Many NW-trending faults are developed in West Shandong.Cangshan-Nishan Fault,about 130km long,striking 310° ~ 340°,dipping to SW and NE with dip angle 70° ~80°,is the largest one among these faults.According to geomorphological characteristics and relationship between fault and Quaternary deposits,Cangshan-Nishan Fault can be divided into three segments:the western segment (Fangshan-Tianhuang segment),about 30km long,controlling the western margin of Qufu Basin; the middle segment in the bedrock area (Tianhuang-Ganlin segment),about 80km long,forming a valley and controlling evolution of Baiyan River; and the eastern segment (Ganlin-Cangshan segment),buried in the Quaternary basin,about 20km long.The western segment (Fangshan-Tianhuang segment)appears as a linear scarp in the satellite images.Field investigation shows that the linear scarp is mainly composed of rock with 2 ~5m high in topography.On the northeast side of the scarp is mountains composed of Archaeozoic Taishan group gneiss,and on the south-west side is late Pleistocene alluvial fan.A lot of profiles reveal that the latePleistocene deposits (the thermoluminescence dating results)are dislocated by the fault.The fault cross sections near the Qufu city show it is a normal fault with high scarps.The highest scarp is 4.7m high and the normal vertical slip rate is 0.07mm/a.However,the fault cross sections near the Tianhuang Town show it is a reverse fault with high dip angle.The highest scarp is about 1.5m high,lower than that near the Qufu city.All these information indicate that the fault,from west to east,is changed gradually from normal feature to reverse feature,and the height of fault scarp is decreased gradually from west to east.Based on reported results in this area,Cangshan-Nishan Fault is a left-lateral strike-slip hinge fault.The results presented in this paper suggest that the western segment is dominated by normal dipslip with left-lateral strike-slip component,the middle segment is dominated by left-lateral strike-slip with reverse dip-slip component.As the axes of hinge fault,the middle segment is the most active segment of Cangshan-Nishan Fault.Besides Cangshan-Nishan Fault,a series of NW-trending faults are developed in West Shandong with weak activity since late-Pleistocene.Many moderate-strong earthquakes are related to these NW-trending faults.We thus think these NW-trending faults have capability of generating moderate-sized quakes.