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 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 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>A regional hydrocarbon prospectivity assessment has been undertaken of the offshore Otway Basin by the Offshore Energy Systems Section. This program was designed to produce pre-competitive information to assist with the evaluation of the hydrocarbon resource potential of the offshore Otway Basin and attract exploration investment to Australia. The inboard part of the basin is an established hydrocarbon province with onshore and shallow-water offshore discoveries, whereas the outboard deep-water region, where water depths range from 500 to 6300&nbsp;m, is comparatively underexplored and considered a frontier area.</div><div><br></div><div>As part of this program, molecular and noble gas isotopic analyses were undertaken by Smart Gas Sciences, under contract to Geoscience Australia on available gas samples from the Waarre Formation in the Shipwreck Trough in the offshore eastern Otway Basin, with data from these analyses being released in this report. This report provides additional compositional information for gases in the Waarre Formation reservoirs and builds on previously established gas-gas correlations and gas-oil 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><br></div>

<div>The pyrolysis-gas chromatography database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) database and supporting oracle databases for open system pyrolysis-gas chromatography (pyrolysis-GC) analyses performed on either source rocks or kerogen samples taken from boreholes and field sites. Sedimentary rocks that contain organic matter are referred to as source rocks (e.g., organic-rich shale, oil shale and coal) and the organic matter within the rock matrix that is insoluble in organic solvents is named kerogen. The analyses are undertaken by various laboratories in service and exploration companies using a range of instruments. Data includes the borehole or field site location, sample depth, stratigraphy, analytical methods, other relevant metadata, and the molecular composition of the pyrolysates. The concentrations of the aliphatic hydrocarbon, aromatic hydrocarbon and organic sulfur compounds are given in several units of measure [e.g., percent (resolved compounds) in the S2 peak (wt% S2), milligrams per gram of rock (mg/g rock), micrograms per gram of kerogen (mg/g kerogen) etc.].</div><div><br></div><div>These data are used to determine the organic richness, kerogen type and thermal maturity of source rocks in sedimentary basins. The results are used as input parameters in basin analysis and petroleum systems modelling to evaluate the potential for hydrocarbon generation in a sedimentary basin. These data are collated from destructive analysis reports (DARs), well completion reports (WCRs) and literature. The data are delivered in the Source Rock Pyrolysis-Gas Chromatography web services on the Geoscience Australia Data Discovery Portal at https://portal.ga.gov.au which will be periodically updated.</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.

<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 onshore Canning Basin in Western Australia was the focus of a regional hydrocarbon prospectivity assessment undertaken by the Exploring for the Future&nbsp;(EFTF) program dedicated to increasing investment in resource exploration in northern Australia, with the objective being to acquire new data and information about the potential mineral, energy and groundwater resources concealed beneath the surface. Significant work has been carried out to deliver new pre-competitive data in the region including new seismic acquisition, drilling of a stratigraphic well, and geochemical analysis from historic exploration wells.</div><div><br></div><div>As part of this program, determination of the molecular and noble gas isotopic composition of natural gases from selected petroleum wells in the Canning 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 data to determine the sources of natural gases in the Canning Basin and build on the availability of existing gas data, gas-gas correlations and gas-oil 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 exploration programs.</div>

<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.

<div>The bulk source rock database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) schema and supporting oracle databases for the bulk properties of sedimentary rocks that contain organic matter and fluid inclusions taken 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. Sedimentary rocks that contain organic matter are typically referred to as source rocks (e.g., organic-rich shale, oil shale and coal) and the organic matter within the rock matrix that is insoluble in organic solvents is named kerogen. Data includes the borehole or field site location, sample depth, stratigraphy, analytical methods, other relevant metadata, and various data types including; elemental composition, and the stable isotopes of carbon, hydrogen, nitrogen, and sulfur. Results are also included from methods that separate the extractable organic matter (EOM) from rocks into bulk components, such as the quantification of saturated hydrocarbon, aromatic hydrocarbon, resin and asphaltene (SARA) fractions according to their polarity. The stable carbon (¹³C/¹²C) and hydrogen (²H/¹H) isotopic ratios of the EOM and derivative hydrocarbon fractions, as well as fluid inclusion oils, are presented in delta notation (i.e., &delta;¹³C and &delta;²H) in parts per mil (‰) relative to the Vienna Peedee Belemnite (VPDB) standard.</div><div><br></div><div>These data are used to determine the molecular and isotopic compositions of organic matter within rocks and associated fluid inclusions and evaluate the potential for hydrocarbon generation in a basin. 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 data for sedimentary rocks are delivered in the Source Rock 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>