Abstract：Taking an example of an bank slope in Jiudian Gorge reservoir,the stability of ancient reservoir bank slope in early reservoir impoundment is studied. The displacement is used to preciously and continuously monitor by GPS,and the deformation characteristic of the slope was analyzed in combination with engineering geological conditions. The Geo-slope was used to calculate the stability of slope with rate of water level rise.The result shows that the stability of bank slope is stable on the whole,and the stability of landslide decreases with the water rising rate increasing,which the local instability will occour when it is more than 0. 5 m / d; the displacement of the middle part of the slope was the largest,the displacement velocity trended to become smaller generally; the displacement deformation model was creep damage characteristics which was the central block pull the leading edge. The stability of ancient landslide is stable generally,but the local slide occur.The analysis rule used by Geo-slope is in accordance with the law used by analyzing GPS data,which verifies that the monitoring data is reliable.

Keyword：reservisir reservoir rise;bank slope;stability;GPS monitoring;ancient candrcite;