Abstract: Great earthquakes often occur along active fault belts or near by, thus, the monitoring and researches on fault deformation is quite important. Short leveling, short base-line, and integrated monitoring across fault belts etc. have been used to monitor fault activities for many years. GNSS data are mainly used to study horizontal movements in large areas and crust block activity. In this paper, some applicationsand new explorations of GNSS for researches on fault deformation are introduced and discussed as follows: (1) Monitoring and study on horizontal sliding of fault with GNSS; (2) Monitoring and study on vertical movement of fault with GNSS; (3) By studying the orderliness of crust block deformation on both sides of the fault and setting up models of blockmovement and strain, the fault's deformation can be deduced from the models, and then the comparison between the deduced deformation and that monitored directly across faults can be done. Our study shows that the larger the differences of deformation between them,the stronger theaction has between two blocks. This will be very important for prediction of earthquake location and seismic risk estimation.

Key words: GNSS, Crust deformation, Leveling, Seismicity, Crust block