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  • The preserved successions from the Mesoproterozoic Era (1600 to 1000 Ma) are a relatively understudied part of Australian geological evolution, especially considering that this era has a greater time span than the entire Phanerozoic. These rocks are mostly known in variably-preserved sedimentary basins overlying Paleoproterozoic or Archean cratons or at the margins of these cratons. Some metamorphosed equivalents occur within the orogens between or marginal to these cratons. Both energy and mineral resources are hosted in Australian Mesoproterozoic basins, including the highly-prospective organic rich shale units within the Beetaloo Sub-basin (Northern Territory), which form part of the Beetaloo Petroleum Supersystem. The primary aim for this record is to provide a consolidated state of knowledge of Australian basins or successions similar in age to that of the Mesoproterozoic Beetaloo Petroleum Supersystem. The findings of this report will assist prioritising future work, through improved geological understanding and resource prospectivity. This report presents an overview of 14 Mesoproterozoic-age sedimentary basins or successions and their current level of understanding, including location, basin architecture, stratigraphy and depositional environments, age constraints and mineral and energy resources. Basins or successions included in this record are unmetamorphosed or metamorphosed to very low-grade conditions. Recommendations are made for future work to address the main knowledge gaps identified from this review. While some of these basins have been the focus of recent intense study and data acquisition, the extent of knowledge varies broadly across basins. All basins reviewed in this record would benefit from further geochemical and geochronological analyses, and stratigraphic study to better understand the timing of depositional events and their correlation with nearby basins. Elucidation of the post-depositional history of alteration, migration of fluids and/or hydrocarbons would facilitate future exploration and resource evaluation.

  • <div>The Central Australian Basins 2D Seismic Reprocessing Project is an initiative under Geoscience Australia's "Australia’s Future Energy Resources" (AFER) program, funded by the Australian Government through the "Exploring for the Future" (EFTF) program. The project aims to assess the untapped resource potential of selected underexplored onshore sedimentary basins in terms of natural gas, oil, and groundwater, while also investigating opportunities for geological storage of carbon dioxide and hydrogen. By providing pre-competitive data, the initiative seeks to stimulate investment in mineral, energy, and groundwater exploration.</div><div>&nbsp;</div><div>This project focuses on improving the understanding of the geological evolution and relationships among various Australian basins, ranging from the early Paleozoic Amadeus, Warburton and Adavale basins to the Permian-Triassic Pedirka, Simpson, northern Cooper and southern Galilee basins, and the Jurassic–Cretaceous western Eromanga Basin. To achieve this, modern seismic processing techniques were applied to 33 selected multi-vintage legacy lines with a total length of approximately 2,100 km, enhancing the resolution and image quality of the seismic lines. The dataset includes deep crustal as well as shallow lines from Queensland and South Australia. The data were collected using various acquisition sources such as Vibroseis, Geoflex, and dynamite. Six merged lines were also created to aid in interpretation.</div><div>&nbsp;</div><div>Both stacks and gather data are provided in SEG-Y format, along with navigation data, velocity, and statics. The reprocessing focused on enhancing seismic reflectors and faults, attenuating noise, and optimising frequency content for target depths. Techniques used in the reprocessing include creating a 3D static model, noise attenuation methods, minimum phasing of the Vibroseis data to match dynamite lines, surface-consistent deconvolution, and building a precise velocity model for optimising pre-stack time and depth migration.</div><div><br></div><div><strong>Processed gather data&nbsp;for this survey are also available on request from clientservices@ga.gov.au - Quote eCat# 148931</strong></div>

