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  • This North-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. In fractured rock aquifers, groundwater is stored in the fractures, joints, bedding planes and cavities of the rock mass. About 40 per cent of groundwater in Australia is stored in fractured rock aquifers, and much of this may be available for irrigation, town water supplies, stock watering and domestic use. Approximately 33% of all bores in Australia are in fractured systems, representing about 10 per cent of total extraction. Groundwater yield is extremely variable, and dependent on the distribution of major fractures. However, rates of groundwater movement in fractured rock systems are difficult to quantify. Characterising groundwater flow in fractured rock aquifers is difficult with existing techniques, and groundwater flow direction can be related more to the orientation of fractures than to the hydraulic head distribution. Recharge in fractured rock aquifers is usually local and intermediate. The Queensland fractured rock is taken to be that part of the northern elements of the Eastern Fracture Rock provinces that extends from the southern part of the Laura Basin, south to the state boundary with New South Wales, and inland as far as the Bundock and Galilee Basins. It comprises the Mossman, Thomson and New England Orogens, and related Provinces. These include: i) The Mossman Orogen, including the Hodgkinson Province, and the Broken River Province; ii) The Thomson Orogen, comprising Neoprotozoic – Early Paleozoic Provinces, including the Anakie Province, Barnard Province, Charters Tower Province, Greenvale Province, and Iron Range Province; and iii) The New England Orogen, including the Gympie Province, Connors-Auburn Province, Yarrol Province, Wandilla Province, Woolomin Province, Calliope Province, Marlborough Province, and Silverwood Province

  • The Australian Government, through the National Water Infrastructure Fund – Expansion, commissioned Geoscience Australia (GA) to undertake the project ‘Assessing the Status of Groundwater in the Great Artesian Basin’ (GAB). The project commenced in July 2019 and will finish in June 2022. The aim of the project is to develop and evaluate new tools and techniques to assess the status of GAB groundwater system to support responsible management of basin water resources. A critical relationship exists between sediment depositional architecture and groundwater flow within and between GAB aquifers, and their connectivity with underlying and overlying aquifers. Little is known about lateral and vertical facies variation within the hydrogeological units and potential compartmentalisation and connectivity across the GAB. To improve the understanding of distribution and characteristics of Jurassic and Cretaceous sediments across the Eromanga/Galilee/Surat basins region, GA is compiling, processing and correlating a variety of well log data. Correlations have been made between geological units of similar age using palynological data from 322 key wells along 28 regional transects to standardise lithostratigraphic units, which are currently described using varying nomenclature, to a single chronostratigraphic chart across the entire GAB. The distribution of generalised sand/shale ratios calculated for 236 wells in the Surat and Eromanga basins are used to estimate the thickness of sand and shale in the different formations, with implications for formation porosity and the hydraulic properties of aquifers and aquitards. This study highlights regional lithological heterogeneity in each hydrogeological unit, and contributes to our understanding of connectivity within and between aquifers. This report and associated data package provide a first phase of data compilation on 322 key wells in the Surat and Eromanga basins to assist in updating the geological framework for the GAB. A data gap analysis and recommendations for building on this initial work are also provided.

  • 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.

  • 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 Laura 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 Laura Basin contains sedimentary rocks deposited between 168 and 102 million years ago during the Middle Jurassic to Early Cretaceous. The basin extends offshore beneath the Great Barrier Reef, and forms a bowl-shaped geologic feature. The strata have a maximum thickness of about 1,000 m in the north-central part of the onshore basin. Three main stratigraphic units comprise the stratigraphic succession of the Laura Basin, these being the Rolling Downs Group (Late Aptian to Albian, Cretaceous), the Gilbert River Formation (Lower Cretaceous to Jurassic) and the Dalrymple Sandstone (Upper to Middle Jurassic). The Rolling Downs Group was deposited in a shallow marine environment and has a basal shale unit (the Wallumbilla Formation) with minor siltstone and conglomerate bands overlain by marine silty and sandy claystone. The Gilbert River Formation was deposited in lagoonal to marginal marine environments and is dominated by clay-rich sandstone that is locally glauconitic and interbedded with minor calcareous siltstone, claystone and conglomerate. The Dalrymple Sandstone was deposited in lagoonal and fluvial environments and is dominated by sandstone with lesser claystone, siltstone, conglomerate, tuff and coal. The Laura Basin overlies older rocks of the Permian to Triassic Lakefield Basin, which extends northwards into surrounding marine waters, the Paleozoic metasedimentary rocks of the Hodgkinson region, associated with the Mossman Orogen, and Proterozoic basement rocks.

