Radiometric grid of Australia (Radmap) v4 2019 - Ternary image (K, Th, U)

This image is a ternary image of the radiometric grid of Australia, 2019. The radiometric grid of Australia is derived by merging over 600 airborne gamma-ray spectrometric surveys by the Commonwealth, State and Territory Governments and held in the national radioelement database of Australia. The cell sizes of the original survey grids range from 50 m through 800 m, but most have a cell size of about 100 m. The original survey grids are levelled to each other, and to the Australia Wide Airborne Geophysical Survey (AWAGS). The grids were then re-sampled to generate the Radiometric Map of Australia grids with a cell size of about 100m (0.001 degrees). Since the AWAGS traverses are consistent with the International Atomic Energy Agency’s (IAEA) radioelement datum, the new continental merges are levelled to this datum as well. The data quality varies depending on the survey. The data 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 final grid is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. The ternary image was generated by combining filtered K, Th and U grids. The grids were assigned the three usual hues of red (for potassium), green (for Thorium) and blue (for Uranium). This ternary image is very useful for both mineral exploration and environmental mapping.

本图像为2019年澳大利亚放射性辐射网格的三元合成图像。澳大利亚放射性辐射网格由联邦、州及领地政府开展的600余项航空伽马能谱测量数据合并生成，相关数据存储于澳大利亚国家放射性元素数据库中。原始测量网格的单元格尺寸介于50米至800米之间，其中绝大多数网格的单元格尺寸约为100米。原始测量网格之间已完成基准平差校正，且与全澳航空地球物理调查（Australia Wide Airborne Geophysical Survey, AWAGS）统一了测量基准。随后对上述网格进行重采样，生成单元格尺寸约为100米（0.001度）的澳大利亚放射性地图网格。由于全澳航空地球物理调查的测线与国际原子能机构（International Atomic Energy Agency, IAEA）的放射性元素基准一致，本次全新的洲际合并数据集也统一至该基准。数据质量因测量项目的不同而存在差异。数据通过标准流程进行处理，以确保所记录的辐射响应仅源于地下岩石。处理后得到的数据集可用于解译，以揭示地下地质构造。最终的网格数据由澳大利亚地质调查局（Geoscience Australia, GA）的地球物理学家进行质量核验，以确保GA发布的最终数据符合使用要求。本三元合成图像通过对经过滤波处理的钾（K）、钍（Th）和铀（U）网格数据合成生成，上述网格分别被赋予常规配色：红色代表钾，绿色代表钍，蓝色代表铀。该三元合成图像在矿产勘探与环境制图领域均具有极高的应用价值。