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Mount St. Helens and its famous 1980 eruption


I know I don't usually write a lot on this site, but I just had to write something about Mount St. Helens as it is such a majestically beautiful volcano with so much history. Mount St. Helens is located in Skamania County, Washington and is an active stratovolcano. It takes its name from Lord St Helens, the British diplomat who made a survey of the area in the late 18th century. This volcano is part of Pacific Ring of Fire, which includes over 160 active volcanoes.

The event that most people will remember Mount St. Helens for is its 1980 eruption. Those who survived the disaster will still remember it today as it was a very dramatic event. This eruption was huge and was the most economically destructive volcanic event ever to occur in the United States. 57 people died and 250 homes were destroyed, along with 185 miles of highway. The eruption also obliterated 47 bridges and 15 miles of railways. It was extremely dramatic and has firmly made an imprint on history.

An earthquake measuring 5.1 on the Richter scale triggered a huge avalanche of debris, and then the eruption. The earthquake was brought about by a sudden surge of magma from the mantle of the Earth and the crater left by the eruption measures one mile wide. The summit of the mountain was also reduced from 9,677 ft to 8,365 ft. This was a drastic change as Mount St. Helens used to be the fifth-highest peak in Washington. The mountain itself is made up of lava rock that is interlayered with ash and pumice, as well as other deposits. It is an eruptive cone that is layered with basalt and andesite, which several domes of dacite have erupted through. This volcano is amazing to see and is a very famous landmark that is steeped in a violent history.