| Abstract: | This paper discusses the velocity structure of the crust (P-wave) and the upper mantle (S-wave)along the region of the Manzhouli-Suifenhe Geotransect, which has been obtained from the data of seismic sounding and surface wave dispersion. The results indicate that the Geotransect may be separated into three velocity blocks of Erguna-Daxinganling, Songliao-Zhangguangcailing and Jiamusi-Xingkai. The crust of the Geotransect is divided into three layers by P-wave velocity and its thickness is 29-38 km. The mean P-wave velocity of the crust is 6.32 km/s. Low velocity layer of upper mantle differs greatly in depth in the traverse. The low velocity layer of upper mantle of the Songliao basin is the shallowest. Shallow shocks are relatively few and weak and the foci lie in the middle and upper crust, and deep focus earthquakes are fairly frequent and strong with the foci located at depths of 400-600 km. |
