GSWA Hickman Crater Doserate 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. The terrestrial dose rate grid is derived as a linear combination of the filtered K, U and Th grids. A low pass filter is applied to this grid to generate the filtered terrestrial dose rate grid.This GSWA Hickman Crater Doserate Grid Geodetic has a cell size of 5e-05 degrees (approximately 5m) and shows the terrestrial dose rate of the South Pilbara, Hickman Crater, WA, 2011. The data used to produce this grid was acquired in 2012 by the WA Government, and consisted of 134742 line-kilometres of data at 400m line spacing and 60m terrain clearance.

放射性测量法（或称伽马能谱法，gamma-ray spectrometric method）通过检测地球表面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辐射信号。所采集的数据将通过标准化流程处理，以确保记录的辐射响应仅来自地下岩石。经处理得到的数据集可通过解译揭示地下地质构造。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需求。地面剂量率网格通过滤波后的钾、铀、钍网格的线性组合生成，随后对该网格应用低通滤波器（low pass filter），得到滤波后的地面剂量率网格。本GSWA希克曼陨石坑剂量率大地测量网格的单元尺寸为5×10^-5度（约5米），展示了2011年西澳大利亚州（WA）南皮尔巴拉地区希克曼陨石坑的地面剂量率分布。用于生成该网格的数据由西澳大利亚州（WA）政府于2012年采集，总测线覆盖长度达134742线公里，测线间距为400米，飞行离地高度为60米。