Geoscience Australia (GA) has initiated a program of Airborne Electromagnetic (AEM) acquisition under the Australian Government's Energy Security Initiative (2007 - 2011), to provide new data in geological provinces relevant for uranium exploration. The focus of this acquisition is directed at geologic architecture indicative of unconformity-related and paleochannel-hosted uranium potential. Three regional-scale projects have been established, Paterson, Pine Creek, and Frome Embayment-northwest Murray Basin. The Paterson project is centred on the Kintyre uranium deposit, and covers much of the surrounding exposed and near surface Proterozoic. Kintyre is hosted by Paleoproterozoic Rudall Complex which is unconformably overlain by Neoproterozoic sediments of the Yeneena Basin. Approximately 28 000 line km of TEMPEST data were acquired at line spacings of between 200 and 6000 m. Preliminary interpretation indicates contrasts in AEM response between outcropping Rudall Complex and formations of the Yeneena Basin. Interpretation of inverted AEM data will seek to map the unconformity in the sub surface. Gamma ray data indicate that the Rudall Complex and regionally extensive ferruginous duricrust contain above background uranium (>7 ppm U). Erosion and weathering of these sources has possibly moved substantial uranium into younger paleovalleys, some of which are evident in the acquired AEM data. These valleys have potential to host sandstone uranium and calcrete uranium deposits. The Pine Creek project is directed at AEM characterisation of Paleoproterozoic rocks, particularly graphitic units adjacent to Archean granite domes, and tracing these in regions of cover (e.g., the Woolner Granite area). The project will also attempt to map key sub-surface unconformities, and structures that may have controlled mineralisation. Acquisition for Geoscience Australia in the project area is at line spacings of 1.66 km and 5 km. VTEM acquisition in the east over the Pine Creek Orogen and overlying Kombolgie Subgroup has been completed. Acquisition of TEMPEST data farther west should be completed by mid June 09. The Frome Embayment - Murray Basin project will provide regional AEM data over a large area (80 000 km2) including known paleochannel-type uranium at the Beverley, Four Mile and Honeymoon deposits. Proposed infill flying at 1.66 km will be undertaken over the NW Murray Basin to test whether similar channel settings occur south of high-uranium granites and uranium occurrences in the Olary Province. The infill area also plans to map strand lines of the Murray Basin which may be prospective for thorium rich heavy mineral sands.

No abstract available

The Frome Airborne Electromagnetic (AEM) Survey was designed to deliver reliable precompetitive AEM data and scientific analysis to aid research into the potential of energy and mineral resources in the Lake Frome region of South Australia. The Survey was the third regional AEM survey conducted within the Onshore Energy Security Program (OESP) at Geoscience Australia (GA), following the Paterson and Pine Creek AEM surveys. The Survey was flown by Fugro Airborne Surveys (FAS) for Geoscience Australia between 22 May and 2 November 2010, using the TEMPEST^TM time-domain electromagnetic (TEM) system. Survey lines were flown east-west at a nominal 100m above ground level, and spaced 2.5km or 5km apart. A total of 32 317 line km of new data were collected over an area of 95 450km2, approximately one tenth of the area of South Australia. The survey area extends from the South Australia-New South Wales border at Cameron Corner across to the Marree and Leigh Creek areas, skirts the highland of the northern Flinders Ranges, and includes the entire Lake Frome area, the Olary Spur between the towns of Yunta and Cockburn and the northwestern Murray-Darling Basin. The Lake Frome region contains a large number of sandstone-hosted uranium deposits with known resources of ~60 000 tonnes of U3O8, constituting ~45% of uranium resources of this type in Australia. The Survey was conducted with the aims of reducing exploration risk, stimulating exploration investment and enhancing prospectivity within the region primarily for uranium, but also for other commodities including copper, gold, silver, lead, zinc, iron ore, coal and groundwater. The Frome AEM Survey was designed to be a regional mapping program for imaging surface and subsurface geological features that may be associated with sandstone-hosted uranium systems. Interpretations of the Frome AEM Survey data provide a regional overview of the under-cover geology of the entire survey area, as well as providing detailed along-line information to give users a greater understanding of previous detailed investigations within small areas. The data have mapped features of fertile sandstone-uranium systems and have highlighted many new areas of prospectivity for uranium and other commodities.

