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

This Georgina 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 Georgina Basin is a large intra-cratonic sedimentary basin in central Australia that has undergone several deformation events throughout its geological history. Its deposition began during the Neoproterozoic due to the breakup and erosion of the Rodinia Supercontinent, resulting in the broader Centralian Superbasin, encompassing the Amadeus, Georgina, Ngalia, Officer, and Savory basins. The basin's initial formation occurred as a north-west trending extensional structure in its southern part, containing thick sequences preserved in structural depo-centres such as the Toko Syncline, Dulcie Syncline, and Burke River Structural Zone. The basin unconformably overlies Proterozoic basement rocks, with its eastern boundary onlapping the Mesoproterozoic Mount Isa Province. The Georgina Basin is connected to the Daly and Wiso basins by early to middle Cambrian seaways in some areas, while in others, they are separated by basement highs like the Tomkinson, Warramunga, and Davenport provinces. The northern Georgina Basin is overlain by Mesozoic rocks of the Carpentaria Basin, and the southern basin is covered by Cenozoic deposits. The stratigraphy and rock types within the Georgina Basin include Neoproterozoic rock units in the southern parts correlated with the Centralian Superbasin, characterized by dolostone, tillite, sandstone, quartzite, siltstone, conglomerate, and shale. The basin's structure has been moderately deformed by folding and faulting, with the most significant deformation in its southern part related to the Ordovician to Carboniferous Alice Springs Orogeny. The basin's development occurred in several stages, including Neoproterozoic rifting and subsidence, tectonic activity during the Petermann Orogeny, Early Cambrian rifting, Middle to late Cambrian foreland loading and deposition, Early Ordovician minor rifting, transpression during the Alice Springs Orogeny, and a final phase of synorogenic siliclastic sedimentation in a foreland basin setting, is limited to southern depo-centres. Overall, the Georgina Basin's complex geological history has resulted in a diverse array of sedimentary rocks and structural features, making it a significant area of interest for geological studies and resource exploration in central Australia.

This Murray 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 Murray Basin, a significant sedimentary basin in Australia, displays varying sediment thickness across its expanse, with the thickest layers concentrated in its central regions. The basin's geological evolution is characterised by distinct depositional phases. During the Paleocene to Eocene Renmark Group phase, sedimentary deposits encompass fluvial sands at the base, transitioning into paralic carbonaceous clay and lignite layers. These sediments indicate the shift from riverine to shallow marine environments, dating back to the Paleocene and Eocene periods. The Oligocene to Middle Miocene period encompasses the Ettrick Formation and Murray Group Limestone. The former includes marl, and the latter displays glauconitic grey-green marl and bryozoal limestone, revealing prevailing marine conditions during the Oligocene to Middle Miocene. In the Late Miocene to Early Pliocene Bookpurnong Formation, marine shelly dark grey clay and silt, previously known as the Bookpurnong Beds, coexist with Pliocene fluvial to marginal marine quartz sands (Loxton Sands), marking the transition back to terrestrial and nearshore marine settings. During the Late Pliocene to Pleistocene, the Blanchetown Clay, a substantial unit within Lake Bungunnia, signifies lacustrine phases. Overlying ferricretes in the central/eastern basin and the Norwest Bend Formation's oyster coquinas in the western region, the clay exhibits variable coloration and laminations. Lastly, the Pleistocene to Holocene phase witnesses river-induced reworking and erosion of underlying sediments, giving rise to the Shepparton and Coonambidgal formations. In the western Murray Basin, Cenozoic sedimentary rocks are relatively thin, typically measuring under 200-300 meters. The Renmark Trough area presents a maximum thickness of 600 meters.

This Ngalia 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 Ngalia Basin is an elongate, east-trending basin over 500 km long and 90 km wide. It occurs mostly in the Northern Territory, with limited occurrence in Western Australia. The Ngalia Basin is an intra-cratonic sedimentary basin in a structural downwarp formed by a faulted asymmetrical syncline. The basin began to form about 850 Ma, and contains a Neoproterozoic to Carboniferous sedimentary succession. Sedimentation ceased in response to the 450 to 300 Ma Alice Springs Orogeny. The maximum stratigraphic thickness of the Ngalia Basin is about 5000 m. The basin contains mainly arenaceous sedimentary rocks, with lesser fine-grained rock types and some carbonates. Fining upwards sedimentary cycles are commonly preserved and capped by calcite-cemented fine-grained sandstone and siltstone. Tectonic events disrupted deposition during basin evolution and led to at least ten unconformities. There are many disconformable contacts, with angular unconformities common in areas with abundant faulting. The upper-most arkosic sandstone formations in the Ngalia Basin are the Mount Eclipse Sandstone and the Kerridy Sandstone. These units have an aggregate thickness of several hundreds of metres and are the main aquifers within the Ngalia Basin sequence. There is some interstitial porosity, especially in the Mount Eclipse Sandstone, although joints and fissures associated with faulting provide significant secondary permeability. These aquifers provide good supplies of potable to brackish groundwater, and supply the community borefield at Yuendumu. The Ngalia Basin is almost entirely concealed by Cenozoic cover, including Palaeogene-Neogene palaeovalley, lake and alluvial fan sediment systems and Quaternary aeolian sands. Shallow aquifers with brackish to potable water occur in many palaeovalleys sediments overlying the basin.

