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Redoubt eruption sequence is Earth Science Picture of the Day 13 February 2010

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The Universities Space Research Association Earth Science Picture of the Day for 13 February 2010 is a sequence taken by the USGS’s Bill Burton showing the first known ash emission of the March 2009 eruption of Redoubt Volcano. The activity shown in the sequence took place on 15 March 2009, and the full-scale eruption began one week later. There is a helpful and informative caption with the images, but it’s very sad to see a reputable academic site linking not once but twice to articles at a popular and laughable user-edited internet encyclopedia rather than taking the trouble to find and refer to proper sources. This kind of thing should not be encouraged: the internet is dumb enough already.

[H/T: Callan Bentley, NOVA Geoblog.]

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Redoubt quiet, back to Normal/Advisory 12 January 2010

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A bit late catching up with this, but the Alaska Volcano Observatory returned Redoubt to Normal/Advisory status on 5 January 2010: ‘The swarm of small, shallow earthquakes that began Sunday, December 27 has ceased and the degree of seismic activity beneath the volcano has returned to background levels. Aerial observations of the new lava dome on December 31 indicated no obvious changes at the surface and no sign of instability’.

News
AVO lowers Redoubt alert level to green – KTUU.com, 5 January 2010
Alaska volcano back at ‘normal’ statusSeattle Times, 5 January 2010
Mount Redoubt is back to code green – Radio Kenai, 6 January 2010

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog

Redoubt rumbles reducing 2 January 2010

Posted by admin in activity reports, Alaska, Redoubt, United States.
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Alaska’s Redoubt volcano seems to be calming down after its recent burst of seismic activity, which led to an increase in the alert level to Yellow/Advisory on 28 December 2009. The weekly bulletin issued on 1 January 2010 by the Alaska Volcano Observatory reports that the ‘swarm of shallow, small earthquakes that began last Sunday, December 27 at Redoubt Volcano has greatly diminished or ceased’, and that an aerial inspection on 31 December showed no changes in the appearance of the volcano and no sign of instability at the lava dome. Surface temperatures at the dome remain high, in line with expectations, while magmatic gas output from the dome area ‘is somewhat elevated compared to the last measurement in early November’.

The scientists at the Alaska Volcano Observatory are continuing to examine what might have caused the recent activity: one possible cause is ‘input of new magma or remobilization of existing magma within volcano’s shallow plumbing system’. AVO notes that the process ‘appears to have ceased or paused’, but may reappear and possibly lead to additional eruptive activity, although the ‘sharp increase in seismicity and other marked changes prior to such activity’ would provide some warning of what was going on. For the moment AVO is keeping a close watch on things, and Redoubt remains at Yellow/Advisory.

News
Redoubt rumblings continue to ease, scientists say – KTUU.com, 1 January 2010
Flyover shows Redoubt appears unchangedAnchorage Daily News, 1 January 2010

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog

Catching up: Mayon, Redoubt, Poás, Saudi Arabia… 31 December 2009

Posted by admin in activity reports, Alaska, Costa Rica, Mayon, Philippines, Poás, Redoubt.
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The Volcanism Blog Christmas Break lasted a little longer than intended, as round here the internet celebrated the holiday season by breaking down and we’ve only just got it back. Here’s a summary of what’s been going on in the meantime.

Mayon has so far stopped short of the big explosive eruption that everyone has been expecting (although the full moon might do it). Some 50,000 people have spent Christmas as evacuees in temporary shelters, and it does not look as if they will be returning to their homes any time soon. Meanwhile the authorities are losing patience with people who refuse to quit the danger zone: power and water supplies to evacuated areas are to be cut off, and the Philippine Commission on Human Rights has okayed ‘forcible evacuation’ measures. The latest Phivolcs bulletin (no. 18, 31 December 2009) reports continuing ‘extrusion of lava and rolling down of incandescent lava fragments’. Poor visibility has hampered observations of the volcano, but no ash explosions have been observed during clear periods. The last significant explosion (to 9,000 feet/2,740 metres) was reported by Tokyo VAAC at 00:17 UTC on 30 December. The alert status for Mayon remains at the second-highest level of 4; the level of activity has declined somewhat over the last few days, but Phivolcs warns that the threat remains.

In Alaska, Redoubt stirred for the first time in five months or so, altering its usual seismic behaviour to produce a series of small repetitive earthquakes near its summit. The Alaska Volcano Observatory raised the alert level for Redoubt to Yellow/Advisory on 28 December 2009. The latest AVO bulletin (30 December 2009, 21:46 UTC) reports that the earthquake activity has declined markedly.

Poás in Costa Rica revealed itself to have a great sense of occasion, putting on a fine display of phreatic activity on Christmas morning. A mixture of sediments and water from the crater lake and volcanic blocks was ejected to a height of more than 500 metres at 09:50 on Christmas Day, startling visiting parties of festive tourists.

