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  • A brief summary fo the highlights of the Paterson AEM survey and planned future work of Geoscience Australia's Airborne EM Project.

  • Australia's ancient river networks are substantially obscured by dunefields. The depths of incision of the river valleys into bedrock, the nature of sedimentary infill, and the palaeoenvironmental and geomorphic evolution of these fluvial systems are little known for much of the continent. The fluvial systems are defunct and the valleys are now typically disconnected chains of salt lakes with the relict valleys governed by groundwater processes. The palaeovalley sediments represent important aquifers in widespread parts of the Australian semi-arid to arid zone. They commonly contain the only available water resources to support mining activities, remote Aboriginal communities, the pastoral industry, and groundwater-dependent ecosystems (GDEs). In Western Australia, investigations are underway in two regions to assess palaeovalleys and their groundwater resources: the Paterson Province in the Great Sandy Desert, and the Murchison Province of the Archean Yilgarn Craton. A variety of technologies have been applied to provide a regional context for more detailed analysis.

  • Geoscience Australia contracted an airborne electromagnetic (AEM) survey over the Frome Embayment, South Australia, under the Australian Government's Onshore Energy Security Program. The Frome AEM survey was acquired using the Fugro Airborne Surveys (FAS) TEMPEST fixed wing time-domain electromagnetic (TEM) AEM system. The acquisition and processing of data were carried out by FAS under contract to Geoscience Australia. The Frome AEM survey consists of 32 300 line km, covering a total area of 95 000 km2 and was flown between 19 May and 2 November 2010. The survey was designed to deliver reliable, pre-competitive AEM data and scientific analysis of the energy resource potential of the Frome region of South Australia, including the flanks of the Northern Flinders Ranges, the Frome Embayment, the Olary Ranges and the northwestern Murray Basin. The survey data may also be used as an input to groundwater studies in the region.

  • The Pine Creek airborne electromagnetic (AEM) survey is the largest undertaken in the Northern Territory to date, covering an area of 74,000km squared (roughly the size of Tasmania). Funded by the Australian Government's Onshore Energy Security Program at Geoscience Australia the survey was flown over the Pine Creek Orogen and parts of the McArthur, Victoria River and Daly Basins in the Northern Territory during 2008 and 2009 to enhance exploration for uranium and other mineral systems. Flight lines spaced at 1666m and 5000m were flown over several uranium deposits, including Whites, Dyson, Ranger and Nabarlek, as well as uranium prospects, including Thunderball. The Pine Creek survey comprises three areas: Kombolgie, east of Kakadu National Park; Woolner Granite, near Darwin; and Rum Jungle west of Kakadu National Park. The TEMPEST fixed wing AEM system was used to acquire data in the Woolner Granite and Rum Jungle survey areas. The TEMPEST survey data were publicly released by Geoscience Australia in July and September 2009, respectively. The VTEM helicopter AEM system was used in the Kombolgie survey area and those data were publicly released by Geoscience Australia in December 2009. Nine companies contributed financially to fly detailed areas within the Geoscience Australia funded lines at closer line spacings. Many more industry partners provided important drill hole information, historical EM datasets and access to cased holes for essential conductivity logging. All company infill AEM data will be released to the public domain in December 2010.

  • 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 PowerPoint presentation showing regional interpretations of data from the Frome airborne electromagnetic survey, presented at a workshop on 30 November 2011 at the University of Adelaide, South Australia

  • Airborne Electromagnetic data were acquired by Geoscience Australia in areas considered to have potential for uranium or thorium mineralisation under the Australian Government's Onshore Energy Security Program (OESP). The surveys have been managed and interpreted by Geoscience Australia's Airborne Electromagnetic Acquisition and Interpretation project. Government of South Australia Department for Manufacturing, Innovation, Trade, Resources and Energy (DMITRE), formerly the Department of Primary Industries and Resources South Australia (PIRSA), which changed name in October 2011 purchased infill. Three survey areas were recognised in the Frome AEM survey area and Cariewerloo traverses. Industry paid for infill - all of this data has now been released to the public domain and is available at the GA website. In contrast to industry style deposit scale investigations, these surveys are designed to reveal new geological information at regional scale. The Frome airborne electromagnetic data were acquired at line spacing's of between one and five kilometres, a total of 32 317 line km and covers an area of 95 450 km squared. The outcomes of the Frome AEM survey include mapping of subsurface geological features that are associated with unconformity-related, sandstone-hosted and palaeovalley-hosted uranium mineralisation. The data are also capable of interpretation for other commodities including metals and potable water as well as for landscape evolution studies. The improved understanding of the regional geology resulting from the Pine Creek survey results will be of considerable benefit to mining and mineral exploration companies. This Data Package is for Archive to the internal area of the CDS and contains all data, grids, images, mxd, shape files, documentation, licenses, agreements, interpretations and scripts used to create the Frome deliverables. At the projects completion (2012) all directories are required to be moved off the NAS. The reason to keep all the files is that more work is to be done on this data in the 2012-2015 period and these files may be needed in this future work.

