Abstract:According to the theory of surface deformation caused by the dislocation on a rectangular fault within an isotropic homogeneous halfspace, the characteristics of surface deformation caused by one fault or combination of two faults are studied. The main conclusion are as follows: 1) For one fault, the characteristics of surface deformation and the pattern of dislocation is closely related. The depth of fault, the dip angle and the magnitude of dislocation(U1,U2,U3) have grate effects on the deformation as well. 2) For the combination of two faults, when they are in the same depth, the relative position of the faults have great effect on the surface deformation; when they are in different depth, the shallow fault plays a dominant role in the total surface deformation.