A 3D shear-wave velocity model of the upper mantle beneath China and surrounding areas
Time:9:30 a.m., August, 7, 2014
Location:Meeting Room, LCG-CAS
Speaker:Xiaohui Yuan
Abstract:We present a three-dimensional model of shear wave velocity for the upper mantle of China and the surrounding region by multi-mode Rayleigh wave tomography. The procedure involves combination of 1-D path average models obtained by modeling each Rayleigh waveform up to the 4th higher mode in a tomographic inversion scheme. The seismic lithosphere, as it is defined by the crust and the high velocity mantle lid, is to the first order thin in east China and thick in the west, with a high velocity lid extending down to about 200 km depth beneath much of the Tibet-Pamir plateau. Beneath India, the thickness of the seismic lithosphere gradually increases from ~100 km in south India to more than 150 km in north India, where it underthrusts the Tibetan plateau to approximately the Jinsha River Suture. High velocity lid extending down to 100-150 km depth are also observed in the Tarim basin, Sichuan basin and Ordos block. The thickness of the lithosphere is 70-80 km or less in East China. A large-scale subhorizontal high velocity body is observed at depths of 150-400 km beneath the entire East China cratonic areas. This high velocity body might be the remnant of a delamination process which resulted in the decratonization of the North China and the Yangtze cratons.
Curriculum Vitae:
Dr. Xiaohui Yuan
Helmholtz Centre Potsdam
GFZ German Research Centre for Geosciences
Section 2.4 – Seismology
Telegrafenberg
14473 Potsdam
Germany
Academic Training
1999: Ph.D., Seismology, Freie Universität Berlin
1989: M.Sc., Seismology, Institute of Geophysics, Chinese Academy of Sciences
1986: B.Sc., Geophysics, University of Science and Technology of China
Professional Experience
2003-present: Staff scientist, GFZ
2000-2003: Postdoc, GFZ
1996-1999: PhD student, GFZ
1994-1995: DAAD Scholar, Universität Kiel
1989-1994: Research assistant, Institute of Geophysics, Chinese Academy of Sciences, Beijing |