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  • This Lake Eyre 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 Lake Eyre Basin (LEB) is a vast endorheic basin covering approximately 15% of the Australian continent, spanning about 1.14 million square kilometres. Its development began during the Late Palaeocene due to tectonic subsidence in north-eastern South Australia, resulting in a wide and shallow intra-cratonic basin divided into Tirari and Callabonna Sub-basins by the Birdsville Track Ridge. The depocenter of the LEB has shifted southwards over time. During the Cenozoic era, sediment accumulation was highest near the Queensland-Northern Territory border. The depo-center was in the southern Simpson Desert by the late Neogene, and is currently in Kati Thanda-Lake Eyre, leading to the deposition of various sedimentary formations, which provide a record of climatic and environmental changes from a wetter environment in the Palaeogene to the arid conditions of the present. The LEB is characterized by Cenozoic sediments, including sand dunes and plains in the Simpson, Strezelecki, Tirari, and Strezelecki deserts, mud-rich floodplains of rivers like Cooper, Diamantina, and Georgina, and extensive alluvial deposits in the Bulloo River catchment. The basin's geology comprises rocks from different geological provinces, ranging from Archean Gawler Craton to the Cenozoic Lake Eyre Basin. The Callabonna Sub-basin, confined by the Flinders Ranges to the west, contains formations such as the Eyre and Namba formations, representing fluvial and lacustrine environments. The Cooper Creek Palaeovalley hosts formations like the Glendower, Whitula, Doonbara, and Caldega, and features significant Quaternary sedimentary fill. The Tirari Sub-basin, located on the border regions of three states, contains formations like the Eyre, Etadunna, Mirackina, Mount Sarah Sandstone, Yardinna Claystone, Alberga Limestone, and Simpson Sand. The northwest of Queensland includes smaller Cenozoic basins, likely infilled ancient valleys or remnants of larger basins. The Marion-Noranside Basin has the Marion Formation (fluvial) and Noranside Limestone (lacustrine), while the Austral Downs Basin comprises the Austral Downs Limestone (spring and lacustrine). The Springvale and Old Cork Basins tentatively have Eocene and Miocene ages. Cenozoic palaeovalleys in the Northern Territory are filled with fluvial sands, gravels, lignites, and carbonaceous deposits and are confined by surrounding basins. Overall, the sedimentary sequences in the Lake Eyre Basin provide valuable insights into its geological history, climate shifts, and topographic changes, contributing to our understanding of the region's development over time.

  • Many scientific talks by Geoscience Australia staff are published on YouTube. These documents provide summaries (‘crib sheets’) of the presentations along with easy access links to each part of the video. They are intended to help teachers of Year 11/12 classes learning about natural hazards

  • This Sydney 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 Sydney Basin, part of the Sydney–Gunnedah–Bowen basin system, consists of rocks dating from the Late Carboniferous to Middle Triassic periods. The basin's formation began with extensional rifting during the Late Carboniferous and Early Permian, leading to the creation of north-oriented half-grabens along Australia's eastern coast. A period of thermal relaxation in the mid Permian caused subsidence in the Bowen–Gunnedah–Sydney basin system, followed by thrusting of the New England Orogen from the Late Permian through the Triassic, forming a foreland basin. Deposition in the basin occurred in shallow marine, alluvial, and deltaic environments, resulting in a stratigraphic succession with syn-depositional folds and faults, mostly trending north to north-east. The Lapstone Monocline and Kurrajong Fault separate the Blue Mountains in the west from the Cumberland Plain in the central part of the basin. The Sydney Basin contains widespread coal deposits classified into geographic coalfield areas, including the Southern, Central, Western, Newcastle, and Hunter coalfields. These coalfields are primarily hosted within late Permian strata consisting of interbedded sandstone, coal, siltstone, and claystone units. The coal-bearing formations are grouped based on sub-basins, namely the Illawarra, Tomago, Newcastle, and Wittingham coal measures, underlain by volcanic and marine sedimentary rocks. Deposition within the basin ceased during the Triassic, and post-depositional igneous intrusions (commonly of Jurassic age) formed sills and laccoliths in various parts of the basin. The maximum burial depths for the basin's strata occurred during the early Cretaceous, reaching around 2,000 to 3,000 metres. Subsequent tectonic activity associated with the Tasman Rift extension in the Late Cretaceous and compressional events associated with the convergence between Australia and Indonesia in the Neogene led to uplift and erosion across the basin. These processes have allowed modern depositional environments to create small overlying sedimentary basins within major river valleys and estuaries, along the coast and offshore, and in several topographic depressions such as the Penrith, Fairfield and Botany basins in the area of the Cumberland Plain.

