<b>Organic Geochemistry (ORGCHEM) Schema. Australian Source Rock and Fluid Atlas</b> The databases tables held within Geoscience Australia's Oracle Organic Geochemistry (ORGCHEM) Schema, together with other supporting Oracle databases (e.g., Borehole database (BOREHOLE), Australian Stratigraphic Units Database (ASUD), and the Reservoir, Facies and Shows (RESFACS) database), underpin the Australian Source Rock and Fluid Atlas web services and publications. These products provide information in an Australia-wide geological context on organic geochemistry, organic petrology and stable isotope data related primarily to sedimentary rocks and energy (petroleum and hydrogen) sample-based datasets used for the discovery and evaluation of sediment-hosted resources. The sample data provide the spatial distribution of source rocks and their derived petroleum fluids (natural gas and crude oil) taken from boreholes and field sites in onshore and offshore Australian provinces. Sample depth, stratigraphy, analytical methods, and other relevant metadata are also supplied with the analytical results. 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 data in the ORGCHEM schema are produced by a wide range of destructive analytical techniques conducted on samples submitted by industry under legislative requirements, as well as on samples collected by research projects undertaken by Geoscience Australia, state and territory geological organisations and scientific institutions including the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and universities. Data entered into the database tables are commonly sourced from both the basic and interpretive volumes of well completion reports (WCR) provided by the petroleum well operator to either the state and territory governments or, for offshore wells, to the Commonwealth Government under the Offshore Petroleum and Greenhouse Gas Storage Act (OPGGSA) 2006 and previous Petroleum (submerged Lands) Act (PSLA) 1967. Data are also sourced from analyses conducted by Geoscience Australia’s laboratory and its predecessor organisations, the Australian Geological Survey Organisation (AGSO) and the Bureau of Mineral Resources (BMR). Other open file data from company announcements and reports, scientific publications and university theses are captured. The ORGCHEM database was created in 1990 by the BMR in response to industry requests for organic geochemistry data, featuring pyrolysis, vitrinite reflectance and carbon isotopic data (Boreham, 1990). Funding from the Australian Petroleum Cooperative Research Centre (1991–2003) enabled the organic geochemical data to be made publicly available at no cost via the petroleum wells web page from 2002 and included BOREHOLE, ORGCHEM and the Reservoir, Facies and Shows (RESFACS) databases. Investment by the Australian Government in Geoscience Australia’s Exploring for the Future (EFTF) program facilitated technological upgrades and established the current web services (Edwards et al., 2020). The extensive scope of the ORGCHEM schema has led to the development of numerous database tables and web services tailored to visualise the various datasets related to sedimentary rocks, in particular source rocks, crude oils and natural gases within the petroleum systems framework. These web services offer pathways to access the wealth of information contained within the ORGCHEM schema. Web services that facilitate the characterisation of source rocks (and kerogen) comprise data generated from programmed pyrolysis (e.g., Hawk, Rock-Eval, Source Rock Analyser), pyrolysis-gas chromatography (Py-GC) and kinetics analyses, and organic petrological studies (e.g., quantitation of maceral groups and organoclasts, vitrinite reflectance measurements) using reflected light microscopy. Collectively, these data are used to establish the occurrence of source rocks and the post-burial thermal history of sedimentary basins to evaluate the potential for hydrocarbon generation. Other web services provide data to characterise source rock extracts (i.e., solvent extracted organic matter), fluid inclusions and petroleum (e.g., natural gas, crude oil, bitumen) through the reporting of their bulk properties (e.g., API gravity, elemental composition) and molecular composition using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Also reported are the stable isotope ratios of carbon, hydrogen, nitrogen, oxygen and sulfur using gas chromatography-isotope ratio mass spectrometry (GC-IRMS) and noble gas isotope abundances using ultimate high-resolution variable multicollection mass spectrometry. The stable isotopes of carbon, oxygen and strontium are also reported for sedimentary rocks containing carbonate either within the mineral matrix or in cements. Interpretation of these data enables the characterisation of petroleum source rocks and identification of their derived petroleum fluids, which comprise two key elements of petroleum systems analysis. Understanding a fluid’s physical properties and molecular composition are prerequisites for field development. The composition of petroleum determines its economic value and hence why the concentration of hydrocarbons (methane, wet gases, light and heavy oil) and hydrogen, helium and argon are important relative to those of nitrogen, carbon dioxide and hydrogen sulfide for gases, and