From Earth Science Picture Of The Day; July 2, 2014:
Photographer:& Robert Farrimond; Summary Authors: Robert Farrimond, Jackie Phillips
The photo above shows the scarp left behind from the Bonneville landslide. Following recent landslides& that occurred in the region, I remembered seeing this scar on the mountainside near Bonneville Dam between Washington and Oregon. There have been four notable slides in this field. The most recent is named the Bonneville Slide. It’s believed that it created an earthen dam, impounding the river until it washed over and destroyed the dam releasing a 100 ft (30 m) high flood. While the actual date the Bonneville Slide occurred is still disputed, Lewis and Clark noted the slide debris and tree stumps protruding from the water in 1805. The view is looking across the Columbia River from Oregon near Cascade Locks. Photo taken on June 1, 2014.