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  • This report presents the results of chemostratigraphic analyses for samples of the Waukarlycarly 1 deep stratigraphic well drilled in in the Waukarlycarly Embayment of the Canning Basin. The drilling of the well was funded by Geoscience Australia’s Exploring for the Future initiative to improve the understanding of the sub-surface geology of this underexplored region of the southern Canning Basin. The well was drilled in partnership with Geological Survey of Western Australia (GSWA) as project operator. Waukarlycarly 1 reached a total depth (TD) of 2680.53 m at the end of November 2019 and was continuously cored from 580 mRT to TD. The work presented in this report constitutes part of the post-well data acquisition. An elemental and isotope chemostratigraphic study was carried out on 100 samples of the well to enable stratigraphic correlations to be made across the Canning Basin within the Ordovician section known to host source rocks. Nine chemostratigraphically distinct sedimentary packages are identified in the Waukarlycarly 1 well and five major chemical boundaries that may relate to unconformities, hiatal surfaces or sediment provenance changes are identified. The Ordovician sections in Waukarlycarly 1 have different chemical signals in comparison to those in other regional wells, suggestive of a different provenance for the origin of the sediments in the Waukarlycarly Embayment compared to the Kidson Sub-basin (Nicolay 1) and Broome Platform (Olympic 1).

  • <div>This report contains new whole-rock and isotope (Pb and Sr) geochemical data, associated sample metadata, an assessment of the data’s quality assurance, for 76 samples collected from the Georgina Basin of the East Tennant National Drilling Initiative (NDI) in 2021. The data can be downloaded via the Geoscience Australia EFTF portal (https://portal.ga.gov.au/persona/eftf) or in the files attached with this record (http://pid.geoscience.gov.au/dataset/ga/148954).</div><div><br></div><div>This new geochemistry data release builds on the success of the East Tennant NDI, addressing the data-gap in earlier geochemical sampling of these holes, by providing whole-rock geochemistry (and Pb+Sr isotopes) for the Georgina Basin cover sequence. Improved geochemical characterisation of Georgina Basin geology is valuable from both a hydrogeological and mineral systems perspective. The Georgina Basin extends across much of the Northern Territory and into western Queensland, comprised of Cryogenian to Devonian sediment packages.</div><div><br></div><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 net zero emissions, strong, sustainable 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, $225m investment by the Australian Government.</div><div><br></div>

  • Paleoproterozoic arc and backarc assemblages accreted to the south Laurentian margin between 1800 Ma and 1600 Ma, and previously thought to be indigenous to North America, more likely represent fragments of a dismembered marginal sea developed outboard of the formerly opposing Australian-Antarctic plate. Fugitive elements of this arc-backarc system in North America share a common geological record with their left-behind Australia-Antarctic counterparts, including discrete peaks in tectonic and/or magmatic activity at 1780 Ma, 1760 Ma, 1740 Ma, 1710-1705 Ma, 1690-1670 Ma, 1650 Ma and 1620 Ma. Subduction rollback, ocean basin closure and the arrival of Laurentia at the Australian-Antarctic convergent margin first led to arc-continent collision at 1650-1640 Ma and then continent-continent collision by 1620 Ma as the last vestiges of the backarc basin collapsed. Collision induced obduction and transfer of the arc and more outboard parts of the Australian-Antarctic backarc basin onto the Laurentian margin where they remained following later breakup of the Neoproterozoic Rodinia supercontinent. North American felsic rocks generally yield Nd depleted mantle model ages consistent with arc and backarc assemblages built on early Paleoproterozoic Australian crust as opposed to older Archean basement making up the now underlying Wyoming and Superior cratons. Appeared in Lithosphere (2019) 11 (4): 551–559, June 10, 2019.

  • <b>Legacy service Retired 29/11/2022 IMPORTANT NOTICE: </b>This web service has been deprecated. The Australian Onshore and Offshore Boreholes OGC service at https://services.ga.gov.au/gis/boreholes/ows should now be used for accessing Geoscience Australia borehole data. This is an Open Geospatial Consortium (OGC) web service providing access to Australian onshore and offshore borehole data. This web service is intended to complement the borehole GeoSciML-Portrayal v4.0 web service, providing access to the data in a simple, non-standardised structure. The borehole data includes Mineral Drillholes, Petroleum Wells and Water Bores along with a variety of others types. The dataset has been restricted to onshore and offshore Australian boreholes, and bores that have the potential to support geological investigations and assessment of a variety of resources.

