酒泉盆地北侧金塔南山北缘断裂西段全新世活动特征

Active Faulting Features in Holocene of the West Segment of the Jintananshan North-margin Fault at the North of Jiuquan Basin

金塔南山北缘断裂是酒泉盆地北侧的一条重要的活动断裂,断裂西起梧桐墩西北,向东经长山、瓜勾山、鸳鸯池水库、大口子山到红墩以西,长约60km,走向近东西,倾向北或南,倾角60°～80°。断裂活动方式以挤压逆冲为主,兼有左旋走滑特征。通过对现场断错地貌的调查和探槽开挖,发现金塔南山北缘断裂西段晚第四纪活动强烈,并有古地震发生。

Jintananshan north-margin fault is an important active fault at the north of Jiuquan Basin.The fault starts from the northwest of Wutongdun in the west,then passes through Changshan,Guagoushan,Yuanyangchishuiku,Dakouzi,and ends in the east of Hongdun.The main trending is near EW with length 60 km,dip is south or north,and the dip angle is 60~80 degree.The active manner of the fault is mainly thrust with left-lateral strike-slip features.According to field geomorphic investigation and trench excavation,we found strong active evidence at the west segment of the Jintananshan north-margin fault.Paleo-earthquakes have also be found there.