  • 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.

  • 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.

  • This Darling 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 geological Darling Basin, covering approximately 130,000 square kilometres in western New South Wales (with parts in South Australia and Victoria), is filled with over 8,000 m of mainly Devonian sedimentary rocks formed in various environments, from alluvial to marine. It sits atop regional basement structures, coinciding with boundaries between Late Paleozoic Kanmantoo, Lachlan, and Southern Thomson Fold Belts. The basin's outcrops are scarce, obscured by younger rocks and sediments. Sedimentary rocks from Late Silurian to Early Carboniferous periods make up the basin, with marine shales and fluvial quartz-rich sandstones being the most common. The Menindee and Bancannia Troughs rest unconformably over Proterozoic and Lower Paleozoic basement rocks, while eastern sub-basins onlap deformed and metamorphosed Lower Paleozoic rocks. A major tectonic shift at the end of the Ordovician transformed south-eastern Australia's palaeogeography from a marginal marine sea to deep troughs and basins. The Darling Basin's discrete sedimentary troughs formed in areas of maximum tectonic extension, including the Ivanhoe, Blantyre, Pondie Range, Nelyambo, Neckarboo, Bancannia, Menindee troughs, and Poopelloe Lake complex. Spatial variation in sedimentary facies indicates potential interconnections between the troughs. The western basin overlies Proterozoic and Lower Paleozoic rocks of the Paroo and Wonominta basement blocks, while the eastern basin onlaps folded, faulted, and metamorphosed older Paleozoic rocks of the Lachlan Fold Belt. The Darling Basin has seen limited hydrocarbon exploration, with wells mostly situated on poorly-defined structures. Indications of petroleum presence include gas seeping from water bores, potential source rocks in sparsely sampled Early Devonian units, and occasional hydrocarbon shows in wells. Reservoir units boast good porosity and permeability, while Cambrian to Ordovician carbonates and shales beneath the basin are considered potential source rocks.

  • 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 Southern 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. Crustal elements are crustal-scale geological regions primarily based on composite geophysical domains, each of which shows a distinctive pattern of magnetic and gravity anomalies. These elements generally relate to the basement, rather than the sedimentary basins. The South Australian Element comprises the Archean-Mesoproterozoic Gawler Craton and Paleo-Mesoproterozoic Curnamona Province, formed over billions of years through sedimentation, volcanism, magmatism, and metamorphism. The region experienced multiple continental-continent collisions, leading to the formation and breakup of supercontinents like Nuna and Rodinia, along with periods of extensional tectonism. Around 1,400 Ma, both the Gawler Craton and Curnamona Province were cratonised, and during the building of the Rodinia supercontinent (1,300-700 Ma), the present configuration of the region emerged. The area between the Gawler and Curnamona provinces contains Neoproterozoic to Holocene cover, including the Adelaide Superbasin, with the Barossa Complex as its basement, believed to be part of the Kimban Orogen. The breakup of Rodinia in the Neoproterozoic (830-600 Ma) resulted in mafic volcanism and extensional episodes, leading to the formation of the Adelaide Superbasin, characterized by marine rift and sag basins flanking the Gawler Craton and Curnamona Province. During the Mesozoic and Cenozoic, some tectonic structures were rejuvenated, while sedimentary cover obscured much of the now flatter terrain. Metamorphic facies in the region vary, with the Gawler and Curnamona provinces reaching granulite facies, while the Adelaide Superbasin achieved the amphibolite facies. The Gawler Craton contains rocks dating back to approximately 3,150 Ma, while the Curnamona Province contains rocks from 1,720 to 1,550 Ma. These ancient regions have undergone various deformation and metamorphic events but have remained relatively stable since around 1,450 Ma. The Adelaide Superbasin is a large sedimentary system formed during the Neoproterozoic to Cambrian, with distinct provinces. It started as an intracontinental rift system resulting from the breakup of Rodinia and transitioned into a passive margin basin in the southeast and a failed rift in the north. Later uplift and re-instigated rifting led to the deposition of thick Cambrian sediments overlying the Neoproterozoic rocks. Overlying basins include late Palaeozoic to Cenozoic formations, such as the Eromanga Basin and Lake Eyre Basin, which are not part of the assessment region but are adjacent to it.