Structural evolution and vein paragenesis at the Kumtor gold deposit, Kyrgyzstan

摘要

The Kumtor gold deposit, Kyrgyzstan, is hosted by Vendian carbonaceous phyllites of the Central Tien Shan. These rocks are in the hangingwall of the long-lived Kumtor Fault Zone, a splay off the regional-scale Nikolayev Lineament. Gold is associated with pyrite, and commonly tellurides, in complex hydrothermal breccias which postdate three mutually perpendicular ductile fabrics and related barren veins. This ground preparation allowed intensive interaction with auriferous fluids and teh formation of metasomatite, catastrophic pressure release and the development of chaotic breccias, and complex changes in oxidation state as these fluids interacted with carbonaceous host rocks.