heterocyclic compounds (nitrogen, oxygen or sulfur) found in the asphaltene, resin and polar fractions of crude oils. The web services and tools in the Geoscience Australia Data Discovery Portal (https://portal.ga.gov.au/), and specifically in the Source Rock and Fluid Atlas Persona (https://portal.ga.gov.au/persona/sra), allow the users to search, filter and select data based on various criteria, such as basin, formation, sample type, analysis type, and specific geochemical parameters. The web map services (WMS) and web feature services (WFS) enable the user to download data in a variety of formats (csv, Json, kml and shape file). The Source Rock and Fluid Atlas supports national resource assessments. The focus of the atlas is on the exploration and development of energy resources (i.e., petroleum and hydrogen) and the evaluation of resource commodities (i.e., helium and graphite). Some data held in the ORGCHEM tables are used for enhanced oil recovery and carbon capture, storage and utilisation projects. The objective of the atlas is to empower people to deliver Earth science excellence through data and digital capability. It benefits users who are interested in the exploration and development of Australia's energy resources by: • Providing a comprehensive and reliable source of information on the organic geochemistry of Australian source rocks • Enhancing the understanding of the spatial distribution, quality, and maturity of petroleum source rocks. • Facilitating the mapping of total petroleum and hydrogen systems and the assessment of the petroleum and hydrogen resource potential and prospectivity of Australian basins. • Facilitating the mapping of gases (e.g., methane, helium, carbon dioxide) within the geosphere as part of the transition to clean energy. • Enabling the integration and comparison of data from diverse sources and various acquisition methods, such as geological, geochemical, geophysical and geospatial data. • Providing data for integration into enhanced oil recovery and carbon capture, storage and utilisation projects. • Improving the accessibility and usability of data through user-friendly and interactive web-based interfaces. • Promoting the dissemination and sharing of data among Government, industry and community stakeholders. <b>References</b> Australian Petroleum Cooperative Research Centre (APCRC) 1991-2003. Australian Petroleum CRC (1991 - 2003), viewed 6 May 2024, https://www.eoas.info/bib/ASBS00862.htm and https://www.eoas.info/biogs/A001918b.htm#pub-resources Boreham, C. 1990. ORGCHEM Organic geochemical database. BMR Research Newsletter 13. Record 13:10-10. Geoscience Australia, Canberra. https://pid.geoscience.gov.au/dataset/ga/90326 Edwards, D.S., MacFarlane, S., Grosjean, E., Buckler, T., Boreham, C.J., Henson, P., Cherukoori, R., Tracey-Patte, T., van der Wielen, S.E., Ray, J., Raymond, O. 2020. Australian source rocks, fluids and petroleum systems – a new integrated geoscience data discovery portal for maximising data potential. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/133751. <b>Citation</b> Edwards, D., Buckler, T. 2024. Organic Geochemistry (ORGCHEM) Schema. Australian Source Rock and Fluid Atlas. Geoscience Australia, Canberra. https://pid.geoscience.gov.au/dataset/ga/149422

<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>This study was commissioned by Geoscience Australia (GA) as part of the Exploring for the Future program to produce a report on the organic petrology for rock samples from drill holes of the Birrindudu Basin, Northern Territory, Australia. A suite of 130 drill core samples from 6 drill holes was analysed using standard organic petrological methods to identify the types of organic matter present, assess their relative abundances and determine the levels of thermal maturity attained by the sedimentary organic matter using the reflectance of organoclasts present. </div>

This Geoscience Australia Record reports the findings of the Canning Basin Petroleum Systems Modelling Project. The southern, frontier portions of the Canning Basin have numerous potential hydrocarbon play opportunities, in particular unconventional gas plays, which remain untested. Of particular interest are Ordovician-aged petroleum systems. Geoscience Australia in collaboration with the Geological Survey of Western Australia acquired an 872 km long 2D seismic line across the south and south-west Canning Basin in 2018, and drilled the 2680 m stratigraphic hole Barnicarndy 1 in the Barnicarndy Graben to further develop the understanding of hydrocarbon prospectivity in these frontier regions. As part of the Exploring for the Future program Geoscience Australia contracted GNS Science to construct ten 1D petroleum systems models and one 2D model across the frontier southern parts of the basin. The aim was to combine interpretation of the newly acquired seismic data with interpretation of legacy and new well data, in particular organic geochemical data, to improve the understanding of the burial and thermal history, trap formation, generation and migration of hydrocarbons in the southern, frontier parts of the Canning Basin. This Record is a compilation of the work completed by GNS Science International Limited and the reports containing new data collected and analyzed relevant to the petroleum systems modelling.