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  • The Surface Hydrology Points (Regional) dataset provides a set of related features classes to be used as the basis of the production of consistent hydrological information. This dataset contains a geometric representation of major hydrographic point elements - both natural and artificial. This dataset is the best available data supplied by Jurisdictions and aggregated by Geoscience Australia it is intended for defining hydrological features.

  • Poster prepared for International Association of Hydrogeologists Congress 2013 In this study, a multi-disciplinary systems mapping approach has completely revised our understanding of the age, stratigraphy, mode of deposition and landscape evolution of Lower Darling Valley (LDV) sediments within the north-western Murray Basin. The Cenozoic sequence in this area contains Paleogene and Neogene shallow marine, fluvial and shoreline sediments overlain by Quaternary lacustrine, aeolian and fluvial units. The surficial Quaternary fluvial units of the valley form a complex group of morphostratigraphic units which vary in their distribution, character and geomorphic expression through the study area. Resolving the distribution of these units has been particularly important for understanding surface-groundwater interactions. In the LDV Quaternary fluvial sequence, multiple scroll-plain tracts are incised into higher, older more featureless floodplains. Prior to this study, these were respectively correlated to the Coonambidgal and Shepparton Formations of the Riverine Plain in the eastern Murray Basin and associated with the subsequently discarded Prior Stream/Ancestral River chronosequence of different climatically controlled depositional styles. In contrast to that proposition, we ascribe all LDV Quaternary fluvial deposition to lateral-migration depositional phases of one style, though with more variable stream discharges and channel and meander-scroll dimensions. Successively higher overbank-mud deposition through time obscures scroll traces and provides the main ongoing morphologic difference. A new morphostratigraphic unit, the Menindee Formation, refers to the mostly older and higher floodplain sediments, where scroll traces are obscured by overbank mud which continues to be deposited by the highest modern floods. Younger inset scroll-plain tracts, with visible scroll-plain traces, are still referred to the Coonambidgal Formation. Another new stratigraphic unit, the Willotia beds, refers to even older fluvial sediments, now above modern floodplain levels and mostly covered by aeolian sediments. This work provides important insights into the nature of Australian Quaternary fluvial deposition, with important implications for hydrogeological processes, groundwater resources and the assessment of managed aquifer recharge options.

  • This project aims to characterise the hydrogeochemistry of groundwater associated with coal seams and surrounding aquifers in the Surat Region and Laura Basin. In addition, the project provides an assessment of the environmental values of groundwater in relation to ecological and human use, and general guidance on groundwater quality monitoring strategies. . Full details of the methodology and findings of the study, including limitations and assumptions are provided in this project technical report.

  • Poster prepared for International Association of Hydrogeologists Congress 2013 In this study, AEM mapping validated by drilling has enabled the lateral extents and thickness of the Pliocene aquifers to be identified. The Pliocene in this area dominantly comprises the fluvial Calivil Formation, with the shallow marine Loxton-Parilla Sands restricted to the southernmost part of the area. Post-depositional warping, tilting and discrete offsets associated with neotoectonics are also recognised. Facies analysis indicates the Calivil was deposited in deep braided streams across a dissected sedimentary landscape. Overall, the sequence is fining-upwards, with evidence for progradation over the Loxton-Parilla. Channel fill materials comprise gravels and sands, and local fine-grained units represent abandoned channels and local floodplain sediments. Integration of textural and hydraulic testing data has revealed there are five hydraulic classes within the Calivil,. At a local scale (10s to 100s of metres), there is considerable lithological heterogeneity, however at a regional scale (kms), sands and gravels are widely distributed with particularly good aquifers developed in palaeochannels and at the confluence of palaeo-river systems. Aquifer testing has revealed Calivil to be an excellent aquifer, with high storage capacity, and locally very high transmissivities (up to 50 l/s). Integration of the AEM data with borehole geophysical data (gamma, induction and NMR) and textural and pore fluid data has enabled maps of aquifer properties including groundwater salinity, porosity, storage and hydraulic conductivity to be derived. Overall, the multi-disciplinary approach adopted has enabled rapid delineation of new groundwater resources, and facilitated assessment of the Pliocene aquifers for managed aquifer recharge.

