Alexandra, Vic, 2000 VIMP Survey (GSV3169) (P762), 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 Alexandra, Vic, 2000 VIMP Survey (GSV3169) (P762), radiometric line data, AWAGS levelled were acquired in 2000 by the VIC Government, and consisted of 23055 line-kilometres of data at 200m line spacing and 80m 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.

放射性测量法（radiometric method，亦称伽马能谱法（gamma-ray spectrometric method））通过探测地球表面附近的伽马射线自然变化，来反映钾（K）、铀（U）与钍（Th）的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于地下岩石的放射性衰变。经处理后得到的数据集可用于解译，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检查，以确保GA发布的最终数据符合使用要求。本次维多利亚州（VIC）亚历山德拉（Alexandra）2000年VIMP测量项目（GSV3169，编号P762）的放射性测线数据（已与澳大利亚全国航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）成果进行平差校正），由维多利亚州政府于2000年采集完成，测线总长23055线公里，测线间距为200米，飞行离地高度为80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——对本次测量数据的基准水平进行校正。本测量数据已基本完成AWAGS基准平差。