In February 2009, Geoscience Australia released a new national radiometric map and dataset. This improved radiometric map, shows the distribution of potassium (K), uranium (U) and thorium (Th) at the Earth's surface as measured using the airborne gamma-ray spectrometric method. The gridded data that underpin the map cover over 80 % of the Australian continent at 100m spatial resolution. These data were calibrated to be consistent with an Australian radioelement datum based on an Australia wide airborne geophysical survey (AWAGS2) completed in 2008, which was conducted under the Australian Government funded Onshore Energy Security Initiative. AWAGS provides the baseline for stitching and levelling of all publicly available airborne radiometric (and magnetic) surveys across Australia, which are of a range of ages and qualities, and for future airborne surveys. The new grids of K, eTh and eU can be used to reliably compare the radiometric signatures observed over different parts of Australia, enabling the assessment of key mineralogical and geochemical properties of bedrock and regolith materials from different geological provinces and regions across the continent. These data support a range of different applications including exploration, geological mapping, geomorphological studies and environmental mapping.
Presented at AusIMM Uranium Conference, Darwin, 10 June 2009.
