Cobalt and HREE Minerals Systems in the Eastern Mount Isa Block

Ken Collerson is an Emeritus Professor in the School of Earth and Environmental Sciences at UQ and Principal at KDC Consulting. Prior to appointment at UQ he was Professor of Geochemistry at the University of California in Santa Cruz. Ken is an internationally recognised geoscientist whose research has provided a basis for predictive mineral system exploration. He is a specialist in exploration for technology (HREE, Sc) and battery (Li, Co Mn) metals, as well as PGEs and alkaline-hosted Au-Cu porphyry mineralisation.  His use of spinifex biogeochemistry to explore under cover in western Queensland, resulted in discovery of a 2000 km long plume generated Silurian to Devonian age mineral province in Australia.

A study of Co-rich samples from the Eastern Mount Isa Block was undertaken to constrain the IOCG mineral system and evaluate HREE prospectivity.  Although these deposits are interpreted to have had a granitic source, the element association includes metals not normally concentrated in silicic melts e.g., Co, Ni, Sc and PGE's.  Thus a more plausible explanation is that the mineral system reflects an ultramafic to mafic source. Discovery of HREE-rich cobalt mineralisation at Mount Cobalt, hosted by olivine-bearing pyroxenites, confirms this interpretation.  Au-rich siliceous sinters with epithermal textures show that hot springs occurred above these intrusions. The ultramafics were emplaced during plume induced Mesoproterozoic break-up of Columbia Supercontinent.