The Western Davenport region has been identified as an area of interest for future agricultural development. However, realisation of this potential depends on access to a reliable supply of groundwater, underpinned by rigorous geological and groundwater information. A three-dimensional stratigraphic model has been created for the Western Davenport area of the Southern Stuart Corridor project under the Exploring for the Future program. Our interpretation integrates airborne electromagnetic data with historical drillhole and outcrop data to improve geological and hydrogeological understanding. Results show that stratigraphies of the Wiso and Georgina basins are equivalent and laterally continuous in this area. This enables a more complete hydrostratigraphy to be defined and underpins improved hydrogeological conceptualisation. New hydrochemical data support the conceptual model that the aquifers of the Wiso and Georgina basins are interconnected at a regional scale. The initial assessment of water quality indicates that groundwater may support further agricultural development. Analysis of new water chemistry data has improved understanding of groundwater processes and potential areas of recharge. This work will inform management decisions to enhance the economic and social opportunities in the Western Davenport area, while protecting the environmental and cultural value of water resources. <b>Citation:</b> Northey, J.E., Clark, A.D., Smith, M.L. and Hostetler, S., 2020. Delineation of geology and groundwater resources in a frontier region: Western Davenport, Northern Territory. 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.

<div>This was the last of five presentations held on 31 July 2023 as part of the National Groundwater Systems Workshop. Towards developing a 3D hydrogeological framework for Australia: A common chronostratigraphic framework for aquifers&nbsp;</div><div><br></div>

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.

This Murray 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 Murray Basin, a significant sedimentary basin in Australia, displays varying sediment thickness across its expanse, with the thickest layers concentrated in its central regions. The basin's geological evolution is characterised by distinct depositional phases. During the Paleocene to Eocene Renmark Group phase, sedimentary deposits encompass fluvial sands at the base, transitioning into paralic carbonaceous clay and lignite layers. These sediments indicate the shift from riverine to shallow marine environments, dating back to the Paleocene and Eocene periods. The Oligocene to Middle Miocene period encompasses the Ettrick Formation and Murray Group Limestone. The former includes marl, and the latter displays glauconitic grey-green marl and bryozoal limestone, revealing prevailing marine conditions during the Oligocene to Middle Miocene. In the Late Miocene to Early Pliocene Bookpurnong Formation, marine shelly dark grey clay and silt, previously known as the Bookpurnong Beds, coexist with Pliocene fluvial to marginal marine quartz sands (Loxton Sands), marking the transition back to terrestrial and nearshore marine settings. During the Late Pliocene to Pleistocene, the Blanchetown Clay, a substantial unit within Lake Bungunnia, signifies lacustrine phases. Overlying ferricretes in the central/eastern basin and the Norwest Bend Formation's oyster coquinas in the western region, the clay exhibits variable coloration and laminations. Lastly, the Pleistocene to Holocene phase witnesses river-induced reworking and erosion of underlying sediments, giving rise to the Shepparton and Coonambidgal formations. In the western Murray Basin, Cenozoic sedimentary rocks are relatively thin, typically measuring under 200-300 meters. The Renmark Trough area presents a maximum thickness of 600 meters.

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 Northern 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 Northern Australian Fractured Rock Province is a hydrogeological entity defined for this study, building upon earlier national-scale hydrogeological research. Australia's geological development was predominantly from west to east, with Archean rocks in the west, Proterozoic rocks in central Australia, and Phanerozoic rocks in the east. The North Australian Craton (NAC) is a significant tectonic element underlying 80% of the Northern Territory and extending to parts of Western Australia and northern Queensland, making up the core of the Northern Australian Fractured Rock Province. The NAC primarily consists of Paleoproterozoic rocks overlying Neoarchean basement. It is surrounded by Proterozoic terranes, including the Musgrave, Warumpi, and Paterson orogens to the south and south-west, the Terra Australis Orogen in the east, and the Western Australian Craton in the west. The Northern Australian Fractured Rock Province includes approximately twelve geological regions of mostly Proterozoic age, such as the Kimberley Basin, Speewah Basin, and Tanami Orogen, among others. Additionally, the province is partially overlain by the Kalkarindji Province, characterized by volcanic rocks. This widespread basaltic province serves as the basement for several significant sedimentary basins in northern Australia, including the Wiso, Ord, Bonaparte, Daly, and Georgina basins. In summary, the Northern Australian Fractured Rock Province is a hydrogeological region defined by combining various Proterozoic geological regions, mainly situated within the North Australian Craton. It is bounded by other Proterozoic terranes and covered in part by the Kalkarindji Province, which consists of volcanic rocks and forms the basement for several key sedimentary basins in northern Australia. Understanding this province is crucial for evaluating the hydrogeological characteristics and geological history of the region.

This Otway 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 Otway Basin is an elongated sedimentary basin located on the south-east continental margin of Australia. Covering approximately 150,000 square kilometres and stretching about 500 km from South Australia's Cape Jaffa to Victoria's Port Phillip Bay and Tasmania's north-west, most of the basin is offshore, with a smaller portion onshore. Geological studies of the Otway Basin have primarily focused on its hydrocarbon prospectivity, examining thick Cretaceous aged rocks both onshore and offshore. However, the shallower onshore sedimentary units are more relevant from a groundwater perspective. The basin's formation began with rifting between the Australian and Antarctic plates during the Late Jurassic, leading to regional subsidence and the development of the elongated sedimentary basin. Following the Cretaceous plate breakup, a passive margin basin formed, which subsequently underwent basin inversion, reverse faulting, and folding, interspersed with extensional periods and normal faulting. This complex evolution, combined with sea level variations and volcanic activity, resulted in numerous sedimentary cycles. The sedimentary succession in the basin comprises non-marine sediments and volcanic rocks from the Jurassic and early Cretaceous, with a period of tectonic compression interrupting sedimentation during the mid-Cretaceous. The late Cretaceous and Cenozoic sedimentary and volcanic rocks form the primary groundwater-bearing aquifers of the basin, with various sedimentary environments developing in the Neogene and Quaternary. The basin's structural geology is intricate, with numerous basement highs, sub-basins, troughs, and embayments. Fault systems are prevalent, separating tectonic blocks and potentially influencing groundwater flow, offering conduits for inter-aquifer connectivity. Overall, the Otway Basin's geological history has shaped its hydrocarbon potential and groundwater resources, making it an essential area for ongoing research and exploration in Australia's geological landscape.

