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Mount St. Helens Facts

Mount St. Helens Facts
Mount St. Helens is a volcano located in Skamania County, Washington, most famous for its eruption in 1980 that was the most deadly and expensive eruption in the history of the United States. It is also known as 'Louwala-Clough' or 'Smoking Mountain' by Native Americans. The name Mount St. Helen's came to be when a British Royal Navy Captain named the volcano after Baron St. Helens, a British Ambassador to Spain. It is believed that Mount St. Helens erupted in 1800, and then again in 1898, 1903, and 1932. Until 1980 Mount St. Helens was a recreational area coveted for its beauty. When it erupted on May 18th, 1980, it was changed forever, as its beautiful cone was destroyed and a horseshoe-shaped crater was left in its place.
Interesting Mount St. Helens Facts:
Mount St. Helen's is considered to be the most active volcano in the Cascades for the past 4000 years.
In March of 1980 researchers at the University of Washington began to get readings on their seismographs hinting of earthquake activity.
A 4.2 magnitude earthquake was recorded on March 20th, beginning a watch for further activity 24 hours a day.
On March 27th, 1980 a Hazard Watch was issued by the U.S Geological Survey at 8am. By noon ash and steam were shooting into the air reaching as high as 6000 feet.
On May 18th, 1980 at 8:32 a.m. Mount St. Helens erupted. The eruption followed a 5.1 magnitude earthquake.
The volcanologist responsible for reporting on activity of Mount St. Helens, who was camped on top of a ridge in the blast zone at the time of the eruption was David A. Johnston. His last transmission before the blast was "This is it!" He died moments later.
The eruption began as a landslide. The summit of Mount St. Helens was reduced by 1300 feet.
The lateral blast that followed the landslide scorched 230 square miles of forest as it blasted at a speed of more than 300 miles per hour down the mountain.
Volcanic ash rose to more than 80,000 feet into the air within 15 minutes of the landslide.
The darkness created by the dense cloud of ash turned eastern Washington into night. It became so dark that the streetlights came on automatically.
The ash cloud from the eruption took only 3 days to cross to the United States' east coast. It took 15 days from the eruption for the ash cloud to encircle the earth.
The May 18th, 1980 eruption killed 57 people. It destroyed 250 homes, 185 miles of highway, 15 miles of railway, and 47 bridges.
Mount St. Helens continued to erupt several times in 1980, and although not as explosive as the first, these eruptions sent ash flying to communities in the region.
Between 1980 and 1986 lava eruptions filled the crater.
A glacier formed in the crater named Crater Glacier.
From 2004 until 2008 Mount St. Helens erupted continuously.
Although the beautiful landscape was destroyed, the lava has left behind a rich and diverse landscape where plants and animals are thriving.


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