Radiometric Grid of Australia (Radmap) v4 2019 filtered terrestrial dose rate

The filtered terrestrial dose rate grid is a derivative of the 2019 radiometric or gamma-ray grid of Australia, made of a combination of over 600 individual survey grids. 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 are collected on airborne geophysical surveys conducted by Commonwealth, State and Northern Territory Governments and the private sector.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 the unfiltered grid to generate the filtered terrestrial dose rate grid. The grid cell size is about 100m (0.001 degrees).

经过滤波的陆地剂量率网格（filtered terrestrial dose rate grid）是澳大利亚2019年放射性（radiometric）或伽马射线网格的衍生数据集，由600余幅独立勘测网格整合拼接而成。放射性测量法或伽马射线能谱法（gamma-ray spectrometric method）可探测地球表面附近因钾（K）、铀（U）和钍（Th）自然放射性衰变所产生的伽马射线的天然变化。该数据集由澳大利亚联邦、各州及北领地政府与私营部门开展的航空地球物理勘测项目采集所得。未滤波的陆地剂量率网格由经过滤波的钾、铀、钍网格经线性组合计算得到，通过对该未滤波网格应用低通滤波器（low pass filter），即可生成该经过滤波的陆地剂量率网格。该网格的单元尺寸约为100米（0.001度）。