Remember the earthquakes in the Al-Ais region of Saudi Arabia earlier this year? The last tremors were reported in June. It seems that there were some more earthquakes on 18 December, causing alarm among local residents who have only recently returned to their homes after being evacuated in May and June. The Saudi Geological Service has said that the tremors are normal for this volcanic region of the country, no eruption is imminent, and that there is no need for new evacuations.

The Global Volcanism Program has published two weekly volcanic activity reports over the holiday period, one covering 16-22 December 2009 and one for 23-29 December 2009. Full posts for both of these will be published here next week.

Happy New Year!

The Volcanism Blog

Contrasting views on the Drift River Oil Terminal 2 October 2009

Posted by admin in Alaska, eruptions, natural hazards, Redoubt.
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Lahars near Drift River Oil Terminal, 4 April 2009 (NASA EO-1 image).

Two contrasting views of the Drift River Oil Terminal saga have been published in the Homer Tribune. Michael Munger of the Cook Inlet Regional Citizens Advisory Council presents a positive view: ‘In the recent situation with Mount Redoubt and the Drift River Oil Terminal, the unified command worked exactly the way it was intended, resulting in a successful response to the volcanic mudflow threatening the facility. As a result, no people were injured and no oil was spilled’. In the other corner, Bob Shavelson of environmental organization Cook Inletkeeper: ‘The fact remains that the Drift River Oil Terminal incident stands out as the most significant breakdown in spill prevention and response in Alaska since the Exxon Valdez Oil Spill. That breakdown put our fishermen, workers and countless families and businesses around Cook Inlet at extreme risk’.

The central point is that the Drift River Oil Terminal should not be where it is. If it was not in a dangerous location in the first place none of the impressive hazard management Michael Munger talks about would be necessary.

[Image of the Drift River Oil Terminal and lahars from Mount Redoubt: NASA Earth Observatory, 9 April 2009, originally posted here; see also Drift River Oil Terminal vs. the volcano.]

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Redoubt back to Green/Normal 30 September 2009

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The Alaska Volcano Observatory lowered Redoubt’s status to Aviation Colour Code Green and Volcano Alert Code Normal at 18:44 GMT (10:44 AKDT) yesterday, 29 September 2009. According to the Volcanic Activity Notice issued by the AVO …

Over the past several months, seismic activity, volcanic gas output, ground deformation, lava dome temperatures, and outward signs of lava dome instability at Redoubt Volcano have been declining. The volcano appears to have returned to its normal background condition and for now poses no immediate threat of eruptive activity. Accordingly, AVO is lowering the Aviation Color Code to GREEN and the Volcano Alert Code to NORMAL.

The AVO notes that the Redoubt lava dome has reached a volume of approximately 70 million cubic metres, and that lava domes on steep slopes are ‘typically unstable’. However, given that 60 days have passed since the dome ceased to grow, ‘AVO believes the possibility for dome collapse is small and declining toward a background level of danger typical of many active stratovolcanoes with steep unstable rock slopes’. Local hazards remain, associated with the hot lava dome: gas emission, abundant steaming, rockfalls, but these do not pose a significant hazard beyond the summit area of the volcano.

With Redoubt now at Green/Normal, only Shishaldin among the AVO’s charges remains at Yellow/Advisory, because of its sustained but low-level seismic rumblings.

For all our Redoubt coverage: Redoubt « The Volcanism Blog.

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog

Snowy Redoubt steams, but activity remains low 21 September 2009

Posted by admin in activity reports, Alaska, Redoubt, United States.
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Redoubt, 18 September 2009 (image courtesy of Dennis Anderson, Night Trax Photography)

The weather around Redoubt volcano in Alaska cleared over the last few days to reveal a prominent steam plume, but this does not indicate a renewal of activity. The Alaska Volcano Observatory has confirmed that the heating of fresh snowfall on the summit is the source of the plume, and that seismic activity at the volcano continues to decline. The most recent AVO status reports say that the lava dome is cooling, and that, while the threat of a collapse remains, that threat is declining over time.

Redoubt is at alert level Yellow/Advisory, but Chris Waythomas of the AVO is quoted by the Peninsula Clarion as saying ‘It’s headed toward background activity, though. I wouldn’t be surprised if it was downgraded to green next month’.

[Image of Redoubt taken 18 September 2009, courtesy Dennis Anderson, Night Trax Photography.]

For all our Redoubt coverage: Redoubt « The Volcanism Blog.

News
Redoubt steams, but seismic activity declines – KTUU.com, 20 September 2009
Still steaming: Redoubt’s seismic activity decliningPeninsula Clarion, 20 September 2009

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog

Drift River Oil Terminal: what next? 28 August 2009

Posted by admin in Alaska, natural hazards, Redoubt, United States.
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The future of the Drift River Oil Terminal remains unclear, after a public meeting on Monday night that brought together the agencies responsible for the terminal and members of local communities revealed that no-one, including the people running the place, knows quite what happens next.

