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  • The Layered Geology of Australia web map service is a seamless national coverage of Australia’s surface and subsurface geology. Geology concealed under younger cover units are mapped by effectively removing the overlying stratigraphy (Liu et al., 2015). This dataset is a layered product and comprises five chronostratigraphic time slices: Cenozoic, Mesozoic, Paleozoic, Neoproterozoic, and Pre-Neoproterozoic. As an example, the Mesozoic time slice (or layer) shows Mesozoic age geology that would be present if all Cenozoic units were removed. The Pre-Neoproterozoic time slice shows what would be visible if all Neoproterozoic, Paleozoic, Mesozoic, and Cenozoic units were removed. The Cenozoic time slice layer for the national dataset was extracted from Raymond et al., 2012. Surface Geology of Australia, 1:1 000 000 scale, 2012 edition. Geoscience Australia, Canberra.

  • The Exploring for the Future Program (EFTF) is a $100.5 million four year, federally funded initiative to better characterise the mineral, energy and groundwater potential of northern Australia. A key focus area of the initiative is the South Nicholson region, situated across the Northern Territory and Queensland border. The South Nicholson region is located between two highly prospective provinces, the greater McArthur Basin in the Northern Territory, the Lawn Hill Platform and the Mount Isa Province in Queensland–Northern Territory, which both have demonstrated hydrocarbon and base metal resources. In contrast, the South Nicholson region is not well understood geologically, is mostly undercover with limited well data, and prior to EFTF contained limited seismic coverage. Re–Os analyses in this study were undertaken to complement seismic data, U–Pb geochronology and geochemistry data to better understand the geological evolution and resource potential of the South Nicholson region. Five organic carbon bearing sedimentary samples from drillholes BMR Ranken 1, NTGS00/1, DDH 83/1 and DDH 83/4 located across the South Nicholson region were analysed for whole rock Re–Os. The aim of the analyses was to better constrain the depositional age of basin units in the region, and to potentially provide insights into the timing of post-depositional processes such as fluid events and hydrocarbon generation and/or migration. Samples belong to the Mesoproterozoic South Nicholson Group, Paleoproterozoic Fickling and McNamara groups, and the Neoproterozoic to Devonian Georgina Basin. Samples were analysed at the University of Alberta, Canada.

  • Australia’s longest onshore seismic line (18GA-KB1) across the southern Canning Basin informs resource evaluation of the frontier Kidson Sub-basin and Waukarlycarly Embayment. The Kidson Sub-basin covers 91 000 km2 and has a sag basin architecture. Preliminary interpretation of the seismic data indicates that the sedimentary basin is approximately 6 km deep, and includes a conformable package of Ordovician–Devonian siliciclastic, carbonate and evaporite facies of exploration interest. Located in the western end of the seismic line, the newly drilled deep stratigraphic well Waukarlycarly 1 penetrated 2680.53 m from the rotary table of Cenozoic and Paleozoic strata in the Waukarlycarly Embayment. This abstract reviews the Larapintine petroleum systems and discusses their possible extension into this frontier region. Recently published geochemical analyses of source rocks, oils and gases produced from exploration wells are coupled with new data on fluid inclusion gases (FIGs) from sedimentary sections in untested petroleum wells to provide correlation to hydrocarbons migrating within data-poor areas of the basin. Amplitude anomalies on the seismic line suggest the possibility of gas in the Waukarlycarly Embayment. Integration of the seismic derivative data with the results of the FIG analyses have determined the widespread generation of gas from Paleozoic sources within the Canning Basin, extending the spatial extent of the three petroleum systems described from the Lennard Shelf, Fitzroy Trough and Broome Platform. <b>Citation:</b> Carr, L.K., Edwards, D.S., Southby, C. Henson, P., Haines, P., Normore, L., Zhan, A., Brooks, D., MacFarlane, S., Boreham, C.J., Grosjean, E., Mory A.J., Wang, L. and Gunning, M-E., 2020. Kidson Sub-basin seismic survey and Waukarlycarly 1 stratigraphic well: an acquisition program for evaluating Canning Basin petroleum systems. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

