Gawler Craton Airborne Survey Merge Radiometrics - K equivalent concentration grid (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.This radiometric potassium grid 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 grid 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.放射性测量法（radiometric method），又称伽马能谱法（gamma-ray spectrometric method），可通过探测地表附近的伽马射线自然变化，表征由钾（K）、铀（U）与钍（Th）的天然放射性衰变所产生的辐射信号特征。所采集的数据将通过标准化流程进行处理，以确保记录的辐射响应仅源于地下岩石。经处理得到的数据集可用于地质解译，以揭示地下地质构造。经处理的数据将由GA地球物理学家开展质量核查，以确保GA发布的最终数据符合使用要求。 本次放射性钾含量网格的栅格单元尺寸为0.0004度（约41米），展示的是2017-2019年南澳大利亚（SA）高勒克拉通（Gawler Craton）航空磁测-放射性测量与数字高程模型（DEM）融合项目的钾元素浓度数据，单位为百分比（%）。本网格所用数据由南澳政府于2019年采集，总测线长度达166万公里，测线间距为200米，飞行离地高度为60米。 为抑制网格中的长波长波动，本次研究采用独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）的航空磁测数据，来管控测线网格的基准水平。