OVERVIEWS: Geology and mineralisation of Western Australia

Abstract

The evolution of Western Australian terrains spans over 4000 million years. During this time, a wide variety of mineral deposits have formed. The ca 2700 to 2500 Ma granitoid-greenstone terrains of the Yilgarn Craton are the most intensely mineralised with world-class nickel and gold deposits, as well as mineralised pegmatites. The Pilbara Craton is less well mineralised but is overlain by the Late Archaean to Palaeoproterozoic Hamersley Basin which contains world-class iron ore deposits. Proterozoic orogens and basins contain sporadic and locally important gold, copper, copper-nickel, lead-zinc, and uranium mineralisation. Diamondiferous lamproites and kimberlites have intruded within, and adjacent to, the Kimberley Craton since the Proterozoic. These include one of the world's largest diamond deposits at Argyle. The Canning Basin hosts late Paleozoic carbonate-hosted zinc-lead mineralisation. Since the Mesozoic, heavy-mineral sands have been deposited, mainly in the Perth Basin, and lateritic weathering has resulted in world-class bauxite deposits. This deep weathering has also resulted in supergene enrichment of gold, nickel, rare earth elements and uranium.