon production in Australia. <i>Australian Journal of Earth Sciences</i>, 1–13. https://doi.org/10.1080/08120099.2024.2362296