panorama at the crater rim, october 2010
Prior to May 18, 1980, 9,677 ft. Mount St. Helens was Washington's fifth-highest peak. Towering above Spirit Lake, this beautiful volcanic cone rose over 5,000 feet above its base.
Known to Native Americans as "Louwala-Clough", which means "smoking mountain". St. Helens was also nicknamed "Fuji-san of America" for it's resemblence to Japan's famous Mt. Fuji.
Formed within the last 40,000 years, Mount St. Helens is geologically young compared to the other major volcanoes of the Cascade Range and is considered the most active volcano in the range for the past 10,000 years or so.
Mount St. Helens was quite popular with mountaineers and had many routes on its snowy slopes and glaciers.
On March 20, 1980 a 4.2 earthquake was experienced on the mountain. On March 27, steam began to vent. By the end of April, the north side began to bulge. A second earthquake, of magnitude 5.1, triggered a collapse of the North Face causing the largest known debris avalanch in recorded history.
The magma burst into a large-scale pyroclastic flow, flattening forest and buildings over 230 square miles. More than 1.5 million metric tons of sulpher dioxide was released into the atmosphere. A plume of ash erupted for over nine hours, rising 12-16 miles above sea level and moving eastward at 60 mph, reaching Idaho by noon.
By 5:30 p.m. the ash column declined and less severe outbursts continued over the next several days.
The May 18, 1980 eruption released 24 megatons of thermal energy, and ejected over 0.67 cubic miles of material. The mountain was reduced in heigth by approx. 1,300 feet, leaving a one to two mile wide crater, 0.5 miles deep with it's north side open. 57 people died, nearly 7,000 big game animals and an estimated 12 million fish, from a hatchery also died in the eruption. 200 homes were destroyed or severly damaged. 185 miles of highway and 15 miles of roadways were also destroyed.
In progress, more to come.
The easiest way to reach Mt. St. Helens is from I-5. From exit 49 take 504 to the mountain.
Weather station 4.9 miles from here
2 Total Routes
['4 Stars',0],['3 Stars',0],['2 Stars',2],['1 Star',0],['Bomb',0]
Browse More Classics in Mount St. Helens
Mountain Project's determination of some of the classic, most popular, highest rated routes for Mount St. Helens:
Featured Route For Mount St. Helens
Easy Snow PG13 WA
: Southwest Cascades
: Mount St. Helens
This is the most popular and crowded route to the summit in the summer. The first 2.1 miles of the trail are a hike through forests. When you cross Loowit Trail there is a toilet on the right. After this the trail follows the rocky ridge and is marked by large wooden posts almost to the summit. You'll pass a couple tripod monitors on the ridge that give it its name. After the last post, just follow the ridge to the summit. In the summer, it's a dusty crowded hike. In the winter, you'll want cram...[more] Browse More Classics in WA
Latest Regional Forum Messages
07-22-1980 eruption. Wikipedia photo.
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April 10, 1980 eruption. Wikipedia photo.
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May 19, 1980 eruption of Mount St. Helens. Wikipe...
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