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A short holiday… 27 June 2011

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The Volcanism Blog is taking a short summer break this week and will be back on Monday 4 July. Until then, for all things volcanic Eruptions is your place, as ever.

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The Daily Volcano Quote: volcanoes the safety valves of the globe 24 June 2011

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We regard the existence of volcanoes as evidential of divine benevolence … we refer now to active and not extinct volcanoes. And these, we are aware, are almost universally regarded as exhibitions of the displeasure of God, rather than of his benevolence. It is indeed true, that they are often terrific exhibitions of his power; and when he employs them as penal inflictions, they signally manifest the sterner features of the divine character. Yet we maintain that the design of volcanoes is to preserve and not to destroy. They have been denominated ‘the safety valves of our globe;’ and this quaint expression conveys a forcible idea of what we mean by the benevolent design of this mighty agency. If it be indeed true, as most geologists now admit, that even at this day the earth contains extensive accumulations of intensely heated matter, embracing perhaps all its central parts, then may it be literally true that volcanoes are the safety valves of the globe. For if such molten reservoirs do not occasionally have vent, the vapour and gases generated within them, would burst the globe asunder. The phenomena of earthquakes admonish us of the consequences of closing these valves; for they are produced by the struggles of these vapours and gases to escape; and until they do escape through volcanic vents, they heave and fissure the solid strata over whole continents; and in past days they have been far more destructive to property and life than volcanoes. But so soon as the force is sufficient to lift the safety valve, that is, to uncap the volcano, the earthquake ceases. Let the valve be heavy enough, and the earth would ere long be blown to atoms. To prevent such a catastrophe, God has scattered more than two hundred of these safety valves over its surface.

‘The divine benevolence: illustrated by facts drawn from geology’, The Scottish Christian Herald, vol. 1, no. 23 (6 August 1836), p. 358.

The Daily Volcano Quote: from Monday to Friday, a new eruption of volcanic verbiage each day.

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Puyehue-Cordón Caulle corked: a small-scale case-study of media sensationalism 24 June 2011

Posted by admin in Chile, eruptions, Puyehue.
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Even by the standards of sensationalized volcano stories in the mainstream media the headline in the Sydney Morning Herald and some other news sources today is pretty silly: ‘Red alert as “cork” plugs volcano’. This headline does what such headlines so often do: create a false sense of an urgent, dangerous situation by misrepresenting the facts. That little word ‘as’ is very important in the creation of this effect. There is indeed a red alert at Puyehue-Cordón Caulle, there has been since the eruption began: but by putting the word ‘as’ after the words ‘red alert’ an entirely baseless impression is created that the red alert is the result of whatever situation is described after the ‘as’. By the third word of the headline an expectation of potential disaster is established in the reader’s mind, and s/he is thus pre-disposed to react with alarm and concern to the news that a ‘cork’ is plugging the volcano. The word ‘cork’ itself confirms the impression — everyone knows what corks do, they contain pressure and when they are released an explosion results. This is made explicit in the original AFP story: ‘Geologists said a “cork” of lava, which emerged on Tuesday and was blocking even more lava from spewing forth, had the potential to create a huge build-up in pressure’. The headline rests neatly on that word ‘cork’ in the middle: the words preceding it prepare the reader for danger, the words after it confirm the nature of that danger, and another volcano scare story is set merrily upon its way.

By the time the AFP story has reached Earthweek it has become enveloped in a general air of breathless anxiety, as a standard bulletin from SERNAGEOMIN on the activity of the volcano becomes ‘an urgent warning’ about building pressure and powerful blasts: ‘geologists issued an urgent warning late Wednesday, saying a “cork” of lava had begun to block the volcano’s crater, building up pressure that could lead to another powerful blast’. The bulletins on Puyehue-Cordón Caulle, by the way, are normally released by SERNAGEOMIN around 15:30-16:00 local time, but of course it’s much more exciting to talk of ‘an urgent warning’ issued ‘late Wednesday’ than of ‘a standard bulletin’ issued ‘in the middle of the afternoon, as usual’.