  • This Central Australian Cenozoic Basins 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. Cenozoic basins are an important source of readily accessible groundwater within the arid deserts of central Australia. This province represents a collection of six notable Cenozoic basins within the region, including the Ti Tree, Waite, Hale, Mount Wedge, Lake Lewis and Alice Farm basins. Many local communities in this region (such as Papunya, Ti Tree and Ali Curung) rely upon groundwater stored within Cenozoic basin aquifers for their water security. The basins typically contain up to several hundred metres of saturated sediments that can include relatively thick intervals of hydraulically conductive sands, silts and minor gravels. It is noted that the potential groundwater storage volumes in the Cenozoic basins are much greater than the annual amount of runoff and recharge that occurs in central Australia, making them prospective targets for groundwater development. Groundwater quality and yields are variable, although relatively good quality groundwater can be obtained at suitable yields in many areas for community water supplies, stock and domestic use and irrigated horticulture operations, for example, in the Ti Tree Basin. However, not all of the Cenozoic basins have the potential to supply good quality groundwater resources for community and horticultural supplies. With the exception of several small sub-regions, most of the Waite Basin has very little potential to supply good quality groundwater for agricultural use. This is mainly due to limited aquifer development, low yielding bores and elevated groundwater salinity (commonly >2000 mg/L Total Dissolved Solids). However, bores have been successfully installed for smaller-scale pastoral stock and domestic supplies and small communities or outstations in the Waite Basin.

  • This Gippsland 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 Gippsland Basin is an asymmetrical east-trending rift structure that originated during rifting in the Late Jurassic to Early Cretaceous, as Australia and Antarctica began to separate. Over time, it developed into a continental passive margin basin, with sedimentation continuing to the present day. The basin is characterized by four main phases of tectonic evolution, interspersed with eustatic sea-level variations: initial rifting and extension, mid-Cretaceous contraction, renewed extension, and cessation of rifting in the middle Eocene. The basin's geological structures consist of mainly east to north-east trending features, with the west dominated by north-east structures due to the influence of basement trends. Major fault systems are prominent, compartmentalizing the basin into platforms and depressions separated by bedrock highs. The basin's complex stratigraphic succession reveals fluvial, deltaic, marginal marine, and open marine depositional environments. The sedimentary sequence includes terrigenous siliciclastic sediments from the Upper Cretaceous to Eocene, followed by post-rift sands, clays, coals, and limestones/marls of Oligocene to Holocene age. The Gippsland Basin's sediments are subdivided into four main stratigraphic groups: the Strzelecki, Latrobe, Seaspray, and Sale groups. The Strzelecki Group, dating from the Late Jurassic to Early Cretaceous, consists of non-marine sedimentary rocks deposited in fluvial and lacustrine environments. The Latrobe Group, from Late Cretaceous to early Oligocene, contains siliciclastic sediments deposited in various non-marine to marginal marine settings, showing significant lateral lithofacies variations. The Seaspray Group, dating from Oligocene to Pliocene, formed during a post-rift phase, characterized by marine limestone and marl units and continental clastic sediments. Lastly, the Sale Group consists of Miocene-to-Recent continental clastic sediments forming a thin veneer over the onshore portion of the basin. The Gippsland Basin also contains several basaltic lava fields, with two notable volcanic units—the Thorpdale Volcanics and Carrajung Volcanics—part of the Older Volcanics in Victoria. Overall, the Gippsland Basin's geological history and diverse sedimentary deposits make it a significant area for various geological and geophysical studies, including its hydrocarbon resources concentrated in offshore Latrobe Group reservoirs.

  • This Port Phillip-Westernport 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 Port Phillip and Westernport basins are small, shallow sedimentary basins located in south-central Victoria, formed during the Late Cretaceous rifting of Australia and Antarctica. They share similar stratigraphy with nearby basins. The Port Phillip Basin is bounded by the Selwyn and Rowsley Faults to the east and west, while the Heath Hill Fault marks the eastern boundary of the Westernport Basin. Both basins have pre-Cenozoic basement rocks comprising folded and faulted Paleozoic metasedimentary rocks and granites from the Lachlan Fold Belt. The Port Phillip Basin's stratigraphy includes Maastrichtian to Cenozoic sedimentary units with intercalated volcanic rocks. The main depocentres are the Sorrento Graben, Ballan Graben/Lal Lal Trough, and Parwan Trough. Notable formations are the Yaloak and Werribee formations, with coal-bearing strata and marine sediments. The Westernport Basin has coastal sediments and volcanic deposits from Paleocene to Holocene. It experienced marine transgressions and regressions due to sea-level fluctuations. Fault movements in the late Pliocene and early Pleistocene formed a fault-bounded depression centered on the Koo Wee Rup Plain. The main units are the Childers Formation, Older Volcanics, Yallock Formation, Sherwood Marl, and Baxter Sandstone. Both basins have Quaternary sediments, including Pleistocene eolian sand sequences, Holocene alluvial and paludal clays, and fluvial sediments in valleys and palaeovalleys. The Port Phillip Basin contains distinct phases of terrestrial and marine deposition, while the Westernport Basin has Eocene volcanism and marine sediments. These basins are important geological features in the region, with various formations representing millions of years of geological history.

