<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/)

<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/)

<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>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>

Publicly available data was compiled to provide a common information base for resource development, environmental and regulatory decisions in the Adavale Basin. This data guide gives an example of how these data can be used to create the components of a workflow to identify unconventional hydrocarbon resource opportunities. The data guide is designed to support the data package that provide insights on unconventional hydrocarbon resources in the Adavale Basin. The unconventional hydrocarbon assessment for the Adavale Basin includes tight gas, shale resources (shale oil and gas) and coal seam gas for 8 geological intervals, termed plays – these intervals have been defined by Wainman et al. (2023). The assessment captures data from well completion reports and government data sources (e.g. Queensland Petroleum Exploration Database (QPED) from the Geological Survey of Queensland (GSQ) Open Data Portal) along with the scientific literature to inform the components required for unconventional hydrocarbons to be present. Thirty-nine boreholes in the Adavale Basin were assessed with data used to map out gross depositional environments and their geological properties relevant for unconventional hydrocarbon assessments. The data are compiled at a point in time to inform decisions on resource development activities. The guide outlines the play-based workflow for assessing unconventional hydrocarbon resource prospectivity. Each of the elements required for a prospective unconventional hydrocarbon system is explained and mapped. These data were merged and spatially multiplied to show the relative assessment of unconventional hydrocarbon prospectivity across the basin, at both play interval and basin scale. As an example of assessments contained within the data package, this data guide showcases the tight gas prospectivity of the Buckabie Play interval.

Publicly available groundwater data have been compiled to inform environmental, resource development and regulatory decisions in the Adavale Basin region. This web service summarises salinity, water levels, resource size, potential aquifer yield and surface water–groundwater interactions for the Galilee Basin located within the Adavale Basin region.

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 web service summarises salinity, water levels, resource size, potential aquifer yield and surface water–groundwater interactions for the Lake Eyre Basin located within the Adavale Basin region.

<div>A prerequisite to understanding the evolution and resource potential of a basin is to establish a reliable stratigraphic framework that enables the correlation of rock units across multiple depocentres. Establishing a stratigraphic model for the Adavale Basin is challenging due to its structurally complexity, lack of well penetration and its lateral changes in facies. Biostratigraphy appears broad-scale, and despite providing chronostratigraphic control for the Lower Devonian Gumbardo Formation when combined with U/Pb zircon geochronology, the rest of the Devonian succession is hampered by a lack of microfossil assemblages and their poor preservation. The aim of this study is to establish an independent chemostratigraphic correlation across the Adavale Basin using whole rock inorganic geochemistry. Within this study, a total of 1489 cuttings samples from 10 study wells were analysed by Inductively Coupled Plasma – Optical Emission Spectrometry and Inductively Coupled Plasma – Mass Spectrometry for whole rock geochemistry, in order to establish an independent chemostratigraphic zonation scheme. Based on key elemental ratios selected to reflect changes in feldspars, clay minerals and provenance, the Devonian-aged stratigraphy is characterised into four chemostratigraphic mega-sequences that encompass the Gumbardo Formation (Mega-sequence 1); the Eastwood Formation, the Log Creek Formation and the Lissoy Sandstone (Mega-sequence 2); the Bury Limestone and the Boree Salt formations (Mega-sequence 3); and the Etonvale and the Buckabie formations (Mega-sequence 4). These mega-sequences have been further subdivided into a series of chemostratigraphic sequences that can be correlated across the study wells, establishing a regional correlation framework.&nbsp;&nbsp;&nbsp;</div> This Paper was submitted/presented to the 2023 Australian Petroleum Production & Exploration Association (APPEA) Conference 15-18 May, (https://www.appea.com.au/appea-event/appea-conference-and-exhibition-2023/). <b>Journal Citation:</b> Riley David, Pearce Tim, Davidson Morven, Sirantoine Eva, Lewis Chris, Wainman Carmine (2023) Application of elemental chemostratigraphy to refine the stratigraphy of the Adavale Basin, Queensland. <i>The APPEA Journal</i><b> 63</b>, 207-219. https://doi.org/10.1071/AJ22108

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 data was compiled to provide a common information base for resource development, and environmental and regulatory decisions in the Adavale Basin. This web service summarises the geological storage of carbon dioxide prospectivity of the Adavale Basin.