The facts upon which the story is based in no way justify the alarmism of the Australian headlines, still less the utter rubbish from Earthweek. The ‘red alert’, as stated above, was in place anyway, and has not been changed as a result of the current situation. The ‘cork’ plugging the volcano is no big deal. Here’s what SERNAGEOMIN actually reports in its most recent bulletin for Puyehue-Cordón Caulle: ‘the possibility of an explosive event still remains because of possible obstruction of the conduit by the lava erupted and/or changes in the dynamics of the eruption, although there is little likelihood that it will reach the magnitude of the initial eruptive phase’. That is standard wording for a standard situation: the volcano has begun erupting lava, cooled lava may block the conduit creating the circumstances for explosive activity caused by continuing pressure within the volcanic system. This is not a disaster movie scenario, just one that needs careful watching (which is what SERNAGEOMIN is doing).

There is a particularly Australian context to the Sydney Morning Herald‘s daft headline. The flight disruptions caused by ash from Puyehue-Cordón Caulle have given Australia a lot of problems, and it’s understandable that Australian newspapers and their readers are sensitive about volcanic activity — particularly the threat of more explosive activity and more ash. But that’s all the more reason not to over-react, to get the facts right, and not resort to lazy sensationalism.

News
Red alert as ‘cork’ plugs volcanoSydney Morning Herald, 24 June 2011
Red alert as ‘cork’ plugs volcanoThe Age, 24 June 2011
Experts warn Chile volcano could explode again – AFP, 24 June 2011
Chile volcano could explode againHerald Sun, 24 June 2011
Aviation halted for second week by Chile eruption – Earthweek, 24 June 2011

Information
Global Volcanism Program: Puyehue-Cordón Caulle volcanic complex – summary information for the PCCVC (1507-15=)
Servicio Nacional de Geología y Minería – website of Chile’s SERNAGEOMIN
OVDAS-SERNAGEOMIN bulletins for Puyehue-Cordón Caulle – PDF files are available from this page of the OVDAS website

The Volcanism Blog

Nabro eruption: new bulletin from the Eritrean Government 24 June 2011

Posted by admin in activity reports, Africa, Eritrea, eruptions, Nabro.
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The Eritrean Government has issued a new bulletin about the volcanic eruption at Nabro and its aftermath: ‘Government taking close care of nationals affected by earthquake and volcanic eruption’. Text as follows:

Asmara, 22 June 2011 – The Eritrean government is extending the necessary care and assistance through relocating to safe place for nationals displaced due to earthquake and volcanic eruption that occurred in southern and southwestern parts of Southern Red Sea region on the 12th and 14th of June.

The regional Administration disclosed that the Government is working diligently in moving the nationals to safe place in view of the fact that new landscape is being formed due to the eruption resulting in the  melting of rock, in addition to possible health problem due to emission of smoke and dust. The situation is now being stable, it added.

The nationals relocated to safe place said that although there previously existed average earthquakes in the area, this year’s incident was quite strange that evolved into volcanic eruption and the melting of rocks. In this respect, they expressed appreciation to the emergency assistance being provided by the people and that the Government in rescuing their lives and cattle from the natural disaster.

Reports indicated that as a result of the disaster, flow of lava with width up to 1,000 meters and height of 15 meters surfaced in Seriru, southern Denkalia, that destroyed vegetation on about 20 kilometers. As a result of the molting of rocks and the covering up of streams, new landscape is being witnessed.

It is to be recalled that the first volcanic eruption that occurred around Seriru in the extreme south of Southern Red Sea region on June 12 caused 5.7 rector scale earth tremor. The eruption also gave rise to dust that covered hundreds of kilometers and that the tremor was heard in the greater portion of the region, according to reports.

This is the fourth official statement the Eritrean Government has issued about the Nabro eruption. The previous statements were ‘Volcanic eruption witnessed in the tip of Southern Red Sea Region’ (13 June 2011), ‘Inhabitants of Afambo, Nebro and Sirero moved to safer locations’ (16 June 2011) and ‘Volcanic eruption in Southern Red Sea Region creates new landmass’ (21 June 2011).

Information
Global Volcanism Program: Nabro – summary information for Nabro (0201-101)

The Volcanism Blog

A note on comments 24 June 2011

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A small number of highly partisan and very un-volcanological posts have been left here in response to the Nabro eruption: Eritrean politics is clearly a very divisive business. Most of these comments were automatically held for moderation and did not make it through in the end — this affected arguments from both pro- and anti-government sides, so there’s nothing partisan about it. They didn’t get through moderation because they failed to follow one or more of the rules below.

