Dave visits with legendary United States Geological Survey volcanologist Donald Swanson in this look back at the eruption of Mt. St. Helens on May 18, 1980.
Preceded by weeks of earthquakes and minor eruptions, Mt. St. Helens exploded in violent fury on that fateful spring morning in the Pacific Northwest, taking 57 lives and devastated millions of cubic meters of timber, killed thousands of big game animals, destroyed 250 homes and wiped out hundreds of miles of highway. It was the largest and most destructive eruption in US history, unleashing 1,600 times the energy of the atomic bomb that exploded over Hiroshima.
Don Swanson was a member of the USGS team that was deployed to investigate the volcano prior to, and in the aftermath of the eruption. He tells Dave of his memories of colleague Dave Johnston who was killed by the blast, as well as Harry Truman, the iconic owner of the lodge at Spirit Lake who refused to leave his home and was buried in the cubic mile of material erupted by the mountain on that fateful day.
You'll also hear Don explain how the eruption featured multiple overlapping events: the landslide, violent pyroclastic blasts, towering eruption clouds and debris flows that cost lives and virtually wiped out what was a recreational paradise and area of natural resources such as timber, fisheries and wildlife.
Previously, the largest eruption of an mainland American volcano was Northern California's Lassen Peak in 1915, but that event pales by comparison to the St. Helens blast, which was precipitated by the largest landslide ever recorded -- unleashing a lateral blast that destroyed forests and took dozens of lives.
When Swanson and his colleagues deployed to the Pacific Northwest in March of 1980, the understanding of our Cascade volcanoes was in its infancy. Now virtually the entire chain is both monitored and studied extensively from California to Washington.
Today, Mt. St. Helens is a National Monument and a natural laboratory where geologists from around the world come to visit the mountain, which was last active from 2004-2008. Today, the landscape is a place where people can see how nature recovers from volcanic devastation