Gawler Craton Airborne Survey Merge Radiometrics - K equivalent concentration image (AWAGS)

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.The Geological Survey of South Australia commissioned the Gawler Craton Airborne Survey (GCAS) as part of the PACE Copper initiative. The airborne geophysical survey was flown over parts of the Gawler Craton in South Australia. The program was designed to capture new baseline geoscientific data to provide further information on the geological context and setting of the area for mineral systems (http://energymining.sa.gov.au/minerals/geoscience/pace_copper/gawler_craton_airborne_survey). nThis radiometric potassium image has a cell size of 0.0004 degrees (approximately 41m) and shows potassium element concentration of the Gawler Craton Airborne Survey Magnetic Radiometric and DEM Merge, SA, 2017-2019 in units of percent (or %). The data used to produce this image was acquired in 2019 by the SA Government, and consisted of 1660000 line-kilometres of data at 200m line spacing and 60m terrain clearance. To constrain long wavelengths in the grid, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey grid.

辐射测量法（或称伽马射线能谱法）可探测地球表面附近因钾（K）、铀（U）和钍（Th）自然放射性衰变产生的伽马射线的自然变化。所采集的数据将通过标准流程处理，以确保所记录的响应仅源于地下岩石。由此生成的数据集可通过解译揭示地下地质构造。经处理的数据将由澳大利亚地质调查局（Geoscience Australia, GA）的地球物理学家开展质量核查，以确保该局发布的最终数据符合使用要求。
南澳大利亚州地质调查局委托开展高勒克拉通航空测量项目（Gawler Craton Airborne Survey, GCAS），作为PACE铜矿倡议的组成部分。本次航空地球物理调查覆盖了南澳大利亚州高勒克拉通的部分区域。本项目旨在获取全新的基础地质科学数据，为该区域成矿系统的地质背景与赋存环境提供更多参考依据（http://energymining.sa.gov.au/minerals/geoscience/pace_copper/gawler_craton_airborne_survey）。
本辐射测量钾元素图像的栅格单元尺寸为0.0004度（约合41米），展示了2017-2019年南澳大利亚州高勒克拉通航空磁测-辐射测量与数字高程模型（Digital Elevation Model, DEM）融合数据中的钾元素浓度分布，单位为百分比（%）。制作本图像所用的数据由南澳州政府于2019年采集，总飞行线路里程达166万千米，线间距为200米，飞行离地高度为60米。为约束网格内的长波长信号，项目采用了全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）的航磁数据，以校准本次测量网格的基准面。