Tanami NS 4NE - 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 4NE 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 10063 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 method，即伽马射线能谱法）可探测地球表面附近因钾（K）、铀（U）及钍（Th）自然放射性衰变产生的伽马射线的天然波动。所采集的数据将通过标准流程处理，以确保记录的响应仅由地下岩石引起。最终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，缩写GA）的地球物理学家开展质量核查，确保GA发布的最终数据符合使用要求。本次发布的钍元素辐射测量网格单元尺寸为0.00018度（约合20米），展示了2018年北领地（Northern Territory，缩写NT）NTGS塔纳米NS 4NE区域详细航空磁辐射测量与数字高程勘测（NTGS Tanami NS 4NE Region Detailed Airborne Magnetic Radiometric and Digital Elevation Survey）中的钍元素浓度分布，单位为百万分比（parts per million，即ppm）。用于生成该网格的数据由北领地政府于2018年采集，总测线长度达10063线公里，测线间距为100米，飞行地形离地高度为60米。为约束网格中的长波长信号，本次勘测采用了独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey，缩写AWAGS）的航空磁测数据，以控制本次勘测网格的基准水平。