Mount St. Helens

On 18th May 1980, Mt. St. Helens erupted after an earthquake measuring 5.0 on the Richter scale. The composite volcano is situated in the Cascade Range of the Rocky Mountains on the east coast of America. The eruption killed 64 people, and had a lateral blast range of around 500 km. 24sqkm of forest was flattened, ruining ecosystems and causing timber supplies for the area to dwindle. The blast caused the release of toxic pyroclasts, which were a threatening danger, which luckily didn't cause many deaths. The north face was blown off due to the build-up of pressure caused by magma flow in the volcano. Much of the Mount St. Helens National Park was closed for some ...

Mt. St. Helens erruption information (1980) - had been growing in size since 37,500 years ago 08:32 18th May 1980 - Mt. St. Helens erupted a mile beneath the surface of the volcano. This caused a huge landslide of about 23 square miles Travelled at about 70-150 mph and buried North Folk Toutle River with 600 foot of debris The blast deposit covered 230 square miles around the volcano Results of the blast: enough wood to build 300,000 two bed roomed houses was felled by the blast's debris 57 deaths Debris was about 350 degrees which caused deaths The lahar (mud flow) travelled at 10-25mph ...