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  • One page article discussing aspects of Australian stratigraphy; this article discusses new unit definitions, ne regional publications and changes to the membership of the Australian Stratigraphy Commission.

  • This report was compiled and written to summarise the four-year Palaeovalley Groundwater Project which was led by Geoscience Australia from 2008 to 2012. This project was funded by the National Water Commission's Raising National Water Standards Program, and was supported through collaboration with jurisdictional governments in Western Australia, South Australia and the Northern Territory. The summary report was published under the National Water Commission's 'Waterlines' series. This document is supported by related publications such as the palaeovalley groundwater literature review, the WASANT Palaeovalley Map and associated datasets, and four stand-alone GA Records that outline the detailed work undertaken at several palaeovalley demonstration sites in WA, SA and the NT. Palaeovalley aquifers are relied upon in outback Australia by many groundwater users and help underpin the economic, social and environmental fabric of this vast region. ‘Water for Australia’s arid zone – Identifying and assessing Australia’s palaeovalley groundwater resources’ (the Palaeovalley Groundwater Project) investigated palaeovalleys across arid and semi-arid parts of Western Australia (WA), South Australia (SA) and the Northern Territory (NT). The project aimed to (a) generate new information about palaeovalley aquifers, (b) improve our understanding of palaeovalley groundwater resources, and (c) evaluate methods available to identify and assess these systems.

  • 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.

  • This Karumba 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 Karumba Basin is a shallow geological basin in Queensland, Australia, composed of sedimentary rocks and unconsolidated sediments that cover the Mesozoic Carpentaria Basin. Deposition started during the Late Cretaceous to Early Paleocene and has continued into the Holocene. The basin extends from western Cape York Peninsula into the Gulf of Carpentaria, where it connects with Cenozoic sediment deposits in Papua New Guinea. Although the sediments in both areas share lithostratigraphic and biostratigraphic similarities, their tectonic histories differ. The basin's structural geology is relatively uniform, with a significant downwarp known as the Gilbert-Mitchell Trough in Cape York Peninsula and another depocenter offshore in the Gulf of Carpentaria. The depositional history and stratigraphy of the Karumba Basin can be divided into three cycles of deposition, erosion, weathering, and the formation of stratigraphic units. The earliest cycle (the Bulimba Cycle) began in the Late Cretaceous to Early Paleocene, with episodes of significant uplift along the eastern margins of the basin. This resulted in the deposition of the Bulimba Formation and the Weipa Beds, primarily consisting of claystone, sandstone, conglomerate, and siltstone with minor coal layers. This cycle was followed by a period of planation and deep weathering, creating the Aurukun Surface. The second cycle (the Wyaaba Cycle) was initiated by large-scale earth movements along the Great Dividing Ranges, forming much of the eastern boundary of the Karumba Basin, and leading to the formation of the Wyaaba beds and other equivalent units. These beds consist mainly of fluvial to paralic clay-rich sandstone, conglomerate, siltstone, and claystone. In the south-west, Oligocene to Pliocene limestone deposits also formed in lacustrine settings, and were sourced from and deposited upon the underlying Georgina Basin. The cycle ended with ensuing periods of erosion and weathering and the development of the Pliocene Kendall Surface, as well as widespread basaltic volcanism. The final cycle (the Claraville Cycle) started in the Pliocene and continues to the present. It has experienced several episodes of uplift and deposition controlled by sea level change, climate variability and volcanism in the south. The Claraville beds are unconsolidated sediments, chiefly comprised of clayey quartzose sand and mud with minor gravels, reaching approximately 148 m thickness offshore, and approximately 70 m onshore. As this cycle is still ongoing, no terminal surface has been formed, and most units consist of unconsolidated surficial sediments.

  • This Eucla 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 Eucla Basin, located along Australia's southern margin, covers an extensive area of approximately 1,150,000 square kilometres, housing the world's largest grouping of onshore Cenozoic marine sediments. It stretches over 2000 km from east to west and has four main subdivisions: Scaddan Embayment, Esperance Shelf, Nullarbor Shelf, and Yalata Sub-basin offshore. The basin extends about 350 km inland from the modern southern Australian coastline and terminates around 200 km offshore where it meets sediments of the Australian-Antarctic Basin. The sedimentary succession is largely consistent throughout the entire basin. In the west, it overlaps with the Yilgarn Craton and Albany-Fraser Orogen, while in the east, the Gawler Craton and Officer Basin separate it from the Musgrave Province. The basin contains mainly Cenozoic sediments, with thicker sequences in the east due to sediment movement and regional elevation differences. The onshore Eucla Basin hosts an unfaulted sheet of sediment deposited over a south-sloping shelf during several marine transgressions. The basal units rest on a prominent unconformity above the Bight Basin, indicating a break in deposition during the separation of Australia and Antarctica. The sedimentary sequence comprises various units such as the Hampton Sandstone, Pidinga Formation, and Werillup Formation, followed by the Wilson Bluff Limestone, Abrakurrie Limestone, Nullarbor Limestone, and Roe Calcarenite. The basin's geological history is marked by significant events such as marine transgressions during the Eocene, leading to the deposition of extensive limestone formations. The Miocene saw slight tilting of the basin, exposing the Nullarbor Plain to the atmosphere and limiting further sediment deposition. During the late Miocene to Pliocene, barrier and lagoonal transgressions contributed to the formation of the Roe Calcarenite. The Pliocene period witnessed intense karstification and the development of ferricrete and silcrete, resulting in the unique modern-day topography of the region.