  • The Exploring for the Future (EFTF) program is an Australian government initiative to boost investment in resource exploration and development in Australia, and is committed to supporting a strong economy, resilient society and sustainable environment for the benefit of Australians. There are a number of interrelated projects within the EFTF, including the Australia’s Resources Framework (ARF) project. The latter is a continental-scale project aimed at laying the foundations for a national view of Australia’s surface and subsurface geology, to underpin our understanding of the continent’s mineral, energy and groundwater potential. The ARF project involves new, large-scale data acquisition, advances in big data analytics and tailored resource assessments, to support the resource sector, agriculture, remote communities and the environment, and contribute to community safety. As part of ARF, Geoscience Australia has been undertaking studies of Australian basins that are prospective for, or have potential for, basin-hosted base metal mineral systems (Pb-Zn, Co-Cu), as part of the basins module. The first component of this module (2016-2020) investigated the Paleoproterozoic to Mesoproterozoic greater McArthur Basin system, Northern Territory and western Queensland (Champion et al., 2020 a, b, c; Huston et al. 2020). The 2020-2024 module is focusing on the Neoproterozoic part of the Stuart Shelf region of the Adelaide Superbasin, South Australia. The Paleo- to Mesoproterozoic sedimentary and volcanic sequences of the Mount Isa–McArthur Basin region of Northern Territory and Queensland are host to a range of world class mineral deposits (Hutton et al., 2012) and include the basin-hosted base metal deposits of the North Australian Zinc Belt, the world’s richest belt of zinc deposits (Huston et al., 2006; Large et al., 2005). These syngenetic (and epigenetic) basin-hosted mineral deposits include McArthur River (formerly HYC) and Century lead-zinc (Pb-Zn) deposits, the Walford Creek Zn-Pb-Cu-Ag deposit (Rohrlach et al., 1998; Large et al., 2005; Hutton et al. 2012) and the Redbank Cu deposit (Knutson et al. 1979). The Neoproterozoic sedimentary sequences of the Stuart Shelf, and their continuation into the Torrens Hinge Zone and Adelaide Rift Complex (Adelaide Superbasin), South Australia, are host to, or form an integral part of, a number of, often historically important, deposits, including the first copper mining region in Australia. These include, amongst others, the Kapunda, Mt Gunson, Cattle Grid, MG14, Windabout, Myall Creek, and Emmie Bluff copper deposits (Lambert et al. 1980, 1984, 1985 1987; Knutson et al. 1983; Coda Minerals 2020, 2021). These deposits are hosted within the Neoproterozoic sediments or along the basal unconformity with older Mesoproterozoic clastic sedimentary rocks (Lambert et al. 1987). This report contains reanalysed geochemical data, and associated sample metadata, for legacy samples collected by the Baas Becking laboratories in the 1970’s from deposits and surrounds in the MacArthur Basin and Stuart Shelf region. This includes samples (mafic igneous rocks, mineralised samples and sedimentary rocks) from the Redbank Cu deposit and surrounds in the McArthur Basin, partly documented in Knutson et al. (1979); samples (sediments, mafic igneous rocks including basement volcanic units (Gawler Range Volcanics), and mineralised samples) from the Mt Gunson deposit and surrounds (Mt Gunson-Lake Dutton area) documented in Knutson et al. (1983, 1992); and a small subset of five samples (sediments, variably mineralised) from the Myall Creek prospect, documented in Lambert et al. (1984). The great majority of these samples are from drill core, with the full list of samples analyses and metadata listed in Appendix A and summarised in Table 1. This data release also includes 52 samples from the Killi Killi Hills regions and surrounds, Tanami, Northern Territory (jobno 9004424), collected by the NTGS and GA, and originally analysed, in the early 1990’s and early 2000’s. These samples included a subset of P2O5-Sr-HREE-enriched Gardiner Sandstone samples from the Killi Killi Hills prospect. These samples are not directly related to the basins project but have been included as they were analysed at the same time as the Stuart Shelf and Redbank samples, and they increase the number of samples and the range of rock types analysed, and so help with statistics for QA/QC purposes. All geochemical data are provided in the appendices, listed by batch. The data can be downloaded via the Geoscience Australia EFTF portal (https://portal.ga.gov.au/persona/eftf).

