Shear wave splitting analysis is one of the most commonly used techniques in structural seismology. In this study, the splitting parameters of Moho converted P-to-S phase (Pms), the time difference between maximal energy of qS1 and qS2 and their amplitude ratio were obtained. The data were from 29 broad-band stations across the Longmenshan fault belt. Subsequently, the deformation features of the crustal structure beneath the east Tibetan margin and Sichuan basin were analyzed. Our results show that the time delay and the time difference between maximal energy of qS1 and qS2 in east Tibetan margin is obviously larger than Sichuan basin. However, the amplitude ratio between qS1 and qS2 beneath Longmenshan fault is much smaller than other tectonic sub-regions. These results may suggest the existence of fluid beneath the Longmenshan fault.
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