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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.

  • 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.

  • The Australian Flood Studies Database is available on line by Geoscience Australia via the Australian Flood Risk Information Portal. The database provides metadata on Australian flood studies and information on flood risk with a digital version where available. The purpose of the document is to guide new users in data entry and uploading of flood studies to a level acceptable for inclusion in the database.

  • Existing sources of water supply are described. Proposals for improving the supply of town water are considered. Further investigations are recommended with respect to tapping the southern lobe of the local basin, surface conservation, underground water resources, and the selection of a possible dam site.

  • Geoscience Australia (GA) was invited by Murray-Darling Basin Authority (MDBA) in 2010 to participate in an evaluation of the Intermap IFSAR (Interferometric Synthetic Aperture RADAR) data that was acquired as part of the Murray-Darling Basin Information Infrastructure Project Stage 1 (MDBIIP1) in 2009. This evaluation will feed into the business case for Stage 2 of the project. As part of the evaluation GA undertook the following: 1. A comparison of the IFSAR Digital Surface Model (DSM) and Digital Terrain Model (DTM) with a recent LiDAR acquisition, covering approximately 9000Km2 of the Lower Darling Region. It focused on assessment of the data over various land cover and terrain types and identified opportunities and issues with integrating IFSAR with LiDAR. 2. A comparison of the IFSAR Vegetation Canopy Surface (DSM minus DTM) with the Lower Darling LiDAR Canopy Elevation Model (CEM). 3. A comparison between currently mapped man-made and natural water bodies over the Murray-Darling Basin with the IFSAR derived products (water mask). 4. Application of the National Catchment Boundaries (NCBs) methodology to the IFSAR data and comparison with the delineated watersheds from PBS&J (Intermap's sub-contractor). This report outlines the findings of this evaluation based on the 4 items above MDBA requested.

  • We examine surface sediment and water column total nutrient and chlorophyll a concentrations for 12 estuaries with average water depths <4 m, and calculated sediment loads ranging from 0.2 to 10.8 kg m-2 year-1. Sediment total nitrogen, phosphorus and organic carbon concentrations vary inversely with sediment loads due to: (i) the influx of more mineral-rich sediment into the estuaries; and (ii) increasing sediment sulfidation. Sediment total organic carbon (TOC) : total sulfur (TS) and TS : Fe(II) ratios correlated to sediment loads because enhanced sedimentation increases burial, hence the importance of sulfate reduction in organic matter degradation. Curvilinear relationships were found between a weathering index and organic matter 13C in sediment, and sediment load. The rising phase of the curve (increasing weathering, lighter isotopic values) at low to intermediate loads relates to soil erosion, whereas regolith or bedrock erosion probably explains the declining phase of the curve (decreasing weathering, heavier isotopic values) at higher sediment loads. The pattern of change for water column total nutrients (nitrogen and phosphorus) with sediment loads is similar to that of the weathering index. Most water quality problems occur in association with soil erosion, and at sediment loads that are intermediate for the estuaries studied. Limited evidence is presented that flushing can moderate the impact of sediment loads upon the estuaries.

  • An area of about 12,000 square miles was mapped in the field seasons 1950-51. It contains four Pre-Cambrian rock groups ranging from Archaeozoic to Uppermost Proterozoic. The main groups in the area, the Mt. Isa and Lawn Hill Groups, are shallow-water geosynclinal sediments involved in a Proterozoic orogeny which resulted in fairly intensive folding along dominantly north-south axes, together with much faulting. The geological features discussed in this report include physiography, topography, stratigraphy, igneous activity, structure, mineral deposits and water supply.

  • With Australia's postwar immigration programme and the increased demand for food supplies, an expansion of Australia's rural industries is of primary importance, both to increase domestic food supplies and to obtain foreign exchange by export of primary produce. For such a development, the rainfall, surface and underground water resources are the factors of prime importance. In West Australia the difficulties met in finding water for farming purposes prevents rational development of many rural areas. Also, in some places town water supplies are insufficient or the water is saline. Water resources may be classified as follow: rain water from tanks or dams, water from bores or wells, water from old mine shafts (in mining districts), water from springs, [and] water from rivers. The present investigations are not concerned with the last two types of water supply. The following aims were set. 1. To test several types of instruments, to discover their limitations and ranges and the optimum conditions for their operations. 2. To estimate the accuracy of depth determination to discontinuities which might be related to the geology. 3. To investigate the possibility of distinguishing the nature of the discontinuities, for instance, decomposed granite, fresh granite, ground water level, etc., and the possibility of estimating whether ground water is fresh, brackish or saline. The tests areas were selected in the belief that sufficient bore information would be available to serve as controls. However, except at Austin Downs, near Cue, and at Big Bell, the bore information was generally insufficient, vague and unreliable. With the exceptions mentioned above, adequate records had not been kept. The purpose of the geophysical survey was not primarily to search for areas with favourable ground water occurrences but to test the resistivity method in areas where information on the occurrence of ground water was available from existing wells and bores. The order in which the tests are described in the report is: Wubin, Cue, Big Bell, Lake Grace and Kulkin.

  • On May 3rd, and again on June 1st, the author visited the Cotter dam to investigate a reported loss of water from the fault on the northern side of the wall. This report gives an account of these visits, together with the author's observations and conclusions in relation to the reported water loss.

  • At the request of the State Rivers and Water Supply Commission of Victoria, seismic tests using the refraction method were conducted over six well locations near Cobram in the Murray Valley Irrigation District of Central Northern Victoria. The purpose of the tests was to determine whether the depth of the water table in that area could be measured by seismic refraction methods. The problem of rising water tables is one which occurs commonly in irrigation districts. In some areas the problem is purely a local one in which only perched water tables, any within ten feet of the surface, are involved, but it is also possible that the level of the general water table over a large are may be raised by deep percolation. The State Rivers are Water Supply Commission have maintained a check on the water table depth in the Murray River Valley Irrigation District for some time by measurement in existing wells. These wells are not necessarily in the best positions, and some are falling in. The seismic method was considered as an alternative to expensive test boring for ground water measurement.