Mount St. Helens lava formation grows
10:33 AM PST on Saturday, November 6, 2004
Associated Press
SEATTLE — A lava formation inside Mount St. Helens' crater has a new, glowing protrusion the size of a 30-story building. The protrusion, which glows red at night, has risen by 330 feet in the past nine days, pushed up by magma, or molten rock, within the volcano, scientists said Friday.

AP/COURTESY USGS
Magma in the crater of Mount St. Helens glows at twilight Thursday from the Johnston Ridge Observatory.
"It seems like every time you think you know what's going on, (the volcano) twists and does something different," said Jeff Wynn, chief scientist for volcano hazards at the Cascades Volcano Observatory in Vancouver.
The overall lava formation began building last month and has grown to roughly the size of an aircraft carrier, 900 feet long and 250 feet wide. Magma is reaching at the surface at the rate of 7 to 8 cubic meters - about one large dump truck load - every second, Wynn said.
"What we have been noticing with this monster is that it was growing at an unusually high rate and it was spreading out horizontally like a big pancake," Wynn said. "And now all of a sudden it's like a huge piston has been thrust up."
Like the old lava dome, formed in the six years after St. Helens' devastating May 18, 1980, eruption, the new formation is made of a type of volcanic rock called dacite, Wynn said. More than 63 percent silica, it tends to be sticky and viscous, unlike the free-flowing lava of Hawaii.