三峡水库蓄水后对库区岸坡地貌过程的影响

长江三峡水库蓄水后,因库区水位周期性涨落,引起水动力条件明显改变,导致地下水和库水共同作用于岸坡表面和岩土介质,对岩土体产生物理、化学和力学作用,对松散堆积物岸坡和基岩岸坡产生不同的影响,地貌动力作用由在基岩风化剥蚀基础上以重力作用为主变为在库水和地下水作用下以蠕动、滑移、崩塌、侵蚀、冲蚀作用等为主,进而引起岸坡变形,使岸坡地貌过程发生一系列变化,岸坡将经历一个地貌改造一再造的长期过程。

Influence of the Three-Gorges Reservoir on Geomorphic Process on Bank Slope of the Yangtze River

After the completion of the Three Gorges reservoir,a series of changes in fluvial geomorphology process- es will inevitably occur on bank slope of the reservoir.Two parallel permanent fluctuating belts will form on bank slope,and thus the power of reservoir water will fluctuate with changed water level.Changes in groundwater and reservoir water may affect bank slope surface and rock medium.The changes have physical,chemical and mechan- ics effects on rock materials,and influence loose deposits and rocky bank slope,differently.The major geomorphic processes may shift from gravitational geomorphic processes to creep,slide,collapse,erosion and washing process- es,which transforms bank slope in turn.The geomorphic transformation and re-transformation processes on bank slope will last for a long time.