Brain Bubbles

Expressions of a caffiene regulated brain.


Friday, October 01, 2004

Mt St Helens

I hope that everyone in that area is aware of this situation and ready to evacuate if neccessary - don't forget your pets folks! This was emailed to me as a google alert for something totally unrelated but it is nevertheless v v V important! Mount St. Helens Eruption Imminent, Experts Say Stefan Lovgren for National Geographic News September 30, 2004 Washington State's Mount St. Helens volcano is primed to erupt any day now, according to scientists. They predict the blast will be far less powerful than the May 18, 1980, explosion that killed 57 people. "There's been so much activity [that] we're definitely expecting something to happen," said Tom Pierson, a research scientist with the U.S. Geological Survey at the Cascade Volcano Observatory in Vancouver, Washington. "But," he added, "it's nowhere near what we saw in 1980." When Mount St. Helens began stirring last week, scientists first assumed the tiny earthquakes underneath the volcano were being caused by steam from water seeping into the mountain. This usually happens in the fall. As rainwater encounters hot rock that has had the summer to dry out, the resulting steam pressures the system underneath the volcano and causes the rock to fracture. Only, this time, the earthquakes grew stronger and became increasingly frequent. That led scientists to believe that something else was moving and pushing up from below: magma. Magma, or molten rock, is formed when a part of the Earth's lower crust or upper mantle melts. The movement of magma causes volcanic activity. As rock inside the Earth melts, it can rise toward the surface and may erupt in a volcano. On May 18, 1980, that's what happened at Mount St. Helens, which is located 100 miles (160 kilometers) south of Seattle. The blast blew off the top of the mountain, killing 57 people and showering towns as far as 250 miles (400 kilometers) away with volcanic ash. Earlier today the flurry of earthquakes had intensified, striking four times per minute, prompting scientists to warn that a small or moderate blast is imminent. Steam explosions would probably precede a small blast, throwing rock around inside the crater and maybe as far as three miles (five kilometers) from the volcano. An eruption could create an ash cloud that could rise to 2,000 feet (600 meters), but the cloud wouldn't be very big.  Posted by Hello