The Geochronology And Geology Meaning Study Of Zircon U-Pb Ages In Jiawula Pb-Zn-Ag Deposit,Inner Mongolia,China And Constrain To Mineralization

Mineralization,diagenesis and their relationships were highly controversial in Jiawula Pb-Zn-Ag Deposit.This paper reports the LA-ICP-MS and the SHRIMP zircon U-Pb geochronology of Jiawula granodiorite(JGD),quartz-porphyry(JQP)and dioritic-porphyry(JDP)and their geochemistry characteristics.JGD was formed at 248.3±4.8Ma,JQP was formed at 129±4.8Ma and JDP at 124±2.5Ma.According to geochronology and characteristics of porphyries mineralization,Jiawula Pb-Zn-Ag mineralization should be occurred among 129～124Ma.So this paper suggests that the JQP,JDP and Pb-Zn-Ag mineralization were all the products of the subduction of Mongolian-Okhotsk Ocean which was in transform stage from press to strench at that time.