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Volcano Web /

Volcanic Places in the USA

 Listed below are two places in the United States that are considered "active" volcanic areas.

Mount St Helens Long Valley
On May 18, 1980, after a long period of rest, this quiet mountain in Washington provided detailed observations on the mechanics of highly explosive eruptions. The towering pine trees of this once-quiet mountain were toppled over like toys. This field seismometer measures earthquakes associated with subsurface volcanic forces and may help to predict future events. It sits on a plateau known as the "Volcanic Tableland" formed by a major eruption 600,000 years ago. link to large image
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San Francisco Peaks MacDougal Crater
Scientists believe that the volcanic eruptions several million years ago that shaped this mountain in northern Arizona were very similar to the ones onserved at Mount St. Helens. When hot volcanic magma encounters ground water, these explosive eruptions can form deep craters seen just south of Arizona in the Pincate Volcanic region of Mexico.