Imaging Australia’s Lithospheric Architecture: Implications for our Understanding of Mineral Systems

Abstract:

Lithospheric structure and composition have direct relevance for our understanding of mineral prospectivity. Aspects of the lithosphere can provide a first-order constraint on the processes leading to mineral deposition at surface. These lithospheric features can be imaged using geophysical inversion or inferred from exhumed rock samples at the surface of the Earth, but it is a challenge to ensure consistency between competing models and datasets. The LitMod platform provides a probabilistic inversion framework that uses geology as the fabric to unify multiple geophysical techniques and incorporates a priori geochemical information. Here, we present results from the application of 1D LitMod to image the lithospheric architecture of the Australian continent. This includes lithospheric and crustal thickness, geotherms, mantle metasomatism, and physical properties. We validate these posterior predictions against independent studies to ensure robustness, and test mineral systems models applied to Australian deposits thereby advancing appraisal of mineral prospectivity in unmineralised terrains.