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Updated:
13 March 2008
Onshore Energy Security Program - Five year Work Plan
Outline2007-08
2008-09
2009-10
2010-2011
Where will major datasets be acquired in the OESP?Australian Radioelement Datum and Upgraded National Magnetics DatabaseThe Australia-wide geophysical survey (AWAGS2) is acquiring airborne radiometric and magnetic tie-line data (Figure 1), to develop a new datum for re-levelling of previous airborne radiometric and magnetic surveys. The survey commenced in March 2007 in Albany WA , and flying is expected to be completed in the third quarter of 2007/2008. Using the new datum to merge and level hundreds of previous surveys, a new radioelement anomaly map of Australia will be delivered in 2008/09. It will show patterns in the near-surface concentrations of uranium, thorium and potassium as expressed by the gamma-ray flux from radioactive daughters of these elements. These data will be of direct benefit to explorers of uranium and thorium but will also find a range of uses in geological mapping and land management. Figure 1 Flight paths for the AWAGS2 airborne radiometrics and magnetics tie-line survey, at nominal line spacing of 75km in north-south direction and east-west along 1:1m map sheet boundaries and a nominal terrain clearance of 80m Figure 2 A map showing the updated progress of the magnetics and radiometrics survey as of 28 August 2007 Seismic reflection and magnetotelluric surveysPrevious seismic reflection surveys of Australian mineral provinces and basins (Figure 3) have demonstrated the utility of the method in imaging crustal structure, basin stratigraphy, and the architecture of mineral systems. Its application in the petroleum industry is unquestioned. There is growing use of seismic data by the mineral exploration industry to assist in area selection and targeting of mineralisation. More recently seismic data have been used by geothermal energy explorers in Australia. A major program of seismic data acquisition is underway (Figure 3) to image the crustal architecture and basins of regions considered prospective for uranium, hydrocarbons and geothermal energy. Seismic reflection data are a key tool in understanding continental evolution to identify relevant events, pathways and traps for uranium, hydrocarbons and buried granites. When integrated with other regional geological data and an understanding of the tectonic evolution, the new seismic data will enable prediction of possible areas of undiscovered mineral and energy resources. The advantages of deep versus shallow seismic acquisition are considered in the scoping of seismic surveys for each region. Figure 3 Summary of existing seismic surveys, recently acquired or in-progress surveys and regions of possible seismic reflection data acquisition in future years of the OESP. Magnetotelluric (MT) data acquisition is planned along OESP seismic lines. This method images variations in electrical conductivity through the crust. It is particularly useful in conjunction with seismic imaging in defining crustal- to regional-scale architecture and, in some circumstances, may directly image granites or parts of uranium and other mineral systems (e.g., alteration zones). See Appendix A1 for summary descriptions of proposed and possible seismic lines, and scientific justification. Airborne electromagnetic surveysAirborne electromagnetic surveying is now widely used in uranium exploration in Australia , particularly in the search for sandstone-hosted and unconformity-related uranium deposits. Nevertheless, there are vast areas of Australia where industry surveys are either non-existent or relatively small, and yet these areas have high potential for uranium. A major program of AEM surveys is planned in the OESP, aimed at providing new regional-scale datasets for such greenfields to brownfields uranium provinces. The AEM datasets will provide a regional context for more detailed existing or new industry electromagnetic surveys. The data will also be used to directly interpret the subsurface geology of the surveyed region, particularly in relation to uranium mineralising systems. For example the AEM conductivity data are expected to image palaeochannels and unconformities, both of which may be associated with uranium mineralisation. A summary of areas under consideration for airborne electromagnetic acquisition is given in Appendix two and is shown in Figure 4. A survey in the Paterson Province of WA is expected to commence in July 2007. A limited number of additional surveys will be flown during the OESP, subject to further scoping and prioritisation. Figure 4 Regions under consideration for airborne electromagnetic data acquisition during the OESP. Uranium potential compiled from Mines Atlas of Australia information Program newsA major AEM survey of the Paterson Province of northern Western Australia commenced in September 2007 (Figure 5). The results will be used to assess the region’s potential for uranium resources. The undeveloped Kintyre uranium deposit, discovered in 1985, and the operating Telfer gold mine are within the region of the new survey. This survey is the first of several AEM surveys being scoped across the continent to target uranium and thorium mineral systems. The AEM data will also be used for a variety of other purposes, such as land and water management. The acquisition of TEMPEST AEM data for the Paterson survey commenced on 11 September 2007. Surveying started at the eastern margin of the southern block and was completed Late November 2007. The Tempest system will remobilise to complete the Paterson northern survey area early April. Figure 5 Paterson AEM Survey National Geochemical Survey of AustraliaThe National Geochemical Survey of Australia (NGSA) involves collaboration with all States and the Northern Territory. Its purpose is to provide high quality, nationally consistent geochemical data and information regarding the distribution of elements, particularly those relating to geothermal and energy resources. Based on favourable experience from overseas surveys, and effective pilot surveys in Australia, the NGSA will be a low density survey. It will gather data on the geochemical composition of transported regolith at ~1400 sites around Australia. At each site, samples will be collected from the surface and the sub-soil. It is anticipated that the NGSA will provide valuable data and information relevant to:
Heat Flow MeasurementsHeat flow measurements are the most robust method of detecting areas of high heat flow. The thermal gradient is measured in drill holes of at least 300 m depth, and the thermal conductivity of rock are measured from samples of the drill core. Data will be acquired throughout the continent, but a desktop study of geothermal potential will be completed to provide a prioritisation for which areas should be studied in greater detail. Previous page: Introduction | Next page: National and regional project descriptions |
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