Clarence Richmond ppm thorium grid geodetichg

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 0.00042 degrees (approximately 43m) and shows thorium element concentration of the Clarence-Richmond Coastal Area, NSW, 1996 in units of parts per million (or ppm). The data used to produce this grid was acquired in 1996 by the NSW Government, and consisted of 48370 line-kilometres of data at a line spacing between 200m and 1600m, and 80m terrain clearance.

放射性测量法，又称伽马射线能谱法（gamma-ray spectrometric method），通过探测地表附近的伽马射线自然变化，表征钾（K）、铀（U）和钍（Th）天然放射性衰变所产生的辐射信号特征。所采集的数据将通过标准化流程进行处理，以确保记录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发布的最终数据符合使用需求。本放射性钍格网的像元大小为0.00042度（约43米），展示了1996年新南威尔士州（NSW）克拉伦斯-里士满沿海地区的钍元素浓度，单位为百万分之一（parts per million，简称ppm）。本格网所用数据由新南威尔士州政府于1996年采集，总测线长度达48370线公里，测线间距介于200米至1600米之间，飞行离地高度为80米。