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  • 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.

  • 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.

  • The upper Permian to Lower Triassic sedimentary succession in the southern Bonaparte Basin represents an extensive marginal marine depositional system that hosts several gas accumulations. Of these, the Blacktip gas field has been in production since 2009, while additional identified gas resources are under consideration for development. The sedimentary succession extends across the Permian–Triassic stratigraphic boundary, and shows a change in lithofacies changes from the carbonate dominated Dombey Formation to the siliciclastic dominated Tern and Penguin formations. The timing, duration, distribution and depositional environments of these formations in the Petrel Sub-basin and Londonderry High is the focus of this study. The sedimentary succession extending from the Dombey to the Penguin formations is interpreted to represent marginal marine facies which accumulated during a long-lasting marine transgression that extended over previous coastal and alluvial plain sediments of the Cape Hay Formation. The overlying Mairmull Formation represents the transition fully to marine deposition in the Early Triassic. Regional scale well correlations and an assessment of available biostratigraphic data suggest marginal marine deposition systems were initiated outboard before the End Permian Extinction event, subsequently migrated inboard at about the Permian–Triassic stratigraphic boundary, and continued to be deposited through the faunal and floral recovery phase as Triassic species became established. The depositional history of the basin is translated to a chronostratigraphic framework which has implications for predicting the character and distribution of petroleum system elements in the Petrel Sub-basin and Londonderry High. Appeared in The APPEA Journal 61(2) 699-706, 2 July 2021

  • One page article discussing aspects of Australian stratigraphy; this article discusses the issues to consider when reviewing and/or revising a unit or the stratigraphy of an area.

  • The national standard lexicon of geologic units, including: age, lithology, geologic relationships for all Australian geological units, and a record of their use in literature. Links to Geological Provinces and Geological Maps. The collection is maintained by Geoscience Australia on behalf of the Australian Stratigraphy Commission, a standing committee of the Geological Society of Australia. <b>Value: </b>The lexicon standardises terminology for geologic units, thereby enabling integration of different geologic studies and datasets. <b>Scope: </b>Covers all Australian Territories, including Australia's Antarctic Territories. The database contains over 17,500 current stratigraphic names and over 36,000 variations, most of which are superseded, obsolete, or misspelt versions of the current names. The publicly accessible portion of this collection is made available through the Australian Stratigraphic Units Database (ASUD), the national authority on stratigraphic names in Australia and can be accessed here: <a href="https://pid.geoscience.gov.au/dataset/ga/21884">https://pid.geoscience.gov.au/dataset/ga/21884</a>

  • The Mesoproterozoic South Nicholson Basin sits between, and overlies, the Paleoproterozoic Mount Isa Province to the east and the southern McArthur Basin to the northwest. The McArthur Basin and Mount Isa Province are well studied and highly prospective for both mineral and energy resources. In contrast, rocks in the South Nicholson region (incorporating the Mount Isa Province, the Lawn Hill Platform and the South Nicholson Basin, and geographically straddling the Northern Territory and Queensland border) are mostly undercover, little studied and consequently relatively poorly understood. A comprehensive U-Pb sensitive high-resolution ion microprobe (SHRIMP) zircon and xenotime geochronology program was undertaken to better understand the stratigraphy of the South Nicholson region and its relationship to the adjacent, more overtly prospective Mount Isa Province and McArthur Basin. The age data indicate that South Nicholson Basin deposition commenced ca. 1483 Ma, with cessation at least by ca. 1266 Ma. The latter age, based on U-Pb xenotime, is interpreted as the timing of postdiagenetic regional fluid flow. The geochronology presented here provides the first direct age data confirming that the South Nicholson Group is broadly contemporaneous with the Roper Group of the McArthur Basin. Some rocks, mapped previously as Mesoproterozoic South Nicholson Group and comprising proximal, immature lithofacies, have detrital spectra consistent with that of the late Paleoproterozoic McNamara Group of the western Mount Isa Province; this will necessitate a revision of existing regional stratigraphic relationships. The stratigraphic revisions and correlations proposed here significantly expand the extent of highly prospective late Paleoproterozoic stratigraphy across the South Nicholson region, which, possibly, extends even further west beneath the Georgina and Carpentaria basins. Our data and conclusions allow improved regional stratigraphic correlations between Proterozoic basins, improved commodity prospectivity and targeted exploration strategies across northern Australia. <b>Citation:</b> Carson, C.J., Kositcin, N., Anderson, J.R., Cross, A. and Henson, P.A., 2020. New U–Pb geochronology for the South Nicholson region and implications for stratigraphic correlations.. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

  • This South Australian Gulf and Yorke 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. The South Australian Gulf and Yorke Cenozoic basins consist of eleven separate basins with similar sediments. These relatively small to moderate-sized basins overlies older rocks from the Permian, Cambrian, or Precambrian periods and are often bounded by north-trending faults or basement highs. The largest basins, Torrens, Pirie, and Saint Vincent, share boundaries. The Torrens and Pirie basins are fault-bounded structural depressions linked to the Torrens Hinge Zone, while the Saint Vincent basin is a fault-bounded intra-cratonic graben. Smaller isolated basins include Carribie and Para Wurlie near the Yorke Peninsula, and Willochra and Walloway in the southern Flinders Ranges. The Barossa Basin, Hindmarsh Tiers, Myponga, and Meadows basins are in the Adelaide region. These basins resulted from tectonic movements during the Eocene Australian-Antarctic separation, with many forming in the late Oligocene. Sediment deposition occurred during the Oligocene to Holocene, with various environments influenced by marine transgressions and regressions. The well-studied Saint Vincent Basin contains diverse sediments deposited in fluvial, alluvial, deltaic, swamp, marine, littoral, beach, and colluvial settings, with over 30 major shoreline migrations. Eocene deposition formed fluvio-deltaic lignite and sand deposits, before transitioning to deeper marine settings. The Oligocene and Miocene saw limestone, calcarenite, and clay deposition, overlain by Pliocene marine sands and limestones. The uppermost sequences include interbedded Pliocene to Pleistocene limestone, sand, gravel, and clay, as well as Pleistocene clay with minor sand lenses, and Holocene to modern coastal deposits. The sediment thickness varies from less than 50 m to approximately 600 m, with the Saint Vincent Basin having the most substantial infill. Some basins were previously connected to the Saint Vincent Basin's marine depositional systems but later separated due to tectonic movements.

  • 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.

  • 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 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.