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Mount Saint Helens
Mount Saint Helens, active volcano, southwestern Washington, in the Cascade Range. The volcano, which had been dormant since 1857, began to show signs of renewed activity in early 1980 when a column of magma began pushing up inside the mountain, causing the north face of the mountain to bulge out. On May 18, 1980, an earthquake caused a landslide on the mountain's north face, taking off the top of the mountain. The landslide triggered the main eruption by “uncorking” the column of magma that had been building up. The eruption spewed a cloud of ash and gases as high as 19 km (12 mi). The blast killed 57 people and damaged life in an area of some 180 sq km (some 70 sq mi), and a vast area was covered with ash and debris. As a result of the eruption, the mountain's elevation was decreased from 2,950 m (9,677 ft) to 2,550 m (8,365 ft).
Minor eruptions occurred in 1982, 1986, and 2004-2005. Mount Saint Helens is slowly rebuilding itself as magma and ash fill in the crater left behind by the 1980 explosion. Scientists are monitoring the mountain closely, but they are unsure whether to expect a larger eruption during the next few years. The Mount Saint Helens National Volcanic Monument was established around the mountain in 1983.
Eruption of Mount Saint Helens
The volcano known as Mount Saint Helens, in the southwestern portion of Washington state in the United States, began to erupt on March 27, 1980, after a long period of dormancy. It continued to burble until its first large-scale eruption on May 18, 1980. This violent blast sent clouds of ash and other volcanic debris into the atmosphere and killed 57 people. With the eruption, the mountain's elevation dropped from 2950 m (9677 ft) to 2550 m (8365 ft).
Photo Researchers, Inc./Krafft-Explorer/Science Source
