Tanami NS 5S - Th 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 thorium grid has a cell size of 0.00018 degrees (approximately 20m) and shows thorium element concentration of the NTGS Tanami NS 5S Region Detailed Airborne Magnetic Radiometric and Digital Elevation Survey, NT, 2018 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2018 by the NT Government, and consisted of 15632 line-kilometres of data at 100m 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（radiometric or gamma-ray spectrometric method），亦称伽马能谱法，通过探测地表附近的伽马射线自然变化，量化钾（K）、铀（U）及钍（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处理，以确保记录到的响应仅源于地下岩石的辐射。经处理得到的数据集可通过解译，揭示地下地质构造特征。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发布的最终数据满足使用需求。
本辐射测量钍网格的单元尺寸为0.00018度（约20米），展示的是2018年北领地（Northern Territory，简称NT）北领地地质调查局（Northern Territory Geological Survey，简称NTGS）塔纳米（Tanami）NS 5S区域详细航空磁测、辐射测量与数字高程调查中的钍元素浓度，单位为百万分率（parts per million，简称ppm）。本网格的生产数据由北领地政府于2018年采集完成，总测线长度达15632千米，测线间距为100米，飞行离地高度为60米。为约束网格中的长波长信号，项目采用了独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey，简称AWAGS）的航空磁测数据，以校准本次调查网格的基准值。