The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose.
This radiometric thorium grid has a cell size of 0.00042 degrees (approximately 43m) and shows thorium element concentration of the South West 1 (Moora), WA, 2011 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 137623 line-kilometres of data at 200m line spacing and 50m terrain clearance.
This GSWA South West 1 Moora Thorium Grid Geodetic is an airborne-derived radiometric thorium grid for the South West 1 (Moora), WA, 2011. The survey was acquired under the project No. 1240 for the geological survey of WA. The grid has a cell size of 0.00042 degrees (approximately 43m). A total of 137623 line-kilometres of data at a line spacing of 200m and 50m terrain clearance were acquired to produce this grid. This radiometric thorium grid shows thorium element concentration of the South West 1 (Moora), WA, 2011 in units of parts per million (or ppm). Details of the specifications of individual airborne surveys can be found in the Fourteenth Edition of the Index of Airborne Geophysical Surveys (Percival, 2014). This Index is also available online at http://pid.geoscience.gov.au/dataset/79134. Further up to date information about individual surveys can also be obtained online from the Airborne Surveys Database at http://www.ga.gov.au/oracle/argus/.
Percival, P.J., 2014. Index of airborne geophysical surveys (Fourteenth Edition).