Predictive modelling of prospectivity for Pb–Zn deposits in the Lawn Hill Region, Queensland, Australia

Abstract

A combination of geodynamic modelling, mineral potential mapping, and mineral deposit studies are commonly used to explore for mineral deposits. This paper focuses on the mineral potential aspect, exploring the interrelationship between a knowledge-driven approach, which uses subjective evidence based on expert knowledge, and a data-driven model, based on Bayesian probabilistic reasoning. The limitations and strengths of these approaches provide an example of how blending human interpretation with computational models can be an effective way to aid exploration and ore genesis interpretation. The study is focused on the Lawn Hill Platform, Mount Isa Inlier, situated in Northwestern Queensland, Australia. The models are used to predict the mineral potential in the area, focussing on SEDEX (Sedimentary Exhalative Deposits) and VS (Vein Style) Pb–Zn mineralisation. The Lawn Hill Region shows good mineral potential close to the Termite Range Fault, within areas marginal to known prospects and vein/lode hosted deposits. However, there are lower favourability sites suggesting significant potential in the Kamarga Dome. Integration of the knowledge- and data-driven models is considered a potential way to more reliably assess the favourability of locating a Century-type system. The use of this combined technique suggests that the highest favourability of locating a shale-hosted mineralisation similar to Century is close to this deposit along the Termite Range Fault zone. One particularly prospective site has been identified north of the Edith cluster.