Off_great circle propagation of Love waves in eastern Qinghai_Xizang Plateau
青藏高原东部Love波偏振研究

The data of three-component digital surface wave from 50 portable seismograph stations located in west Yunnan, China, were collected and analyzed in this study. A frequency domain singular value decomposition method was used for polarization analysis ; and the polarizations of intermediate period Love waves traveling through the Qinghai-Xizang Plateau were calculated and evaluated. The result shows that there are obvious polarization anomalies, which could be due to the lateral heterogeneity of the lower crust and uppermost mantle velocity structure in the wave propagation path. Besides, theoretical arrival azimuths were computed by using the velocity model from a previous tomographic study. There is general consistency between the theoretical result and the majority of the observations, though the theoretical anomalies are often smaller than the observations. The result of present study indicates the correctness of our velocity model, as well as the complexity of the lithosphere in this area which is not fully reflected in the model.