 Geologic evidence supports the view that the slide occurred 13,000 to 15,000 years ago as the result of undercutting which occurred during the Missoula Floods associated with the retreat of glaciers during the last ice age.Water flowing through the Channeled Scablands split into two streams just upstream of the Corfu Slide, with part flowing to the east to pass over the low end of the Saddle Mountains and part flowing westward to pass through Sentinel Gap in the Saddle Mountains.The force of the water diverted to the west impinged on the base of the Corfu Slide area, causing erosion.