The main part of this map is a Hue-Saturation-Intensity (HSI) image of De-trended Global Isostatic Residual Gravity data (DGIR) based on the B Series of the 2019 Australian National Gravity Grids. This series of grids represent the combination of 1.4 million ground gravity observations stored in the Australian National Gravity Database (ANGD) as of September 2019; 345,000 line km of Airborne Gravity and 106,000 line km of gravity gradiometry data in the National Australian Geophysical Database (NAGD), and the Global Gravity Grid developed at Scripps Institution of Oceanography, University of California at San Diego using data from the United States SIO, NOAA and NGA. The ground and airborne gravity data have been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940’s to the present day.
The shading of the image is from the northwest and the colour scale is linear from -500 µm.s-2 (blue) to +500 µm.s-2 (red).