Geoscience Australia’s Exploring for the Future 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 Exploring for the Future program, which commenced in 2016, is an eight year, $225m investment by the Australian Government. The name ‘Birrindudu Basin’ was first introduced by Blake et al. (1975) and Sweet (1977) for a succession of clastic sedimentary rocks and carbonates, originally considered to be Paleoproterozoic to Neoproterozoic in age, and overlain by the Neoproterozoic Victoria Basin (Dunster et al., 2000), formerly known as the Victoria River Basin (see Sweet, 1977).

One of the aims of the Exploring for the Future program is to promote the discovery of new mineral deposits in undercover frontiers. Iron oxide–copper–gold mineral systems are a desirable candidate for undercover exploration, because of their potential to generate large deposits with extensive alteration footprints. This mineral potential assessment uses the mineral systems concept: developing mappable proxies of required theoretical criteria, combined to demonstrate where conditions favourable for mineral deposit formation are spatially coincident. This assessment uses a 2D geographical information system workflow to map the favourability of the key mineral system components. Two outputs were created: a comprehensive assessment, using all available spatial data; and a coverage assessment, which is constrained to data that have no reliance on outcrop. The results of these assessment outputs were validated with spatial statistics, demonstrating how the assessment can predict the presence of known ore deposits. Both assessment outputs present new areas of interest with prospectivity in under-explored regions of undercover northern Australia. The intended aims are already being realised, as this tool has aided area selection for pre-competitive stratigraphic drilling as part of the MinEx CRC National Drilling Initiative. <b>Citation:</b> Murr, J., Skirrow, R.G., Schofield, A., Goodwin, J., Coghlan, R., Highet, L., Doublier, M.P., Duan, J. and Czarnota, K., 2020. Tennant Creek – Mount Isa IOCG mineral potential assessment. 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.

As part of the Great Artesian Basin (GAB) Project a pilot study was conducted in the northern Surat Basin, Queensland, to test the ability of existing and new geoscientific data and technologies to further improve our understanding of hydrogeological systems within the GAB, in order to support responsible management of basin water resources. This report presents selected examples from the preliminary interpretation of modelled airborne electromagnetic (AEM) data acquired as part of this pilot study. The examples are selected to highlight key observations from the AEM with potential relevance to groundwater recharge and connectivity. Previous investigations in the northern Surat Basin have suggested that diffuse groundwater recharge rates are generally low (in the order of only a few millimetres per year) across large areas of the GAB intake beds—outcropping geological units which represent a pathway for rainfall to enter the aquifers—and that, within key aquifer units, recharge rates and volumes can be heterogeneous. Spatial variability in AEM conductivity responses is identified across different parts of the northern Surat Basin, including within the key Hutton Sandstone aquifer. Consistent with findings from other studies, this variability is interpreted as potential lithological heterogeneity, which may contribute to reduced volumes of groundwater entering the deeper aquifer. The influence of geological structure on aquifer geometry is also examined. Larger structural zones are seen to influence both pre- and post-depositional architecture, including the presence, thickness and dip of hydrogeological units (or parts thereof). Folds and faults within the Surat Basin sequences are, in places, seen as potential groundwater divides which may contribute to compartmentalisation of aquifers. Discrete faults have the potential to influence inter-aquifer connectivity. The examples presented here demonstrate the utility of AEM models, in conjunction with other appropriate geophysical and geological data, for characterising potential recharge areas and pathways within the main GAB aquifer units, by helping to better define aquifer geometry, lithological heterogeneity and possible structural controls. Such assessments have the potential to further improve our understanding of groundwater recharge and flow path variability at local to regional scales. Acquisition of broader AEM data coverage across groundwater recharge areas, along with complementary geophysical, geological and hydrogeological data, would further assist in quantifying recharge variability, facilitating revised water balance estimates for the basin and thereby supporting GAB water resource management and policy decision-making.

