MRTAS Mathinna 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 0.0005 degrees (approximately 49m) and shows thorium element concentration of the NETGOLD - Mathinna, Tas , 1990 in units of parts per million (or ppm). The data used to produce this grid was acquired in 1990 by the TAS Government, and consisted of 1680 line-kilometres of data at 150m line spacing and 80m terrain clearance.

放射性测量法（radiometric method），亦称伽马能谱法（gamma-ray spectrometric method），通过探测地表附近的伽马射线自然变化，获取由钾（K）、铀（U）与钍（Th）天然放射性衰变所产生的伽马射线信号。所采集的数据将通过标准方法处理，确保记录的测量响应仅源于地下岩石的放射性衰变。经处理后的数据集可通过解译，揭示地下地质结构。GA的地球物理学家将对处理后的数据开展质量校验，确保GA对外发布的最终数据满足实际应用需求。本次发布的钍元素放射性测量网格，单元格尺寸为0.0005度（约合49米），展示了1990年塔斯马尼亚州马蒂纳地区NETGOLD项目的钍元素浓度分布，数据单位为百万分率（ppm）。用于生成该网格的数据由塔斯马尼亚州政府于1990年采集，总测线长度达1680测线公里，采用150米的测线间距与80米的离地高度完成采集。