<div>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 a low emissions economy, strong 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, $225 m investment by the Australian Government. </div><div>As part of this program, Geoscience Australia led two deep crustal reflection seismic surveys in the South Nicholson region, revealing the existence of the Carrara Sub-basin, a large sedimentary depocentre up to 8 km deep, beneath the Georgina Basin (Carr et al., 2019; 2020). The depocentre is believed to contain thick sequences of highly prospective Proterozoic rocks for base metals and unconventional hydrocarbons. To confirm geological interpretations and assess resource potential, the National Drilling Initiative, NDI Carrara 1 stratigraphic drill hole was completed in late 2020, as a collaboration between Geoscience Australia, the Northern Territory Geological Survey (NTGS) and the MinEx CRC (Geoscience Australia, 2021). NDI Carrara 1 is located on the western flank of the Carrara Sub-basin on the South Nicholson seismic line (17GA-SN1) (Figure 1.1; Figure 1.2), reaching a total depth of 1751 m, intersecting sedimentary rocks comprising ca. 630 m of Cambrian calcareous shales of the Georgina Basin and ca. 1100 m of Proterozoic carbonates and siliciclastics that include black shales of the Carrara Sub-basin.</div><div>This report presents data on selected rock samples from NDI Carrara&nbsp;1, conducted by the Mawson Analytical Spectrometry Services, University of Adelaide, under contract to Geoscience Australia. These results include bulk carbon isotope ratios (δ13C) of bitumens and isolated kerogens. In addition, a selection of 10 samples was analysed at Geoscience Australia for comparison purposes.</div><div><br></div>

The Cooper Basin is a Pennsylvanian to Middle Triassic intracratonic basin in northeastern South Australia and southwestern Queensland (Gravestock et al., 1998; Draper, 2002; Carr et al., 2016). Exploration activity in the region has recently expanded with explorers pursuing a range of newly-identified unconventional hydrocarbon plays (Goldstein et al., 2012; Menpes et al., 2013; Greenstreet, 2015). In support of this ongoing exploration activity in the region, Hall et al. (2016a) reviewed the Cooper Basin source rock geochemistry and maturity based on a compilation of updated and quality controlled publically available total organic carbon (TOC), Rock-Eval pyrolysis and vitrinite reflectance data. This is the first study of its kind to be undertaken for the Cooper Basin as a whole and builds on the previous work of Boreham & Hill (1998) in South Australia. This data pack contains the supplementary material accompanying this report. The distribution, quantity, quality and thermal maturity of the organic matter were described for all formations within the Pennsylvanian¿Permian Gidgealpa Group and collectively for the formations within the Triassic Nappamerri Group (Hall et al., 2015a, 2016a). Where possible, data were also analysed by lithology. The total organic carbon (TOC) and Rock-Eval pyrolysis data were used to investigate source rock quality, maturity and kerogen type. Original Hydrogen Index (HIo) values for each formation and lithology were determined through the analysis of a subset of low maturity samples and through application of a maturity correction based on Cooper Basin-specific kinetics (Deighton et al., 2003; Mahlstedt et al., 2015). Where data density permits, maps of present day TOC content and both present day HI and original HI were created, showing the spatial variation in the amount and quality of the source rock present now and prior to the onset of hydrocarbon generation. This data pack includes all TOC and Rock Eval data for the Cooper Basin stratigraphic evaluated in Hall et al. (2016a). It also includes the grids of present day TOC for the shale and/or coaly shale intervals, along with the grids of present day and original HI by formation. These datasets quantify the spatial distribution, quantity and quality of the source rocks and provide important insights into the hydrocarbon prospectivity of the Cooper Basin (Hall et al., 2015b; Kuske et al., 2015). This was the first study to be completed as part of the Australian Petroleum Source Rock Mapping project, a new work program being undertaken at Geoscience Australia to improve our understanding of the petroleum resource potential of Australia's sedimentary basins.

