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Full‐wave multiscale anisotropy tomography in Southern California
Author(s) -
Lin YuPin,
Zhao Li,
Hung ShuHuei
Publication year - 2014
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2014gl061855
Subject(s) - geology , anisotropy , lithosphere , seismic anisotropy , shear wave splitting , asthenosphere , mantle (geology) , geophysics , wavelength , spatial variability , seismology , tectonics , physics , optics , statistics , mathematics
Understanding the spatial variation of anisotropy in the upper mantle is important for characterizing the lithospheric deformation and mantle flow dynamics. In this study, we apply a full‐wave approach to image the upper‐mantle anisotropy in Southern California using 5954 SKS splitting data. Three‐dimensional sensitivity kernels combined with a wavelet‐based model parameterization are adopted in a multiscale inversion. Spatial resolution lengths are estimated based on a statistical resolution matrix approach, showing a finest resolution length of ~25 km in regions with densely distributed stations. The anisotropic model displays structural fabric in relation to surface geologic features such as the Salton Trough, the Transverse Ranges, and the San Andreas Fault. The depth variation of anisotropy does not suggest a lithosphere‐asthenosphere decoupling. At long wavelengths, the fast directions of anisotropy are aligned with the absolute plate motion inside the Pacific and North American plates.