Fresh groundwater stored in Australian coastal aquifers is an important resource for humans and the natural environment. Many Australian coastal aquifers are vulnerable to seawater intrusion (SWI)—the landward encroachment of sea water into coastal aquifers—which can significantly degrade water quality and reduce freshwater availability. The increasing demands for fresh water in coastal areas and the anticipated impacts of climate change (such as sea-level rise and variations in rainfall recharge) may result in increases in the incidence and severity of SWI. Comprehensive investigations of SWI are relatively uncommon and the extent of monitoring and investigations specific to SWI are highly variable across the nation. In response to the threat posed by SWI, Geoscience Australia and the National Centre for Groundwater Research and Training, in collaboration with state and territory water agencies, undertook a national-scale assessment of the vulnerability of coastal aquifers to SWI. This assessment identified the coastal groundwater resources that are most vulnerable to SWI, including future consequences of over-extraction, sea-level rise, and recharge–discharge variations associated with climate change. The study focused on assessing the vulnerability of coastal aquifers to the landward migration of the freshwater–saltwater interface, rather than surface waterbodies.

This report presents groundwater levels results from the Upper Burdekin Groundwater Project in North Queensland, 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 Upper Burdekin Groundwater Project is a collaborative study between Geoscience Australia and the Queensland Government. It focuses on basalt groundwater resources in two geographically separate areas: the Nulla Basalt Province (NBP) in the south and the McBride Basalt Province (MBP) in the north. This report describes a data release of water levels measured in monitoring bores in both provinces by Geoscience Australia during the EFTF project. It 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 dataloggers 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 (i) 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 B, and (ii) Data files in CSV file format reporting the final water levels used to generate the hydrographs in Appendix B. This data release report does not include hydrograph interpretation, which is undertaken in detail in: Cook, S. B. & Ransley, T. R., 2020. Exploring for the Future—Groundwater level interpretations for the McBride and Nulla basalt provinces: Upper Burdekin region, North Queensland. Geoscience Australia, Canberra, https://pid.geoscience.gov.au/dataset/ga/135439.

This report presents key results of groundwater barometric response function development and interpretation from the Upper Burdekin Groundwater Project in North Queensland, 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 Upper Burdekin Groundwater Project is a collaborative study between Geoscience Australia and the Queensland Government. It focuses on basalt groundwater resources in two geographically separate areas: the Nulla Basalt Province (NBP) in the south and the McBride Basalt Province (MBP) in the north. The NBP and MBP basalt aquifers are heterogeneous, fractured, vesicular systems. This report assesses how water levels in monitoring bores in the NBP and MBP respond to barometric pressure changes to evaluate the degree of formation confinement. The main process used to evaluate water level response to barometric pressure in this study is based on barometric efficiency (BE). The BE of a formation is calculated by dividing the change in monitoring bore water level by the causative barometric pressure change. Both parameters are expressed in the same units, so BE will typically be some fraction between zero and one. BE is not necessarily constant over time; the way BE changes following a theoretical step change in barometric pressure can be described using a barometric response function (BRF). BRFs were calculated in the time domain and plotted as BE against time lag for interpretation. The BRF shape was used to assess the degree of formation confinement. Although there is some uncertainty due to monitoring bore construction issues (including long effective screens) and potentially air or gas trapped in the saturated zone, all BRFs in the current project are interpreted to indicate unconfined conditions. This finding is supported by the identification of recharge at many monitoring bores through hydrograph analysis in other EFTF project components. We conclude that formations are likely to be unconfined at many project monitoring bores assessed in this study.