  • Don’t abuse or insult me. This really will get you nowhere.
  • Don’t accuse this blog of being biased, a mouthpiece for one side or the other, racist, imperialist, a front for the CIA, etc. That’s just silly.
  • Don’t assume that just because I quote something, I agree with it.
  • Don’t reference Wikipedia articles. I don’t allow links to that site here. Find a proper source and it’s possible your comment, if it otherwise has merit, will get through.
  • Don’t come here and submit comments using texts provided for you by someone else as part of some campaign or other. When I find four comments in my moderation queue using precisely the same wording I suspect that something funny is going on.

Volcanoes have their political aspects and this blog doesn’t shy away from that. People are welcome to leave comments addressing political issues in Eritrea or anywhere else as long as the connection to matters volcanological is clear and the rules above are followed. Thank you.

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The Daily Volcano Quote: the power of Etna’s lava 23 June 2011

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Among the many eruptions of this volcano, the one in the year 1669, deserves to be recorded. In that year the summit was observed to send forth great quantities of smoke and flame; the top had fallen in, so that the mountain was much lowered; the islands of Vulcan and Stromboli, two volcanoes to the westward of Sicily, were observed to rage more than usual. Eighteen days before the eruption the sky was very thick and dark, with thunder, lightning, frequent concussions of the earth, and dreadful subterraneous bellowings. On the 11th of March, sometime before the lava got vent, a rent was opened in the mountain twelve miles in length, into which, when stones were thrown down they could not be heard to strike the bottom. Burning rocks, 60 palms (15 of our feet) in length, were thrown to the distance of a mile; others of a lesser size were carried three miles off; the internal noises of the mountain were exceedingly dreadful, and the thunder and lightning from the smoke scarce less terrible than they. When the lava get vent, it burst out 20 miles from the crater, and sprung up into the air to a considerable height. Here it formed a mountain of stones and ashes, not less than half a mile perpendicular in height, and three miles in circumference. For 54 days neither sun nor stars had appeared: but soon after the lava got vent, the mountain became very quiet. The terrible effects of this fiery stream may be imagined from its amazing extent; being no less than fourteen miles long and in many places six in breadth. In its course it destroyed the habitations of 30,000 persons; and meeting with a lake four miles in compass, it not only filled it up, though several fathom deep, but made a mountain in place of it. Having reached Catania, it destroyed part of its walls, and ran for a considerable way into the sea, forming a safe and beautiful harbour; which, however, was soon filled up by a fresh torrent of the same inflamed matter.

William Kirk, The Fiery Museum, or the Burning Moutains; Containing Authentic Accounts of those dreadful Eruptions which have so frequently broke out at Mounts Vesuvius and Ætna (Lewes: J. Baxter, 1808), pp. 30-32.

The Daily Volcano Quote: from Monday to Friday, a new eruption of volcanic verbiage each day.

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Nabro eruption: Eritrean opposition appeals for international assistance 23 June 2011

Posted by admin in Africa, Eritrea, eruptions, Nabro.
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Following the Eritrean Government’s statement that seven people were killed in the eruption of Nabro volcano in the south of the country (after initial official claims that there were no fatalities), groups opposed to the current regime in Eritrea have been calling for international assistance for those affected by the eruption. The Sudan Tribune reports today that the Red Sea Afar Democratic Organization (RSADO), an exiled opposition movement based in the Ethiopian capital Addis Ababa, has accused the Eritrean Government of concealing the scale of the disaster, failing to give the affected population warning and assistance, and preventing international aid from entering the country. According to an RSADO spokesman quoted in the report, the Eritrean Government had ‘knowledge in advance’ that the eruption would occur ‘and evacuated hundreds of its soldiers from the area one day ahead of the eruption however [they did not give] advanced notice to the inhabitants nor did [the government] evacuate them to safety’.

The report notes that ‘Independent news about the eruption is hard to come by as Eritrea does not allow independent local journalists or foreign correspondents into the the Red Sea nation’ and that ‘The UN or other NGOs are reportedly not allowed to leave the capital, for independent assessments of the situation of the people’ in Eritrea.

The overall humanitarian situation in the region of Eritrea around Nabro remains unknown, but there are reports of the local population on the Ethiopian side of the border being severely affected by the eruption.

