关键词: 汾渭地震构造带, 活动断裂, 断层位移速率, 断层分段

Abstract:

Based on the geological and geomorphological research of geometric distribution,segmentation and segment boundaries of the northern piedmont fault of Liuleng Mountain,we suggest thatthis active fault can be divided into four segments.The eastern segment is considered to be theearly Pleistocene active fault and the other three segments to the late Pleistocene-Holocene activefaults. The length of the segments is 10～39 km. This fault was a thrust fault in the late Mesozoic,but in the Cenozoic it turned into normal fault due to the change of regional stress field.The vertical displacement on each segment is characterized by enveloping curve,with its unequalaverage vertical slip rate. The rate is high in the west and gradually decreases from west to east,suggesting a difference of the activity along the fault.

Key words: Fen-Wei seismotectonic zone, Active fault, Fault displacement rate, Fault segmentatlon