<p>Geoscience Australia's Oracle organic geochemical database comprises analytical results for samples relevant to petroleum exploration, including source rocks, crude oils and natural gases collected across the Australian continent. The data comprises organic chemical analyses of hydrocarbon-bearing earth materials as well as including connectivity to some inorganic analyses. These data enable petroleum fluids to be typed into families and correlated to their source rock, from which depositional environment, age, and migration distances can be determined, and hence the extent of the total petroleum system can be mapped. This comprehensive data set is useful to government for evidence-based decision making on natural resources and the petroleum industry for de-risking conventional and unconventional petroleum exploration programs. <p>The data are produced by a wide range of analytical techniques. For example, source rocks are evaluated for their bulk compositional characteristics by programmed pyrolysis, pyrolysis-gas chromatography and organic petrology. Natural gases are analysed for their molecular and isotopic content by gas chromatography (GC) and gas chromatography-temperature conversion-mass spectrometry (GC-TC-IRMS). Crude oils and the extracts of source rocks are analysed for their bulk properties (API gravity; elemental analysis) and their molecular (biomarkers) and isotopic (carbon and hydrogen) content by GC, gas chromatography-mass spectrometry (GCMS) and GC-TC-IRMS. <p>The sample data originate from physical samples, well completion reports, and destructive analysis reports provided by the petroleum industry under the Offshore Petroleum and Greenhouse Gas Storage Act (OPGGSA) 2006 and previous Petroleum (submerged Lands) Act (PSLA) 1967. The sample data are also sourced from geological sampling programs in Australia by Geoscience Australia and its predecessor organisation's Australian Geological Survey Organisation (AGSO) and Bureau of Mineral Resources (BMR), and from the state and territory geological organisations. Geoscience Australia generates data from its own laboratories. Other open file data from publications, university theses and books are also included <b>Value:</b> The organic geochemistry database enables digital discoverability and accessibility to key petroleum geochemical datasets. It delivers open file, raw petroleum-related analytical results to web map services and web feature services in Geoscience Australia’s portal. Derived datasets and value-add products are created based on calculated values and geological interpretations to provide information on the subsurface petroleum prospectivity of the Australian continent. For example, the ‘Oils of Australia’ series and the ‘characterisation of natural gas’ reports document the location, source and maturity of Australia’s petroleum resources. Details of the total petroleum systems of selected basins studied under the Exploring for the Future project can be found in the Petroleum Systems Summaries Tool in Geoscience Australia’s portal. Related Geoscience Australia Records and published papers can be obtained from eCat. <b>Scope:</b> The collection initially comprised organic geochemical and petrological data on organic-rich sedimentary rocks, crude oils and natural gas from petroleum wells drilled in the onshore and offshore Australian continent. Over time, other sample types (ground water, fluid inclusions, mineral veins, bitumen) from other borehole types (minerals, stratigraphic – including the Integrated Ocean Drilling Program), marine dredge samples and field sites (outcrop, mines, surface seepage samples) have been analysed for their hydrocarbon content and are captured in the database. Results for many of the oil and gas samples held in the Australian National Offshore Wells Data Collection are included in this database.

The Otway Basin is a northwest-southeast trending rift basin which spans from onshore Victoria and South Australia into the deep-water offshore. The prospective supersequences within the basin are largely of Cretaceous age which host three possible petroleum systems (Austral 1, 2 and 3). While there is production from onshore depocentres, and the inboard Shipwreck Trough, the majority of the offshore basin remains underexplored. Recent regional studies have highlighted the need for further work across the underexplored parts of the basin and here we focus on the offshore northwest Otway Basin, integrating reinterpreted historical well data, newly acquired and recently reprocessed seismic data. This new Well Folio consists of composite logs and supporting data which includes interpreted lithologies, petrophysical analyses, the analysis of historic organic geochemistry and organic petrology. In addition, updated well markers are provided based on seismic interpretation and new biostratigraphy in key wells. This integrated study provides the basis for renewed prospectivity assessment in the northwest offshore portion of the Otway Basin.