News
Eritrea volcano ash hits Ethiopia villagers – BBC News, 20 June 2011
Eritrean opposition asks for international support as volcano kills sevenSudan Tribune, 23 June 2011

Information
Global Volcanism Program: Nabro – summary information for Nabro (0201-101)

The Volcanism Blog

Smithsonian/USGS Weekly Volcanic Activity Report 15-21 June 2011 23 June 2011

Posted by admin in activity reports, Africa, Batu Tara, Chile, Costa Rica, Egon, Eritrea, eruptions, Etna, Hawaii, Indonesia, Italy, Kamchatka, Karymsky, Kilauea, Nabro, Paluweh, Russia, Shiveluch, Turrialba, United States, Weekly Volcanic Activity Reports.
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The Smithsonian Institution and United States Geological Survey Weekly Volcanic Activity Report, compiled by Sally Kuhn Sennert, has been issued for the week 15-21 June 2011. Some of the highlights:

  • Etna: renewed ash emissions from Bocca Nuova
  • Nabro: eruption continues, with plumes of water vapour and sulphur dioxide
  • Puyehue-Cordón Caulle: a viscous lava flow observed as eruptive activity continues
  • Turrialba: a new crater lake observed at the summit

SI/USGS Weekly Volcanic Activity Report 15-21 June 2011

Click on the map for a larger version (1211 x 784 pixels).

The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 15-21 June 2011 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.

New activity/unrest: Etna (Italy), Nabro (Eritrea), Puyehue-Cordón Caulle (Chile), Turrialba (Costa Rica).

Ongoing activity: Batu Tara (Indonesia), Egon (Indonesia), Karymsky (Russia), Kilauea (Hawaii, USA), Paluweh (Indonesia), Shiveluch (Russia).

Note: ‘a.s.l.’ = ‘above sea level’.

(more…)

The Daily Volcano Quote: uses of a lava flow 22 June 2011

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The large crater of San Salvador volcano contained a crater lake in the early 20th century. However, in June 1917, the lake boiled away in the same week that an earthquake did considerable damage to cities on all sides of the volcano, and lava began to flow from the volcano’s north side … The lava flows destroyed highly productive coffee farms. The black basaltic lava covered about 16km2, which is still devoid of vegetation other than some lichens and occasional grasses. The principal use of the lava flow today is to filter rainwater that supplies San Salvador. A grim use of the area developed in the civil war from 1979 through 1992 as paramilitary squads used the lava flow as their favoured place to dispose of bodies.

Payson Sheets, ‘People and volcanoes in the Zapotitan Valley, El Salvador’, in John Grattan & Robin Torrence (eds.), Living under the Shadow: The Cultural Impacts of Volcanic Eruptions (Walnut Creek, CA: Left Coast Press, 2010), p. 83.

The Daily Volcano Quote: from Monday to Friday, a new eruption of volcanic verbiage each day.

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Images of the Nabro eruption (updated) 22 June 2011

Posted by admin in Africa, Eritrea, eruptions, Nabro, NASA Earth Observatory.
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Just a quick post to draw your attention to some images of the Nabro eruption in Eritrea.

Nabro eruption 01

Nabro eruption 02

Many thanks to Martin Rey, who left a comment at an earlier post giving a link to some screen captures he obtained from local TV station Eri.TV of the Nabro eruption. The pictures seem to show the plume from ground level, lava flows, vegetation on fire, and relief/evacuation operations. Two are reproduced above: the whole set of 23 can be found here: http://picasaweb.google.com/triart3d/NABRO

UPDATE. And here’s the video itself at earthquake-report.com’s cumulative and now immensely long posting on the Nabro eruption, and at YouTube. Chris Rowan talks about the seismic aspect of the eruption at Highly Allocthonous in a very illuminating post on Seismo-volcanism in Eritrea. And for analysis and discussion of what Nabro is up to (and might get up to in the future), check out Erik’s comprehensive and enlightening new post at Eruptions: Speculating on the 2011 Nabro eruption in Eritrea.

Nabro eruption 19 June 2011 (NASA/Terra)

And there’s a fascinating picture of a lava flow from Nabro at the NASA Earth Observatory (above), captured by ASTER on the Terra satellite: Eruption at Nabro volcano.

More on Nabro later, time permitting.

Information
Global Volcanism Program: Nabro – summary information for Nabro (0201-101)

The Volcanism Blog