  • Discussion of the uses made of the Australian Stratigraphic units database (ASUD), the sources of data to update it, and issues with maintaining quality. The importance of correct and consistent terminology, and the value of good reviews and editing are highlighted with examples.

  • The Browse Basin, NW Australia, contains significant hydrocarbon reserves. It was identified as potentially suitable for offshore geological storage of CO2. A sequence stratigraphic analysis of 60 key wells was conducted to improve the understanding of sequence architecture, facies and palaeogeographic evolution of the earliest Campanian to latest Maastrichtian section for CO2 storage assessment.in the Browse Basin. This study provided new insights into sediment source and transport to the basin deep. Well log analysis and seismic interpretation identified submarine fans of the K60 interval as potential CO2 storage targets. In some areas potential lateral connection between submarine fans and the shelf via submarine canyons and channels can limit containment. More detailed investigations at a prospect scale are needed to fully assess sand-body connectivity and CO2 storage potential.

  • Discussion of available stratigraphic resources: the Australian Stratigraphic Units Database (ASUD); documentation of procedures for modifying existing units or establishing new ones; contact details for the Australian Stratigraphy Commission members and ASUD staff. Suggestions on ways of raising awareness through modern media such as a podcast or app, and a request for feedback on what sort of approach might appeal to a university student audience.

  • This Perth 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 Perth Basin is a complex geological region extending along Australia's southwest margin for about 1,300 km. It comprises sub-basins, troughs, terraces, and shelves, hosting sedimentary rocks with coal, oil, gas, and significant groundwater resources. Off the coast of Western Australia, it reaches depths of up to 4,500 m, while its onshore part extends up to 90 km inland. The basin is bounded by the Yilgarn Craton to the east, and the Carnarvon and Bremer basins to the north and south. The basin's history involves two main rifting phases in the Permian and Late Jurassic to Early Cretaceous, creating 15 sub-basins with varying sedimentary thickness due to compartmentalization and fault reactivation. The sedimentary succession mainly comprises fluviatile Permian to Early Cretaceous rocks over Archean and Proterozoic basement blocks. Differences exist between northern and southern sequences, with the south being continental and the north featuring marine deposits. During the Permian, faulting and clastic sedimentation dominated, with marine transgressions in the north and continental rocks in the south. The Triassic saw a similar pattern, with the southern succession being continental and the northern succession showing marine deposits. The Kockatea Shale became a primary hydrocarbon source. The Jurassic period witnessed marine incursions in the central basin, while the Late Jurassic experienced sea level regression and deposition of the Yarragadee Formation. The Cretaceous saw the formation of the Early Cretaceous Parmelia Group due to heavy tectonic activity. The southern basin had a marine transgression leading to the Warnbro Group's deposition with valuable groundwater resources. Post-Cretaceous, Cenozoic deposits covered the basin with varying thicknesses. Overall, the Perth Basin's geological history reveals a diverse sedimentary record with economic and resource significance.

  • Exploring for the Future (EFTF) is an Australian Government program led by Geoscience Australia, in partnership with state and Northern Territory governments. The first phase of the EFTF program (2016-2020) aimed to drive industry investment in resource exploration in frontier regions of northern Australia by providing new precompetitive data and information about their energy, mineral and groundwater resource potential. One of the key discoveries of the first phase of the Exploring for the Future program was the identification of a large sedimentary depocentre in the South Nicholson region, an underexplored area straddling north-eastern Northern Territory and north-western Queensland. This depocentre, up to 8 km deep, was termed the ‘Carrara Sub-basin’ by Geoscience Australia. It is interpreted to contain thick sequences of Proterozoic rocks, broadly equivalent to rocks of the greater McArthur Basin (Northern Territory) and northern Lawn Hill Platform and Mount Isa Province (Queensland), known to be highly prospective for sediment-hosted base metals and unconventional hydrocarbons. In order to gain insights into the resource potential of the Carrara Sub-basin, the South Nicholson National Drilling Initiative (NDI) Carrara 1 stratigraphic drillhole was completed in late 2020, as a collaboration between Geoscience Australia, the Northern Territory Geological Survey (NTGS) and the MinEx CRC . NDI Carrara 1 is the first drillhole to intersect the, as yet, undifferentiated Proterozoic rocks of the Carrara Sub-Basin. NDI Carrara 1 is located on the western flanks of the Carrara Sub-basin on the South Nicholson Seismic line (17GA-SN1), reaching a total depth of 1751 mGL, intersecting ca. 630 m of Cambrian Georgina Basin overlying ca. 1100 m of Proterozoic carbonates, black shales and minor siliciclastics . Geoscience Australia is undertaking a range of investigations on the lithology, stratigraphy and geotechnical properties of NDI Carrara 1 based on wireline data, as well as undertaking a range of analyses of over 400 physical samples recovered through the entire core. This report presents new data from bulk density measurements carried out on selected rock samples as part of this comprehensive analytical program.