<div>The pyrolysis-reflectance tie database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) schema and supporting oracle databases, which combine key properties related to thermal maturity. These data are typically used as input parameters in basin analysis and petroleum systems modelling to assist with the discovery and evaluation of sediment-hosted energy resources. The programmed pyrolysis analyses and the maceral reflectance analyses undertaken using reflected light microscopy are conducted on rock samples, either as cores, cuttings or rock chips, taken from boreholes and field sites in Australian sedimentary basins. The full datasets are available in the pyrolysis, vitrinite reflectance, maceral reflectance and organoclast maturity web services. These analyses are performed by various laboratories in service and exploration companies, Australian government institutions and universities using a range of instruments.</div><div><br></div><div>These data are collated from destructive analysis reports (DARs), well completion reports (WCRs), and literature. The data are delivered in the Combined Pyrolysis and Vitrinite Reflectance web services on the Geoscience Australia Data Discovery Portal at https://portal.ga.gov.au which will be periodically updated.</div>

<div>The Proterozoic basins of northern Australia have been the focus of regional hydrocarbon prospectivity studies undertaken by the Exploring for the Future&nbsp;program dedicated to increasing investment in resource exploration in northern Australia. As part of this program, a compilation of the compound-specific isotopic compositions of linear alkanes in source extracts, oils and oil stains from 21 boreholes&nbsp;of the greater McArthur Basin has been completed. The samples were analysed in Geoscience Australia’s Isotope and Organic Geochemistry Laboratory and the stable carbon and hydrogen isotopic data of individual alkanes are released in this report. </div>

<div>The Petroleum Systems Summary database stores the compilation of the current understanding of petroleum systems information by basin across Australia. The Petroleum Systems Summary database and delivery tool provide high-level information of the current understanding of key petroleum systems for areas of interest. For example, geological studies in the Exploring for the Future (EFTF) program have included the Canning, McArthur and South Nicholson basins (Carr et al., 2016; Hashimoto et al., 2018). The database and tool aim to assist geological studies by summarising and interpreting key datasets related to conventional and unconventional hydrocarbon exploration. Each petroleum systems summary includes a synopsis of the basin and key figures detailing the basin outline, major structural components, data availability, petroleum systems events chart and stratigraphy, and a précis of the key elements of source, reservoir and seal. Standardisation of petroleum systems nomenclature establishes a framework for each basin after Bradshaw (1993) and Bradshaw et al. (1994), with the source-reservoir naming conventions adopted from Magoon and Dow (1994).&nbsp;</div><div><br></div><div>The resource is accessible via the Geoscience Australia Portal&nbsp;(https://portal.ga.gov.au/) via the Petroleum Systems Summary Tool (Edwards et al., 2020).</div>

<div>The soil gas database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) schema and supporting oracle databases for gas analyses undertaken by Geoscience Australia's laboratory on soil samples taken from shallow (down to 1 m below the surface) percussion holes. Data includes the percussion hole field site location, sample depth, analytical methods and other relevant metadata, as well as the molecular and isotopic compositions of the soil gas with air included in the reported results. Acquisition of the molecular compounds are by gas chromatography (GC) and the isotopic ratios by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). The concentrations of argon (Ar), carbon dioxide (CO₂), nitrogen (N₂) and oxygen (O₂) are given in mole percent (mol%). The concentrations of carbon monoxide (CO), helium (He), hydrogen (H₂) and methane (C₁, CH₄) are given in parts per million (ppm). Compound concentrations that are below detection limit (BDL) are reported as the value -99999. The stable carbon (¹³C/¹²C) and nitrogen (¹⁵N/¹⁴N) isotopic ratios are presented in parts per mil (‰) and in delta notation as δ¹³C and δ¹⁵N, respectively.</div><div><br></div><div>Determining the individual sources and migration pathways of the components of natural gases found in the near surface are useful in basin analysis with derived information being used to support exploration for energy resources (petroleum and hydrogen) and helium in Australian provinces. These data are collated from Geoscience Australia records with the results being delivered in the Soil Gas web services on the Geoscience Australia Data Discovery portal at https://portal.ga.gov.au which will be periodically updated.</div>

