GSWA South Yilgarn merged and levelled radiometric line data, AWAGS levelled

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 GSWA South Yilgarn merged and levelled radiometric line data, AWAGS levelled were acquired in 1987 by the WA Government, and consisted of 392575 line-kilometres of data at a line spacing between 100m and 400m, and 60m terrain clearance. To constrain long wavelengths in the data, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey data. This survey data is essentially levelled to AWAGS.

辐射测量法（radiometric，又称伽马射线能谱法）通过检测地球表面附近的伽马射线自然变化，表征钾（K）、铀（U）与钍（Th）发生天然放射性衰变所产生的辐射信号。所采集的数据将通过标准流程进行处理，以确保记录到的响应仅源自地下岩石。处理后得到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GA的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。本数据集为西澳大利亚州地质调查局（GSWA，Geological Survey of Western Australia）的南耶尔加恩合并校正辐射测量测线数据（已按澳大利亚全国航空地球物理调查（AWAGS，Airborne Geophysical Survey）标准校正），由西澳大利亚州政府于1987年采集，总测线长度达392575测线公里，测线间距介于100米至400米之间，作业飞行离地高度为60米。为约束数据中的长波长分量，项目采用独立数据集——澳大利亚全国航空地球物理调查（AWAGS）航空磁测数据，对本次调查数据的基准水平进行校正。本次调查数据实质上已按AWAGS标准完成基准校正。