Sr Isotope Constraints on the Age and Source of Ore-Forming Materials of Gold Deposits, Southwestern Hunan

摘要

We have measured Rb and Sr concentrations in fluid inclusions of quartz in gold de- posits, southwestern Hunan. The Rb-Sr isochron ages of 435±9Ma and 412±33Ma are re- spectively determined, revealing that gold mineralization in this area took place in the Caledo- nian period rather than in the Wuling-xuefeng period as traditionally considered. Sr isotope geochemistry of the hydrothermal fluid indicates that the ore-forming materials are of crust ori- gin, derived largely from the ore-hosting strata rather than from the basic bikes.