Twenty-one years later, Mount St. Helens still offers lessons

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Abstract

Mount St. Helens National Volcanic Monument, Washington State, October 18—During the drive up to Mount St. Helens on a brisk, clear, fall day, Christine Colasurdo noted that this region of the country has been shaped by volcanism.

“This is a place where the soils have dropped from the sky” said Colasurdo. Her family had enjoyed a cabin along the mountain's Spirit Lake prior to a series of volcanic events that began in 1980—including earthquake-triggered landslides, a lateral cataclysmic eruption, a vertical column of ash, and lahars and pyroclastic flows on May 18,1980. Events of that day alone lowered the 2,932-meter-high volcano by 398 meters, as 2.8 billion cubic meters of material removed from the mountain flattened 148,000 hectares of forest, killed 57 people, and completely changed the landscape. Ash from the volcano circled the Earth in 15 days.

Ancillary