Mount St. Helens' dome in crater continues to grow

By Seattle Times staff

E-mail this article Print this article Search archive Most read articles Most e-mailed articles

Related stories Taming the Toutle River Other links Mount St. Helens VolcanoCam Mount St. Helens Seismicity Information Mount St. Helens National Volcanic Monument Mount St. Helens remembered Photo gallery: Mount St. Helens, then and now

Field crews at Mount St. Helens were attempting yesterday to take aerial photos and thermal images of the swelling lava dome inside the volcano's crater.

Attempts to make such observations Saturday were foiled by inclement weather.

Officials at a volcano headquarters in Vancouver, Wash., did not report yesterday whether the latest flight attempts were successful.

Scientists say the lava dome continues to grow and has surpassed 900 feet in length, 250 feet in width and 230 feet in height, a structure they compare to the size of an aircraft carrier.

But the volcano has quieted since the flurry of earthquake activity and plumes of ash it spit out as it reawakened a month ago.

Seismic activity remained low yesterday, with slight rumbles consistent with a slow, continuous rise of magma to add to the lava dome. The low quake rate probably means the magma doesn't have much gas in it, scientists say. And that means a low risk of an explosive eruption in the near future, they said.

But they aren't ruling out the possibility of small lahars, or mudflows, if heavy rains come or hot magma continues to melt glacial ice.

However, they said any mudflows would not reach inhabited areas around the Toutle River below the mountain.

Though a large eruption is deemed unlikely, it remains possible, so a five-mile radius around the volcano remains closed, including the Johnston Ridge Observatory.

Scientists have consistently said this latest activity will not result in a catastrophic eruption like the one May 18, 1980, that killed 57 people.

Copyright © 2004 The Seattle Times Company

E-mail this article

Print this article

Search archive

More local news headlines...