January 26, 2005

Dome Building Slows at Mount St. Helens

SEATTLE (AP) -- Growth of the new lava dome inside the crater of Mount St. Helens has gradually slowed since the mountain reawakened in October, scientists said Tuesday.

Molten rock has been oozing out from the surface of the volcano's crater since the fall, building a new lava dome that now has a total volume of 44 million cubic yards. That is big enough to contain 134 buildings the size of the basketball arena where the Portland Trailblazers play.

Scientists provided an update on Mount St. Helens from the Cascade Volcano Observatory in Vancouver, about 50 miles south of the peak, nine days after a small explosion at the north end of the new dome sent ash nearly 2 miles from the crater.

The explosion Jan. 16 destroyed a camera and some measuring equipment that had been placed in the crater. The blast was on a similar scale to explosive events in October, U.S. Geological Survey research hydrologist Jon Major said.

The 1980 eruption of the volcano 100 miles south of Seattle blew the top off the 9,677-foot peak, killed 57 people and covered the region with gritty ash.


U.S. Geological Survey: http://www.usgs.gov