Friday, May 19, 2006

Mt St Helens May 18, 1980

One day late unfortunately. I totally overlooked the 26th anniversary of the Mount St Helens volcanic eruption.

May 18, 1980 started out as a picture perfect day for the Pacific Northwest. Since it was Sunday, few people (some loggers and scientists, plus a few reporters and the curious) were in the vicinity of Mount St Helens. Since the mountain had been relatively quiet for the past few weeks, these few souls thought they had little to fear.

U.S. Geological Survey vulcanologist David Johnston was taking measurements of the mountain on a ridge a few miles away. At 8:32AM Pacific Time Johnston radioed "Vancouver! Vancouver! This is it!". They were his last words before he was struck by an advancing wall of rock and debris that roared down the mountain at more than 500 miles per hour. His body was never found.

This violent eruption triggered the largest landslide ever recorded. It swept down the mountain at speeds of 70 to 150 miles per hour and buried the Toutle River under an average of 150 feet of debris. Some areas were covered by as much as 600 feet of ash and mud. Approximately 23 square miles of rock and other material was ejected from the mountain.

I knew one person who lived near the eruption in Yakima, Washington. They were in church that AM and heard a faint rumble. Most thought it was a large truck or train, or a distant storm, and thought little of it. A few minutes later a man burst into the church and stood dazed. As the services ground to an awkward stop, the man shouted "don't you see what is going on outside?" They realized the sun was gone and stepped out into a blizzard of ash. I forget these folks name, I went to church with them in Springfield IL. They gave me a lasting gift of some honest to goodness Mt St Helens Ash.

The massive ash cloud reached 80,000 feet in 15 minutes and made it to the east coast in 3 days. Although most of the ash fell within 300 miles of the mountain, finer ash circled the earth and remained in the atmosphere for many years afterwards.

The old girl is rebuilding now. A centuries long cycle of eruptions and quiet periods will rebuild the lava dome and change the look of the mountain again. Once known as the Mt Fuji of America for its resemblance to the perfectly cone-shaped volcano in Japan, St Helens is sleeping now. But it is a restless sleep and future generations may see her fury again.

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