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  • Poster about the Woolshed Creek fossil site discovered by W.B. Clarke in 1844 now being rehabilitated as a geological heritage site, after Madura Parkway roadworks.

  • This Officer 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 Officer Basin is one of Australia's largest intra-cratonic sedimentary basins, spanning approximately 525,000 square kilometres. It contains a thick sedimentary sequence, ranging up to 10,000 m in depth, composed of rocks from the Neoproterozoic to Late Devonian periods. The basin features diverse depositional environments, including marine and non-marine siliclastic and carbonate units, evaporites, and minor volcanic deposits. The Neoproterozoic succession exhibits a range of depositional settings, including pro-delta to shelf, fluvial to shallow marine, lagoonal, glacial, and aeolian systems. The Cambrian to Ordovician sequence reveals evidence of fluvial, shallow marine, aeolian, sabkha to playa, and lacustrine settings. Volcanic rocks occur sporadically within the sequence, like the Cambrian Table Hill Volcanics in WA and the Neoproterozoic Cadlareena Volcanics in SA. The Officer Basin is considered a remnant of the larger Centralian Superbasin that formed during the Neoproterozoic, covering a vast region in central Australia. The Centralian Superbasin formed as a sag basin during the Tonian, accumulating fluvial, marine, and evaporitic sediments, followed by Neoproterozoic glacial deposits. The long-lasting Petermann Orogeny affected the earlier depositional systems, with extensive uplift along the northern margin of the basin leading to deposition of widespread fluvial and marine siliciclastic and carbonate sediments spanning the terminal Proterozoic to Late Cambrian. The Delamerian Orogeny renewed deposition and reactivated existing structures, and promoted extensive basaltic volcanism in the central and western regions of the basin. Later events are a poorly understood stage, though probably involved continued deposition until the Alice Springs Orogeny uplifted the region, terminating sedimentation in the Late Ordovician or Silurian. A suspected Late Devonian extensional event provided space for fluvial siliciclastic sediment deposition in the north-east. Today, the Officer Basin features four distinct structural zones: a marginal overthrust zone along the northern margin, a zone with rupturing by salt diapirs across the main depositional centre, a central thrusted zone, and a broad gently dipping shelf zone that shallows to the south.

  • 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 Western 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. The geological evolution of Australia can be summarised as a west-to-east growth pattern, resulting from the assembly and disintegration of several supercontinents since the Archean era. The oldest rocks are found in Western Australia, specifically within the Western Australia fractured rock province, which consists of two crustal elements: the West Australian Element and the Pinjarra Element. The Yilgarn and Pilbara cratons in the West Australian Element host the oldest rocks in continental Australia, featuring high-grade gneiss belts, granite-greenstone belts, and significant gold and iron ore deposits. The Yilgarn Craton is older in the west and can be divided into several terranes, with the eastern regions hosting world-class gold deposits. The Pilbara Craton, on the other hand, consists of granitoid-greenstone terrain and is rich in banded iron formations, leading to the world's richest iron ore deposits in the Hamersley Basin. The Gascoyne Province forms the medium- to high-grade metamorphic core of the orogeny in the West Australian Element. The Albany-Fraser Orogen and Paterson Orogen joined the West Australian Element with the South Australian and North Australian Elements, respectively, and are characterised by metamorphosed rocks of various facies. The Pinjarra Orogen, situated to the west of the Yilgarn-Pilbara block, contains granulite and amphibolite facies orthogneisses. In the Phanerozoic era, sedimentary cover occurred in various large and smaller basins in Western Australia. The West Australian Element, along with the adjoining orogens, is treated as the West Australian fractured rock province, primarily reliant on weathered and fractured zones for groundwater storage due to low permeability. These cratons and orogens have been exposed since the Precambrian or Late Palaeozoic era, experiencing substantial weathering and river valley development. Modern palaeovalleys are mainly infilled with Cenozoic sediments, while arid conditions have reduced active watercourses, leading to an abundance of Aeolian sand cover. Many of these palaeovalleys are no longer active as rivers but can still be identified topographically. Overall, the geological history of Australia reveals a complex and diverse landscape, with Western Australia playing a significant role in hosting some of the continent's oldest rocks and valuable mineral deposits.

