<div>The Australian Government's Trusted Environmental and Geological Information program is a collaboration between Geoscience Australia and CSIRO. Part of this program includes baseline geological and environmental assessments. </div><div> Hydrogeological information has been collated for the Adavale, Cooper, Galilee and north Bowen basins and overlying basins, including the Eromanga and Lake Eyre basins. This information will provide a regionally-consistent baseline dataset that will be used to develop groundwater conceptualisation models.</div><div> Publicly-available data within these basin regions have been compiled from over 30&nbsp;000 boreholes, 120 stream gauges, and 1100 rainfall stations, resulting in revised hydrostratigraphic frameworks. From the published literature, 14 major hydrostratigraphic units are recognised within the basin regions. For each of these major hydrostratigraphic units, we determined the salinity, Darcian yield, specific yield/storativity, groundwater reserve volume for unallocated groundwater, groundwater levels/hydrological pressure, likelihood of inter-aquifer connectivity, rainfall, connectivity between surface water and groundwater, and water-use volume statistics, where relevant, for each basin, hydrogeological province and aquifer. We then adopted a play-based approach to develop holistic hydrostratigraphic conceptualisations of the basin regions. </div><div> Within the Adavale Basin we have defined a new hydrogeological province including two new aquifers defined as the moderate salinity and moderately overpressured Buckabie-Etonvale Aquifer, and the hypersaline and hyper-overpressured Lissoy-Log Creek-Eastwood Aquifer. Similarities between the upper Buckabie-Etonvale Aquifer of the Adavale Basin and lowermost Joe Joe Group of the Galilee Basin suggests connectivity between the upper Adavale and lower Galilee basins. Hydraulic pressures (up to 1500 m of excess freshwater head) calculated for the Lissoy–Log Creek–Eastwood Aquifer indicate that if the aquifer was to be breached, there is potential localised risk to overlying aquifers and surface environments, including infrastructure.</div><div><br></div><div><strong>Author Biography:</strong></div><div>Dr. Chris Gouramanis is a hydrogeologist working in the Trusted Environmental and Geological Information program, in the Minerals, Energy and Groundwater Division of Geoscience Australia. Chris was awarded his PhD from The Australian National University in 2009 and has held several water and environmental policy positions within the Australian Government. He worked for 10 years as an academic at the Earth Observatory of Singapore and the Geography Department at the National University of Singapore. He is also Australia’s National Focal Point to the Scientific and Technical Review Panel of the Ramsar Convention on Wetlands.</div><div><br></div>This Abstract was submitted/presented to the 2022 Australasian Groundwater Conference 21-23 November (https://agc2022.com.au/)

A large proportion of Australia’s onshore sedimentary basins remain exploration frontiers. Industry interest in these basins has recently increased due to the global and domestic energy demand, and the growth in unconventional hydrocarbon exploration. In 2016 and 2018, Geoscience Australia released an assessment of several central Australian basins that summarised the current status of geoscientific knowledge and petroleum exploration, and the key questions, for each basin. This publication provides a comprehensive assessment of the geology, petroleum systems, exploration status and data coverage for the Adavale Basin.

<div>Lateral variation in maturity of potential Devonian source rocks in the Adavale Basin have 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>&nbsp;</div><div>The models were constructed used geological information from well completion reports to assign formation tops and stratigraphic ages to then forward-model the evolution of geophysical parameters. The rock parameters, including facies, temperature, organic geochemistry/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>&nbsp;</div><div>The results correspond relatively well with published heat flow predictions, however a few wells show possible localised heat effects that differ from the overall basin average. The models indicate full maturation of the Devonian source rocks with generation occurring during the Carboniferous and again during the Late Cretaceous. Any potential accumulations may be trapped in Devonian sandstone, limestone and mudstone units, as well as overlying younger sediments of the Mesozoic Eromanga Basin. Accumulations could be trapped by localised deposits of the Cooladdi Dolomite and other marine, terrestrial clastic and evaporite units around the 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 the Adavale Basin with potential either for tight or shale gas in favourable areas from the Log Creek Formation and Bury Limestone.</div> This Abstract was submitted/presented to the 2023 Australian Exploration Geoscience Conference 13-18 Mar (https://2023.aegc.com.au/)

All commercially produced hydrogen worldwide is presently stored in salt caverns. In eastern Australia, the only known thick salt accumulations are found in the Boree Salt of the Adavale Basin in central Queensland. Although the number of wells penetrating the basin is limited, salt intervals up to 555 m thick have been encountered. The Boree Salt consists predominantly of halite and is considered to be suitable for hydrogen storage. Using well data and historical 2D seismic interpretations, we have developed a 3D model of the Adavale Basin, particularly focussing on the thicker sections of the Boree Salt. Most of the salt appears to be present at depths greater than 2000 m, but shallower sections are found in the main salt body adjacent to the Warrego Fault and to the south at the Dartmouth Dome. The preliminary 3D model developed for this study has identified three main salt bodies that may be suitable for salt cavern construction and hydrogen storage. These are the only known large salt bodies in eastern Australia and therefore represent potentially strategic assets for underground hydrogen storage. There are still many unknowns, with further work and data acquisition required to fully assess the suitability of these salt bodies for hydrogen storage. Recommendations for future work are provided. <b>Citation:</b> Paterson R., Feitz A. J., Wang L., Rees S. & Keetley J., 2022. From A preliminary 3D model of the Boree Salt in the Adavale Basin, Queensland. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146935

