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  • The Pine Creek AEM survey was flown over the Pine Creek Orogen in the Northern Territory during 2008 and 2009 as part of the Australian Government's Onshore Energy Security Program at Geoscience Australia (GA). The survey provides pre-competitive data for enhancing uranium and other mineral exploration. Flight line spacing was 1666 m and 5000 m covering an area of 74,000 km2 (roughly the size of Tasmania) which hosts several uranium deposits, including the Ranger Uranium Mine, Rum jungle, Ranger and Nabarlek. The region is also prospective for metals including copper, lead, zinc, gold, tin, rare earths, tantalum, tungsten, molybdenum and nickel. The Pine Creek AEM survey comprises three areas: Kombolgie to the east of Kakadu National Park; Woolner Granite near Darwin; and, Rum Jungle to the west of Kakadu National Park. Collaboration with the National Water Commission and eight private infill companies brought an additional investment of approximately $1 m into the survey, with follow-up exploration equal to or exceeding this amount. The Woolner Granite and Rum Jungle survey area data were acquired using the TEMPEST fixed wing AEM system. The acquisition and processing were carried out by Fugro Airborne Surveys Pty. Ltd., under contract to GA. The Woolner Granite and Rum Jungle surveys were flown between August 2008 and May 2009 and the data were publicly released by GA in July and September 2009 respectively. In the Kombolgie survey area, the data were acquired a by Geotech Airborne Pty. Ltd. using the VTEM helicopter AEM system. The survey was flown between August and November of 2008, and additional calibration flights relating to the survey were flown in April 2009. The Kombolgie data were publicly released by GA in December 2009.

  • The Ord is one of the largest rivers in northern Australia and is located in the Kimberley region of Western Australia. In this study we show that the lower Ord landscape near Kununurra in Western Australia consists of a large scale ancient landscape, possibly pre-Cambrian, being exhumed from beneath flat-lying Cambrian to Carboniferous cover rocks. Additional post-Permian landscapes are being formed by this process. The Ord Valley alluvium is of late Pleistocene to Holocene in age and consts off upward fining gravels, sands and clays infilling an inset valley profile. The Ord River initially flowed to the sea via the keep River estuary, however a major avulsion, possibly due to sedimentatain topping a low point in the surrounding valley walls, occurred possibly as recently as 1,800 years ago. As a result to mouth of the Ord shifted some 100 km to the east, to Cambridge Gulf, its course through the former alluvial plain and along the new course across the coastal plain was incised, and a scabland formed across the low point of Tararar Bar. This association of very ancient (pre-Paleozoic) landscape elements and by thin, very young weathering profiles and young sedimentary accumulations in alluvial valleys is paradoxical in the broader Australian pattern where very ancient landscape elements are associated with ancient sedimentary infill and weathering profiles.

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

  • 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.

  • 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 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.

  • In 2001, the Murray Darling Basin Commission (MDBC) funded a survey to collect airborne electromagnetic (AEM) datasets for Billabong Creek (GA Project # 904) under MDBC's Strategic Investigations and Education (SI&E) Program, as part of Airborne Geophysics - SI&E Project D2018. The project was a pilot testing the relevance of airborne geophysics data for salinity management, and evolved from the National Geophysics Project originally sponsored under the National Dryland Salinity Program. The data are now being publicly released through Geoscience Australia's National Airborne Geophysics Database.

  • The Capricorn 2013 AEM TEMPEST® survey, conducted as part of the Western Australia Exploration Incentive Scheme and managed by Geoscience Australia on behalf of the Geological Survey of Western Australia (GSWA), is a $2.5 million contribution to the Distal Footprints of Giant Ore Systems: UNCOVER Australia. The Capricorn 2013 AEM survey is Stage 1 of the WA Reconnaissance Airborne Electromagnetic Survey (WARAEM) 2013-20 National Geoscience Agreement project, designed to provide broad-acre, wide line-spacing, airborne electromagnetic (AEM) data over the approximately 70% of the area of Western Australia that is underlain by Precambrian rocks that occur at or within about 300 m of the surface. The Capricorn Orogen is a geologically complex area, the surface expression of which has a surface extent of approximately 240,000 square kilometres (approximately 9 per cent of the area of the State). It is prospective for potentially large discoveries of gold, copper, and other base metals. The Capricorn 2013 AEM TEMPEST data release includes the final contractor supplied (Phase 1) datasets from the TEMPEST® time domain AEM survey as well as a set of GSWA-produced imagery made from the data. The data release package includes: - Point-located, computed B-field EM time-series channel data in ASEG-GDF2 (ASCII) format (also TMI and terrain data) - Point-located computed conductivity and terrain data in ASCII format - Data multiplots (EM x- and z-component time series, CDI sections, TMI, altimeter and monitor channels) in PDF format - CDI stacked sections in PDF format - Gridded data: EM time constant (x- and z-components); selected conductivity-depth slices (in ER Mapper format, 1 km cell size) - Geo-referenced images of gridded EM data in JP2 format - Geo-referenced images of gridded TMI, Ternary Radiometrics, Bouger Gravity and DEM data in JP2 format - Flight path map in ESRI shapefile format - Survey operations report in PDF format - Metadata and License files

  • A guide to the use of AEM geophysics for mapping SWI in coastal landscapes and karstic aquifer systems in Australia. The project was funded by the National Water Commission (NWC), with significant in-kind resources and funding provided by Geoscience Australia (GA) and the Northern Territory Department of Resources, Environment, Tourism, Arts and Sports (NRETAS).