St George ppm thorium grid geodetic

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 0.00021 degrees (approximately 22m) and shows thorium element concentration of the SMMSP - MagSpec - St George, Qld, 2001 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2001 by the QLD Government, and consisted of 61110 line-kilometres of data at a line spacing between 100m and 400m, and 60m terrain clearance.

放射性测量法，又称伽马能谱法，通过探测地球表层附近的伽马射线自然变化，表征钾（K）、铀（U）与钍（Th）的天然放射性衰变所产生的信号。所采集的数据将通过标准化流程进行处理，确保记录到的信号仅来源于地下岩石的放射性活动。经处理得到的数据集可通过地质解译揭示地下构造。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要求。
本放射性钍网格的单元格尺寸为0.00021度（约22米），展示了2001年昆士兰州圣乔治（St George）地区SMMSP-MagSpec项目的钍元素浓度数据，单位为百万分之一（ppm）。本网格所用数据由昆士兰州政府于2001年采集，总测线覆盖长度达61110线公里，测线间距介于100米至400米之间，飞行离地高度为60米。