Mount St. Helens

Mount St. Helens is an active volcano in southwestern Washington state. On May 18, 1980, the volcano had a massive eruption. Jim Quiring summarizes this event in the book Mount St. Helens - The Continuing Story:

> In the spring of 1980, Mount St. Helens awakened from a 123 year dormancy. Beginning in late March, and continuing into mid-May, earthquakes and small eruptions shook the mountain. It became fractured, gray with ash, and reshaped with a giant bulge pushing outward on its north face. Then, on the morning of May 18, an earthquake measuring 5.1 on the Richter scale, and a massive rock avalanche from its north flank triggered a powerful lateral eruption. Within minutes, the rock avalanche removed the top 1,300 feet of the mountain; the lateral explosion toppled trees with a searing, stone-filled wind over an area covering more than 150 square miles, now called the "blast zone."

> Clouds of volcanic ash formed a vertical eruption column that rose to over 60,000 feet and then drifted eastward, circling the earth in 15 days. Mudflows poured from the flanks of the volcano into the forested valleys below. Pyroclastic flows, mixtures of superheated gases, broken rock, and ash scoured the sides of the volcano, especially below the new crater. After 9 hours of continuous eruption, the volcano generated smaller ash clouds throughout the evening as the eruption finally ended.

> The eruption claimed the lives of 57 people and changed the lives of thousands of others. People were left with a mixture of feelings including those of personal tragedy and loss, as well as humbleness and awe at the power displayed by the volcano.[1]

# References[edit]

1. ↑ Quiring, James P. Mount St. Helens - The Continuing Story. KC Publications, Inc., Fifth Printing, 2005.

# External Links[edit]

* Mount St. Helens VolcanoCam
* Mount St. Helens Institute
* Cascade Range Volcanoes and Volcanics - Current Update
* Recent Earthquakes in the Pacific Northwest