三峡库区巫山县新城址巴东组三段形成的大型复杂滑坡特征及成因机制

巫山县新城址巴东组三段泥质灰岩在地质历史上已全部发生了滑坡，滑坡体可分为上、中、下三段，滑坡的发育经历了（1）印支期和燕山期构造；（2）新构造上升、长江切割引起岩体松动卸荷及岩溶作用；（3）巴东组三段沿二段顶部泥化层滑动；（4）中部陡坡带形成，滑坡分解；（5）上、下两段滑坡格局形成；（6）上段滑坡进一步分离形成中段滑坡；（7）后期溶蚀、风化。滑坡的后期改造过程仍在继续。

Features and Genesis of Large Complex Landslide Developed from 3rd Member of Badong Formation in the Newly Built Wushan County Seat, Three Gorges Reservoir Region

The whole argillaceous limestone of 3rd Member of Middle Triassic Badong formation (called T2b3 for short)in the newly built Wushan County seat has slid along the argillated top of T2b2 calcareous mudstone in geohistory.The landslide can be divided into upper,middle and lower sectors.It was brought about by the processes of ①tectonic fracturing;②neotectonic uplifting,rock mass loosening with the stress release led by the Yangtze River cutting,and karst dissolution;③the whole T2b3 sliding along the T2b2 argillated top;④the formation of the middle steep slope and the fracturing of the landslide;⑤the formation of the framework of the upper and lower sectors of landslide;⑥the development of the middle sector in the front part of the upper sector;⑦the further dissolution and weathering,which is still going on now.