Surface wave dispersion across Tibet: Direct evidence for radial anisotropy in the crust

被引：36

作者：

Duret, F. ^{[1
]}

Shapiro, N. M. ^{[1
]}

Cao, Z. ^{[2
]}

Levin, V. ^{[3
]}

Molnar, P. ^{[4
]}

Roecker, S. ^{[5
]}

机构：

[1] Univ Paris Diderot, Sismol Lab, UMR 7154, Inst Phys Globe Paris,CNRS, F-75252 Paris 05, France

[2] China Earthquake Adm, Tibetan Bur, Lhasa 850000, Peoples R China

[3] Rutgers State Univ, Dept Earth & Planetary Sci, Wright Geol Lab, Piscataway, NJ 08854 USA

[4] Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA

[5] Rensselaer Polytech Inst, Dept Earth & Environm Sci, Troy, NY 12180 USA

来源：

GEOPHYSICAL RESEARCH LETTERS | 2010年 / 37卷

基金：

欧洲研究理事会; 美国国家科学基金会;

关键词：

ASIA COLLISION ZONE; SOUTHERN TIBET; UPPER-MANTLE; SEISMIC ANISOTROPY; CONTINENTAL DEFORMATION; FINITE STRAIN; FLOW; EXTENSION; PLATEAU; BENEATH;

D O I：

10.1029/2010GL043811

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Recordings in western Tibet of Rayleigh and Love waves at periods less than 70 s from aftershocks of the 2008 Sichuan earthquake cannot be matched by an isotropic velocity model beneath Tibet. These intermediate-period Rayleigh and Love waves require marked radial anisotropy in the middle crust of Tibet, with the vertically polarized Swaves propagating more slowly than S-waves with horizontal polarization. The magnitude of anisotropy inferred using paths entirely within Tibet is slightly greater than that obtained previously from a tomographic inversion of a dataset covering a larger region. Anisotropy in the middle crust likely reflects deformation of the middle crust, and is consistent with the notion of mid-crustal flow and thinning of the crust. Citation: Duret, F., N. M. Shapiro, Z. Cao, V. Levin, P. Molnar, and S. Roecker (2010), Surface wave dispersion across Tibet: Direct evidence for radial anisotropy in the crust, Geophys. Res. Lett., 37, L16306, doi:10.1029/2010GL043811.

引用

页数：5

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