<div>The Roebuck Basin on Australia’s offshore north-western margin is the focus of regional energy exploration activity. Drilling in the Roebuck Basin resulted in oil and gas discoveries at Phoenix South&nbsp;1 (2014), Roc&nbsp;1 (2015–2016) and Dorado&nbsp;1 (2018) in the Bedout Sub-basin (Figure 1‑2) and demonstrated the presence of a petroleum system in Lower Triassic strata. These discoveries have been evaluated for development and production with infill drilling at Roc&nbsp;2 (2016), Phoenix South&nbsp;2 (2016), Phoenix South&nbsp;3 (2018), Dorado&nbsp;2 (2019), and Dorado&nbsp;3 (2019). Recent drilling by Santos (2022) has resulted in the discovery of oil at Pavo&nbsp;1 (2022) and hydrocarbon shows at Apus&nbsp;1 (2022).</div><div><br></div><div>To complement this industry work, Geoscience Australia’s Offshore Energy Systems program produces pre-competitive information to assist with the evaluation of the energy and resource potential of the central North West Shelf, including both hydrogen and helium resources, and to attract exploration investment to Australia. As part of this program, determination of the molecular and noble gas isotopic composition of natural gases from selected petroleum wells in the Roebuck Basin were undertaken by Smart Gas Sciences, under contract to Geoscience Australia, with results from these analyses being released in this report. This report provides additional gas data to determine the sources of natural gases in the Roebuck Basin and build on previously established gas-gas correlations. Noble gas isotopic data can be used in conjunction with carbon and hydrogen isotopic data to determine the origin of both inorganic and organic (hydrocarbon) gases. This information can be used in future geological programs to determine the source and distribution of hydrogen and helium in natural gases and support acreage releases by the Australian Government.</div><div><br></div>

<div>The bulk oils database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) schema and supporting oracle databases for the bulk properties of petroleum liquids (e.g., condensate, crude oil, bitumen) sampled from boreholes and field sites. The analyses are performed by various laboratories in service and exploration companies, Australian government institutions, and universities using a range of instruments. Petroleum is composed primarily of hydrocarbons (carbon and hydrogen) with minor quantities of heterocyclic compounds containing either nitrogen, oxygen or sulfur. Data includes the borehole or field site location, sample depth, shows and tests, stratigraphy, analytical methods, other relevant metadata, and various data types including; API gravity, elemental composition and photographs of the samples. The stable carbon (¹³C/¹²C) and hydrogen (²H/¹H) isotopic ratios of crude oil and derivative saturated and aromatic hydrocarbon fractions are presented in parts per mil (‰) and in delta notation as &delta;¹³C and &delta;²H, respectively. Results are also included from methods that separate crude oils into bulk components, such as the quantification of saturated hydrocarbon, aromatic hydrocarbon, resin, and asphaltene (SARA) fractions according to their polarity.</div><div><br></div><div>These data provide information about the petroleum fluid’s composition, source, thermal maturity, secondary alteration, and fluid migration pathways. They are also useful for enhanced oil recovery assessments, petroleum systems mapping and basin modelling. Hence, these sample-based datasets are used for the discovery and evaluation of sediment-hosted resources. Some data are generated in Geoscience Australia’s laboratory and released in Geoscience Australia records. Data are also collated from destructive analysis reports (DARs), well completion reports (WCRs), and literature. The bulk oils data are delivered in the Petroleum Bulk Properties and Stable Isotopes web services on the Geoscience Australia Data Discovery Portal at https://portal.ga.gov.au which will be periodically updated.</div>