Crustal thickness in Australia: where, how and what for?

Abstract

Geoscience Australia regularly undertakes crustal thickness measurements and it is the only National Agency that maintains a database of such measurements in Australia and its offshore territories, including the Australian Antarctic Territory. The most reliable estimates of crustal thickness come from refraction and wide-angle reflection seismic experiments, as well as from receiver function analyses. As of September 2007, there are only 474 crustal thickness measurements stored in Geoscience Australia?s database derived from such experiments. Crustal thickness data are essential for development of crustal scale tectonic models, assessment of geohazards, constraining of potential field inversions, estimation of crustal stretching rate in sedimentary basin modelling. Estimates of relative significance of depth of subsidence, basement heat production, and thickness of the crust for positioning of hydrocarbon maturation windows show that effects of crustal thickness can outweigh those of basement heat production.