  • <div>Geoscience Australia’s Exploring for the Future (EFTF) program provides precompetitive information to inform decision-making by government, community and industry on the sustainable development of Australia's mineral, energy and groundwater resources. By gathering, analysing and interpreting new and existing precompetitive geoscience data and knowledge, we are building a national picture of Australia’s geology and resource potential. This leads to a strong economy, resilient society and sustainable environment for the benefit of all Australians. This includes supporting Australia’s transition to net zero emissions, strong, sustainable resources and agriculture sectors, and economic opportunities and social benefits for Australia’s regional and remote communities. The EFTF program, which commenced in 2016, is an eight year, $225m investment by the Australian Government.</div><div>The onshore Canning Basin in Western Australia was the focus of a regional hydrocarbon prospectivity assessment undertaken by the EFTF program dedicated to increasing investment in resource exploration in northern Australia, with the objective being to acquire new data and information about the potential mineral, energy and groundwater resources concealed beneath the surface. As part of this program, significant work has been carried out to deliver pre-competitive data in the region including new seismic acquisition, drilling of a stratigraphic well, and geochemical analysis from historic exploration wells.</div><div>As part of this program, a compilation of the compound-specific isotopic compositions of crude oils from 30 petroleum wells in the Canning Basin have been completed. The samples were analysed in Geoscience Australia’s Isotope and Organic Geochemistry Laboratory and the collated results are released in this report. This report provides additional stable carbon and hydrogen isotopic data to build on the oil-oil correlations previously established by Edwards and Zumberge (2005) and Edwards et al. (2013). This information can be used in future geological programs to determine the origin of the crude oils, and hence increase our understanding of the Larapintine Petroleum Supersystem, as established by Bradshaw (1993) and Bradshaw et al. (1994).</div><div><br></div>

  • <div>Lateral variation in maturity of potential Devonian source rocks in the Adavale Basin has been investigated using nine 1D burial, thermal and petroleum generation history models, constructed using existing open file data. These models provide an estimate of the hydrocarbon generation potential of the basin. Total organic carbon (TOC) content and pyrolysis data indicate that the Log Creek Formation, Bury Limestone and shale units of the Buckabie Formation have the most potential as source rocks. The Log Creek Formation and the Bury Limestone are the most likely targets for unconventional gas exploration.</div><div>The models were constructed using geological information from well completion reports to assign formation tops and stratigraphic ages, and then forward model the evolution of geophysical parameters. The rock parameters, including facies, temperature, organic geochemistry and petrology, were used to investigate source rock quality, maturity and kerogen type. Suitable boundary conditions were assigned for paleo-heat flow, paleo-surface temperature and paleo-water depth. The resulting models were calibrated using bottom hole temperature and measured vitrinite reflectance data.</div><div>The results correspond well with published heat flow predictions, although a few wells show possible localised heat effects that differ from the basin average. The models indicate that three major burial events contribute to the maturation of the Devonian source rocks, the first occurring from the Late Devonian to early Carboniferous during maximum deposition of the Adavale Basin, the second in the Late Triassic during maximum deposition of the Galilee Basin, and the third in the Late Cretaceous during maximum deposition of the Eromanga Basin. Generation in the southeastern area appears to have not been effected by the second and third burial events, with hydrocarbon generation only modelled during the Late Devonian to early Carboniferous event. This suggests that Galilee Basin deposition was not significant or was absent in this area. Any potential hydrocarbon accumulations could be trapped in Devonian sandstone, limestone and mudstone units, as well as overlying younger sediments of the Mesozoic Eromanga Basin. Migration of the expelled hydrocarbons may be restricted by overlying regional seals, such as the Wallumbilla Formation of the Eromanga Basin. Unconventional hydrocarbons are a likely target for exploration in the Adavale Basin, with potential for tight or shale gas from the Log Creek Formation and Bury Limestone in favourable areas.</div>

  • <div>The Adavale Basin is located approximately 850 km west-northwest of Brisbane and southwest of Longreach in south-central Queensland. The basin system covers approximately 100,000 km2 and represents an Early to Late Devonian (Pragian to Famennian) depositional episode, which was terminated in the Famennian by widespread contractional deformation, regional uplift and erosion. </div><div>Burial and thermal history models were constructed for nine wells using existing open file data to assess the lateral variation in maturity and temperature for potential source rocks in the Adavale Basin, and to provide an estimate of the hydrocarbon generation potential in the region.</div>

