Sunday, May 07, 2006

Mount St. Helens Still Active

We haven't seen this covered much, but think it should be. The U.S. Geological Survey is closely watching a "hulking slab of rock that's rapidly growing" in Mount St. Helens' crater.

More from the Associated Press:

It's jutting up from one of seven lobes of fresh volcanic rock that have been pushing their way through the surface of the crater since October 2004.

The fin-shaped mass is about 300 feet tall and growing 4 feet to 5 feet a day, said Dan Dzurisin, a geologist at the U.S. Geological Survey.

The observatory opened for the summer season on Friday. The day dawned with clear blue skies over the southwest Washington volcano, with snow-covered features within the crater easily visible from a Web camera at Johnston Ridge. The National Weather Service said clouds should move in on Saturday, with rain likely Sunday.

The rock in the crater began growing last November, steadily moving west and pushing rock and other debris out of its way as it goes.

Mount St. Helens, located in the Cascades of Washington, has been quietly erupting since a flurry of tiny earthquakes began in late September 2004.


The volcano has continued pumping out lava ever since. Eventually, scientists expect the volcano will rebuild its conical peak that was obliterated in the May 18, 1980 eruption that left 57 people dead.

The current growth of the new lava dome has been accompanied by low seismicity rates, low emissions of steam and volcanic gases and minor production of ash, the USGS said.

"Given the way things are going now, there's no hint of any sort of catastrophic eruptions," USGS geologist Tom Pierson said. "At any time, however, things can change."

The USGS web site has some nice photos showing the growth of the rock slab. We especially like this one.