The Geological Survey of South Australia (GSSA) designed the Gawler Craton Airborne Survey (GCAS) to provide high resolution magnetic, gamma-ray and elevation data covering the northern portion of the Gawler Craton. In total, 1.66 million line km were planned over an area of 295,000 km2 , covering approximately 30% of the state of South Australia. The survey design of 200 m spaced lines at a ground clearance of 60 m can be compared with the design of existing regional surveys which generally employed 400 m line spacing and a ground clearance of 80 m. The new survey design results in ~2 x the data coverage and ~25% closer to the ground when compared to previous standards for regional surveys in South Australia. Due to the enormous scale of the survey, the data were acquired using four contractors who employed ten systems to fly the sixteen blocks. To standardise the data from the multitude of systems, Geoscience Australia (GA) employed a comprehensive set of technical specifications. As part of these specifications the contractors were required to fly each of the ten systems over a series of test lines termed the “Whyalla Test Lines” (Whyalla). The final GCAS data provide truly impressive high resolution regional scale products. These will allow more detailed geological interpretation of the prospective Gawler Craton. Survey blocks available for download include: Tallaringa North, block 1A Tallaringa South, block 1B Coober Pedy West, block 8A Billa Kalina, block 8B Childara, block 9A Lake Eyre, block 10 The following grids are available in this download: • Laser-derived digital elevation model grids (m). Height relative to the Australian Height Datum. • Radar-derived digital elevation model grids (m). Height relative to the Australian Height Datum. • Total magnetic intensity grid (nT). • Total magnetic intensity grid with variable reduction to the pole applied (nT). • Total magnetic intensity grid with variable reduction to the pole and first vertical derivative applied (nT/m). • Dose rate concentration grid (nGy/hr). • Potassium concentration grid (%). • Thorium concentration grid (ppm). • Uranium concentration grid (ppm). • NASVD processed dose rate concentration grid (nGy/hr). • NASVD processed potassium concentration grid (%). • NASVD processed thorium concentration grid (ppm). • NASVD processed uranium concentration grid (ppm). The following point located data are available in this download: • Elevation. Height relative to the Australian Height Datum. Datum: GDA94 • Total Magnetic Intensity. Datum: GDA94 • Radiometrics. Datum: GDA94

<div>The groundwater and surface water systems associated with the Upper Darling River Floodplain (UDF) in arid northwest New South Wales form part of the Murray-Darling Basin drainage system, which hosts 40% of Australia’s agricultural production. Increasing water use demands and a changing regional climate are affecting hydrological systems, and consequently impacting the quality and quantity of water availability to communities, industries and the environment.</div><div>As part of the Australian Government’s Exploring for the Future program, the UDF project is working in collaboration with State partners to collect and integrate new data and information with existing hydrogeological knowledge. The goal is to provide analyses and products that assist water managers to increase water security in the region, with a focus on groundwater resources. </div><div>As part of this project we are assessing the occurrence of, and geological controls on, potable water resources within the Darling Alluvium (DA), which comprises unconsolidated sediments (<140 m thick) associated with the modern and paleo-Darling River. The DA’s relationship to the underlying Eromanga, Surat (Great Artesian Basin) and Murray basins is also important, particularly in the context of potential groundwater sources or sinks, and connection between low and high quality groundwater resources. At least one major fault system is known to influence groundwater flow paths and control groundwater-surface water interaction.</div><div>Data collection across the project area has commenced, with an airborne electromagnetic (AEM) survey already complete, and new geophysical, hydrochemical and hydrodynamic data being acquired. Preliminary interpretation of the new AEM data in conjunction with existing geological and hydrogeological information has already revealed the major paths and geometries of the paleo-Darling River, given important insights into potential fault controls on groundwater flow paths, and shown variation in the thickness, distribution and character of the DA, which has direct implications for groundwater–surface water connectivity.</div><div><br></div>

Presentation to Australian Research Council (ARC) Training Centre for Data Analytics in Resources and Environment (DARE) Symposium (17 February 2023, University of Sydney) demonstrating use of uncertainty in hydrogeophysical applications as part of the Upper Darling River Floodplain EFTF project.

This context report is for the Upper Darling River Floodplain module, which represents the easternmost ‘arm’ of the Exploring for the Future Darling-Curnamona-Delamerian project area within New South Wales. The document provides a summarised state of knowledge regarding the geography, geology, hydrology, hydrogeology and water management of the Upper Darling region. It provides baseline information relevant to understanding the regional context of water resources, with relevance to forward planning and prioritisation of further investigations. As such, this report largely represents a collation of existing information (literature review) for the Upper Darling region, with limited new information (e.g., airborne electromagnetic survey results, preliminary review of existing bore data) being presented.