Orogenic gold deposits in the Yilgarn craton: a review

摘要

Neoarchaean lode-gold deposits are commonly interpreted to have formed during a single late tectonic gold mineralization event. These deposits are associated with deep-sourced fluids channelled along crustal-scale shear zones hosted within quartz-filled fault and fracture meshes that formed in association with brittle-ductile shear zones. Deposit scale studies highlight the characteristics of gold mineralization and suggest a set of common characteristics including a spatial relationship to crustal-scale structures, an ore mineralogy dominated by quartz+/- carbonate vein with <3-5% Fe-sulfide minerals, the common presence of albite, micas, chlorite, scheelite and tourmaline in the altered host-rock and gold grades commonly comprised between 5 and 30 g/t. Regional field reconnaissance, deposit scale study and geochronology, together with literature review of studies conducted in the Yilgarn Craton including the Kalgoorlie, Leonora, Agnew and Wiluna districts, suggest that gold mineralization developed over successive stages punctuating the protracted and prolonged geological history of the Yilgarn Craton.