  • Geoscience Australia, in collaboration with state governments, will be carrying out airborne electromagnetic (AEM) surveys in western South Australia, southern NT and eastern WA during 2022. This scientific research is being carried out to obtain data that will enhance understanding of geology and natural resources of the region. This information will support future resource management decision-making. This survey has been expanded into Western Australia with funding from the Geological Survey of Western Australia, combined with valuable in-kind support from the South Australian and Northern Territory geological surveys. <p>

  • <p>Australia has a significant number of surface sediment geochemical surveys that have been undertaken by industry and government during the past 50 years. These surveys represent a vast investment, but up to now have been used in isolation from one another. The key to maximising the full potential of these data and the information they provide for mineral exploration, environmental management and agricultural purposes is using all surveys together, seamlessly. These geochemical surveys have not only sampled various landscape elements but have used multiple analytical techniques, instrumentation and laboratories. The geochemical data from these surveys need to be levelled to eliminate, as much as possible, non-geological variation. Using a variety of methodologies, including reanalysis of both international standards and small subsets of samples from previous surveys, we have created a seamless surface geochemical map for northern Australia, from nine surveys with 15605 samples. We tested our approach using two surveys from the southern Thomson Orogen, which removed interlaboratory and other analytical variation. Creation of the new combined and levelled northern Australian dataset paves the way for the application of statistical techniques, such as principal component analysis and machine learning, which maximise the value of these legacy data holdings. The methodology documented here can be applied to additional geochemical datasets that become available. <p><b>Citation:</b> Main, P. T. and Champion, D. C., 2020. Geochemistry of the North Australian Craton: piecing it together. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

  • This Record presents twelve new zircon U-Pb geochronological results from the South Nicholson region, conducted on Geoscience Australia’s Sensitive High Resolution Ion Micro Probe (SHRIMP), as part of the Commonwealth Government’s Exploring for the Future (EFTF) program, an initiative to better understand the mineral, energy and groundwater potential of northern Australia. These data will facilitate greater understanding of the geological evolution of the South Nicholson region, a vast and underexplored region extending across north-eastern Northern Territory and far north-western Queensland. Samples were collected from across the South Nicholson region including MOUNT DRUMMOND, CALVERT HILLS, BRUNETTE DOWNS (NT), LAWN HILL and CAMOOWEAL (QLD) 250K mapsheets. Four samples are from outcrop and eight samples from six stratigraphic and exploration drillholes. Samples were collected from the Paleoproterozoic Murphy Province and from overlying successions of the Paleoproterozoic Benmara Group and the Mesoproterozoic South Nicholson Group. Several samples from drillholes, have stratigraphic affinities that are uncertain and speculative.

  • This Tasmania Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Late Carboniferous to Late Triassic Tasmania Basin covers approximately 30,000 square kilometres of onshore Tasmania. The basin contains up to 1500 m of mostly flat-lying sedimentary rocks, and these are divided into two distinct lithostratigraphic units, the Lower and the Upper Parmeener Supergroup. The Lower Parmeener Supergroup comprises Late Carboniferous to Permian rocks that mainly formed in marine environments. The most common rock types in this unit are mudstone, siltstone and sandstone, with less common limestone, conglomerate, coal, oil shale and tillite. The Upper Parmeener Supergroup consists predominantly of non-marine rocks, typically formed in fluvial and lacustrine environments. Common rock types include sandstone, siltstone, mudstone and minor basalt layers. Post-deposition the rocks of the Parmeener Supergroup experienced several major geological events, including the widespread intrusion of tholeiitic dolerite magma during the Middle Jurassic.

