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Mount St. Helens

Mount St. Helens , located in southwestern Washington about 50 miles northeast of Portland, Oregon, is one of several lofty volcanic peaks that dominate the Cascade Range of the Pacific Northwest; the range extends from Mount Garibaldi in British Columbia, Canada, to Lassen Peak in northern California. Geologists call Mount St. Helens a composite volcano (or stratovolcano), a term for steepsided, often symmetrical cones constructed of alternating layers of lava flows, ash, and other volcanic debris. Composite volcanoes tend to erupt explosively and pose considerable  danger to nearby life and property. In contrast, the gently sloping shield volcanoes, such as those in Hawaii, typically  erupt nonexplosively, producing fluid lavas that can flow great distances from the active vents. Although Hawaiian-type  eruptions may destroy property, they rarely cause death or injury. Before 1980, snow-capped, gracefully symmetrical  Mount St. Helens was known as the “Fujiyama of America.” Mount St. Helens, other active Cascade volcanoes, and  those of Alaska form the North American segment of the circum-Pacific “Ring of Fire,” a notorious zone that produces frequent, often destructive, earthquake and volcanic activity.

Some Indians of the Pacific Northwest variously called Mount St. Helens “Louwala-Clough,” or “smoking mountain.” The modern name, Mount St. Helens, was given to the volcanic peak in 1792 by Captain George Vancouver of the British  Royal Navy, a seafarer and explorer. He named it in honor of a fellow countryman, Alleyne Fitzherbert, who held the title Baron St. Helens and who was at the time the British Ambassador to Spain. Vancouver also named three other  volcanoes in the Cascades–Mounts Baker, Hood, and Rainier–for British naval officers.

Mount St. Helens was getting ready to burst for nearly two months before it exploded, not to mention the more than 120 years it lay dormant. While the eruption was anticipated, the manner in which it occurred was completely unprecedented. At 8:32 a.m. on May 18, 1980, a 5.1-magnitude earthquake triggered a sideways blast that swept the mountain’s north face away into a cascading landslide that shot hot ash and stone out some 15 miles at speeds of at least 300 m.p.h. At the same time, a mushroom-shaped plume of ash shot 16 miles into the air, eventually covering three states. Complete darkness blanketed Spokane, Wash., a city about 250 miles northeast of the volcano. When the ash came down it fell in the form of black rain that literally coated the residents of Washington, Idaho and parts of Montana with a fine gray powder. Fifty-seven people and thousands of animals were killed, and some 200 square miles of trees were obliterated. In 1982, Congress and President Ronald Reagan designated the surrounding land as the Mount St. Helens National Volcanic Monument.  (This information was found here )

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This photograph of downed trees was taken on June 8, 1980, a few weeks after the eruption.

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Heavily damaged car embedded in gray soil

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Spirit Lake and Mount St. Helens

Mt. St Helens during 2005 volcanic activity.

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The location of Mt St Helens and key places around it are shown in the satellite image above.

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Mount St. Helens, moments after the landslide that triggered the May 18, 1980 eruption.

A lovely Indian legend about Mt. St. Helens says that before Mt. St. Helens blew its top it was a beautifully symmetric rounded snow-capped mountain that stood between two powerfully jagged peaks, Mt. Hood (which Indians called Wy’east) and Mt. Adams (which Indians called Klickitat).  According to one Indian legend, the mountain was once a beautiful maiden, “Loowit”.   When two sons of the Great  Spirit “Sahale” fell in love with her, she could not choose between them. The two braves, Wyeast and Klickitat fought  over her, burying villages and forests in the process ( hurling rocks as they erupted?). Sahale was furious. He smote the three lovers and erected a mighty mountain peak where each fell. Because Loowit was beautiful, her mountain  (Mount St. Helens) was a beautiful, symmetrical cone of dazzling white. Wyeast (Mount Hood) lifts his head in pride, but Klickitat (Mount Adams) wept to see the beautiful maiden wrapped in snow, so he bends his head as he gazes on St. Helens. 

Mt. Saint Helens National Volcanic Monument

Despite the troubled economy in early 1980s, tens of thousands of visitors flocked to the area surrounding Mount St.
Helens to marvel at the effects of the eruption. On August 27, 1982, President Reagan signed into law a measure
setting aside 110,000 acres around the volcano as the Mount St. Helens National Volcanic Monument, the nation’s first
such monument managed by the USFS. At dedication ceremonies on May 18, 1983, Max Peterson, head of the USFS,
said,”we can take pride in having preserved the unique episode of natural history for future generations.” Since then,
many trails, viewpoints, information stations, campgrounds, and picnic areas have been established to accommodate
the increasing number of visitors each year. Beginning in the summer of 1983, visitors have been able to drive to Windy
Ridge, only 4 miles northeast of the crater. From this spectacular vantage point overlooking Spirit Lake, people see
firsthand not only the awesome evidence of a volcano’s destruction, but also the remarkable, gradual recovery of the
land as re-vegetation proceeds and wildlife returns.

Mountain climbing to the summit of the volcano has been allowed since 1986, and winter exploration of the crater itself is
a difficult but rewarding adventure. A majestic Visitor Center was completed in December 1986 at Silver Lake, about 30
miles west of Mount St. Helens and a few miles east of Interstate Highway 5; by the end of 1989, the Center had hosted
more than 1.5 million visitors. Scheduled for opening in 1992 or 1993 is an interpretation complex in the Coldwater
Lake-Johnston Ridge area, from which visitors will be able to view the inside of the crater and its dome from the site of
David Johnston’s camp on the morning of May 18, 1980.

The National Volcanic Monument preserves some of the best examples and sites affected by volcanic events for
scientific studies, education, and recreation. Intensive monitoring of the volcano is now all the more important to ensure
the safety of the scientists and the monument’s visitors.

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