3D modelling of granite intrusions in northwest Tasmania using petrophysical and residual gravity data

摘要

Tasmania in southeast Australia is underlain by basement rocks dating from the Precambrian to the Cretaceous. One important event in the tectonic evolution of Tasmania is the intrusion of Devonian Granites which has resulted in metamorphism and mineralization in some regions. We construct a regional-detailed 3D model for northwest Tasmania including major geological units and estimate density values of each unit to investigate the tectonic setting and geometry of Devonian Granites. Our model contains 20 units with different density properties. The residual gravity data have been used to model the properties of these units and consequently the geometry of Devonian Granites. The new inversion refines the geometry of the Devonian Granites with respect to initial models. A new granite intrusion is also revealed by this study which is the subject of further investigation.