A New Body-Wave Amplitude Ratio-Based Method for Imaging Shallow Crustal Structure and Its Application in the Sichuan Basin, Southwestern China
A New Body-Wave Amplitude Ratio-Based Method for Imaging Shallow Crustal Structure and Its Application in the Sichuan Basin, Southwestern China
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DOI：
10.1029/2021gl095186
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Huajian Yao
中科院分区：
文献类型：
--
作者：
Xu Wang;Ling Chen;Huajian Yao
Shallow crustal velocity and Poisson's ratio structures are of key importance to understand rock properties and near-surface tectonic deformation and evolution. We propose a novel imaging method to acquire such information at individual stations by joint inversion of amplitude ratios between the horizontal and vertical components of both teleseismic P and S waves. Our synthetic experiments demonstrate the validity of the method in recovering subsurface structures up to ∼8–10 km depth. We apply this method to construct the velocity and Poisson's ratio images along a NW-SE-trending seismic array within the Sichuan Basin, southwestern China. The results reveal well developed stratification and localized high Poisson's ratio anomalies, which reflect a long-term stable sedimentary environment and fault-related deformation in response to the Cenozoic Tibet–basin collision, consistent with geological observations. Our new method builds a bridge between fine-scale near-surface seismic exploration and large-scale deep passive-source imaging, especially for areas of weak seismicity.
