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  • Under the Community Stream Sampling and Salinity Mapping Project, the Australian Government through the Department of Agriculture, Fisheries and Forestry and the Department of Environment and Heritage, acting through Bureau of Rural Sciences, funded an airborne electromagnetic (AEM) survey to provide information in relation to land use questions in selected areas along the River Murray Corridor (RMC). The proposed study areas and major land use issues were identified by the RMC Reference Group at its inception meeting on 26th July, 2006. This report has been prepared to facilitate recommendations on the Lindsay-Wallpolla study area. The work was developed in consultation with the RMC Technical Working Group (TWG) to provide a basis for the RMC Reference Group and other stake holders to understand the value and application of AEM data to the study area. This understanding, combined with the Reference Group's assessment of the final results and taking in account policy and land management issues, will enable the Reference Group to make recommendations to the Australian Government.

  • The Broken Hill Managed Aquifer Recharge (BHMAR) project is part of a larger strategic effort aimed at securing Broken Hill's water supply and identifying significant water-saving measures for the Darling River system. Hydrogeological investigations to rapidly identify and assess potential MAR targets and groundwater resources over a large area (>7,500 km2), included acquisition of an airborne electromagnetics (AEM) survey, a 7.5 km drilling program (100 sonic and rotary mud holes), and complementary field and laboratory hydrogeochemical investigations. In this study, AEM mapping validated by drilling has identified significant groundwater resources and potential MAR targets within shallow unconsolidated Pliocene sediments at relatively shallow depths (25-100m). Pliocene sand aquifers comprise the fluvial Calivil Formation, with the shallow marine Loxton-Parilla Sands restricted to the southernmost part of the area. The Calivil Formation is widely distributed, and has high storage capacity and very high transmissivities (up to 50 l/s), with particularly good aquifers developed in palaeochannels at the confluence of palaeo-river systems. The hydraulic properties make the Calivil Formation aquifer potentially suitable for groundwater extraction and/or MAR injection, with excellent recovery efficiencies predicted. The aquifer is sandwiched between variably thick clay aquitards, and can be characterised as varying from a confined to a 'leaky confined' system. Post-depositional warping, tilting and discrete offsets associated with neotoectonics are also recognised. Entry-level risk assessments were carried out for a number of potential MAR targets, with a pre-commissioning semi-quantitative residual risk assessment carried out for a priority site. Assessment of 12 hazard types included hydrogeological modelling, laboratory column clogging studies and geochemical assessment to assess source water treatment requirements.

  • Under the Community Stream Sampling and Salinity Mapping Project, the Australian Government through the Department of Agriculture, Fisheries and Forestry and the Department of Environment and Heritage, acting through Bureau of Rural Sciences, funded an airborne electromagnetic (AEM) survey to provide information in relation to land use questions in selected areas along the River Murray Corridor (RMC). The proposed study areas and major land use issues were identified by the RMC Reference Group at its inception meeting on 26th July, 2006. This report has been prepared to facilitate recommendations on the Lindsay-Wallpolla study area. The work was developed in consultation with the RMC Technical Working Group (TWG) to provide a basis for the RMC Reference Group and other stake holders to understand the value and application of AEM data to the study area. This understanding, combined with the Reference Group's assessment of the final results and taking in account policy and land management issues, will enable the Reference Group to make recommendations to the Australian Government.

  • Presently, groundwater, through direct extraction (>30%), and indirectly through replenishing our river systems (>20%), contributes over 50% of Australia's water supplies. Groundwater (and surface water) management in Australia faces intensifying pressures, from population expansion and increasing surface water scarcity in southern Australia posed by extreme drought and future climate change. Recently, and significantly, new additional pressures on groundwater systems have emerged through the rapid expansion of new energy sources (coal seam gas, uranium, geothermal and carbon geo-sequestration) and a rapid expansion of the minerals resource sector (including iron ore). The complexity and conflicts in the nexus between water, new energy, minerals and food and fibre security require innovative approaches in science, management and policy. This is particularly the case in the context of Australia's inherent vulnerability to climate change and the likely emergence of a carbon economy. Quantification of the hydrological cycle and catchment water balances in Australia is limited by a lack of spatial and temporal data. While substantial effort has been put into developing approaches for the mapping and quantification of surface hydrology, resources and processes, significant uncertainty remains in the knowledge of the size of Australian groundwater resources, their locations, rates of recharge, connectivity with surface waters and rates of use or depletion. Recently completed groundwater audits and regional groundwater investigations have made valuable assessments of resources based on limited available data, but have not adequately quantified the large uncertainties in groundwater model predictions and resource assessments, or identified where and what data and knowledge is required to improve these assessments.

