Isostatic correction of New South Wales Bouguer gravity data

Abstract

The effect of the gravitational attraction of isostatic roots on the Bouguer gravity data for New South Wales is significant. The anomalies caused by isostatic compensation are most pronounced in the eastern third of the state. This is due to the load of the coastal mountain range being compensated, combined with the effect of the crustal thinning at the continental margin. To use the gravity data to interpret regional geological structure it is advisable to remove these large-amplitude longwavelength anomalies as they tend to obscure the anomalies caused by the geological structures of interest. A variety of methods is available to perform this. The method used here is a relatively simple method that assumes isostatic equilibrium and zero crustal rigidity.