  • The Southern Thomson Orogen VTEM-plus® Airborne Electromagnetic Survey was conducted by Geoscience Australia as part of a collaborative project with its partners the Geological Survey of New South Wales and the Geological Survey of Queensland. The Survey contributes to the Australian Academy of Science's UNCOVER Initiative and Geoscience Australia's response to this as part of the National Mineral Exploration Strategy. Geoscience Australia contracted Geotech Airborne Ltd to acquire VTEM-plus® airborne electromagnetic (AEM) data over part of the Southern Thomson Orogen in Queensland and New South Wales in April and May 2014. The data were also processed by Geotech Airborne Ltd using its FullWaveForm® processing techniques. The survey is designed to assess the under-cover geology and prospectivity of the Southern Thomson Orogen around Hungerford and Eulo and straddles the New South Wales-Queensland border. The survey comprises two parts: 1. A regular regional survey on 5000 m spaced East-West lines totalling 3352 line km and covering an area of 16 261 km2. 2. Two regional traverses adjacent various roads totalling 915 line km. The Southern Thomson Orogen is a priority area for mineral systems research. Much of the area lies underneath cover of sedimentary basins and is a poorly-understood element of Australia's geology. The Orogen contains Cambro-Ordovician rocks that have potential for Iron Oxide Copper-Gold (IOCG) resources, porphyry copper-gold and Volcanic-Hosted Massive Sulphide (VHMS) deposits. Survey data will add to knowledge of cover thickness and character and will inform future geological mapping in the region. The Southern Thomson Orogen VTEM-plus® AEM Survey data release includes the final contractor supplied (Phase 1) datasets AEM survey. The data will be available from Geoscience Australia's web site free of charge: http://www.ga.gov.au/about/what-we-do/projects/minerals/current/continental-geophysics/airborne-electromagnetics The data release package includes: 1. Point-located electromagnetic dB/dt and derived B-field data with associated position, altimeter, orientation, magnetic gradiometer, and derived ground elevation data. These data are in ASCII column format with associated README and ASEG-GDF2 header files. The dataset consists of a separate download file for the: a. Main survey block Part 1 (flight lines 1000-1171) b. Main survey block Part 2 (flight lines 1180-1360) c. Traverse lines (flight lines 3000-3006 and 4000-4007) d. Repeat lines e. High altitude lines. 2. Waveform files for every flight containing the 192 kHz sampling of the transmitter current and receiver waveforms. 3. Point-located conductivity estimates derived using the EM Flow® conductivity depth imaging (CDI) algorithm with associated position, altimeter, orientation, magnetic gradiometer, and derived ground elevation data. Data include the conductivity estimate for each 5 m interval and selected depth slices. These data are in ASCII column format with associated README and ASEG-GDF2 header files. All regular survey, traverses and repeat lines are included in a single download file. 4. Gridded data, at 1 km cell size in, for the conductivity depth slices derived from the EM Flow® CDI data, magnetics and elevation data in ER Mapper® binary raster grid format with associated header files. 5. Graphical multiplots, in PDF format, for each flight line showing EM Flow® CDI sections and profiles of Z-component dB/dt data, magnetics, powerline monitor, height and orientation data. 6. Operations Report. 7. ESRI shapefiles and KML files of flight lines. 8. Metadata and License files.

  • Airborne electromagnetic data (AEM) are used in many and diverse applications such as mineral and energy exploration, groundwater investigations, natural hazard assessment, agriculture, city planning and defence. Unfortunately, many users do not have access to a simple workflow for assessing the quality of the data that they are using. This poster outlines the main quality assurance and quality control (QA-QC) procedures used by Geoscience Australia for our 2008-11 AEM surveys. Minor processing errors can dramatically reduce the quality of the data to the point that interpreters will be unable to use the data, or worse still, will be misled by features or characteristics produced during acquisition and processing. These scenarios not only impact the application at the time of interpretation, but can seriously impact the reputation and perceptions of the AEM industry. Every effort should be made to ensure that maximum fidelity is preserved in the data during acquisition and processing so that the best possible data are available for interpretation. Geoscience Australia is embarking on a project to upgrade the National Airborne Geophysical Database to better manage the data from major AEM surveys. This will better preserve the data and associated documentation to allow users to access and take advantage of the data well into the future. The quality of historical data included in this endeavour will unfortunately be variable and dependent on the QA-QC standards of the time. Geoscience Australia currently holds over 150 000 line kilometres of AEM data funded by the Commonwealth Government, State Governments and industry. Much of this data is available online for download, but is not available via the Geophysical Archive Data Delivery System (GADDS). Geoscience Australia is planning the expansion of GADDS to accommodate AEM data into the future. It is hoped the procedures outlined on the poster will be widely accepted by users, in particular new users, as a set of minimum requirements to help ensure that AEM data will be of a consistent quality and to a higher standard acknowledging it as the valuable resource it is. Key words: Airborne electromagnetic data; National Airborne Geophysical Database; AEM; QA-QC.

  • This professional opinion assesses the viability of utilising the priority aquifer target GWMAR1 to secure Broken Hill's water supply, both as an extractive only scheme and as a conjunctive use scheme employing Managed Aquifer Recharge as a key component. This work comes under the arrangements of the Broken Hill Managed Aquifer Recharge Project Phase 3a Memorandum of Understanding. The report addresses, with confidence levels, the following issues: Option 1: Groundwater Extraction Only. This includes an estimation of the water storage capacity and ambient groundwater salinity of the GWMAR1 priority target and the Jimargil sub-area. Different confidence levels are attached to these two estimates, reflecting the focus of work to date on the Jimargil sub-area. Broader groundwater quality issues will also be discussed. An assessment is also made of the issues with respect to direct groundwater extraction as the sole option for securing Broken Hill's water supply for a minimum of 3 years (approximately 30GL). Option 2 assesses the use of the GWMAR1 priority aquifer as part of a conjunctive water supply incorporating Managed Aquifer Recharge. This includes an assessment of the suitability of the priority MAR target at Jimargil based on the National MAR Risk Assessment Guidelines. The report also includes specification of the remaining information gaps and potential risks to a project to utilise the aquifer for (1) Groundwater extraction and (2) a conjunctive supply utilising Managed Aquifer Recharge. Broken Hill and Menindee. The report also includes a short summary of communities in Australia that currently rely on Managed Aquifer Recharge to supply their potable water, and management issues associated with this supply, and future considerations to a possible implementation phase of providing water security to Broken Hill and Menindee from a regional aquifer.