METAMORPHOSED VOLCANIC ROCKS IN NORTHWESTERN FUJIAN PROVINCE, CHINA: LITHOGEOCHEMISTRY AND TECTONIC SETTING

摘要

Rb-Sr and zircon U-Pb isotope studies indicate that the diagnetic age of the metamorphosed volcanic rocks in the northwestern Fujian Province, China, is 536-643 Ma. Systemic studies on petrochemistry, trace element geochemistry and Sr-Nd isotope geochemistry indicate that the diagenetic process of these rocks is the mixture melting of crust and mantle. These volcanic rocks were formed in the Later Sinian-Early Paleozoic island-arc setting, which developed on a basement of mature continent crust.