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 Boundary Bend - Nyah 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 Groups 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.

Airborne electromagnetic (AEM) systems are increasingly being used for mapping conductivity in areas susceptible to secondary salinity, with particular attention on near-surface predictions (ie those in the top 5 or 10 metres). Since measured AEM response is strongly dependent on the height of both the transmitter loop and receiver coil above conductive material, errors in measurements of terrain clearance translate directly into significant errors in predicted near-surface conductivity. Radar altimetry has been the standard in airborne geophysical systems for measuring terrain clearance. In areas of agricultural activity significant artifacts up to five metres in magnitude can be present. One class of error, related to surface roughness and soil moisture levels in ploughed paddocks and hence termed the ?paddock effect?, results in overestimation of terrain clearance. A second class of error, related to dense vegetation and hence termed the ?canopy effect?, results in underestimation of terrain clearance. A survey example where terrain clearance was measured using both a radar and a laser altimeter illustrates the consequences of the paddock and canopy effects on shallow conductivity predictions. The survey example shows that the combination of the dependence of AEM response on terrain clearance and systematic radar altimeter artefacts spatially coincident with areas of differing land-use may falsely imply that land-use practices are the controlling influence on conductivity variations in the near surface. A laser altimeter is recommended for AEM applications since this device is immune to the paddock effect. Careful processing is still required to minimise canopy effects.

In 2008, the Ord Irrigation Cooperative commissioned an airborne electromagnetics (AEM) survey of the ORIA Stage 1 and 2 areas to identify, quantify and understand any potential salinity risks in the current Ord irrigation area and the parts of the catchment that have been identified as potential future irrigation sites or potentially impacted by future irrigation. The project has been funded by the Australian and Western Australian governments through the National Action Plan for Salinity and Water Quality. Geoscience Australia and CSIRO were contracted to carry out the analysis and interpretation of the AEM dataset, and produce customised interpretation products. Some of the more specific questions it was hoped to address included: - Are we at risk of salinity in the Ord Catchment? - If so what areas are at the greatest risk? - Where can we target management to reduce this risk? - How can we plan future development to minimise salinity risk and maximise longevity of projects? The areas surveyed include the current Stage 1 Ord Irrigation Area, Stage 2 Irrigation Area (including Weaber and Knox Plains and Carlton Hill - Parry's Lagoon Conservation Area. The inclusion of undeveloped land in this survey is because the technology provides the opportunity to ensure any future irrigation development is guided by the best available information on soil type, aquifer quality and location and salinity risk. The information generated by this project will be publicly available and can be used for such things as: - Identifying leaky areas in the landscape that may require more concentrated management or can be designated for more suitable land use; - Where salt is stored in the landscape and at what depth, and where in the landscape it may influence plant growth; - Provide new constraints on the connectivity of aquifer systems in 3D across the ORIA and enable the construction of more realistic hydrogeological models to improve surface and groundwater management.

In 2008, the Ord Irrigation Cooperative commissioned an airborne electromagnetics (AEM) survey of the ORIA Stage 1 and 2 areas to identify, quantify and understand any potential salinity risks in the current Ord irrigation area and the parts of the catchment that have been identified as potential future irrigation sites or potentially impacted by future irrigation. The project has been funded by the Australian and Western Australian governments through the National Action Plan for Salinity and Water Quality. Geoscience Australia and CSIRO were contracted to carry out the analysis and interpretation of the AEM dataset, and produce customised interpretation products. Some of the more specific questions it was hoped to address included: - Are we at risk of salinity in the Ord Catchment? - If so what areas are at the greatest risk? - Where can we target management to reduce this risk? - How can we plan future development to minimise salinity risk and maximise longevity of projects? The areas surveyed include the current Stage 1 Ord Irrigation Area, Stage 2 Irrigation Area (including Weaber and Knox Plains and Carlton Hill - Parry's Lagoon Conservation Area. The inclusion of undeveloped land in this survey is because the technology provides the opportunity to ensure any future irrigation development is guided by the best available information on soil type, aquifer quality and location and salinity risk. The information generated by this project will be publicly available and can be used for such things as: - Identifying leaky areas in the landscape that may require more concentrated management or can be designated for more suitable land use; - Where salt is stored in the landscape and at what depth, and where in the landscape it may influence plant growth; - Provide new constraints on the connectivity of aquifer systems in 3D across the ORIA and enable the construction of more realistic hydrogeological models to improve surface and groundwater management.

