Petrogenesis of the Yaolinghe Group, Yunxi Group, Wudangshan Group Volcanic Rocks and Basic Dyke Swarms from Eastern Part of the South Qinling Mountains

The mid-late Neoproterozoic(676～833 Ma)Yao linghe Group,Yunxi Group,Wudangshan Group volcanic rocks and basic dyke swarms from eastern part of South Qinling Mountains produced an intracontinental rift setting.On the basis of geochemical data,the mid-late Neoproterozoic rift-related basic lavas and basic dykes from eastern part of South Qinling Mountains generally belong to a low Ti/Y (<500)magma type.Elemental and isotopic data suggest that the chemical variations of the mid-late Neoproterozoic rift-related basic lavas and basic dykes from eastern part of South Qinling Mountains can not be explained by cry stallization from a common parental magma.