关键词: 则木河断裂, 地震地貌, 古地震事件

Abstract: Earthquake-caused landforms are the indicators of earthquake ruptures on the surface. Therefore the microgeomorphical analysis is an effective method in paleoseismic study. Through the study of newly found earthquake-related landforms (including fault scarps, offset gullies, wavy lands, and slopehanging-ditches) at Daqingliangzi, Xichang,Sichuan Province, at least four (may be seven) paleoseismic events of magnitude greater than 7 were identified. This result shows that strong earthquakes have occurred repetitively at the same place on the northern segment of the Zemuhe fault since later Pleistocene. Tne minimum time interval between every two strong earthquakes, on the northern segment of the Zemuhe fault is about 1000a during the Holocene-period, and the average time interval is about 1800a.

Key words: Zemuhe fault, Earthquake-related landform, Paleoseismic event