Abstract: The NNW-trending linear traces in the Shizhikou area of the Three Gorges section of Changjiang River reflect the relief,lithologic features and small-scale faults. It is inferred from geologic and geomorphic data and result of isotopic dating that the Qinglin-kou fault was slightly activated in 49?10⁴a B. P. The Jufang fault was not activated since 50?10⁴a,and other three small faults were not been also activated since 50?104a,even in the Quaternary period. The geologic and geomorphic data and distribution of earthquake epicenters indicate that the NNW-trending faults in the studied area have not been active in recent time,and not the seismogenic and earthquake-generating faults either which would not have an influnce on the stability of the Three Gorge reservoir and its dam.

Key words: Three Gorges on Changjiang River, Sizhikou area, Recent fault activity, Enginering-active fault

摘要： 经野外调查和验证,长江三峡狮子口地区的NNW向遥感线性形迹是地形、岩性和小型断层的反映。对区内断层带样品进行的同位素年龄测定,判定出青林口断层在距今49×10⁴a曾有轻微活动,其余的四条断层第四纪(240×10⁴a)以来无活动。地貌、地质和微震(M<3)分布表明,这些断层现代是不活动的,非控震构造,对三峡水库、大坝工程稳定性无影响。

关键词: 长江三峡, 狮子口地区, 断层最新活动, 工程活动断裂