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

  • 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.

  • 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.

  • The Exploring for the Future Program (EFTF) is a $100.5 million four year, federally funded initiative to better characterise the mineral, energy and groundwater potential of northern Australia. A key focus area of the initiative is the South Nicholson region, situated across the Northern Territory and Queensland border. The South Nicholson region is located between two highly prospective provinces, the greater McArthur Basin in the Northern Territory, the Lawn Hill Platform and the Mount Isa Province in Queensland–Northern Territory, which both have demonstrated hydrocarbon and base metal resources. In contrast, the South Nicholson region is not well understood geologically, is mostly undercover with limited well data, and prior to EFTF contained limited seismic coverage. Re–Os analyses in this study were undertaken to complement seismic data, U–Pb geochronology and geochemistry data to better understand the geological evolution and resource potential of the South Nicholson region. Five organic carbon bearing sedimentary samples from drillholes BMR Ranken 1, NTGS00/1, DDH 83/1 and DDH 83/4 located across the South Nicholson region were analysed for whole rock Re–Os. The aim of the analyses was to better constrain the depositional age of basin units in the region, and to potentially provide insights into the timing of post-depositional processes such as fluid events and hydrocarbon generation and/or migration. Samples belong to the Mesoproterozoic South Nicholson Group, Paleoproterozoic Fickling and McNamara groups, and the Neoproterozoic to Devonian Georgina Basin. Samples were analysed at the University of Alberta, Canada.

  • 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 Galilee 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. This Galilee 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 Galilee Basin is a large intracratonic sedimentary basin in central Queensland. The basin contains a variably thick sequence of Late Carboniferous to Middle Triassic clastic sedimentary rocks dominated by laterally extensive sandstone, mudstone and coal. These rocks were mostly deposited in non-marine environments (rivers, swamps and lakes), although there is minor evidence for marginal marine settings such as deltas and estuaries. Sedimentation did not occur continuously across the approximately 90 million year history of basin development, and intervals of episodic compression, uplift and erosion were marked by distinct depositional breaks. Over much of the surface area of the Galilee Basin the main aquifers targeted for groundwater extraction occur in the younger rocks and sediments that overlie the deeper sequence of the Galilee Basin. The primary aquifers that supply groundwater in this region are those of the Eromanga Basin, as well as more localised deposits of Cenozoic alluvium. However, in the central-east and north-east of the Galilee Basin, the Carboniferous to Triassic rocks occur at or close to surface and several aquifer units supply significant volumes of groundwater to support pastoral and town water supplies, as well as being the water source for several spring complexes. The three main groundwater systems identified in the Galilee Basin occur in the 1. Clematis Group aquifer, 2. partial aquifer of the upper Permian coal measures (including the Betts Creek beds and Colinlea Sandstone), and 3. aquifers of the basal Joe Joe Group. The main hydrogeological units that confine regional groundwater flow in the Galilee Basin are (from upper- to lower-most) the Moolayember Formation, Rewan Formation, Jochmus Formation and Jericho Formation. However, some bores may tap local groundwater resources within these regional aquitards in areas where they outcrop or occur close to surface. Such areas of localised partial aquifer potential may be due in part to enhanced groundwater storage due to weathering and fracturing.

  • This South Nicholson 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. This South Nicholson 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 South Nicholson Basin is a Mesoproterozoic sedimentary basin spanning Queensland and the Northern Territory and is bordered by neighbouring provinces and basins. The basin unconformably overlies the Lawn Hill Platform of the Mount Isa Province to the east, is bound by the Warramunga and Davenport provinces to the south-west, the Murphy Province to the north and the McArthur Basin to the north-west. It extends southwards under younger cover sequences. Rock units in the basin are correlated with the Roper Group in the McArthur Basin, forming the 'Roper Superbasin.' The underlying Mount Isa Province contains potential shale gas resources. The basin mainly consists of sandstone- and siltstone-bearing units, including the South Nicholson Group, with a prevailing east to east-northeast structural grain. Mild deformation includes shallowly plunging fold axes and numerous faults along a north-west to south-east shortening direction. Major geological events affecting the South Nicholson Basin region include the formation of the Murphy Province's metamorphic and igneous rocks around 1850 million years ago (Ma). The Mount Isa Province experienced deposition in the Leichhardt Superbasin (1800 to 1750 Ma) and Calvert Superbasin (1725 to 1690 Ma). The Isa Superbasin, with extensional growth faulting in the Carrara Sub-basin (~1640 Ma), deposited sediments from approximately 1670 to 1590 Ma. Subsequently, the South Nicholson Group was deposited around 1500 to 1430 Ma, followed by the Georgina Basin's sedimentation. The basin shows potential for sandstone-type uranium, base metals, iron ore, and petroleum resources, while unconventional shale and tight gas resources remain largely unexplored. The Constance Sandstone holds promise as a petroleum reservoir, and the Mullera Formation and Crow Formation serve as potential seals.

  • 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 South-east 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. Groundwater in Australia's fractured rock aquifers is stored in fractures, joints, bedding planes, and cavities within the rock mass, comprising about 40% of the country's groundwater. Much of this water can be utilized for irrigation, town water supplies, stock watering, and domestic use, based on state regulations. Fractured systems account for approximately 33% of all bores in Australia but contribute to only 10% of total extraction due to variable groundwater yield. Quantifying groundwater movement in fractured rock systems is challenging, as it depends on the distribution of major fractures. Groundwater flow direction is more influenced by the orientation of fractures than hydraulic head distribution. Recharge in fractured rock aquifers is typically localized and intermediate. In Eastern Australia, New South Wales' Lachlan Orogen, which extends from central and eastern New South Wales to Victoria and Tasmania, is a significant region with diverse lithological units, including deep marine turbidites, shallow marine to sub-areal sediments, extensive granite bodies, and volcano-intrusive complexes. This region contains various mineral deposits, such as orogenic gold, volcanic-hosted massive sulphide, sediment-hosted Cu-Au, porphyry Au-Cu, and granite-related Sn. Note: The study does not include additional Orogens in the east (New England) and west (Thomson and Delamerian). The Delamerian Orogen is present throughout western Tasmania.

  • We present a new geological map of Warrumbungle Volcano created from volcanic facies field mapping, new geophysical, geochemical, and geochronological data as well as data from previous studies. Field mapping and petrography defined 19 volcanic and 2 mixed volcanic-sedimentary facies. Facies identification and distribution in conjunction with geochemical analyses indicate an early shield-forming phase of predominantly mafic and intermediate lavas and pyroclastic deposits, and minor felsic lavas deposited on an irregularly eroded basement of Surat and Gunnedah basin rocks. The shield was subsequently intruded by felsic intermediate to felsic magmas that formed dykes and other intrusions including possible cryptodomes, and also erupted as lava domes and block-and-ash-flow deposits. A radial dyke swarm cross-cuts most units, although is concentrated within basement sandstone surrounding the central area of the volcano, suggesting late inflation accompanied by dyke emplacement. Geochemistry indicates differentiation of a single although repeatedly recharged alkaline magmatic suite. Fractionation of olivine, Ti-magnetite and clinopyroxene occurred in mafic magmas, and after reaching 62 wt% SiO2 crystallisation of apatite and alkali feldspar took place. A new U-Pb zircon SHRIMP magmatic crystallisation age of 16.25 +/- 0.12 Ma on a felsic block-and-ash flow deposit is in agreement with the recalculated 40Ar/39Ar isochron dates of previous workers. Based on our mapping and the use of volcanic facies to define mappable units, we recommend the previous Warrumbungle Volcanics be elevated from formation to group status and renamed the Warrumbungle Volcanic Complex.