  • This report presents groundwater levels results from the Southern Stuart Corridor project conducted as part of Exploring for the Future (EFTF), an eight year, $225 million Australian Government-funded geoscience data and information acquisition program focused on better understanding the potential mineral, energy and groundwater resources across Australia. The Southern Stuart Corridor project is a collaborative study between Geoscience Australia the Northern Territory Department of Environment and Natural Resources (DENR) and Power and Water Corporation (PWC) which incorporates study areas between Alice Springs and Tennant Creek in south-central NT. Groundwater level data were collected from newly drilled bores in the Western Davenport and Alice Springs areas. This report records the release of groundwater level data gathered by Geoscience Australia and DENR from monitoring bores in the Southern Stuart Corridor project area during the EFTF project. The full report includes: • A full description of how water levels in metres relative to Australian Height Datum (m AHD; where zero m AHD is an approximation of mean sea level) were calculated from manual dips and electronic data loggers for this project. • A series of tables in Appendix A containing sufficient information for each bore and datalogger file to reproduce the water levels reported in Appendix B and Appendix C. • A series of hydrographs in Appendix B showing how water levels (in m AHD) interpreted from manual dips and datalogger files varied during the EFTF project. • A series of electronic files in Appendix C that include - Data files from dataloggers in CSV file format that can be used with the information contained in this data release to regenerate the water levels shown on hydrographs in Appendix A. - Data files in CSV file format reporting the final water levels used to generate the hydrographs in Appendix B.

  • Improvements in discovery and management of minerals, energy and groundwater resources are spurred along by advancements in surface and subsurface imaging of the Earth. Over the last half decade Australia has led the world in the collection of regionally extensive airborne electromagnetic (AEM) data coverage, which provides new constraints on subsurface conductivity structure. Inferring geology and hydrology from conductivity is non-trivial as the conductivity response of earth materials is non-unique, but careful calibration and interpretation does provide significant insights into the subsurface. To date utility of this new data is limited by its spatial extent. The AusAEM survey provides conductivity constraints every 12.5 m along flight lines with no constraints across vast areas between flight lines spaced 20 km apart. Here we provide a means to infer the conductivity between flight lines as an interim measure before infill surveys can be undertaken. We use a gradient boosted tree machine learning algorithm to discover relationships between AEM conductivity models across northern Australia and other national data coverages for three depth ranges: 0–0.5 m, 9–11 m and 22–27 m. The predictive power of our models decreases with depth but they are nevertheless consistent with our knowledge of geological, landscape evolution and climatic processes and an improvement on standard interpolation methods such as kriging. Our models provide a novel complementary methodology to gridding/interpolating from AEM conductivity alone for use by the mining, energy and natural resource management sectors. <b>Citation: </b>Wilford J., Ley-Cooper Y., Basak S., & Czarnota K., 2022. High resolution conductivity mapping using regional AEM survey and machine learning. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146380.

  • Groundwater is an essential part of Darwin’s water supply mix, and is sourced from Howard East Borefield (HEB) and McMinns Borefield in the Koolpinyah Dolostone Aquifer (KDA), east of Darwin. Previous work suggested that electrical conductivity anomalies observed in airborne electromagnetic (AEM) data within 8 km of HEB may be caused by saline groundwater within the KDA that is separated from HEB by geological features that effectively compartmentalise the aquifer. Nevertheless, concerns grew that increased groundwater use may result in migration of saline groundwater towards HEB, which could compromise the groundwater resource. We collected hydrochemistry, including isotopes, time-series groundwater salinity and AEM data to better understand the complexities of the KDA. These data are presented here, along with a hydrodynamic analysis undertaken by the Northern Territory Department of Environment and Natural Resources, which shows that drawdown is occurring more rapidly from the NE of HEB and that dykes ~8 km NE of HEB act as barriers to groundwater flow. We show that groundwater sampled on the NE side of these dykes has a seawater composition. We use new AEM data to map the elevation of the top of unweathered dyke material and to characterise AEM conductors proximal to HEB. Our mapping reveals that the top of the unweathered portion of these dykes is commonly below sea level. We also show that AEM conductors proximal to HEB are more likely mineralised clays than saline groundwater within the aquifer. Drilling is required to confirm these results. Our findings contribute to building a robust conceptual understanding of the KDA and will inform future modelling of the groundwater system. <b>Citation:</b> Haiblen, A.M., Symington, N.J., Woltmann, M.J., Ray, A., Gow, L.J., Leplastrier, A. and McGrath, E.S.B., 2020. A multifaceted approach to investigating hydrogeological complexities in the Koolpinyah Dolostone Aquifer, Howard East, Northern Territory. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.