GSWA Gascoyne 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 89m) and shows thorium element concentration of the Gascoyne, WA, 2005 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2005 by the WA Government, and consisted of 104897 line-kilometres of data at 400m line spacing and 60m terrain clearance.

辐射测量法（radiometric，亦称伽马能谱法（gamma-ray spectrometric method））可检测地表附近的伽马射线自然变化，以此反映由钾（K）、铀（U）及钍（Th）的天然放射性衰变所产生的辐射信号。所采集的数据将通过标准化流程进行处理，以确保记录的响应信号仅源于地下岩石的辐射。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要求。本次辐射测量钍元素网格的像元尺寸为0.00083度（约89米），展示了2005年西澳大利亚州（Western Australia，缩写WA）加斯科因（Gascoyne）区域的钍元素浓度，单位为百万分率（parts per million，简称ppm）。用于生成该网格的数据由西澳大利亚州政府于2005年采集，总数据覆盖长度达104897线公里，测线间距为400米，飞行离地高度为60米。