  • This Tasmania 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 Late Carboniferous to Late Triassic Tasmania Basin covers approximately 30,000 square kilometres of onshore Tasmania. The basin contains up to 1500 m of mostly flat-lying sedimentary rocks, and these are divided into two distinct lithostratigraphic units, the Lower and the Upper Parmeener Supergroup. The Lower Parmeener Supergroup comprises Late Carboniferous to Permian rocks that mainly formed in marine environments. The most common rock types in this unit are mudstone, siltstone and sandstone, with less common limestone, conglomerate, coal, oil shale and tillite. The Upper Parmeener Supergroup consists predominantly of non-marine rocks, typically formed in fluvial and lacustrine environments. Common rock types include sandstone, siltstone, mudstone and minor basalt layers. Post-deposition the rocks of the Parmeener Supergroup experienced several major geological events, including the widespread intrusion of tholeiitic dolerite magma during the Middle Jurassic.

  • This animation shows how Magnetotelluric (MT) Surveys Work. It is part of a series of Field Activity Technique Engagement Animations. The target audience are the communities that are impacted by our data acquisition activities. There is no sound or voice over. The 2D animation includes a simplified view of what magnetotelluric (MT) stations and equipment looks like what the equipment measures and how the survey works.

  • As part of the Great Artesian Basin (GAB) Project a pilot study was conducted in the northern Surat Basin, Queensland, to test the ability of existing and new geoscientific data and technologies to further improve our understanding of hydrogeological systems within the GAB, in order to support responsible management of basin water resources. This report presents selected examples from the preliminary interpretation of modelled airborne electromagnetic (AEM) data acquired as part of this pilot study. The examples are selected to highlight key observations from the AEM with potential relevance to groundwater recharge and connectivity. Previous investigations in the northern Surat Basin have suggested that diffuse groundwater recharge rates are generally low (in the order of only a few millimetres per year) across large areas of the GAB intake beds—outcropping geological units which represent a pathway for rainfall to enter the aquifers—and that, within key aquifer units, recharge rates and volumes can be heterogeneous. Spatial variability in AEM conductivity responses is identified across different parts of the northern Surat Basin, including within the key Hutton Sandstone aquifer. Consistent with findings from other studies, this variability is interpreted as potential lithological heterogeneity, which may contribute to reduced volumes of groundwater entering the deeper aquifer. The influence of geological structure on aquifer geometry is also examined. Larger structural zones are seen to influence both pre- and post-depositional architecture, including the presence, thickness and dip of hydrogeological units (or parts thereof). Folds and faults within the Surat Basin sequences are, in places, seen as potential groundwater divides which may contribute to compartmentalisation of aquifers. Discrete faults have the potential to influence inter-aquifer connectivity. The examples presented here demonstrate the utility of AEM models, in conjunction with other appropriate geophysical and geological data, for characterising potential recharge areas and pathways within the main GAB aquifer units, by helping to better define aquifer geometry, lithological heterogeneity and possible structural controls. Such assessments have the potential to further improve our understanding of groundwater recharge and flow path variability at local to regional scales. Acquisition of broader AEM data coverage across groundwater recharge areas, along with complementary geophysical, geological and hydrogeological data, would further assist in quantifying recharge variability, facilitating revised water balance estimates for the basin and thereby supporting GAB water resource management and policy decision-making.

  • This report presents geoscientific advice for the management of Antarctic Specially Protected Area (ASPA) No. 143, Marine Plain in the Vestfold Hills, East Antarctica. The advice is based on expert field observations and Remotely Piloted Aircraft (RPA) imagery of the ASPA as well as a review of observations and reports from previous visitors and scientific literature on human disturbance in polar environments. This report builds on an earlier report (McLennan 2017) which was written prior to any site visits by Geoscience Australia scientists. The advice addresses questions raised by the Australian Antarctic Division regarding the ASPA management plan, particularly relating to access via foot and helicopter, and the condition of two fossil sites. Key assumptions include that the rate of visitors to Marine Plain in the next decade will remain low and that the remaining faunal fossil specimens will stay in place. If there is a large increase in visitor numbers to Marine Plain or the fossil fauna are intended to be removed, further advice should be sought about the impacts to Marine Plain values.