王峪口水库库岸滑坡特征及形成机制

王峪口水库库岸滑坡地层主要为一套上新统砾石层、夹砂层、粘土层．区内滑坡具有明显的分期性与群发性特点．滑坡形成的主要原因是该套地层夹有饱水软化的粘土层和易于液化的饱水砂层；地震则可能是其触发因素．

A STUDY OF LANDSLIDES AROUND THE BANK OF THE WANGYUKOU RESERVOIR

The landslides around the Wangyukou reservoir developed in Pliocene series comprised of gravel beds with some grayish white sand beds and brown red clay band.Nearly all the landslides slided along the lower saturation clay beds,especially sandbeds.The landslides have its own shapes,various sliding patterns and different scales.The conspicuous characteritics of distribution and occurrence of the landslides in this area is substage and swarm.Based on the features of combination structure and surface form,the landslides are divided into three stages.The landslides of the first stage have no visible fissure on the rounded slide mass with well developed vegetal cover,and its slide pattern dominated retrogressive type.The landslides in the second stage have visible fissures on the slide mass with developing vegetal cover,and slide pattern dominated slumped tpye.The majority of the third stage landslides with small scale and simple sliding plane mainly distributed along frontal and lateral border of the first and second landslides.The sand beds and clay beds in the strata were main conditions of sliding,and the landslides are infered from their structrual features and distributing regularity to earthquake induced ones.