<div>Reliable water availability is critical to supporting communities and industries such as mining, agriculture and tourism. In remote and arid areas such as in the Officer – Musgrave region of central Australia, groundwater is the only viable source of water for human and environmental use. Groundwater systems in remote regions such as the Musgrave Province are poorly understood due to sparse geoscientific data and few detailed scientific investigations. The Musgrave palaeovalley module will improve palaeovalley groundwater system understanding in the Musgrave Province and adjacent basins to identify potential water sources for communities in the region. This report summarises the state of knowledge for the region on the landscape, population, water use, geology and groundwater systems. An analysis of the current and potential future water needs under different development scenarios captures information on how water is used in an area covering three jurisdictions and several potentially competing land uses.</div><div>The Musgrave Palaeovalley study area is generally flat, low-lying desert country. The Musgrave, Petermann, Mann and Warburton ranges in the centre of the area are a significant change in elevation and surface materials, comprising rocky hills, slopes and mountains with up to 800&nbsp;m of relief above the sand plains. Vegetation is generally bare or sparse, with isolated pockets of grassy or woody shrub lands. Soils are typically Tenosols, Rudosols and Kandosols.</div><div><br></div><div>There are four main hydrogeological systems in the study area. These are the fractured and basement rocks, local Quaternary sediments regional sedimentary basins and palaeovalley aquifers. These systems are likely to be hydraulically connected. Within palaeovalleys, three main hydrostratigraphic units occur. The upper Garford Formation is a sandy unconfined aquifer with a clay rich base (lower Garford Formation) which acts as a partial aquitard where present. The Pidinga Formation represents a coarser sandy or gravelly channel base, which is partly confined by the lower Garford Formation aquitard. The aquifers are likely to be hydraulically connected on a regional scale. Further to the west, equivalent units are identified and named in palaeovalley systems on the Yilgarn Craton. </div><div><br></div><div>Groundwater is recharged by episodic, high-intensity rainfall events and mostly discharges via evapotranspiration. Recharge is higher around the ranges, and lower over the flatter sand plains. Palaeovalley aquifers likely receive some groundwater inflow from underlying basin systems and fractured rock systems. Regional groundwater movement is topographically controlled, moving from the ranges towards surrounding areas of lower elevation. In some palaeovalleys groundwater discharges at playa lakes. Water table gradients are very low. More groundwater isotope and tracer data is required to understand potential connectivity between basin, fractured rock and palaeovalley systems.</div><div>Groundwater quality is brackish to saline, although pockets of fresher groundwater occur close to recharge areas and within the deeper and coarse-grained Garford Formation. Groundwater resources generally require treatment prior to use Most groundwater in the region is suitable for stock use. </div><div><br></div><div>Existing palaeovalley mapping is restricted to inferring extents based on landscape position and mapped surface materials. Utilising higher resolution digital elevation models and more recently acquired remotely sensed data will refine mapped palaeovalley extents. Improving the modelling of the distribution and depth of palaeovalleys in greater detail across the region is best aided through interpretation of airborne electromagnetic (AEM) data.</div><div>Based on the successes of integrating AEM with other geoscientific data in South Australia, we have acquired 25,109 line km of new AEM across the WA and NT parts of our study area. We will integrate this data with reprocessed and inverted publicly available AEM data, existing borehole information, existing and newly acquired hydrochemical data, and new surface magnetic resonance data to model the three dimensional distribution of palaeovalleys in the study area. We will use these models and data as the basis for conceptualising the hydrogeology of the palaeovalley systems, and provide information back to local communities and decision-makers to inform water management decisions. The data will also provide valuable precompetitive information for future economic development in the region.</div><div><br></div>

This Gunnedah 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 Gunnedah Basin is an intracratonic, sedimentary basin in northern NSW. It forms the middle section of the greater Sydney-Gunnedah-Bowen Basin system and mainly consists of Permian and Triassic sedimentary rocks resting on Late Carboniferous to Early Permian volcanics. The Gunnedah Basin is overlain by the Surat Basin and the younger alluvial sediments associated with modern and ancient river systems. The Gunnedah Basin is not considered a single well-connected aquifer, rather a series of porous rock aquifers separated by several non-porous or poorly conductive layers. The Lachlan Fold Belt forms what is thought to be an effective basement although little information is known of its hydrogeological properties. All units of the Gunnedah Basin are of low permeability and significantly lower hydraulic conductivity than the overlying alluvial aquifers. Most of the groundwater resources in the area are extracted from either the overlying Surat Basin or younger alluvial aquifers. There is relatively little groundwater sourced from the aquifers of the Gunnedah Basin, except in areas where the overlying aquifers do not occur. The most viable groundwater source in the Gunnedah Basin are the more porous aquifers of the Triassic sequence.

Publicly available groundwater data have been compiled to provide a common information base to inform environmental, resource development and regulatory decisions in the Galilee Basin region. This web service summarises salinity, water levels, resource size, potential aquifer yield and surface water–groundwater interactions for the Galilee Basin located within the Galilee Basin region.