Radiometrics Filtered K percent Image - 2015

Low-pass filtered K element concentration (percent K). The Radiometric Map of Australia dataset comprises gridsof potassium (K), uranium (U) and thorium (Th) element concentrations, and derivatives of these grids. This third edition was derived by seamlessly merging 45 new survey grids with the Second Edition Radiometric Map of Australia (Minty et al., 2010). Details of the specifications of individual airborne surveys can be found in the 2014 Edition of the Index of Airborne Geophysical Surveys (Percival, 2014). Matching of the grids in the database was achieved using a program called Gridmerge, originally developed within Geoscience Australia and has now been commercialised. This program was used to merge 45 new surveys to the Second Edition Radiometric Map of Australia. The second edition merged over 550 individual grids to create the compilation (Minty et al., 2009), and the Australia-wide Airborne Geophysical Survey (AWAGS) airborne radiometric data was used to control the base levels of those survey grids which overlapped the AWAGS data (Milligan et al., 2009). As the second edition was used as a base grid for the Gridmerge operation the new Third Edition is essentially levelled to AWAGS. Filtering: Potassium, uranium, thorium and dose rate grids are available in both filtered and unfiltered versions. The low-pass filtering was achieved by applying a 7-point, degree-3 Savitzky-Golay filter (Savitzky and Golay, 1964) to each of the original survey grids prior to grid merging.

低通滤波后的钾元素浓度（以钾百分比计）。
澳大利亚放射性填图数据集（Radiometric Map of Australia）包含钾（K）、铀（U）、钍（Th）元素浓度网格及其衍生网格。本次第三版通过将45份新测量网格与《澳大利亚放射性填图第二版》（Second Edition Radiometric Map of Australia, Minty等，2010）无缝拼接而成。
各航空测量项目的规格细节可查阅《航空地球物理测量索引2014版》（Index of Airborne Geophysical Surveys 2014 Edition, Percival，2014）。
数据库内网格的匹配通过名为Gridmerge的程序完成，该程序最初由澳大利亚地质调查局（Geoscience Australia）研发，目前已实现商业化。
该程序被用于将45份新测量数据拼接至《澳大利亚放射性填图第二版》（Second Edition Radiometric Map of Australia）。
第二版通过合并超过550份独立网格完成数据集汇编（Minty等，2009），并使用全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）的航空放射性数据对与AWAGS数据重叠的测量网格的基准水平进行校准（Milligan等，2009）。
由于第二版被用作Gridmerge拼接操作的基准网格，新版第三版实质上已按AWAGS数据完成水平校准。
滤波说明：钾、铀、钍及剂量率网格均提供滤波与非滤波两个版本。本次低通滤波通过在网格拼接前，对每份原始测量网格应用7点3阶萨维茨基-戈莱滤波器（Savitzky-Golay filter, Savitzky与Golay，1964）实现。