Mount St. Helens National Volcanic Monument, WA

· United States Washington
Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 1Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 2Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 3Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 4Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 5Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 6Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 7Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 8Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 9Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 10Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 11Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 12Mount St. Helens National Volcanic Monument, WA – Washington, United States – photo 13

Today we visited Mount St. Helens National Volcanic Monument and enjoyed a few hours at the park. It was a lovely drive, great weather, and I was surprised at how lightly used the park was. We started with a visit to the education center where we watched a 20 minute film about Mt. St. Helens. This is what I learned:

On May 18, 1980, at 8:32 AM, Mount St. Helens experienced the deadliest and most economically destructive volcanic event in U.S. history:

  • The Trigger: A 5.1 magnitude earthquake triggered a massive collapse of the mountain’s north face, causing the largest subaerial debris avalanche recorded in modern human history.

  • The Lateral Blast: Uncapping the pressurized magma chamber unleashed a supersonic lateral blast that leveled roughly 230 square miles of old-growth forest in minutes.

  • The Aftermath: * 57 people lost their lives (including volcanologist David Johnston).

    • The summit elevation dropped by 1,314 feet (from 9,677 ft down to 8,363 ft), leaving behind a massive, 1-mile-wide, horseshoe-shaped crater.

    • An ash column climbed 80,000 feet into the atmosphere, darkening skies across eastern Washington and circling the globe within 15 days.

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