Volcanic Facies and Volcanic Edifice in Paleogene Period at Xiongba-Delai District,Tibet

Volcanic facies,which have the characteristics of central volcanic edifice,can divided into explosive facies,extrusive facies and volcanic deposit facies.It is magma activity in South Tethyan oceanic crust subduction period in the collision process between Himalayan and Gangdese landmass.So the continental marginal arc volcanic rock was formed in Xiongba-Delai district,Tibet.