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  • A benthic sediment sampling survey (GA0356) to the nearshore areas of outer Darwin Harbour was undertaken in the period from 03 July to 14 September 2016. Partners involved in the survey included Geoscience Australia (GA), the Australian Institute of Marine Science (AIMS) and the Department of Environment and Natural Resources within the Northern Territory Government (NT DENR) (formerly the Department of Land and Resource Management (DLRM)). This survey forms part of a four year (2014-2018) science program aimed at improving knowledge about the marine environments in the regions around Darwin and Bynoe Harbour’s through the collection and collation of baseline data that will enable the creation of thematic habitat maps to underpin marine resource management decisions. This project is being led by the Northern Territory Government and is supported by the INPEX-led Ichthys LNG Project, in collaboration with - and co-investment from GA and AIMS. The program builds upon an NT Government project (2011-2011) which saw the collection of baseline data (multibeam echosounder data, sediment samples and video transects) from inner Darwin Harbour (Siwabessy et al. 2015). Radke, L., Smit, N., Li, J., Nicholas, T., Picard, K. 2017. Outer Darwin Harbour Shallow Water Sediment Survey 2016: GA0356 – Post-survey report. Record 2017/06. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2017.006 This research was funded by the INPEX-led Ichthys LNG Project via the Northern Territory (NT) Government Department of Land Resource Management (DLRM) (now the Department of Environment and Natural Resources (DENR)), and co-investment from Geoscience Australia (GA) and Australian Institute of Marine Science (AIMS). We are grateful to the following agencies for providing boats and staff, and to the following personal for help with sample acquisition: NT DENR (Danny Low Choy and Rachel Groome), NT Fisheries (Wayne Baldwin, Quentin Allsop, Shane Penny, Chris Errily, Sean Fitzpatrick and Mark Grubert), NT Parks and Wildlife (Ray Chatto, Stewart Weorle, and Luke McLaren) and the Larrakia Rangers (Nelson Tinoco, Kyle Lewfat, Alan Mummery and Steven Dawson). Special thanks to the skippers Danny Low Choy, Wayne Baldwin, Stewart Weorle and Luke McLaren whose seamanship strongly guided the execution of this survey. AIMS generously allowed use of the aquarium and laboratory at the Arafura Timor Sea Research Facility, and Simon Harries and Kirsty McAllister helped with the setup. We would also like to acknowledge and thank GA colleagues including: Matt Carey, Ian Atkinson and Craig Wintle (Engineering and Applied Scientific Services) for the organisation of field supplies and the design of the new core incubation set-up. This dataset is published with the permission of the CEO, Geoscience Australia

  • This report presents the location and sources of sediment samples and observational data in the Vestfold Hills (between 68° 23' and 68° 40' S, 77° 50' and 78° 35' E) to provide physical and chemical properties, sedimentary processes, and glacial and marine history of the terrestrial environment. This compilation of samples and observations incorporates data collected from the 1970s to present from published and unpublished sources. Sample locations and types are presented here to make them more readily available for further analysis and interpretation. Samples and observations are presented as point locations and include sample type, analyses, and references to the original data source.

  • This Surat Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Surat Basin is a sedimentary basin with approximately 2500 m of clastic fluvial, estuarine, coastal plain, and shallow marine sedimentary rocks, including sandstone, siltstone, mudstone, and coal. Deposition occurred over six cycles from the Early Jurassic to the Cretaceous, influenced by eustatic sea-level changes. Each cycle lasted 10 to 20 million years, ending around the mid-Cretaceous. Bounded by the Auburn Arch to the northeast and the New England Orogen to the southeast, it connects to the Clarence-Moreton Basin through the Kumbarilla Ridge. The Central Fold Belt forms its southern edge, while Cenozoic uplift caused erosion in the north. The basin's architecture is influenced by pre-existing faults and folds in the underlying Bowen Basin and the nature of the basement rocks from underlying orogenic complexes. Notable features include the north-trending Mimosa Syncline and Boomi Trough, overlying the deeper Taroom Trough of the Bowen Basin and extending southwards. The Surat Basin overlies older Permian to Triassic sedimentary basins like the Bowen and Gunnedah Basins, unconformably resting on various older basement rock terranes, such as the Lachlan Orogen, New England Orogen, and Thomson Orogen. Several Palaeozoic basement highs mark its boundaries, including the Eulo-Nebine Ridge in the west and the Kumbarilla Ridge in the east. Paleogene to Neogene sediments, like those from the Glendower Formation, cover parts of the Surat Basin. Remnant pediments and Cenozoic palaeovalleys incised into the basin have added complexity to its geological history and may influence aquifer connections. Overall, the Surat Basin's geological history is characterized by millions of years of sedimentation, tectonic activity, and erosion, contributing to its geological diversity and economic significance as a source of natural resources, including coal and natural gas.

