Hydrothermal Alteration, Mineralization and Breccias at the Zijinshan High Sulfidation Cu-Au Deposit, Fujian Province, China

The Zijinshan ore field in Fujian province, southeast China formed during the Yanshanian period. The Zijinshan high sulfidation deposit is hosted by a 168 Ma granite pluton that was intruded by 110 Ma dacite dykes. Mineralization at Zijinshan is controlled by north-west trending normal faults which dip moderately to the northeast. These faults controlled the emplacement of the dacite dykes, mineralized breccias and syn-mineralized veins. Pre-mineralization matrix-rich breccias and syn-mineralization hydrothermally and dacite-cemented breccias are widespread. Hypogene Cu ores are hosted in veins and hydrothermally cemented breccias that cut the matrix-rich breccias. The matrix rich breccias are intensely quartz-altered. The hydrothermal cemented breccias are associated with dickite and alunite alteration. Oxide Au ores are associated with domain of intense silicic alteration.