Mount St. Helens May 18, 1980 eruption
Credit: USGS Photograph taken on May 18, 1980, by Robert Krimmel.
The eruption of May 18, 1980 sent volcanic ash, steam, water, and debris to a height of 60,000 feet. The mountain lost 1,300 feet of altitude and about 2/3 of a cubic mile of material stream downward from the center of the plume and the formation and movement of pyroclastic flows down the left flank of the volcano.
