<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>

<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>

In the 50 years since the first commercial discovery in 1965 at Barracouta-1, and 46 years since production commenced from the Barracouta field, a total of 16.5 TCF of gas, 4026 MMbbl of oil, 385 MMbbl of condensate and 752 MMbbl of LPG have been found in the Gippsland Basin (Estimated Ultimate Recovery, as at the end of 2012). Despite these extensive resources, all from CretaceousPaleogene Latrobe Group reservoirs, there are questions regarding the effective petroleum systems, contributing source rock units, and the migration pathways between source and reservoir. Resolution of these uncertainties is essential to improve our understanding of the remaining prospectivity and for creating new exploration opportunities, particularly in the eastern, less explored part of the basin, but also for mitigating risk for the potential sequestration of carbon dioxide along the southern and western flanks. Geochemical fingerprinting of reservoir fluids has identified that the oil and gas originate from multiple sources. The most pervasive hydrocarbon charge into the largely produced fields overlying the Central Deep has a terrestrial source affinity, originating from lower coastal plain facies (Kingfish, Halibut, Mackerel), yet the oils cannot be correlated using source-related biomarker parameters to source rocks either within the Halibut Subgroup (F. longus biozone) at Volador-1, one of the deepest penetrations of the Upper Cretaceous section, or to older sections, penetrated on the flanks of the basin. However, within the underlying SantonianCampanian Golden Beach Subgroup an oil-source correlation has been established between the Anemone-1A oil and the marginal marine Anemone Formation (N. senectus biozone) at Anemone-1/1A and Archer-1. A similar correlation is indicated for the Angler-1 condensate to the Chimaera Formation (T. lilliei biozone) in the deepest section at Volador-1 and Hermes-1. In the Longtom field, gas reservoired within the Turonian Emperor Subgroup, potentially has a source from either the lacustrine Kipper Shale or the Albian portion of the Strzelecki Group. The molecular and carbon isotopic signatures of oil and gas from the onshore Wombat field are most similar to hydrocarbons sourced from the AptianAlbian Eumeralla Formation in the Otway Basin, also implicating a Strzelecki source in the Gippsland Basin. These results imply that sediments older than the Paleocene are significant sources of petroleum within the basin. Presented at the the AAPG/SEG 2015 International Conference & Exhibition set in Melbourne

The Hera Au–Pb–Zn–Ag deposit in the southeastern Cobar Basin of central New South Wales preserves calc-silicate veins/skarn and remnant carbonate/sandstone-hosted skarn within a reduced anchizonal Siluro-Devonian turbidite sequence. The skarn orebody distribution is controlled by a long-lived, basin margin fault system, that has intersected a sedimentary horizon dominated by siliciclastic turbidite, with lesser gritstone and thick sandstone intervals, and rare carbonate-bearing stratigraphy. Foliation (S1) envelopes the orebody and is crosscut by a series of late-stage east–west and north–south trending faults. Skarn at Hera displays mineralogical zonation along strike, from southern spessartine–grossular–biotite–actinolite-rich associations, to central diopside-rich–zoisite–actinolite/tremolite–grossular-bearing associations, through to the northern most tremolite–anorthite-rich (garnet-absent) association in remnant carbonate-rich lithologies and sandstone horizons; the northern lodes also display zonation down dip to garnet present associations at depth. High-T skarn assemblages are pervasively retrogressed to actinolite/tremolite–biotite-rich skarn and this retrograde phase is associated with the main pulse of sulfide mineralisation. The dominant sulfides are high-Fe-Mn sphalerite–galena–non-magnetic high-Fe pyrrhotite–chalcopyrite; pyrite, arsenopyrite and scheelite are locally abundant. The distribution of metals in part mimics the changing gangue mineralogy, with Au concentrated in the southern and lower northern lode systems and broadly inverse concentrations for Ag–Pb–Zn. Stable isotope data (O–H–S) from skarn amphiboles and associated sulfides are consistent with magmatic/basinal water and magmatic sulfur inputs, while hydrosilicates and sulfides from the wall rocks display elevated δD and mixed δ34S consistent with progressive mixing or dilution of original basinal/magmatic waters within the Hera deposit by unexchanged waters typical of low latitude (tropical) meteoritic waters. High precision titanite (U–Pb) and biotite (Ar–Ar) geochronology reveals a manifold orebody commencing with high-T skarn and retrograde Pb–Zn-rich skarn formation at ≥403 Ma, Au–low-Fe sphalerite mineralisation at 403.4 ± 1.1 Ma, foliation development remobilisation or new mineralisation at 390 ± 0.2 Ma followed by thrusting, orebody dismemberment at (384.8 ± 1.1 Ma) and remobilization or new mineralisation at 381.0 ± 2.2 Ma. The polymetallic nature of the Hera orebody is a result of multiple mineralizing events during extension and compression and involving both magmatic and likely basinal fluid/metal sources. <b>Citation:</b> Fitzherbert, Joel A., McKinnon, Adam R., Blevin, Phillip L., Waltenberg, Kathryn., Downes, Peter M., Wall, Corey., Matchan, Erin., Huang Huiqin., The Hera orebody: A complex distal (Au–Zn–Pb–Ag–Cu) skarn in the Cobar Basin of central New South Wales, Australia <i>Resource Geology,</i> Vol 71, Iss 4, pp296-319 <b>2021</b>. DOI: https://doi.org/10.1111/rge.12262

