Crustal structure of China mainland and its adjacent regions

According to the three-components teleseismic records from digital seismic station network of the China mainland and its adjacent regions, the S-wave velocity structure beneath 61 teleseismic stations are investigated by using the transform function method and the SA technique. Based on the results of our work and the information from artificial seismic sounding, this paper presents Moho topography beneath the of China mainland and its adjacent regions, which is credible geophysics evidence for geodynamic evolution processes and the continental dynamics theory. The result shows that, the crustal thickness of the China mainland and its adjacent regions increase from east to west, and the crustal structure can be divided into there types, including the gentle variation region such as Mongolia plateau, North China, Central China, South China and Qinghai-Tibet plateau; the transitional region such as regions along Great Xing' an Mountains, Taihang Mountains, Qingling Mountains, Dabie Mountains and Yungui plateau; and the gradient belt such as the Qinghai-Tibet plateau periphery. Below the gentle variation regions, simple S wave velocity structure and clear crustal-mantle boundary are revealed except for the Qinghai-Tibet plateau. The S wave velocity structure beneath regions along Taiwan-Philippine Islands, the Qinghai-Tibet plateau and its south flank are complex. It indicates that tectonic movement and substance exchange are active in the plate boundary regions where the crust remains in the state of imbalance.