Mount St. Helens 1980 eruption devastation
Credit: USGS Photograph taken on August 22, 1980, by Lyn Topinka
For weeks volcanic ash covered the landscape around the volcano and for several hundred miles downwind to the east. Noticeable ash fell in 11 states. The total volume of ash (before its compaction by rainfall) was approximately 0.26 cubic mile, or enough ash to cover a football field to a depth of 150 miles.
