Crustal fabric in the Tibetan Plateau based on waveform inversions for seismic anisotropy parameters

Heather Folsom Sherrington, George Zandt, Andrew Frederiksen

Research output: Contribution to journalArticle

123 Citations (Scopus)

Abstract

The Tibetan Plateau has the thickest continental crust on Earth, and fabrics within the crust that are anisotropic to seismic waves may provide clues to how it reached such extreme proportions and how it is currently deforming. Waveform modeling using a global minimization inversion technique applied to receiver functions computed from 11 stations spanning.the north-south length of the eastern plateau has yielded a suite of crustal models that include anisotropy. These models suggest that the Tibetan crust contains 4-14% anisotropy at different depths that is likely a result of both fossil fabrics and more recent deformation. All models contain anisotropy in the surface layer, and for most stations the alignment of the slow symmetry axis suggests a relationship with crustal fabrics asociated with E-W trending thrust faults or sutures. Middle to lower crustal anisotropy is present at most stations with a fast axis trending N-S to NW-SE in the south, nearly E-W in the central plateau, and N-S to NE-SW in the northern plateau. This pattern appears consistent with recent ductile deformation due to both topographically induced flow and to boundary forces from subducting lithosphere at the northern and southern margins of the plateau. The orientations of crustal anisotropy determined for most stations in this study are significantly different from shear wave splitting fast polarization directions, implying distinct deformation in the crust and mantle.

Original languageEnglish (US)
JournalJournal of Geophysical Research: Space Physics
Volume109
Issue number2
StatePublished - Feb 10 2004

Fingerprint

seismic anisotropy
plateaus
waveforms
Anisotropy
anisotropy
plateau
inversions
crusts
stations
crust
Seismic waves
wave splitting
ductile deformation
Shear waves
seismic waves
fossils
thrust fault
lithosphere
seismic wave
continental crust

Keywords

  • Anisotropy
  • Crust
  • Inversion
  • Modeling
  • Seismology
  • Tibetan Plateau

ASJC Scopus subject areas

  • Oceanography
  • Astronomy and Astrophysics
  • Atmospheric Science
  • Space and Planetary Science
  • Earth and Planetary Sciences (miscellaneous)
  • Geophysics
  • Geochemistry and Petrology

Cite this

Crustal fabric in the Tibetan Plateau based on waveform inversions for seismic anisotropy parameters. / Sherrington, Heather Folsom; Zandt, George; Frederiksen, Andrew.

In: Journal of Geophysical Research: Space Physics, Vol. 109, No. 2, 10.02.2004.

Research output: Contribution to journalArticle

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