  • <div> A key issue for explorers in Australia is the abundant sedimentary and regolith cover obscuring access to underlying potentially prospective rocks. &nbsp;Multilayered chronostratigraphic interpretation of regional broad line-spaced (~20&nbsp;km) airborne electromagnetic (AEM) conductivity sections have led to breakthroughs in Australia’s near-surface geoscience. &nbsp;A dedicated/systematic workflow has been developed to characterise the thickness of cover and the depth to basement rocks, by delineating contact geometries, and by capturing stratigraphic units, their ages and relationships. &nbsp;Results provide a fundamental geological framework, currently covering 27% of the Australian continent, or approximately 2,085,000&nbsp;km2. &nbsp;Delivery as precompetitive data in various non-proprietary formats and on various platforms ensures that these interpretations represent an enduring and meaningful contribution to academia, government and industry.&nbsp;The outputs support resource exploration, hazard mapping, environmental management, and uncertainty attribution.&nbsp;This work encourages exploration investment, can reduce exploration risks and costs, helps expand search area whilst aiding target identification, and allows users to make well-informed decisions. Presented herein are some key findings from interpretations in potentially prospective, yet in some cases, underexplored regions from around Australia.&nbsp;</div> This abstract was submitted & presented to the 8th International Airborne Electromagnetics Workshop (AEM2023) (https://www.aseg.org.au/news/aem-2023)

  • Exploring for the Future (EFTF) is an Australian Government program led by Geoscience Australia (GA), in partnership with state and Northern Territory governments. The EFTF program (2016-2024) aims to drive industry investment in resource exploration in frontier regions of onshore Australia by providing new precompetitive data and information about their energy, mineral and groundwater resource potential. Under the EFTF program, the Basin Inventory Project undertook a study of petroleum prospectivity of the onshore Eromanga Basin in Queensland and South Australia. Yongala 1 well in Queensland was selected based on the occurrence of gas and oil shows reported in the well completion report. Sampling of cuttings and cores was done at Geoscience Australia's Petroleum Data Repository in Canberra. Geoscience Australia commissioned a fluid inclusion stratigraphy (FIS) study on the downhole samples. Here, volatile components ostensibly trapped with fluid inclusions are released and analysed revealing the level of exposure of the well section to migrating fluids. Integration of thin section (TS) preparations reveal the extent of gas and fluid trapping within fluid inclusions while microthemometry (MT) gives an estimation of fluid inclusion trapping temperature. For Yongala 1, FIS analysis was performed on 418 cuttings and 52 cores between 15.2 metres and 3104.5 metres base depth, together with 22 samples prepared for TS and 3 samples for MT. To support this study, lithostratigraphic tops were compiled by Geoscience Australia. The results of the study are found in the accompanying documents.

  • <div>The interpretation of AusAEM airborne electromagnetic (AEM) survey conductivity sections in the Canning Basin region delineates the geo-electrical features that correspond to major chronostratigraphic boundaries, and captures detailed stratigraphic information associated with these boundaries. This interpretation forms part of an assessment of the underground hydrogen storage potential of salt features in the Canning Basin region based on integration and interpretation of AEM and other geological and geophysical datasets. A main aim of this work was to interpret the AEM to develop a regional understanding of the near-surface stratigraphy and structural geology. This regional geological framework was complimented by the identification and assessment of possible near-surface salt-related structures, as underground salt bodies have been identified as potential underground hydrogen storage sites. This study interpreted over 20,000 line kilometres of 20&nbsp;km nominally line-spaced AusAEM conductivity sections, covering an area approximately 450,000 km2 to a depth of approximately 500&nbsp;m in northwest Western Australia. These conductivity sections were integrated and interpreted with other geological and geophysical datasets, such as boreholes, potential fields, surface and basement geology maps, and seismic interpretations. This interpretation produced approximately 110,000 depth estimate points or 4,000 3D line segments, each attributed with high-quality geometric, stratigraphic, and ancillary data. The depth estimate points are formatted for Geoscience Australia’s Estimates of Geological and Geophysical Surfaces database, the national repository for formatted depth estimate points. Despite these interpretations being collected to support exploration of salt features for hydrogen storage, they are also intended for use in a wide range of other disciplines, such as mineral, energy and groundwater resource exploration, environmental management, subsurface mapping, tectonic evolution studies, and cover thickness, prospectivity, and economic modelling. Therefore, these interpretations will benefit government, industry and academia interested in the geology of the Canning Basin region.</div>

