Deep Structure beneath the Cenozoic Volcanic Zone in the Northern Qinghai-Tibetan Plateau and Its Cause of Formation Discussion

• 责任者：Zheng Hongwei (Department of Ceophysics ; Peking University ; Beijing 100871 ; China) ; Li Tingdong
• 刊名：Geoscience
• 出版年：2010
• 卷期：24(1)
• 关键词：火山岩 ; volcanic rocks ; 深部构造 ; deep-seated structure ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.131-139
• 图表：5 illus., 34 refs.
• 分类号：0801
• issnNo：ISSN1000-8527
• isbnNo：CN11-2035/P

There are a lot of Cenozoic potassic and ultrapotassic lavas in the northern Qinghai-Tibetan Plateau, their existing is an enigma. We have collected all the available arrival time data recorded by the temporary seismic stations and phase reports from the International Seismological Center in Tibet and its surrounding areas. In the tomographic inversion, we have used 139,021 P-wave arrival times from 9 649 teleseismic events recorded by 305 seismic stations. Tomographic images show that the frontier of the lithospheric mantle of Indian plate (ILM) sub-ducted beneath the center of Qiangtang terrane, and there is a great scale vertical low-velocity zone from deep to surface at the frontier of ILM. It supplies a channel for deep mantle upwelling.