Characteristics of Volcanic Rocks and Analysis on the Prospecting Potentiality in Duocai Region,Zhiduo County,Qinghai Province

Duocai region lies in the east of Late Triassic Xijinwulan-Yidun island arc zone,belonging to the northwest of Sanjiang Metallogenic Belt.Galonggema copper-polymetallic deposit and Ladiouma copper mineralized spot have been discovered for many years in this belt.This paper focused on the characteristics of volcanic rocks which close to the mineralization in the area,restored volcanic apparatus and volcanic eruption environment,and discussed the relationship between volcanic activity and mineralization.Studies have shown that the volcanic rocks in this area are mainly dacite and dacitic pyroclastic rocks,followed by andesite,andesitic pyroclastic rocks.Trace elements of volcanic rocks enriched in lithophile elements Rb,Sr,Th and siderophile elements Co,Ni.Chalcophile elements and Zr is similar to the reference value,V and Ba contents are higher than the element abundance of the crust,and Sc,Cr are depleted.∑REE of intermediate-acidic volcanic rocks are higher,and general characteristics are similar with volcanic rocks of orogenic belt with negative Eu anomalies on the REE patterns.Volcanic phase of the overflow phase.Volcanic eruption was happen in shallow marine zone with structure environment of volcanic belongs to island-arc environment.Mineralization mainly related to ancient volcanic apparatus and the late dynamic metamorphism.