  • Poster describing how GA made the WASANT palaeovalley map (GEOCAT #73980).

  • This Bowen Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Bowen Basin is part of the Sydney–Gunnedah–Bowen basin system and contains up to 10,000 m of continental and shallow marine sedimentary rocks, including substantial deposits of black coal. The basin's evolution has been influenced by tectonic processes initiated by the New England Orogen, commencing with a phase of mechanical extension, and later evolving to a back-arc setting associated with a convergent plate margin. Three main phases of basin development have been identified; 1) Early Permian: Characterized by mechanical extension, half-graben development, thick volcanic units and fluvio-lacustrine sediments and coal deposits. 2) Mid Permian: A thermal relaxation event led to the deposition of marine and fluvio-deltaic sediments, ending with a regional unconformity. 3) Late Permian and Triassic: Foreland loading created a foreland basin setting with various depositional environments and sediment types, including included fluvial, marginal marine, deltaic and marine sediments along with some coal deposits in the late Permian, and fluvial and lacustrine sediments in the Triassic. Late Permian peat swamps led to the formation of extensive coal seams dominating the Blackwater Group. In the Triassic, fluvial and lacustrine deposition associated with foreland loading formed the Rewan Formation, Clematis Sandstone Group, and Moolayember Formation. The basin is a significant coal-bearing region with over 100 hydrocarbon accumulations, of which about one third are producing fields. The Surat Basin overlies the southern Bowen Basin and contains varied sedimentary assemblages hosting regional-scale aquifer systems. Cenozoic cover to the Bowen Basin includes a variety of sedimentary and volcanic rock units. Palaeogene and Neogene sediments mainly form discontinuous units across the basin. Three of these units are associated with small eponymous Cenozoic basins (the Duaringa, Emerald and Biloela basins). Unnamed sedimentary cover includes Quaternary alluvium, colluvium, lacustrine and estuarine deposits; Palaeogene-Neogene alluvium, sand plains, and duricrusts. There are also various Cenozoic intraplate volcanics across the Bowen Basin, including central volcanic- and lava-field provinces.

  • This Clarence-Moreton Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The formation of the Clarence-Moreton Basin initiated during the Middle Triassic due to tectonic extension. This was followed by a prolonged period of thermal cooling and relaxation throughout the Late Triassic to the Cretaceous. Deposition of a non-marine sedimentary succession occurred during this time, with the Clarence-Moreton Basin now estimated to contain a sedimentary thickness of up to 4000 m. There were three main depositional centres within the basin, and these are known as the Cecil Plain Sub-basin, Laidley Sub-basin and Logan Sub-basin. The Clarence-Moreton Basin sediments were originally deposited in non-marine environments by predominantly northward flowing rivers in a relatively humid climate. The sedimentary sequences are dominated by a mixed assemblage of sandstone, siltstone, mudstone, conglomerate and coal. Changing environmental conditions due to various tectonic events resulted in deposition of interbedded sequences of fluvial, paludal (swamp) and lacustrine deposits. Within the Clarence-Moreton Basin, coal has been mined primarily from the Jurassic Walloon Coal Measures, including for the existing mines at Commodore and New Acland. However, coal deposits also occur in other units, such as the Grafton Formation, Orara Formation, Bundamba Group, Ipswich Coal Measures, and Nymboida Coal Measures. Overlying the Clarence-Moreton Basin in various locations are Paleogene and Neogene volcanic rocks, such as the Main Range Volcanics and Lamington Volcanics. The thickness of these volcanic rocks is typically several hundred metres, although the maximum thickness of the Main Range Volcanics is about 900 m. Quaternary sediments including alluvial, colluvial and coastal deposits also occur in places above the older rocks of the Clarence-Moreton Basin.