The GILMORE project is a pilot study designed to test holistic systems approaches to mapping mineral systems and dryland salinity in areas of complex regolith cover. The project is coordinated by the Australian Geological Survey Organisation, and involves over 50 scientists from 14 research organisations. Research partners include: Cooperative Research Centres for Advanced Mineral Exploration Technologies (CRC AMET), Landscape Evolution and Mineral Exploration (CRC LEME), the CRC for Sensor Signal and Information Processing, and the Australian Geodynamics Cooperative Research Centre (AGCRC) Land and Water Sciences Division of Bureau of Rural Sciences (BRS) NSW Department of Land & Water Conservation and the NSW Department of Mineral Resources. Various universities including the Australian National University, University of Canberra, Macquarie University, Monash University, University of Melbourne, and Curtin University of Technology, and Australian National Seismic Imaging Resource (ANSIR). The project area lies on the eastern margin of the Murray-Darling Basin in central-west NSW. The project area was chosen for its overlapping mineral exploration (Au-Cu) and salinity management issues, and the availability of high-resolution geophysical datasets and drillhole materials and datasets made available by the minerals exploration industry. The project has research agreements with the minerals exploration industry, and is collaborating with rural land-management groups, and the Grains Research and Development Corporation. The study area (100 x 150 km), straddles the Gilmore Fault Zone, a major NNW-trending crustal structure that separates the Wagga-Omeo and the Junee-Narromine Volcanic Belts in the Lachlan Fold Belt. The project area includes tributaries of the Lachlan and the Murrumbidgee Rivers, considered to be two of the systems most at risk from rising salinities. This project area was chosen to compare and contrast salt stores and delivery systems in floodplain (in the Lachlan catchment) and incised undulating hill landscapes (Murrumbidgee catchment). The study area is characteristic of other undulating hill landscapes on the basin margins, areas within the main and tributary river valleys, and the footslopes and floodplains of the Murray-Darling Basin itself. Studies of the bedrock geology in the study area reveal a complex architecture. The Gilmore Fault Zone consist of a series of subparallel, west-dipping thrust faults, that juxtapose, from west to east, Cambro-Ordovician meta-sediments and granites of the Wagga Metamorphics, and further to the east, a series of fault-bounded packages comprising volcanics and intrusions, and siliciclastic meta-sediments. Two airborne electromagnetic (AEM) surveys were flown in smaller areas within the two catchments. Large-scale hydrothermal alteration and structural overprinting, particularly in the volcanics, has added to the complexity within the bedrock architecture. The data were originally published on 6 CDs. For ease of download the data have been zipped into the original structure. The contents are as follows: CD1 - An overview of the GILMORE Project with geophysical images, regolith map, drillhole locations, geophysical survey information and maghemite geochemistry. CD2 - Airborne Electromagnetic (AEM) images from the TEMPEST survey with vertical cross-sections linked to the flight lines CD3 - Integrated images of the Airborne Electromagnetic (AEM) data draped over the First Vertical Derivative of the Total Magnetic Intensity CD4 - Integrated images of the Airborne Electromagnetic (AEM) data draped over the First Vertical Derivative of the Total Magnetic Intensity CD5 - High resolution geophysical images from three detailed surveys and data from the Airborne Electromagnetic (AEM) QUESTEM survey CD6 - Geology, geochemistry, downhole data, 3 dimensional models, seismic data, and images linked to downhole point data.

No abstract available