Ore-control Factors and Genesis of the Yingzuishan Altered Cataclastic Rock Type Gold Deposit, the West Sector of the Northern Qilian Mountains
YE Dejin ZHANG Zuoheng ZHAO Yanqing ( 1) School of the Earth Sciences and Resources , China University of Geosciences , Beijing, 100083; 2) Gansu Institute of Geological Survey, Lanzhou , Gansu, 730000; 3) Institute of Mineral Resources, CAGS, Beijing, 100037)
This paper gives a detailed description of the regional geological setting, metallogenic conditions, characteristics of ore bodies, alteration of wall rock, gold mineralization, and geochemistry of the Yingzuishan gold deposit. The deposit is mainly controlled by multi-grade fault system and pyroclastic rock. The gold mineralization is closely related to the cataclastic rock belt and the gold deposit is an alteration cataclastic rock type of gold deposit. The results of study on the homogenization temperature of fluid inclusions reveal that the ore-forming fluids characterized by middle-high temperature, low salinity and rich in CO2 and H2O. The data of stable isotope suggest that the ore-forming fluids is mainly from magmatic water in the early stage of mineralization and much meteoric water were mixed into the ore-forming system during the late stage.