  • This Amadeus Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Amadeus Basin is a sedimentary basin in central Australia that spans from the Neoproterozoic to Late Devonian, potentially Early Carboniferous, periods. It contains clastic, carbonate, and evaporitic sedimentary rocks, with a total thickness of 6,000 m to 14,000 m. The Neoproterozoic section alone is up to 3,000 m thick and is divided into four super-sequences separated by major unconformities. The basin is an active hydrocarbon province, with ongoing oil and gas production and the potential for further discoveries. Several key petroleum source rock units have been identified in the Amadeus Basin. The Gillen Formation, found in the northeast, consists of marine black shale, dolostone, sandstone, and evaporite, reaching a maximum thickness of 850 m. The Loves Creek Formation comprises deep water grainstone and mudstone overlain by stromatolite-bearing grainstone and dolostone, with a thickness of up to 500 m. The Johnnys Creek Formation is a unit composed of red bed and dolomitic limestone or dolostone, along with siltstone and sandstone, up to 400 m thick. The Inindia beds consist of sandstone, siltstone, chert, jasper, tillite, and dolostone, with a maximum thickness of 2,000 m and were deposited in shallow marine conditions. The Aralka Formation is a siltstone and shale unit with two members, the Ringwood Member and the Limbla Member, reaching a thickness of up to 1,000 m. The Pertatataka Formation is a turbiditic red and green siltstone and shale unit, along with minor feldspathic sandstone, deposited in a deep marine or marine shelf environment, typically about 350 m thick but up to 1,400 m thick at certain locations. The Winnall Group is a succession of sandstone and siltstone, with a maximum thickness of 2,134 m. The Chandler Formation is a poorly exposed unit consisting of halite, foetid carbonate mudstone, shale, and siltstone, deposited in a shallow marine environment, with halite deposits reaching thicknesses of 230 m to 450 m. The Giles Creek Dolostone is a carbonate and siltstone unit, with minor sandstone, deposited in a shallow-marine environment. The Horn Valley Siltstone is a thinly bedded shale and siltstone, with nodular limestone and sandy phosphatic and glauconitic interbeds, serving as the primary hydrocarbon source rock in the basin. Lastly, the Stairway Sandstone is 544 m thick and divided into three subunits, consisting of quartzitic sandstone, black shale, siltstone, mudstone, and phosphorites.

  • This Wiso Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Wiso Basin, a large intra-cratonic basin in the central Northern Territory, covers about 140,000 square kilometres and is part of the Centralian Superbasin. It is bounded by the Tennant and Tanami regions to the east and west, while a thrust fault separates it from the Arunta Region to the south. The basin adjoins the Georgina Basin in the southeast and joins the Daly and Georgina basins beneath the Cretaceous strata of the Carpentaria Basin in the north. The basin contains a relatively flat, undeformed succession of strata that gently dip towards the main depo-centre, the Lander Trough. About 80% of the basin consists of shallow middle Cambrian strata, while the remaining portion is within the Lander Trough, containing a diverse succession of Cambrian, Ordovician, and Devonian units. The depositional history and stratigraphy reveal that early Cambrian saw widespread basaltic volcanism, with the Antrim Plateau Volcanics forming the base layer and aquitard of the Wiso Basin. The middle Cambrian deposits include the Montejinni Limestone, the oldest sedimentary unit, followed by the Hooker Creek Formation and the Lothari Hills Sandstone. The uppermost Cambrian unit is the Point Wakefield beds. The Ordovician deposits consist of the Hansen River beds, primarily composed of fossiliferous sandstone and siltstone deposited in shallow marine environments. The Devonian unit capping the basin is the Lake Surprise Sandstone, found in the Lander Trough area, formed in shallow marine, shoreline, and fluvial environments during the Alice Springs Orogeny. Three main hypotheses have been proposed for the formation of the Lander Trough: a large crustal downwarp before thrusting of Paleoproterozoic rocks, the formation of a half-graben by faulting along the southern boundary, or the formation of two en-echelon synclines by vertical block movement. While the majority of the Wiso Basin consists of shallow middle Cambrian rocks, the Lander Trough presents a more varied stratigraphic sequence, holding potential for Neoproterozoic and early Cambrian rocks. However, further drilling is needed to verify this. The presence of similar units in neighbouring basins provides valuable insight into the basin's geological history and development.

