The Lead Isotope Characteristics and Tracing Significance of Ore Metallogenic Material in the Geza Arc,Yunnan

Geza arc is the important parts of Yidun island arc in southwest of Sanjiang tectonic magmatic belts, it located in the southern tip of the Yidun island arc, which is a newly discovered copper polymetallic ore concentration area in the recently years in China. Based on the development stage of island arc orogenic, the distribution of intrusive rocks, composition, geochemical characteristics, Geza island arc granits belt can be divided into three belts. Geza island arc several typical porphyry deposits Pb isotopic data show that Pb206/Pb204 17.680~19.165, Pb207/Pb204 15.453~15.773,change in scope, Pb208/Pb204 37.730~39.654. Most of samples are normal lead, Pb isotopes focused on the side of orogenic evolution line and the lower crust range,with the characteristics of crust-mantle mixed source.