This Canning 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 Canning Basin, characterized by mostly Paleozoic sedimentary rocks with a maximum thickness of over 15,000 m, went through four major depositional phases from Early Ordovician to Early Cretaceous. The basin contains two main depocenters, the Fitzroy Trough-Gregory Sub-basin in the north and the Willara Sub-basin-Kidson Sub-basin in the south. The depositional history includes marine, evaporite, fluvial, deltaic, glacial, and non-marine environments. The basin's evolution began with extension and rapid subsidence in the Early Ordovician, followed by a sag stage with evaporite and playa conditions in the Late Ordovician and Silurian. The Devonian to Early Carboniferous phase involved marine, reef, fluvio-deltaic, and terrestrial sedimentation in the north and marginal marine to terrestrial systems in the south. The Late Carboniferous to mid-Triassic period saw non-marine and marine settings, including glacial environments. The basin then experienced mid-Jurassic to Early Cretaceous deposition, mainly in deltaic and non-marine environments. Throughout its history, the Canning Basin encountered multiple tectonic phases, including extension, compression, inversion, and wrench movements, leading to various depositional settings and sediment types. Around 250 petroleum wells have been drilled in the basin, with production mainly from Permo-Carboniferous sandstones and Devonian carbonates. Several proven and untested plays, such as draped bioherms, anticlinal closures, and fault blocks, provide potential for hydrocarbon exploration. Late Carboniferous and Jurassic mafic sills intersected in wells indicate additional geological complexity. Additionally, some areas of the Canning Basin are considered suitable for CO2 storage.

This Eromanga 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 Eromanga Basin, part of the Great Artesian Basin (GAB) in Australia, is an extensive Mesozoic sedimentary basin filled with a mix of non-marine and marine rocks. The GAB covers about 22% of the Australian land surface, including areas in Queensland, New South Wales, South Australia, and the Northern Territory. The Eromanga Basin is the largest among the basins that form the GAB. Spanning over 1,250,000 square kilometres in central and eastern Australia, the Eromanga Basin contains rocks ranging from Jurassic to Cretaceous in age. The sedimentary deposits consist of three main basin successions: Early Jurassic to Early Cretaceous fluvial and lacustrine, Early to mid-Cretaceous marine, and Late Cretaceous fluvial-lacustrine successions. The basin's stratigraphic architecture results from a complex interplay between subsidence-controlled accommodation, sediment supply rates, and changing sediment provenance. These controls were influenced by various factors, such as intra-plate stress fields, eustatic sea-level fluctuations, and dynamic mantle-driven topography during the breakup of the Gondwana supercontinent. During the Jurassic and Early Cretaceous, regional uplift of the Australian continent led to an influx of fluvial sand-rich sediments in the western Eromanga Basin. Subsequent rapid subsidence and global high sea levels during the Early Cretaceous allowed marine sediments to spread across much of Australia, including the Eromanga Basin. The basin later returned to non-marine sedimentation during the Late Cretaceous with deposition of the Winton Formation, followed by closure due to an east-directed Late Cretaceous compressional event. This rapid deposition of the Late Cretaceous Winton Formation played a crucial role in generating and expelling hydrocarbons from various source intervals. The movement of the Australian continent significantly impacted the basin, causing most tectonic activity to occur on the southern side of a prominent keel near Innamincka in the southern half of the GAB. Additionally, variations in the mechanical properties of the sub-lithospheric mantle affected stress distribution, leading to changes in surface elevation and the expression of discharge from aquifers, potentially influencing the location and pattern of spring sites within the South Australian part of the GAB.

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.