  • Poster prepared for International Association of Hydrogeologists Congress 2013 Surface-groundwater interactions are often poorly understood. This is particularly true of many floodplain landscapes in Australia, where there is limited mapping of recharge and discharge zones along the major river systems, and only generalised quantification of hydrological fluxes based on widely spaced surface gauging stations. This is compounded by a lack of temporal data, with poor understanding of how surface-groundwater interactions change under different rainfall, river flow and flood regimes. In this study, high resolution LiDAR, in-river sonar, and airborne electromagnetic (AEM) datasets (validated by drilling) have been integrated to produce detailed 3-dimensional mapping that combines surface geomorphology and hydrogeology. This mapping enables potential recharge zones in the river and adjacent landscape to be identified and assessed under different flow regimes. These potential recharge zones and groundwater flow pathways were then compared against the spatial distribution of discontinuities in near-surface and deeper aquitard layers derived from the AEM interpretation. These 3D mapping constructs provide a framework for considering groundwater processes. Hydrochemistry data, allied with hydraulic data from a bore monitoring network, demonstrate the importance of recharge during significant flood events. In many places, the AEM data also affirm the spatial association between fresher groundwater resources and sites of river and floodplain leakage. At a more localised scale, hydrogeochemical data allows discrimination of lateral and vertical fluxes. Overall, this integrated approach provides an important conceptual framework to constrain hydrogeological modelling, and assessments of sustainable yield. The constructs are also invaluable in targeting and assessing managed aquifer recharge (MAR) options.

  • Geoscience Australia was recently involved in the reconceptualisation of the hydrogeology of the Great Artesian Basin (GAB), as part of the Great Artesian Basin Water Resource Assessment. The project refined the understanding of key hydrostratigraphic units within the GAB. This brochure describes key aquifers in the GAB and is designed to be distributed with samples from the aquifers. Aquifers covered are the Winton-Mackunda, Cadna-owie-Hooray, Adori Sandstone/Springbok Sandstone, Hutton Sandstone and Precipice Sandstone. Brochure prepared for the International Association of Hydrogeologists Congress 2013, Perth, Australia

  • Workshop Proceedings of the National Coastal Groundwater Management Knowledge Transfer Workshop held in Canberra on 28-29 May 2013

  • Islands in the Pacific region rely heavily on their fresh groundwater, and for a number of islands it is the only reliable source of freshwater throughout the year. Stresses on groundwater resources in many Pacific Island countries are set to escalate in the future with projected population and economic growth. In addition, there are likely to be future climate impacts on groundwater availability and quality. Although a number of studies have been undertaken at a local scale, very limited information is available to consider the impacts of future climates on groundwater systems at a regional scale. This project provides a first-pass regional-scale assessment of the relative potential vulnerability of groundwater to: (i) low rainfall periods and (ii) mean sea-level rise for 15 Pacific Island countries and territories. The dataset associated with this report can be obtained from www.ga.gov.au using title "Pacific Island Groundwater Vulnerability to Future Climates Dataset" or catalogue number 81575.

  • This report describes the findings of the Great Artesian Basin Water Resource Assessment that have led to advancing the understanding of the GAB. It encapsulates findings that are presented in four region reports and a technical report on conceptualising the GAB that were prepared for the Assessment. Advancing the conceptual understanding of the GAB requires careful evaluation of the geological framework (i.e. the layers of rock), description of how the geology translates into hydrostratigraphy (i.e. the relative ability of specific layers to store and transmit water) and investigation of the groundwater conditions (i.e. watertable, groundwater levels, and inferred movement). It is the geological framework, hydrostratigraphy and groundwater conditions that are the basis for conceptualising water resources in the GAB. The conceptual understanding of the GAB provides the foundation for assessing water availability and providing guidance to water policy and water resource planning.

  • The approximate location of the Helidon Ridge (proposed name) - a basement ridge likely to define the hydrogeological boundary between the Surat and Clarence-Moreton basins in the GAB. To be used in conjunction with dataset 'Groundwater divide in the Hutton Sandstone boundary' (Geoscience Australia, Catalogue #77024, 2013) to define the easternmost boundary of the GAB. The approximate location of the Helidon ridge was interpreted from a GOCAD model layer of Base of Hutton Sandstone surface (Geoscience Australia dataset, Catalogue #76025, 2013). This data set provides an approximate location of Helidon ridge as a polygon in Shapefile format. The polygon represents the area in which the boundary is likely to be located, as the exact location is open to interpretation. Data is available in Shapefile format This data set was used in: Figure 5.3 in Ransley TR and Smerdon BD (eds) (2012) Hydrostratigraphy, hydrogeology and system conceptualisation of the Great Artesian Basin. A technical report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment. CSIRO Water for a Healthy Country Flagship, Australia. Figure 5.3 in Smerdon BD and Ransley TR (eds) (2012) Water resource assessment for the Surat region. A report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment. CSIRO Water for a Healthy Country Flagship, Australia Figure 14 in Smerdon BD, Marston FM and Ransley TR (2012) Water resource assessment for the Surat region. Summary of a report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment. CSIRO Water for a Healthy Country Flagship, Australia. 16pp. This dataset and associated metadata can be obtained from www.ga.gov.au, using catalogue number 75836.