Mt. Redoubt Is Stirring

After turning away from matters seismological* after the Yellowstone Lake earthquake swarm, the Ring of Fire has decided to put on a show of its own.

Mount Redoubt, about 100 miles southwest of Anchorage, is preparing to erupt. Starting the weekend of January 24th-25th, 2009, seismic activity suddenly increased, activity that suggested magma was on the move inside the mountain.

Redoubt is known as an active volcano, most recently erupting in 1989-90. Generally, such eruptions are only really hazardous if you are on the mountain, downstream from the mountain on a river or stream fed by flows from the mountain, or downwind from the volcano. Resoubt is relatively remote in that there are no settlements on it; however there are some oil facilities and camps on the Drift River which could be affected by an eruption-generated mudflow. (These mudflows are called lahars, and result from snow and glaciers rapidly melting due to hot ash and pyroclastic flows. This sudden release of water scours the mountainside and collects soil in ash into a thick muddy mass that moves down a river, wreaking havoc. The mudflows on the Toutle River after the Mt. St. Helens eruption in 1980 are a textbook example of the hazard a lahar can pose.)

The real concern is volcanic ash. Volcanic ash in essentially pulverized rock, which means it is abrasive and can be heavy when it is allowed to collect. So, in a state that receives 70% of its supplies through the Anchorage airport will be watching very closely to see which way the wind blows when Redoubt erupts.

More information:
Alaska Volcano Observatory - Mt. Redoubt
Anchorage Daily News



*Sorry about the arch prose. I watched a Sherlock Holmes MYSTERY! last night ("The Second Stain"), and the show had its usual effect. For a period of at least 24 hours after watching, I have to repress urges to walk with a proper cane, smoke a pipe, and talk with a proper English accent. I blame you, Jeremy Brett.