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1980 eruption of Mount St. Helens

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Footage of the 1980 Mount St. Helens Eruption

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Mt. St. Helens Eruption May 18, 1980 720p HD

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Best Video of Mount St Helens Volcano Eruption footage

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Volcano Eruption Power Comparison

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Mount St Helens, May 18, 1980

On May 18, 1980, a major volcanic eruption occurred at Mount St. Helens, a volcano located in Skamania County, in the State of Washington. The eruption was the most significant volcanic eruption to occur in the contiguous 48 U.S. states since the much smaller 1915 eruption of Lassen Peak in California. It has often been declared as the most disastrous volcanic eruption in U.S. history. The eruption was preceded by a two-month series of earthquakes and steam-venting episodes, caused by an injection of magma at shallow depth below the volcano that created a large bulge and a fracture system on the mountain's north slope.