  • The Paleo- to Mesoproterozoic McArthur Basin and Mount Isa region of northern Australia (Figure 1) is richly-endowed with a range of deposit types (e.g., Ahmad et al., 2013; Geological Survey of Queensland, 2011). These include the basin-hosted base metal (Zn-Pb-Ag) deposits of the North Australian Zinc Belt, the richest zinc province in the world (Geological Survey of Queensland, 2011; Huston et al., 2006), as well as Cu (e.g., Mt Isa Copper) and IOCG (e.g., Ernest Henry) deposits (Geological Survey of Queensland, 2011). The giant size of the base metal deposits makes them attractive exploration targets and significant effort has been undertaken in understanding their genesis and setting and developing methodologies and data sets to aid in further discovery. As part of its Exploring for the Future program, Geoscience Australia is acquiring new, and reprocessing old, data sets to provide industry with new exploration tools for these basin-hosted Zn-Pb and Cu deposits, as well as iron-oxide copper-gold deposits. We have adopted a mineral systems approach (e.g., Huston et al., 2016) focussing on regional aspects such as source rocks, locations of mineral deposits, mineralisation haloes and footprints. Increased understanding of these aspects requires knowledge of the background variability of unaltered rocks within the basin. To assist in this we have undertaken a campaign of baseline geochemical studies, with over 800 new samples collected from sedimentary and igneous units of selected parts of the greater McArthur Basin–Mount Isa region. This has allowed us to document temporal and regional background geochemical (and mineralogical) variation within, and between sedimentary and igneous units. The main focus of this work was directed towards aspects of base metal mineralisation; a concurrent GA study (e.g., Jarrett et al., 2019) looking at aspects of hydrocarbon potential was undertaken in parallel. Appeared in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory 24-25 March 2020, p. 105

  • This database contains geochemical data for samples analysed both for inorganic and organic geochemistry. Analytical data are sourced from Geoscience Australia's Inorganic Geochemistry Database (OZCHEM) and Organic Geochemistry Database (ORGCHEM), respectively. The data are joined on a unique sample number. Inorganic geochemical data cover the majority of the periodic table, with metadata on analytical methods and detection limits. Organic geochemical data include results of pyrolysis, derivative calculated values, and, where available, isotopic composition of carbonates (D13C) and isotopic composition of rock nitrogen (D15N). Further, there are provisions for delivery of isotopic data for kerogen (H, C, N) and oxygen (O) for carbonates. Where available, sample descriptions include stratigraphic unit names and ages, and lithology. Location information includes coordinates of the sampled feature (eg, borehole), coordinates of the sample and sample depth. Interpretation of the combined inorganic and organic geochemistry for organic-rich shales will facilitate comprehensive characterisation of hydrocarbons source rocks and mineral commodities source and trap environments. All are achieved within the frameworks of petroleum and mineral systems analysis. The initial data delivered by this service include 1785 samples from 35 boreholes from 14 geological provinces, including recently released data for 442 samples from the South Nicholson National Drilling Initiative Carrara 1 stratigraphic drill hole (Butcher et al., 2021; Carson et al., 2021). Many sampled boreholes are located within the polygon of the Exploring for the Future Barkly-Isa-Georgetown project. This dataset will be updated periodically as more data become available.

  • Manuscript detailing the results of chlorite dissolution experiments conducted at Geoscience Australia.