<div>The bulk rock stable isotopes database table contains publicly available results from Geoscience Australia's organic geochemistry (ORGCHEM) schema and supporting oracle databases for the stable isotopic composition of sedimentary rocks with an emphasis on calcareous rocks and minerals sampled from boreholes and field sites. The stable isotopes of carbon, oxygen, strontium, hydrogen, nitrogen, and sulfur are measured by various laboratories in service and exploration companies, Australian government institutions, and universities, using a range of instruments. Data includes the borehole or field site location, sample depth, stratigraphy, analytical methods, other relevant metadata, and the stable isotopes ratios. The carbon (¹³C/¹²C) and oxygen (¹⁸O/¹⁶O) isotope ratios of calcareous rocks are expressed in delta notation (i.e., &delta;¹³C and &delta;¹⁸O) in parts per mil (‰) relative to the Vienna Peedee Belemnite (VPDB) standard, with the &delta;¹⁸O values also reported relative to the Vienna Standard Mean Ocean Water (VSMOW) standard. Likewise, the stable isotope ratio of hydrogen (²H/¹H) is presented in delta notation (&delta;²H) in parts per mil (‰) relative to the VSMOW standard, the stable isotope ratio of nitrogen (¹⁵N/¹⁴N) is presented in delta notation (&delta;¹⁵N) in parts per mil (‰) relative to the atmospheric air (AIR) standard, and the stable isotope ratio of sulfur (³⁴S/³²S) is presented in delta notation (&delta;³⁴S) relative to the Vienna Canyon Diablo Troilite (VCDT) standard. For carbonates, the strontium (⁸⁷Sr/⁸⁶Sr) isotope ratios are also provided.</div><div><br></div><div>These data are used to determine the isotopic compositions of sedimentary rock with emphasis on the carbonate within rocks, either as minerals, the mineral matrix or cements. The results for the carbonate rocks are used to determine paleotemperature, paleoenvironment and paleoclimate, and establish regional- and global-scale stratigraphic correlations. These data are collated from Geoscience Australia records, destructive analysis reports (DARs), well completion reports (WCRs), and literature. The stable isotope data for sedimentary rocks are delivered in the Stable Isotopes of Carbonates web services on the Geoscience Australia Data Discovery Portal at https://portal.ga.gov.au which will be periodically updated.</div>

Australia is about to become the premier global exporter of liquefied natural gas (LNG), bringing increased opportunities for helium extraction. Processing of natural gas to LNG necessitates the exclusion and disposal of nonhydrocarbon components, principally carbon dioxide and nitrogen. Minor to trace hydrogen, helium and higher noble gases in the LNG feed-in gas become concentrated with nitrogen in the non-condensable LNG tail gas. Helium is commercially extracted worldwide from this LNG tail gas. Australia has one helium plant in Darwin where gas (containing 0.1% He) from the Bayu-Undan accumulation in the Bonaparte Basin is processed for LNG and the tail gas, enriched in helium (3%), is the feedstock for helium extraction. With current and proposed LNG facilities across Australia, it is timely to determine whether the development of other accumulations offers similar potential. Geoscience Australia has obtained helium contents in ~800 Australian natural gases covering all hydrocarbon-producing sedimentary basins. Additionally, the origin of helium has been investigated using the integration of helium, neon and argon isotopes, as well as the stable carbon (13C/12C) isotopes of carbon dioxide and hydrocarbon gases and isotopes (15N/14N) of nitrogen. With no apparent loss of helium and nitrogen throughout the LNG industrial process, together with the estimated remaining resources of gas accumulations, a helium volumetric seriatim results in the Greater Sunrise (Bonaparte Basin) > Ichthys (Browse Basin) > Goodwyn–North Rankin (Northern Carnarvon Basin) accumulations having considerably more untapped economic value in helium extraction than the commercial Bayu-Undan LNG development.

<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>