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  • Part- page item on matters related to the Australian Stratigraphy Commission and the Australian Stratigraphic Units Database. This column discusses the usefulness and vulnerability of type sections and reference sections.

  • Palaeogrographic analysis of the Early Cretaceous South Perth Supersequence.

  • Discusses requirements of a stratigraphic unit definition and why geoscientists should write more of them, where to research background information, where to get advice, and what standards apply.

  • 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.

  • One page article discussing aspects of Australian stratigraphy; this article is about the need for more unit definitions.

  • 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.

  • This Daly 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 Daly Basin is a geological formation consisting of Cambrian to Ordovician carbonate and siliciclastic rocks, formed approximately 541 million to 470 million years ago. The basin stretches about 170 km in length and 30 km in width, shaped as a northwest elongated synform with gentle dips of less than 1 degree, likely due to prolonged sedimentary deposition in the shallow seas of the Centralian Superbasin, possibly along basin-scale faults. The primary groundwater reservoir within the Daly Basin is found in the Cambrian Daly River Group. This group comprises three units: the Tindall Limestone, Jinduckin Formation, and Oolloo Dolostone. The Tindall Limestone, which lies at the base, consists of grey, mottled limestone with some maroon-green siltstone or dark grey mudstone. The transition from the Tindall Limestone to the overlying Jinduckin Formation is marked by a shift from limestone to more siliciclastic rocks, indicating a change from open-shelf marine to peri-tidal environments. The Jinduckin Formation, situated above the Tindall Limestone, is composed of maroon-green dolomitic-siliciclastic siltstone with interbeds of dolomitic sandstone-siltstone, as well as dolostone and dolomitic quartz sandstone lenses. It gradually transitions into the carbonate-rich Oolloo Dolostone, with the highest finely laminated dolomitic sandstone-siltstone interbeds at the top of the Jinduckin Formation. The Oolloo Dolostone, the uppermost unit of the Daly River Group, comprises two members: the well-bedded lower Briggs Member, consisting of fine- to medium-grained crystalline dolostone and dolomitic quartz sandstone, and the massive upper King Member. Overlying the Daly River Group is the Ordovician Florina Formation, consisting of three carbonate intervals separated by two fine-grained, glauconite-bearing quartz sandstone units. The Florina Formation and the Daly River Group are covered unconformably by Cretaceous claystone and sandstone of the Carpentaria Basin, which extends over a significant portion of the Daly Basin.

  • This Maryborough-Nambour 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 Maryborough Basin is a half-graben intracratonic sag basin mainly filled with Early Cretaceous rocks, overlain by up to 100 m of Cenozoic sediments. It adjoins the older Nambour Basin to the south, comprising Triassic to Jurassic rocks. The boundary between the basins has shifted due to changes in sedimentary unit classifications, with the Cretaceous units now restricted to the Maryborough Basin and Jurassic and older units assigned to the Nambour Basin. Both basins are bounded to the west and unconformably overlies older Permian and Triassic rocks in the Gympie Province and Wandilla Province of the New England Orogen. In the south of the Nambour Basin, it partly overlaps with the Triassic Ipswich Basin. The Nambour Basin in the south is primarily composed of the Nambour Formation, with interbedded conglomerate, sandstone, siltstone, shale, and minor coal. Overlying this is the Landsborough Sandstone, a unit with continental, fluviatile sediments and a thickness of up to 450 m. In the north, the Duckinwilla Group contains the Myrtle Creek Sandstone and the Tiaro Coal Measures, which were formerly considered part of the Maryborough Basin but are now associated with the northern Nambour Basin. In contrast, the Maryborough Basin consists of three main Cretaceous units and an upper Cenozoic unit. The Grahams Creek Formation is the deepest, featuring terrestrial volcanic rocks, volcaniclastic sedimentary rocks, and minor pyroclastic rocks. The overlying Maryborough Formation was deposited in a continental environment with subsequent marine incursion and includes mudstone, siltstone, minor sandstone, limestone, conglomerate, and tuff. The upper Cretaceous unit is the Burrum Coal Measures, comprising interbedded sedimentary rocks deposited in fluvial to deltaic environments. The uppermost unit, the Eocene to Miocene Elliott Formation, includes sandstone, siltstone, conglomerate, and shale deposited in fluvial to deltaic environments. Cenozoic sediments overlying the Elliott Formation consist of Quaternary alluvium, coastal deposits, and sand islands like Fraser Island, influenced by eustatic sea level variations. Volcanic deposits and freshwater sediments also occur in some areas. Adjacent basins, such as the Clarence-Moreton Basin and Capricorn Basin, have stratigraphic correlations with the Maryborough Basin. The Oxley Basin lies to the south, overlying the Ipswich Basin. In summary, the Maryborough Basin and the older Nambour Basin exhibit distinct geological characteristics, with varying rock formations, ages, and sedimentary features, contributing to the diverse landscape of the region.

  • 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 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.