  • part-page article on stratigraphic issues

  • This Amadeus 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 Amadeus Basin is a sedimentary basin in central Australia that spans from the Neoproterozoic to Late Devonian, potentially Early Carboniferous, periods. It contains clastic, carbonate, and evaporitic sedimentary rocks, with a total thickness of 6,000 m to 14,000 m. The Neoproterozoic section alone is up to 3,000 m thick and is divided into four super-sequences separated by major unconformities. The basin is an active hydrocarbon province, with ongoing oil and gas production and the potential for further discoveries. Several key petroleum source rock units have been identified in the Amadeus Basin. The Gillen Formation, found in the northeast, consists of marine black shale, dolostone, sandstone, and evaporite, reaching a maximum thickness of 850 m. The Loves Creek Formation comprises deep water grainstone and mudstone overlain by stromatolite-bearing grainstone and dolostone, with a thickness of up to 500 m. The Johnnys Creek Formation is a unit composed of red bed and dolomitic limestone or dolostone, along with siltstone and sandstone, up to 400 m thick. The Inindia beds consist of sandstone, siltstone, chert, jasper, tillite, and dolostone, with a maximum thickness of 2,000 m and were deposited in shallow marine conditions. The Aralka Formation is a siltstone and shale unit with two members, the Ringwood Member and the Limbla Member, reaching a thickness of up to 1,000 m. The Pertatataka Formation is a turbiditic red and green siltstone and shale unit, along with minor feldspathic sandstone, deposited in a deep marine or marine shelf environment, typically about 350 m thick but up to 1,400 m thick at certain locations. The Winnall Group is a succession of sandstone and siltstone, with a maximum thickness of 2,134 m. The Chandler Formation is a poorly exposed unit consisting of halite, foetid carbonate mudstone, shale, and siltstone, deposited in a shallow marine environment, with halite deposits reaching thicknesses of 230 m to 450 m. The Giles Creek Dolostone is a carbonate and siltstone unit, with minor sandstone, deposited in a shallow-marine environment. The Horn Valley Siltstone is a thinly bedded shale and siltstone, with nodular limestone and sandy phosphatic and glauconitic interbeds, serving as the primary hydrocarbon source rock in the basin. Lastly, the Stairway Sandstone is 544 m thick and divided into three subunits, consisting of quartzitic sandstone, black shale, siltstone, mudstone, and phosphorites.

  • The advent of Chemical Abrasion-Isotope Dilution Thermal Ionisation Mass Spectrometry (CA-IDTIMS) has revolutionised U-Pb dating of zircon, and the enhanced precision of eruption ages determined on volcanic layers within basin successions permits an improved calibration of biostratigraphic schemes to the numerical timescale. The Guadalupian and Lopingian (Permian) successions in the Sydney, Gunnedah, Bowen and Canning basins are mostly non-marine and include numerous airfall tuff units, many of which contain zircon. The eastern Australian palynostratigraphic scheme provides the basis for much of the local correlation, but the present calibration of this scheme against the numerical timescale depends on a correlation to Western Australia, using rare ammonoids and conodonts in that succession to link to the standard global marine biostratigraphic scheme. High-precision U¿Pb zircon dating of tuff layers via CA-IDTIMS allows this tenuous correlation to be circumvented¿the resulting direct calibration of the palynostratigraphy to the numerical timescale highlights significant inaccuracies in the previous indirect correlation. The new data show: the top of the Praecolpatites sinuosus (APP3.2) Zone lies in the early Roadian, not the middle Kungurian; the top of the Microbaculispora villosa (APP3.3) Zone lies in the middle Roadian, not the early Roadian; the top of the Dulhuntyispora granulata (APP4.1) Zone lies in the Wordian, not in the latest Roadian; the top of the Didecitriletes ericianus (APP4.2) Zone lies in the first half of the Wuchiapingian, not the latest Wordian; the Dulhuntyispora dulhuntyi (APP4.3) Zone is exceptionally short and lies within the Wuchiapingian, not the early Capitanian; and the top of the Dulhuntyispora parvithola (APP5) Zone lies at or near the Permo-Triassic boundary, not in the latest Wuchiapingian.

  • 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.

  • Palaeogrographic analysis of the Early Cretaceous South Perth Supersequence.

  • 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.