  • <div>This document provides metadata for the gross depositional environment (GDE) interpretations that have been generated in support of the energy resource assessments under the Australia’s Future Energy Resources (AFER) project.&nbsp;&nbsp;</div><div>The AFER projects is part of Geoscience Australia’s Exploring for the Future (EFTF) Program—an eight year, $225 million Australian Government funded geoscience data and precompetitive information acquisition program 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 will help support a strong economy, resilient society and sustainable environment for the benefit of all Australians. The EFTF program is supporting Australia’s transition to a low emissions economy, industry and agriculture sectors, as well as economic opportunities and social benefits for Australia’s regional and remote communities. Further details are available at http://www.ga.gov.au/eftf.&nbsp;</div><div>The GDE data sets provide high level classifications of interpreted environments where sediments were deposited within each defined play interval in the Pedirka, Simpson and Western Eromanga basins. Twelve gross depositional environments have been interpreted and mapped in the study (Table 1). A total of 14 play intervals have been defined for the Pedirka, Simpson and Western Eromanga basins by Bradshaw et al. (2022, in press), which represent the main chronostratigraphic units separated by unconformities or flooding surfaces generated during major tectonic or global sea level events (Figure 1). These play intervals define regionally significant reservoirs for hydrocarbon accumulations or CO2 geological storage intervals, and often also include an associated intraformational or regional seal.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</div><div>GDE interpretations are a key data set for play-based resources assessments in helping to constrain reservoir presence. The GDE maps also provide zero edges showing the interpreted maximum extent of each play interval, which is essential information for play-based resource assessments, and for constructing accurate depth and thickness grids.&nbsp;&nbsp;</div><div>GDE interpretations for the AFER Project are based on integrated interpretations of well log and seismic data, together with any supporting palynological data. Some play intervals also have surface exposures within the study area which can provide additional published paleo-environmental data. The Pedirka, Simpson and Western Eromanga basins are underexplored and contain a relatively sparse interpreted data set of 42 wells and 233 seismic lines (Figure 2). Well and outcrop data provide the primary controls on paleo-environment interpretations, while seismic interpretations constrain the interpreted zero edges for each play interval. The sparse nature of seismic and well data in the study area means there is some uncertainty in the extents of the mapped GDE’s.&nbsp;&nbsp;</div><div>The data package includes the following datasets:&nbsp;&nbsp;</div><div>Play interval tops for each of the 42 wells interpreted – provided as an ‘xlsx’ file.&nbsp;</div><div>A point file (AFER_Wells_GDE) capturing the GDE interpretation for each of the 14 play intervals in each of the 42 wells – provided as both a shapefile and within the AFER_GDE_Maps geodatabase.&nbsp;</div><div>Gross depositional environment maps for each of the 14 play intervals (note that separate GDE maps have been generated for the Namur Sandstone and Murta Formation within the Namur-Murta play interval, and for the Adori Sandstone and Westbourne Formation within the Adori-Westbourne play interval) – provided as both shapefiles and within the AFER_GDE_Maps geodatabase.&nbsp;</div><div>&nbsp;</div><div>These GDE data sets are being used to support the AFER Project’s play-based energy resource assessments in the Western Eromanga, Pedirka and Simpson basins.&nbsp;</div><div><br></div>