This Southern Australian Fractured Rock Province 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. Crustal elements are crustal-scale geological regions primarily based on composite geophysical domains, each of which shows a distinctive pattern of magnetic and gravity anomalies. These elements generally relate to the basement, rather than the sedimentary basins. The South Australian Element comprises the Archean-Mesoproterozoic Gawler Craton and Paleo-Mesoproterozoic Curnamona Province, formed over billions of years through sedimentation, volcanism, magmatism, and metamorphism. The region experienced multiple continental-continent collisions, leading to the formation and breakup of supercontinents like Nuna and Rodinia, along with periods of extensional tectonism. Around 1,400 Ma, both the Gawler Craton and Curnamona Province were cratonised, and during the building of the Rodinia supercontinent (1,300-700 Ma), the present configuration of the region emerged. The area between the Gawler and Curnamona provinces contains Neoproterozoic to Holocene cover, including the Adelaide Superbasin, with the Barossa Complex as its basement, believed to be part of the Kimban Orogen. The breakup of Rodinia in the Neoproterozoic (830-600 Ma) resulted in mafic volcanism and extensional episodes, leading to the formation of the Adelaide Superbasin, characterized by marine rift and sag basins flanking the Gawler Craton and Curnamona Province. During the Mesozoic and Cenozoic, some tectonic structures were rejuvenated, while sedimentary cover obscured much of the now flatter terrain. Metamorphic facies in the region vary, with the Gawler and Curnamona provinces reaching granulite facies, while the Adelaide Superbasin achieved the amphibolite facies. The Gawler Craton contains rocks dating back to approximately 3,150 Ma, while the Curnamona Province contains rocks from 1,720 to 1,550 Ma. These ancient regions have undergone various deformation and metamorphic events but have remained relatively stable since around 1,450 Ma. The Adelaide Superbasin is a large sedimentary system formed during the Neoproterozoic to Cambrian, with distinct provinces. It started as an intracontinental rift system resulting from the breakup of Rodinia and transitioned into a passive margin basin in the southeast and a failed rift in the north. Later uplift and re-instigated rifting led to the deposition of thick Cambrian sediments overlying the Neoproterozoic rocks. Overlying basins include late Palaeozoic to Cenozoic formations, such as the Eromanga Basin and Lake Eyre Basin, which are not part of the assessment region but are adjacent to it.

This South-east Australian Fractured Rock Province 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. Groundwater in Australia's fractured rock aquifers is stored in fractures, joints, bedding planes, and cavities within the rock mass, comprising about 40% of the country's groundwater. Much of this water can be utilized for irrigation, town water supplies, stock watering, and domestic use, based on state regulations. Fractured systems account for approximately 33% of all bores in Australia but contribute to only 10% of total extraction due to variable groundwater yield. Quantifying groundwater movement in fractured rock systems is challenging, as it depends on the distribution of major fractures. Groundwater flow direction is more influenced by the orientation of fractures than hydraulic head distribution. Recharge in fractured rock aquifers is typically localized and intermediate. In Eastern Australia, New South Wales' Lachlan Orogen, which extends from central and eastern New South Wales to Victoria and Tasmania, is a significant region with diverse lithological units, including deep marine turbidites, shallow marine to sub-areal sediments, extensive granite bodies, and volcano-intrusive complexes. This region contains various mineral deposits, such as orogenic gold, volcanic-hosted massive sulphide, sediment-hosted Cu-Au, porphyry Au-Cu, and granite-related Sn. Note: The study does not include additional Orogens in the east (New England) and west (Thomson and Delamerian). The Delamerian Orogen is present throughout western Tasmania.

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 (doi: 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 Plutonium Isotopes Dataset. Abstract -- Seventy three fine-fraction (<75 um) Top Outlet Sediment (TOS, 0 – 10 cm depth) NGSA samples from Queensland were analysed for the plutonium (Pu) isotopes 238Pu and 239+240Pu (unresolved 239Pu and 240Pu) to determine: (1) if Pu is detectable in the Australian environment; and (2) what the levels and ranges of Pu retention in selected Queensland catchment soils are. Radiochemical analyses were performed by alpha spectrometry at the radioanalytical laboratories of Radiation and Nuclear Sciences, Department of Health, Queensland, and at the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), Victoria. The method yielded a 239+240Pu trace-level detection limit of 0.04 mBq/g (equivalent to 10.4 fg/kg or 0.0056 net counts per minute) with a relative standard deviation (RSD) of 15.1%. The average tracer recovery was 69% (RSD 25%) over a 3-day count. Total analytical uncertainty ranged from 19% to 90% at close to detection limits. Field duplicate repeatability for 239+240Pu activity concentration ranged from 18% to 45%, which in part at least reflects the inherent heterogeneity of soil/sediments containing refractory particles exhibiting variation in Pu activity concentrations. Analytical duplicate repeatability for 239+240Pu activity concentration ranged from 10% to 23%, with the mean activity concentration and error of the replicates reported with propagation of errors. The results show a wide range of 239+240Pu activity concentration in the fine TOS NGSA samples across Queensland (N = 73): 239+240Pu: Min = <0.04 mBq/g; Med ± MAD (median absolute deviation) = 0.09 ± 0.07 mBq/g; Mean ± SD = 0.29 ± 0.72 mBq/g; 95th percentile = 1.53 mBq/g; Max = 4.88 mBq/g. In comparison the world average background is estimated at 0.2 mBq/g. Analytical results for 39% of samples were below detection. Six samples with 239+240Pu > 0.18 mBq/g (70th percentile) were also analysed for 238Pu by the same alpha spectrometry method. Results ranged from 0.04 to 0.1 mBq/g (N = 6). The complete dataset is available to download as a comma separated values (CSV) file from Geoscience Australia's website (https://pid.geoscience.gov.au/dataset/ga/144101).