On the morning of May 18, 1980, an earthquake shook Mt. St. Helens and the mountain's north face collapsed in one of the largest debris avalanches ever recorded.
The slide uncorked the volcano, baring magma that exploded with 500 times the force of the Hiroshima bomb in the most destructive eruption in U.S. history.
The cataclysmic chain of events killed 57 people and thousands of animals, took out 250 homes, 47 bridges and 185 miles of highway, clogged rivers with sediment, flooded valleys and blocked the Columbia River shipping channel.
Forty years later, the destruction may not be over.
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USGS needs a force-designation for volcanic eruptions, like NOAA has for hurricanes and tornadoes. Since volcano stories reference comparison to the Hiroshima bomb, a USGS designation for the Mount St. Helens blast would be 500H. How anybody actually measures the H factor is never explained, nor is why stories don't do a volcano-Nagasaki comparison. Either one, H factor or N factor. Hiroshima gets all the coverage, poor Nagasaki is the Rodney Dangerfield of blasted into oblivion cities, it don't get no respect.
ReplyDeleteI was on a Submarine in the yards @ bummertown (Bremerton) and lived in barracks in the new base in Kings Bay when that happened. Made a mess in KB with 3 inches of ash all over.It was crazy time in the ship yard too!
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