No Doubt about Redoubt Volcano!
Posted by feww on February 4, 2009
Latest photo of Alaska’s Redoubt Volcano
Hot smoke and gas were ejected from two new fumaroles that appeared in the snow and ice layer on Alaska’s Redoubt Volcano.
Photo by Chris Waythomas, Alaska Volcano Observatory /U.S. Geological Survey (USGS)
The AVO researchers reported that the ice layer surrounding the volcano is melting rapidly because of the hot gasses that are spewing out of the fumaroles. The gases reportedly include carbon dioxide, hydrogen sulfide, and sulfur dioxide, which means magma is edging upward. AVO scientists also believe new magma has entered Redoubt, which means that there is strong possibility the volcano will explode in the near future.
The 3,108-meter volcano, considered the 9th most active in the U.S., is about 170 kilometers from Anchorage, Alaska.
AVO report dated 2009-02-03 15:02:56
“Unrest at Redoubt Volcano continues. Seismic activity remains elevated above background. Clear web camera images show no activity at the volcano. An AVO crew is working near the volcano today. They have installed one new seismic station and are presently working on a second installation. AVO is monitoring the volcano 24 hours a day.”
AVO Redoubt Scenarios
Based on their knowledge of Redoubt’s past activities, both historical and from the geologic record, and their analysis of the current episode of unrest, AVO suggests four possible scenarios:
- Failed Eruption
- ERUPTION SIMILAR TO OR SMALLER THAN 1989-90
Unrest continues to escalate culminating in an eruption that is similar to or smaller than the one that occurred in 1989-90. - Larger [than 1989-90] Explosive Eruption
- Flank Collapse
Based on all available monitoring data and AVOs knowledge of the volcano, scenario number two, an eruption similar to or smaller than that of 1989-90, appears to be the most probable outcome at this time. We consider one and three to be somewhat less likely, and scenario four to be much less likely. —AVO
For more information see Redoubt Interpretation and Hazards.
Geologic Summary: Redoubt is a 3108-m-high glacier-covered stratovolcano with a breached summit crater in Lake Clark National Park about 170 km SW of Anchorage. Next to Mount Spurr, Redoubt has been the most active Holocene volcano in the upper Cook Inlet. Collapse of the summit of Redoubt 10,500-13,000 years ago produced a major debris avalanche that reached Cook Inlet. Holocene activity has included the emplacement of a large debris avalanche and clay-rich lahars that dammed Lake Crescent on the south side and reached Cook Inlet about 3500 years ago. Eruptions during the past few centuries have affected only the Drift River drainage on the north. Historical eruptions have originated from a vent at the north end of the 1.8-km-wide breached summit crater. The 1989-90 eruption of Redoubt had severe economic impact on the Cook Inlet region and affected air traffic far beyond the volcano. [Source: GVP]
Related Links:
- Earthquake Forecast 2009 : Japan
- A New Era of Intense Volcanic Unrest May Have Begun
- Earthquakes [Links page]
Content: 500 words, 1 image, 8 links
Fire Earth 
feww said
UPDATE:
Redoubt still restless, but no eruption
Associated Press – February 20, 2009 5:44 PM ET
ANCHORAGE, Alaska (AP) – Scientists say unrest continues at Mount Redoubt, but there’s still been no eruption at the volcano a hundred miles southwest of Anchorage.
The Alaska Volcano Observatory says there’s been intermittent earthquakes throughout the week.
Scientists didn’t perform any field work at Redoubt this week, but say a gas-measurement flight is scheduled for Saturday, weather permitting.
In late January, the observatory began detecting a sharp increase in earthquakes beneath Mount Redoubt. Geologists have since warned that an eruption could occur at any time. However, they say it also is entirely possible the volcano won’t erupt.
Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
http://www.ktuu.com/Global/story.asp?S=9880780