Crustal deformation state shown by fault measurement and GPS

In Capital area of China, many fault deformational surveying sites were set up sequentially from 1967. With short leveling, short base line and short ranging net across fault, a lot of data have been accumulated. In 1992, GPS (Global Positioning System) measurements were started in China. Two times of GPS measurements have been made in 1992 and 1995 respectively. The Inter national Terrestrial Reference Frame 93 and the Precision Ephemeris provide d by International GPS Geodynamics Service (IGS) from Global GPS tracing ne twork solution are used. In GPS analysis and data processing, GAMIT softwar e and GLOBK software are used. The results from these two kinds of data are discussed. For earthquake risk area judgment, it is of interest to know wh ere is compressional area and where is tensional area, and generally the co mpressional areas are considered as risk area and called abnormal area. All the data from short leveling, short ranging (measured by laser-range-finde r), short base line (measured by base line tape) and GPS methods can give u s the description about the deformational state of the crust - compressiona l state or tensional state. The comparison shows that, some of the two kind s of data are consistent, a few of them are contradictory, and then the res ults are discussed.