Occasionally, glaciers move downslope very quickly during short-lived events called surges. Surges can move the ice at velocities up to 100 times faster than normal (e. g., 5–7 km/yr. or 4.5–7.5 miles/yr. or 10s m/day). Surge events are causes by large scale basal melting that lubricates the entire base of the glacier and facilitating sliding like a slip and slide. Examine the glacial movements.