Cobar P5009 EXT 4 Thorium ground concentration grid

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 0.00039074 degrees (approximately 40m) and shows thorium element concentration of the Cobar Magnetic and Radiometric Survey, 2021 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2021 by the NSW Government, and consisted of 53617 line-kilometres of data at 200m line spacing and 60m terrain clearance.

辐射测量法（radiometric method），或称伽马射线光谱法（gamma-ray spectrometric method），用于测量地球表面附近探测到的伽马射线的自然变化，这些变化源于钾（K）、铀（U）和钍（Th）的自然放射性衰变。所采集的数据通过标准方法处理，以确保记录的响应仅来自地下岩石。处理结果生成的数据集可通过解释揭示地下地质结构。GA的地球物理学家会对处理后的数据进行质量检查，确保GA发布的最终数据符合用途。
该辐射测量钍网格的单元格大小为0.00039074度（约40米），显示了2021年科巴磁测与辐射测量调查（Cobar Magnetic and Radiometric Survey, 2021）中钍元素的浓度，单位为百万分之一（ppm）。生成该网格所用的数据由新南威尔士州政府（NSW Government）于2021年采集，包含53617线公里的数据，线间距为200米，地形净空高度为60米。