  • Under the Community Stream Sampling and Salinity Mapping Project, the Australian Government through the Department of Agriculture, Fisheries and Forestry and the Department of Environment and Heritage, acting through Bureau of Rural Sciences, funded an airborne electromagnetic (AEM) survey to provide information in relation to land use questions in selected areas along the River Murray Corridor (RMC). The proposed study areas and major land use issues were identified by the RMC Reference Group at its inception meeting on 26th July, 2006. This report has been prepared to facilitate recommendations on the Nangiloc - Colignan study area. The work was developed in consultation with the RMC Technical Working Group (TWG) to provide a basis for the RMC Reference Group and other stake holders to understand the value and application of AEM data to the study area. This understanding, combined with the Reference Group's assessment of the final results and taking in account policy and land management issues, will enable the Reference Group to make recommendations to the Australian Government.

  • During 2008 and 2009, and under the Australian Government's Onshore Energy Security Initiative, Geoscience Australia acquired airborne electromagnetic (AEM) data over the Pine Creek Orogen of the Northern Territory. The survey area was split into three areas for acquisition. VTEM data was acquired in the Kombolgie area east of Kakadu National Park between August and November 2008. TEMPEST data was acquired west of Kakadu National Park with the area split in two to facilitate the use of two aircraft: the Woolner Granite area in the north (this data set) was acquired between October and December 2008; and the Rum Jungle area adjoining to the south, was acquired between October 2008 and May 2009. The main purpose of the surveys was to provide additional geophysical/geological context for unconformity style uranium mineral systems and thereby promote related exploration. The survey data will also provide information on depth to Proterozoic/Archean basement, which is of general interest to explorers, and will be used as an input into ground water studues in the region.

  • This report summarises the result of a study into seawater intrusion into coastal aquifers in the Northern territory coastal plain using AEM data, down hole geophysics, and bore hole geology carried out by Geoscience Australia on behalf of the National Water Commission and in partnership with NRETAS. The study showed that ground-validated AEM is able to map areas of saline aquifers in the area and differentiate them from bedrock conductors.

  • This powerpoint was presented at a workshop in Alice Springs March 2011. The goal of the Pine Creek AEM survey is to characterise the electromagnetic response of Paleoproterozoic rocks, particularly graphitic units adjacent to Archean granite domes, and map these units in regions of extensive cover, such as the Woolner Granite, and Daly River Basin areas. The project will also attempt to map key sub-surface unconformities and structures which may have influenced mineralising fluids. Objectives To map unconformity and palaeochannel uranium host rocks To map the thickness of Kombolgie Subgroup rocks (depth to prospective interface) To map graphitic basement conductors To map the thickness of regolith cover.

  • Funded by the Australian Government's Onshore Energy Security Program the Pine Creek airborne electromagnetic (AEM) survey was flown over the Pine Creek Orogen and parts of the McArthur, Victoria River and Daly Basins in the Northern Territory between August 2008 and 24th May 2009. The survey comprises three survey areas: Kombolgie, east of Kakadu National Park; Woolner Granite, near Darwin; and, Rum Jungle, west of Kakadu National Park. The Pine Creek survey was the second regional AEM survey flown in Australia. The survey cost of $3 745 000 included a 29 900 line km flown at various line spacings (555m, 1666m and 5000m) and covered approximately 74 000 km2. The Woolner Granite and Rum Jungle survey areas were flown by Fugro Airborne Surveys Pty. Ltd. (FAS), for Geoscience Australia (GA), using the TEMPESTTM time-domain AEM system. The Kombolgie survey area was flown by Geotech Airborne Pty. Ltd VTEMTM time-domain AEM system. The Pine Creek AEM survey was designed to deliver reliable, pre-competitive AEM data to promote exploration for uranium, copper-gold, base metals, tin and nickel in both brownfields and greenfields areas. The survey area hosts several uranium deposits, including the Ranger Uranium Mine, Rum Jungle and Nabarlek.

  • A new Geoscience Australia Magnetic Anomaly Grid Database of Australia (MAGDA) has been developed. This database contains publicly available airborne magnetic grid data for on- and near-offshore Australia. Flight-line magnetic data for each survey have been optimally gridded and the grids matched in one inverse process. New composite grids at 250 m and 400 m grid spacing form the basis of the new fourth edition of the Magnetic Anomaly Map of Australia. Aeromagnetic traverses flown around Australia during 1990 and 1994 are used in both quality control of the grids they intersect, and also to constrain grid merging by forcing grid data, where intersected, to the level of the traverse data. Although matching and merging of many grids into a seamless compilation produces a pleasing result, without obvious short-wavelength artefacts, accurate long wavelength components of crustal origin are more difficult to obtain. Errors in the ?tilt? of individual surveys, due either to older instrumentation, errors in processing, or incomplete core-field removal, can lead to large long wavelength errors when hundreds of surveys are combined across thousands of kilometres. Quantification of the accuracy of long-wavelength components is only possible by comparison with independent datasets. A low-pass filtered composite grid of the Australian region has been compared with CHAMP satellite magnetic data, and shows a considerable improvement in the correlation of long wavelength components compared with the previous edition