Research On Geological And Geochemical Characteristics Of YuShui Cu Polymetallic Deposit In Guangdong

Yushui Cu polymetallic deposit is a representative deposit in the east segment of the South China MVT(Mississippi valley type zinc-lead deposits)metallogenic belt.Based on the results of previous studies,ore field geological,ore deposit geological and geochemical studies have been carried out on the deposit in order to demonstrate its genesis.Field investigation results indicate the occurrence of stratabound and fault-controlling types of ore bodies in the deposits.The stratabound type of ore bodies occurs as layers or similar layers and contains ores with laminated structure,while the fault-controlling type of ore bodies exists as veins and has ores with net-vein structure.Based on veins cutting relation,ore texture and structure,and mineral assemblage,mineralization process for the deposit is divided into oxide(hematite-specularite)and sulfide(pyrite-chalcopyrite-sphalerite-galena)stages.Sulfur,lead,carbon and oxygen isotopic analyses have been done on several ore and gangue minerals.The analytical data are consistent with the derivation of sulfur,lead,and carbon possibly from reduced formations sulfate,old basement strata,and marine carbonate,respectively.Temperature and salinity of ore-forming fluids in the major mineralization stage of sulfides are defined mostly in the range of 110 to 220? and 8 to 15 wt%,respectively.These analytical results combined with ore deposit geological and geochemical data support the stratabound lower temperature hydrothermal origin of the Yushui Cu polymetallic deposit.