| This paper mainly focuses on the geometry and kinematics of Mesozoic ThrustSystem. The author also has a research on the history of regional structural evolution andthe mutual relationship among Thrust, Intrusion and Extensional activities. Several piecesof new achievements and fresh ideas have been arrived as follows:1,In this region , the Thrust System is composed of HYSTH (western segment );JMSTH;BBSTH (eastern segment), which constitute the structural framework ofMesozoic Thrust System. Thrusting direction of this system is from southeast to northwestjudging by some characteristics of secondary faults and the associated structures (scratchlineation). Formed in contractive stress field, the nappe belongs to Thrust-Nappe type andits growth is similar to Propagation-folding model .2,From west to east , the linear fault plane on the ground characteristically displays achange of strike from NE to EW (approximate). It is a result of synchronous deformationduring the process of thrusting stage but not due to followed structural activities after theprocess of thrusting stage. Basement-structure and Pre-structure in the deformationalterrain take a control on the segmentation of Thrust System in this area.3,The combination of basement-involved thick-skinned structures (eastern segment)and only cover sequence-involved thin-skinned structures (western segment) is a peculiarcharacter of Thrust System in this district .Our balanced cross-sections indicate thathorizontal shortening rate of western segment is 23.7% but the eastern is 29.5-36%, largerthan the western segment, which corresponds to the regional structure.4,Integrated with the isotope-dating data of different researchers, the rough thrustingage should be during 140～130 Ma according to the result of intrusive geochronology andthe relationship between the structural deformation and intrusive rocks. Compared with anew geologic times scale provided by ICS, 2004, the geologic age of thrusting activityshould be Early Cretaceous.
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