  • Geoscience Australia and its predecessors have analysed hydrochemistry of water sampled from boreholes (both pore water and groundwater), surface features, and rainwater. Sampling was undertaken during drilling or monitoring projects, and this dataset represents a significant subset of stored analyses. Water chemistry including isotopic data is essential to better understand groundwater origins, ages and dynamics, processes such as recharge and inter-aquifer connectivity and for informing conceptual and numerical groundwater models. This GA dataset underpins a nationally consistent data delivery tool and web-based mapping to visualise, analyse and download groundwater chemistry and environmental isotope data. This dataset is a spatially-enabled groundwater hydrochemistry database based on hydrochemistry data from projects completed in Geoscience Australia. The database includes information on physical-chemical parameters (EC, pH, redox potential, dissolved oxygen), major and minor ions, trace elements, nutrients, pesticides, isotopes and organic chemicals. Basic calculations for piper plots colours are derived from Peeters, 2013 - A Background Color Scheme for Piper Plots to Spatially Visualize Hydrochemical Patterns - Groundwater, Volume 52(1) <https://doi.org/10.1111/gwat.12118>. Upon loading the data to the database, all hydrochemistry data are assessed for reliability using Quality Assurance/Quality Control procedures and all datasets were standardised. This data is made accessible with open geospatial consortium (OGC) web services and is discoverable via the Geoscience Australia Portal (<a href="https://portal.ga.gov.au/">https://portal.ga.gov.au/</a>). This dataset is published with the permission of the CEO, Geoscience Australia.

  • As part of the Exploring for the Future (EFTF) program, a chemostratigraphic framework for the Officer Basin was developed that correlates inorganic geochemical sequences between exploration wells. The Officer Basin spans 525,000 km<sup>2</sup> across Western Australia and South Australia, where it remains an unproven frontier basin which has seen little exploration. The objective of this study was to undertake a bulk rock elemental chemostratigraphy study on ten historic wells in order to better correlate the Neoproterozoic and Cambrian sections. Ten study wells, five from Western Australia and five from South Australia, were selected, and core (241) and cuttings (1,245) samples were acquired from their respective state core libraries. All samples were analysed using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), resulting in quantitative data for 50 elements. The approximate proportions of dolomite, clastics, halite and anhydrite for the samples were derived using stoichiometric geochemical calculations. Halite was identified in some formations based on mud log and wireline data, but was not always preserved in the cuttings samples. This non-detection of halite resulted in poor matches between the wireline gamma ray (GR) and ChemGR profiles for halite-bearing units in some wells (e.g. Dragoon-1, Mulyawara-1, and Yowalga-3). Key element and ratios utilised to subdivide the strata were principally chosen to highlight changes in sediment provenance, climatic, and organic matter changes, as they typically have the best correlation potential over a greater distance. The stratigraphy within the study wells has been subdivided into eight chemostratigraphic mega-sequences referred to as MS1 to MS8, which are further subdivided into a total of twenty-four sequences. Mega-Sequences MS1 to MS4 broadly correspond to the published Neoproterozoic–Cambrian Centralian Supersequences (CS1 to CS4). While overall there is broad agreement between these two schemes, there are also sections where the stratigraphy has been reassigned. For example, within Kutjara-1, the section previously assigned to Centralian Supersequence CS2, and equivalent to the Cryogenian Tapley Hill Formation, is assigned to Mega-Sequence MS3 (not MS2). Within MS4, the lithostratigraphically defined members of the Observatory Hill Formation show some significant variation to the chemostratigraphy, with differences occurring within sequences MS4-S3, MS4-S4 and MS4-S5 (e.g. Birksgate-1; Trainor Echo-1). Mega-Sequence MS6 encompasses the Mount Chandler Sandstone in Trainor Echo-1 in the east and the lithological lateral equivalent Lennis Sandstone in Lungkarta-1/ST1 and Yowalga-1 in the west; however, these two argillaceous sandstones are chemically distinct. Carbonate-containing samples from three wells (Birksgate-1, Yowalga-3, and Giles-1) were analysed for their δ13Ccarb and δ18Ocarb isotope signature using Isotope-Ratio Mass Spectrometry (IRMS), with results from the least altered carbonates being of sufficient quality to attempt preliminary age dating. Comparison of the Officer Basin isotope data to global type sections enabled tentative correlation of the Yowalga-3 carbonates to the Tonian and late Ediacaran, and the Birksgate-1 carbonates to the early Cambrian. The geochemistry analyses from 10 basin-wide wells provide a robust dataset that has been used to confirm which sections correlate within the existing lithostratigraphic and sequence stratigraphic framework. This study also highlights where further work needs to be undertaken to elucidate the spatial and temporal relationships of some Cryogenian and early Cambrian sections across the entire basin, given that rocks of these ages contain both potential source and reservoir rocks for petroleum generation and accumulation.