江南元古界层控金矿的地球化学和矿床成因

GEOCHEMISTRY AND METALLOGENESIS OF THE PROTEROZOIC STRATABOUND GOLD DEPOSITS IN THE JIANGNAN AREA, SOUTH CHINA

The Proterozoic stratabound gold deposits in the Jiangnan area, South China, have many transitional metallogenic features between that of typical metamorphic fluid and infiltrating hydrothermal solution from groundwater in geochemistry and can be classified into four subtypes and four mineralization styles. The present paper studies distribution characteristics of trace elements in gold-bearing formations and wall rock of the gold deposits, reveals a geochemical conjugation relationship between the concentration and impoverishment of Au and related elements in the mineralization process, and energy for forming the gold deposits by the data of trace elements and isotopic geochemistry. On the basis of the above advances, a metallogenic model is proposed of the gold deposits which involves ascending metamorphic fluid and circulating geothermal water under reconstitution and structure control.