<div>As part of the Data Driven Discoveries program, Geoscience Australia and the Geological Survey of Queensland collaborated to re-examine legacy well cuttings for a chemostratigraphic study. The aim was to identify opportunities for resource discovery in the Devonian-aged Adavale Basin in south-central Queensland by conducting a chemostratigraphic study to define regional stratigraphic correlations in a structurally complex basin with limited well penetrations. A total of 1,489 cutting samples were analysed for whole-rock geochemistry, as well as subsets of samples for whole-rock mineralogy and/or carbonate carbon and oxygen isotopes, from a whole-rock sample. The purpose was to establish new chemostratigraphic correlations across the basin independently, using data from 10 wells that sampled the Adavale Basin.</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>

Publicly available groundwater data have been compiled to provide a common information base to inform environmental, resource development and regulatory decisions in the Adavale Basin region. This data guide gives examples of how these data can be used. The data package included with this data guide captures existing knowledge of Eromanga Basin aquifers in the Adavale Basin region and their properties, including salinity, water levels, resource size, potential aquifer yield and surface water interactions. The methods used to derive these data for all Eromanga Basin aquifers in the Adavale Basin region are outlined in the associated metadata files. These are described in groundwater conceptual models (Gouramanis et al., 2023). The Eromanga Basin overlying the Adavale Basin includes 5 broadly defined aquifer intervals: from deepest to shallowest, these are the Poolowanna, Hutton, Adori, Cadna-owie–Hooray and Winton-Mackunda aquifers. Compiled data are assigned to these intervals and used to characterise groundwater systems at the basin scale. The data are compiled for a point-in-time to inform decisions on potential resource developments in the Basin. The available historical groundwater data can be used to assess the potential effects on groundwater. The data can also be used for other purposes, such as exploring unallocated groundwater resource potential. Data to January 2022 are used for this compilation.

The potential for hydrogen production in the Adavale Basin region is assessed to provide a joint information base for hydrogen generation potential from renewable energy, groundwater, and natural gas coupled with carbon capture and storage (CCS). Hydrogen generation requires water, whether using electrolysis with renewable energy or steam methane reforming (SMR) with CCS. The data package includes the regional renewable energy capacity factor, aquifers and their properties (potential yield, salinity, and reserves or storativity), natural gas resources, and geological storage potential for carbon dioxide (CO2). This data guide gives examples of how the compiled data can be used. The renewable hydrogen potential is assessed based on renewable energy capacity factor and groundwater information (potential yield, salinity, and reserves or storativity). Eight aquifers from overlying basins (Galilee, Eromanga and Lake Eyre basins) are included in the assessment. The Adavale Basin region has low renewable hydrogen potential, except for some locations in the south-east and south-west. Although the renewable energy capacity factor in the basin is high, aquifers tend to have poor groundwater reserves or storativity, which results in lower overall renewable hydrogen potential. The Adavale Basin itself has no newly identified gas accumulation. However, gas reserves and contingent resources were identified in the overlying Galilee and Eromanga basins (Geoscience Australia, 2022). An assessment of CO2 geological storage also shows prospective storage areas in the Eromanga Basin within the Adavale Basin region (Bradshaw et al., 2023). Further work on identifying detailed gas potential is needed to assess hydrogen generation potential from gas.

Publicly available groundwater data have been compiled to provide a common information base to inform environmental, resource development and regulatory decisions in the Adavale Basin region. This data guide gives examples of how these data can be used. The data package included with this data guide captures existing knowledge of Galilee Basin aquifers in the Adavale Basin region and their properties, including salinity, water levels, resource size, potential aquifer yield and surface water interactions. The methods to derive these data for all Galilee Basin aquifers in the Adavale Basin region are outlined in the associated metadata files. These are described in groundwater conceptual models (Gouramanis et al., 2023). The Galilee Basin overlying the Adavale Basin includes 3 broadly defined aquifer intervals: from deepest to shallowest, these are the Joe Joe Group, Betts Creek beds and Clematis aquifers. Compiled data have been assigned to these intervals and used to characterise groundwater systems at the basin scale. The data are compiled for a point-in-time to inform decisions on potential resource developments in the Basin. The available historical groundwater data can be used to assess the potential effects on groundwater. The data can also be used for other purposes, such as exploring unallocated groundwater resource potential. Data to January 2022 are used for this compilation.

Publicly available geology data are compiled to provide a common information base for resource development and regulatory decisions in the Adavale Basin region. This data guide gives examples of how the compiled data can be used. It supports a data package that presents core photographs, existing knowledge of the stratigraphy, and structural elements for the Adavale Basin and the overlying Galilee, Eromanga, Lake Eyre and other Cenozoic basins. Stratigraphic frameworks capture the geological groups and formations that make up the sedimentary sequence in the Adavale Basin region. The Adavale Basin includes 9 stratigraphic formations (Wainman et al., 2023). Overlying the Adavale Basin are the geological formations of the Galilee, Eromanga, Lake Eyre and other Cenozoic basins. The frameworks include the stratigraphic intervals used by the Trusted Environmental and Geological Information (TEGI) Program. From the base of the Adavale Basin to the top of overlying Cenozoic basins, the sedimentary sequence is categorised into 24 play intervals for resource assessment mapping and 12 hydrostratigraphic intervals for characterising groundwater systems (Wainman et al., 2023). Structural elements maps summarise where the sedimentary sequence has been deposited and later deformed by crustal movements. Structure information is used in assessing the geological potential for resources and interpreting groundwater flow and connectivity at the basin scale. The stratigraphic frameworks and structural elements provide the basic geological context for the Adavale Basin region resource and environmental assessments.