Abstract: In this paper, amethod to synthesize different GPS networks has been proposed, and by usi ng this method, synthesis of 4 high-preci sion GPS networks in China's continent have been realized. The velocity fi eld of horizontal movement and the contour map of N and E-t rending component fields in China's continent and the surrounding areas have obtained. Under the global frame, China's continent and the surrounding areas have an obvious eastward mov ement. The directions of N S-trending movements are oppo site in the western and eastern part of China's continent. The eastern part of Xizang plateau is the area with the most intensive crustal movement in China's co ntinent. The direction of horizontal movement in China's continent likes a beam of radial arc lines with the same o rig in. Based on the characteristics of horizontal crustal movement in China's continent, the geodynamic environment around China's continent has been analyzed, and a rough estimation has been made for the magnitude of acting forces from each plate and block to China's co ntinent. According to the estimation, the impact force from India plate to China's continent is the maximum, and then is the underthrusting force from Philippi ne Sea plate to China's continent.

Key words: Synthesis of GPS networks, Velocity field of China's continent;, Geodynamic environment