GSQ Croydon 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 0.00083 degrees (approximately 90m) and shows thorium element concentration of the Croydon, Qld, 2007 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2007 by the QLD Government, and consisted of 100315 line-kilometres of data at 400m line spacing and 80m terrain clearance.

放射性测量法（或称伽马能谱测量法）通过检测地球表面附近的伽马射线自然变化，研究钾（K）、铀（U）和钍（Th）的自然放射性衰变过程。采集的数据经标准方法处理，确保记录的响应仅来源于地下岩石。处理结果生成的数据集可通过解译揭示地下地质结构。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预期用途。
该放射性钍网格的单元格大小为0.00083度（约90米），以百万分之一（ppm）为单位展示了2007年昆士兰州克罗伊登地区的钍元素浓度。生成该网格所用的数据由昆士兰州政府于2007年采集，包含100315线公里的数据，线间距为400米，地形净空高度为80米。