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Fun Fact May 18, 2020.

18 May 2020


The landscape in the Pacific Northwest changed on this date in 1980.  Forty years ago Mount St. Helens, a stratovolcano located in Skamania County in Washington state, erupted.  The eruption was the deadliest and most economically destructive volcanic event in U.S. history. Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles of railways, and 185 miles of highway were destroyed. There was a massive avalanche of debris triggered by a magnitude 5.1 earthquake.  That earthquake triggered a lateral eruption that took the mountain from an elevation just under ten thousand feet to just over eight thousand feet, leaving a 1 mile wide horseshoe-shaped crater. The debris avalanche was up to three quarters of a cubic miles in volume. The Mount St. Helens National Volcanic Monument was created to preserve the volcano and allow for the eruption’s aftermath to be scientifically studied.