Abstract
Southeast Tibet, a key region for the southeastward extrusion of the Tibetan Plateau, remains debated in terms of its tectonic deformation in response to the ongoing collision between the Indian and Eurasian plates. In this study, we applied shear-wave splitting analysis of core-refracted phases recorded by a newly deployed dense seismic array and six permanent stations to delineate crustal and mantle deformation processes. The observed fast polarization directions are predominantly aligned NNW–SSE, while the splitting delay times vary across four sub-blocks. The anisotropy pattern suggests a dominantly asthenospheric origin, consistent with southeastward-directed mantle flow associated with the extrusion of the Tibetan lithosphere. The splitting delay times are relatively larger near major faults and tectonic boundaries compared to areas farther away, and the fast polarization directions beneath these structures exhibit a moderate rotation toward the fault strike, indicating that such tectonic discontinuities contribute to observable azimuthal anisotropy.
Recommended Citation
J. Wu and Y. Ai and S. S. Gao and P. Huang and F. Kong and D. Xu and J. Song and X. Gao and M. Wei and L. Li and J. Zhang and Y. Zhang and Y. Zhang, "Mantle Flow and Fault Zone Related Seismic Anisotropy Revealed by a Dense Linear Broadband Array in Southeast Tibet," Geophysical Research Letters, vol. 52, no. 16, article no. e2025GL116054, Wiley; American Geophysical Union, Aug 2025.
The definitive version is available at https://doi.org/10.1029/2025GL116054
Department(s)
Geosciences and Geological and Petroleum Engineering
Publication Status
Open Access
Keywords and Phrases
broadband array; fault zone; seismic anisotropy; shear-wave splitting; southeast Tibet
International Standard Serial Number (ISSN)
1944-8007; 0094-8276
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2025 Wiley; American Geophysical Union, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
28 Aug 2025
Comments
Stanford University, Grant YSBR‐082