Cenozoic volcanism and intraplate subduction at the northern margin of the Tibetan Plateau

Abstract

Developed in the Mt. Kunlun orogenic belt at the northern margin of the Tibetan Plateau is an active Cenozoic volcanic zone which is more than 1000km in length and some ten to hundred kilometers in width. It extends east-westwards and is roughly parallel to the strike of Mt. Kunlun. The Cenozoic volcanic rocks are divided into the northern (N-) and southern (S-) subzones. Eruptions of volcanic lavas in the S-subzone are related to an initial rift zone within the north Qiangtang terrane, but the volcanic rocks in the N-subzone are relatively close to the contact zone between the Mt. Kunlun and the Tarim terrane. The space-time distribution, petrological and geochemical features can be explained by a model of southward intraplate subduction of the Tarim terrane.