  • <div>In Australia, wide-spread sedimentary basin and regolith cover presents a key challenge to explorers, environmental managers and decision-makers, as it obscures underlying rocks of interest. To address this, a national coverage of airborne electromagnetics (AEM) with a 20&nbsp;km line-spacing is being acquired. This survey is acquired as part of the Exploring for the Future program and in collaboration with state and territory geological surveys. This survey presents an opportunity for regional geological interpretations on the modelled AEM data, helping constrain the characteristics of the near-surface geology beneath the abundant cover, to a depth of up to ~500&nbsp;m.</div><div> The AEM conductivity sections were used to delineate key chronostratigraphic boundaries, e.g. the bases of geological eras, and provide a first-pass interpretation of the subsurface geology. The interpretation was conducted with a high level of data integration with boreholes, potential fields geophysics, seismic, surface geology maps and solid geology maps. This approach led to the construction of well-informed geological interpretations and provided a platform for ongoing quality assurance and quality control of the interpretations and supporting datasets. These interpretations are delivered across various platforms in multidimensional non-proprietary open formats, and have been formatted for direct upload to Geoscience Australia’s (GA) Estimates of Geological and Geophysical Surfaces (EGGS) database, the national repository of multidisciplinary subsurface depth estimates.</div><div> These interpretations have resulted in significant advancements in our understanding of Australia’s near-surface geoscience, by revealing valuable information about the thickness and composition of the extensive cover, as well as the composition, structure and distribution of underlying rocks. Current interpretation coverage is ~110,000 line kilometres of AEM conductivity sections, or an area &gt;2,000,000&nbsp;km2, similar to the area of Greenland or Saudi Arabia. This ongoing work has led to the production of almost 600,000 depth estimate points, each attributed with interpretation-specific metadata. Three-dimensional line work and over 300,000 points are currently available for visualisation, integration and download through the GA Portal, or for download through GA’s eCat electronic catalogue. </div><div> These interpretations demonstrate the benefits of acquiring broadly-spaced AEM surveys. Interpretations derived from these surveys are important in supporting regional environmental management, resource exploration, hazard mapping, and stratigraphic unit certainty quantification. Delivered as precompetitive data, these interpretations provide users in academia, government and industry with a multidisciplinary tool for a wide range of investigations, and as a basis for further geoscientific studies.</div> Abstract submitted and presented at 2023 Australian Earth Science Convention (AESC), Perth WA (https://2023.aegc.com.au/)

  • Exploring for the Future (EFTF) is an Australian Government program led by Geoscience Australia (GA), in partnership with state and Northern Territory governments. The EFTF program (2016-2024) aims to drive industry investment in resource exploration in frontier regions of onshore Australia by providing new precompetitive data and information about their energy, mineral and groundwater resource potential. Under the EFTF program, the Basin Inventory Project undertook a study of petroleum prospectivity of the onshore Eromanga Basin in Queensland and South Australia. Gilmore 1 well in Queensland was selected based on the occurrence of gas and oil shows reported in the well completion report. Sampling of cuttings and cores was done at Geoscience Australia's Petroleum Data Repository in Canberra. Geoscience Australia commissioned a fluid inclusion stratigraphy (FIS) study on the downhole samples. Here, volatile components ostensibly trapped with fluid inclusions are released and analysed revealing the level of exposure of the well section to migrating fluids. Integration of thin section (TS) preparations reveal the extent of gas and fluid trapping within fluid inclusions while microthemometry (MT) gives an estimation of fluid inclusion trapping temperature. For Gilmore 1, FIS analysis was performed on 498 cuttings and 71 cores between 9.1 metres and 4346 metres base depth, together with 22 samples prepared for TS and 4 samples for MT. To support this study, lithostratigraphic tops were compiled by Geoscience Australia. The results of the study are found in the accompanying documents.