  • Preamble: The 'National Geochemical Survey of Australia: The Geochemical Atlas of Australia' was published in July 2011 along with a digital copy of the NGSA geochemical dataset (http://dx.doi.org/10.11636/Record.2011.020). The NGSA project is described here: www.ga.gov.au/ngsa. The present dataset contains additional geochemical data obtained on NGSA samples: the Lead Isotopes Dataset. Abstract: Over 1200 new lead (Pb) isotope analyses were obtained on catchment outlet sediment samples from the NGSA regolith archive to document the range and patterns of Pb isotope ratios in the surface regolith and their relationships to geology and anthropogenic activity. The selected samples included 1204 NGSA Top Outlet Sediment (TOS) samples taken from 0 to 10 cm depth and sieved to <2 mm (or ‘coarse’ fraction); three of these were analysed in duplicate for a total of 1207 Pb isotope analyses. Further, 12 Northern Australia Geochemical Survey (NAGS; http://dx.doi.org/10.11636/Record.2019.002) TOS samples from within a single NGSA catchment, also sieved to <2 mm, were analysed to provide an indication of smaller scale variability. Combined, we thus present 1219 new TOS coarse, internally comparable data points, which underpin new national regolith Pb isoscapes. Additionally, 16 NGSA Bottom Outlet Sediment (BOS; ~60 to 80 cm depth) samples, also sieved to <2 mm, and 16 NGSA TOS samples sieved to a finer grainsize (<75 um, or ‘fine’) fraction from selected NGSA catchments were also included to inform on Pb mobility and residence. Lead isotope analyses were performed by Candan Desem as part of her PhD research at the School of Geography, Earth and Atmospheric Sciences, University of Melbourne. After an initial ammonium acetate (AmAc) leach, the samples were digested in aqua regia (AR). Although a small number of samples were analysed after the AmAc leach, all samples were analysed after the second, AR digestion, preparation step. The analyses were performed without prior matrix removal using a Nu Instruments Attom single collector Sector Field-Inductively Coupled Plasma-Mass Spectrometer (SF-ICP-MS). The dried soil digests were redissolved in 2% HNO3 run solutions containing high-purity thallium (1 ppb Tl) and diluted to provide ~1 ppb Pb in solution. Admixture of natural, Pb-free Tl (with a nominal 205Tl/203Tl of 2.3871) allowed for correction of instrumental mass bias effects. Concentrations of matrix elements in the diluted AR digests are estimated to be in the range of 1–2 ppm. The SF-ICP-MS was operated in wet plasma mode using a Glass Expansion cyclonic spray chamber and glass nebuliser with an uptake rate of 0.33 mL/min. The instrument was tuned for maximum sensitivity and provided ~1 million counts per second/ppb Pb while maintaining flat-topped peaks. Each analysis, performed in the Attom’s ‘deflector peak jump’ mode, consists of 30 sets of 2000 sweeps of masses 202Hg, 203Tl, 204Pb, 205Tl, 206Pb, 207Pb and 208Pb, with dwell times of 500 μs and a total analysis time of 4.5 min. Each sample acquisition was preceded by a blank determination. All corrections for baseline, sample Hg interference (202Hg/204Pb ratios were always <0.043) and mass bias were performed online, producing typical in-run precisions (2 standard errors) of ±0.047 for 206Pb/204Pb, ±0.038 for 207Pb/204Pb, ±0.095 for 208Pb/204Pb, ±0.0012 for 207Pb/206Pb and ±0.0026 for 208Pb/206Pb. A small number of samples with low Pb concentrations exhibited very low signal sizes during analysis resulting in correspondingly high analytical uncertainties. Samples producing within-run uncertainties of >1% relative (measured on the 207Pb/204Pb ratio) were discarded as being insufficiently precise to contribute meaningfully to the dataset. Data quality was monitored using interspersed analyses of Tl-doped ~1 ppb solutions of the National Institute of Standards and Technology (NIST) SRM981 Pb standard, and several silicate reference materials: United States Geological Survey ‘BCR-2’ and ‘AGV-2’, Centre de Recherches Pétrographiques et Géochimiques ‘BR’ and Japan Geological Survey ‘JB-2’. In a typical session, up to 50 unknowns plus 15 standards were analysed using an ESI SC-2 DX autosampler. Although previous studies using the Attom SF-ICP-MS used sample-standard-bracketing techniques to correct for instrumental Pb mass bias, Tl doping was found to produce precise, accurate and reproducible results. Based upon the data for the BCR-2 and AGV-2 secondary reference materials, for which we have the most analyses, deviations from accepted values (accuracy) were typically <0.17%. Data for the remaining silicate standards appear slightly less accurate but these results may, to some extent, reflect uncertainty in the assigned literature values for these materials. Replicate runs of selected AR digests yielded similar reproducibility estimates. The results show a wide range of Pb isotope ratios in the NGSA (and NAGS) TOS <2 mm fraction samples across the continent (N = 1219): 206Pb/204Pb: Min = 15.558; Med ± Robust SD = 18.844 ± 0.454; Mean ± SD = 19.047 ± 1.073; Max = 30.635 207Pb/204Pb; Min = 14.358; Med ± Robust SD = 15.687 ± 0.091; Mean ± SD = 15.720 ± 0.221; Max = 18.012 208Pb/204Pb; Min = 33.558; Med ± Robust SD = 38.989 ± 0.586; Mean ± SD = 39.116 ± 1.094; Max = 48.873 207Pb/206Pb; Min = 0.5880; Med ± Robust SD = 0.8318 ± 0.0155; Mean ± SD = 0.8270 ± 0.0314; Max = 0.9847 208Pb/206Pb; Min = 1.4149; Med ± Robust SD = 2.0665 ± 0.0263; Mean ± SD = 2.0568 ± 0.0675; Max = 2.3002 These data allow the construction of the first continental-scale regolith Pb isotope maps (206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb, 207Pb/206Pb, and 208Pb/206Pb isoscapes) of Australia and can be used to understand contributions of Pb from underlying bedrock (including Pb-rich mineralisation), wind-blown dust and possibly from anthropogenic sources (industrial, transport, agriculture, residential, waste handling). The complete dataset is available to download as a comma separated values (CSV) file from Geoscience Australia's website (http://dx.doi.org/10.26186/5ea8f6fd3de64). Isoscape grids (inverse distance weighting interpolated grids with a power coefficient of 2 prepared in QGis using GDAL gridding tool based on nearest neighbours) are also provided for the five Pb isotope ratios (IDW2NN.TIF files in zipped folder). Alternatively, the new Pb isotope data can be downloaded from and viewed on the GA Portal (https://portal.ga.gov.au/).