The oil terminal, which stands at the mouth of the Drift River in the path of lahars from Redoubt volcano (which continues to exhibit ‘significant activity’), was shut down after Redoubt erupted in March, and was finally drained of most of the stored oil that remained on-site at the end of April and beginning of May. There was talk in mid-July of the terminal coming back on line this month, but that seems to have been quietly forgotten. The word that came from the Cook Inlet Pipeline Company (CIPL) at the meeting, reports the Peninsula Clarion, is that the terminal ‘won’t be used to store more oil anytime in the near future’, but beyond that things are very vague. ‘We will work on long term plans’, says CIPL’s Rod Ficken, ‘there are a lot of different scenarios on the table’. In the immediate future a ‘tightline’ system will be used with oil stored in company tanks and piped direct to tankers without being stored at Drift River; longer term, tankage may be expanded at other regional facilities.

Meanwhile the ‘Unified Command’ established in March to oversee the terminal during the eruption is to disband and the facility is to be run and regulated as normal, a process which will involve using ‘transition’ as a verb:

Gary Folley, the state on-scene coordinator for DEC [Alaska Department of Environmental Conservation], complimented the UC [Unified Command] Monday night, on the responses and actions taken though the situation.

‘The formation of Unified Command was a big improvement from the response organization in 1989 and ’90. The main thing is that all the key decision makers were in one place and this allowed for quick decisions … It is now time for Unified Command to stand down. Regulatory oversight of the terminal will transition back to normal agency functions’, he said.

Environmental pressure group Cook Inletkeeper have long been worried about oil being stored at the Drift River terminal. Now that it seems oil will not be stored there but piped direct to tankers they are worried about that instead: ‘now, with the implementation of tightline operations, tanker traffic in the inlet will increase, posing the potential for new and increased risks’.

News
Public to hear plans for Drift River terminalAnchorage Daily News, 14 August 2009
Kenai town hall discusses crude oil stored near Mount Redoubt – KTUU.com, 24 August 2009
No new oil to be stored near Mount Redoubt – KTUU.com, 25 August 2009
Sleepy but not gone to bed: Mount Redoubt continues to exhibit ‘significant activity’Peninsula Clarion, 26 August 2009
Oil terminal to stay unused: Cook Inlet production not anticipated to fully recoverPeninsula Clarion, 26 August 2009

The Volcanism Blog

Drift River Oil Terminal back on line next month 14 July 2009

Posted by admin in activity reports, Alaska, eruptions, natural hazards, Redoubt, United States.
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In response to ‘a significant decrease in the rate of lava extrusion’ and indications that the growth of the lava dome had ‘significantly slowed, if not stopped’, the Alaska Volcano Observatory lowered the alert level at Redoubt volcano to aviation colour code Yellow and volcano alert level Advisory at the end of last month (AVO advisory 30 June 2009). The eruption may be coming to an end … or it may very well not. In an extended information statement, the AVO warns:

Despite evidence for the significant slowing, and possible cessation of its growth rate, the lava dome is potentially unstable and the possibility of a full or partial collapse remains high at present. Such a collapse would likely be accompanied by the production of a large ash plume and lahars in the Drift River valley. This event could occur with little or no advance warning.

Against this background comes the news that the Cook Inlet Pipe Line Company is planning to have the Drift River Oil Terminal back on line by the middle of next month. The terminal is 40 km from Redoubt’s main vent, at the mouth of the Drift River Valley, which forms a channel for the volcano’s lahars. Plans are apparently in hand to modify the facility so that oil will be shipped directly from the pipeline into tankers, by-passing the vulnerable storage tanks that have been the focus for much concern.

This will get the oil flowing and the people working again (dome collapses and lahars allowing) but the long-term future of the terminal is unclear: ‘The facility remains in pretty good shape’, says CIPL spokesman Casey Sullivan, ‘the concern is the location.’ No kidding.

For all our Redoubt coverage: Redoubt « The Volcanism Blog.

News
Volcano-halted Alaska oil production to resume – Reuters, 13 July 2009
Cook Inlet pipeline operations expected to resume in August – Radio Kenai, 13 July 2009

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog

Redoubt calms down a little bit 8 May 2009

Posted by admin in activity reports, Alaska, Redoubt, United States.
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Seismicity at Redoubt has dropped over the last 36 hours, reports the Alaska Volcano Observatory, although it remains at an elevated level. ‘This change does not’, warns the AVO, ‘negate the possibility of an explosive eruption over the coming days’.

Webcam views show Redoubt producing a low but vigorous steam plume. No ash emissions have been detected.

For all our Redoubt coverage: Redoubt « The Volcanism Blog.

Information
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO

The Volcanism Blog