Based on the polarization analysis of teleseismic SKS waveform data recorded at 90 broadband stations in the Ordos block and adjacent regions, the splitting parameters of fast polarization direction and delay time between the fast and slow shear waves are determined for each station using the minimum transverse energy method, yielding the images of upper mantle anisotropy. Combined with the GPS horizontal velocity field with respect to the Ordos block during 1999~2007, we analyze the seismic anisotropy as well as the crust‐mantle coupling beneath the Ordos block and its adjacent regions. At last, a new understanding of the block movement and the dynamic causes of the adjacent fault zones is achieved. The results reveal that there are nulls in the block which show an obvious isotropic characteristic. The delay time of the adjacent stations is obviously greater than those in the central block, which indicates an obvious anisotropy. The fast polarization directions are compatible with the tectonic strike direction and the horizontal velocity direction, which shows the crust‐mantle coupling. The differences between the directions at some stations may be associated with the early block activities. According to the SKS shear wave splitting results and the current GPS velocity field, we suggest that the Ordos block has no rotation. Meanwhile, the horizontal and ascending intrusion and the transverse extension of the plastic material in the upper mantle lead to the bifurcated flow around the Liupan Shan Mountains in the southwestern margin of Ordos. The generation and development of the Fenwei graben are the result from upward intrusion and lateral spreading of upper mantle material along deep faults.

Making use of GPS observational data in area of the northeast margin of Qinghai–Xizang block in the years 1993 and 1999, the distribution figures of velocity field and apparent strain field of crustal horizointal movement of this area are given, and the method of directly solving the parameters of block rotation and deformation from displacement observation is presented, so the characteristics of tectonic block motion and deformation in this area are studied preliminarily. The results show that: (1) This area shows a whole motion toward east‐southeast (whose velocity is about 9mm/a); (2) Gunsu–Qinghai block in the south of this area moves faster, but Alashan block in the north of this area moves slower, the difference of motion velocity between two blocks is near 6 mm/a, the sinistral strike slip movement of Qilian–Haiyuan fracture zone is remarkable; (3) There exists NNE‐NEE compressional movement from west to east; (4) Inside Alashan block and Gansu–Qinghai block, there are NWW tensional deformations, the whole tensional deformation of Alashan block is even more obvious, moverover, in the meeting region of blocks in the west side of Ordos block, compressional movement is relatively remarkable.

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