Everywhere … were attestations to Popocatepetl’s presence and antiquity. And here the damn thing was again! Why were there volcanic eruptions? People pretended not to know. Because, they might suggest tentatively, under the rocks beneath the surface of the earth, steam, its pressure constantly rising, was generated; because the rocks and the water, decomposing, formed gases, which combined with molten material from below; because the watery rocks near the surface were unable to restrain the growing complex of pressures, and the whole mass exploded; the lava flooded out, the gases escaped, and there was your eruption. - But not your explanation. No, the whole thing was a complete mystery still. In movies of eruptions people were always seen standing in the mist of the encroaching flood, delighted by it. Walls fell over, churches collapsed, whole families moved away their possessions in a panic, but there were always these people, jumping about between the streams of molten lava, smoking cigarettes …

Malcolm Lowry, Under the Volcano (1947; London: Penguin, 1962), pp. 241-2.

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

The latest Chaitén updates have arrived in my inbox since yesterday, but I haven’t had a chance to check them until now. This information has not yet been published on the SERNAGEOMIN website. Alan Sullivan has already published his thoughts on the latest information, and commented here on an earlier post.

SERNAGEOMIN reports that from 25 to 28 June visual observations of the volcano have been impossible because of the bad weather. The heavy rains have produced flooding and lahars in the watercourses around the volcano, particularly the Chaitén and Amarillo rivers (there have been some news stories in the Chilean press over the past few days reporting on the new flooding of Chaitén town - I’ll catch up with these, and other relevant stories, tomorrow).

There has also been an interesting rise in seismic activity over 27 and 28 June, with up to 5 VT-type earthquakes per hour, and an average of 115 earthquakes per day. Of these, between 25 and 30 earthquakes per day exceed magnitude 2. No HB or LP type earthquakes have been detected. The VT earthquakes were located west and southwest of the volcanic caldera, at a distance of less than 10km from the volcano (in other words, they were between the volcano and Chaitén town). SERNAGEOMIN hedges its bets somewhat as to the meaning of this seismic activity:

In part, the reported seismic activity may be related to the activation of geological faults in the vicinity of the volcano. The location of the earthquakes (less than 10km from the volcano) suggests that the more major seismic activity may caused by the rupturing of rocks and the movement of fluids at depth, in the lower part of the upper system of the volcano. In any case, there has been no confirmation of a new injection of magma at depth and/or a pressurization of the upper system.

SERNAGEOMIN is maintaining volcanic red alert.

Skies have been clearer over Chaitén today and the north-facing webcam at the airfield has been giving some good views of the eruption plume. This image is from 16:16 local time today and shows the late afternoon sun gilding a low plume that is trailing away to the north-east.

For all our Chaitén coverage: Chaitén << The Volcanism Blog

Information
Global Volcanism Program: Chaitén - summary information for Chaitén (1508-41)
ONEMI, Oficina Nacional de Emergencia - Chilean government emergencies office (Spanish)
SERNAGEOMIN - Servicio Nacional de Geología y Minería (Spanish)

On the left, area without vog; on the right, same area with vog. Image: Hawaiian Volcano Observatory.

As Kilauea continues to pump out large quantities of sulphur dioxide and Hawaiian politicians meet to talk about the problem of vog, the Hawaiian Volcano Observatory have put together a timely new page providing extensive information about sulfur dioxide emissions, vog, volcanic ash, and air quality.

Hawaiian Volcano Observatory: sulfur dioxide, vog and volcanic ash FAQ

For all our Kilauea coverage: Kilauea << The Volcanism Blog.

Information
Global Volcanism Program: Kilauea - summary information for Kilauea (1302-01-)
USGS Hawaiian Volcano Observatory - main page for the HVO
HVO Kilauea Status Page - the latest activity reports for Kilauea

SERNAGEOMIN have published a new bulletin on activity at Chaitén volcano, dated 27 June 2008. Translation as follows:

27.06.2008 SERNAGEOMIN bulletin regarding Chaitén volcano

It was not possible to take observations of the Chaitén volcano on 26 June because of the bad weather prevalent in the area.

Seismic data supplied by the PUMA and STBA stations showed stability in the number of type VT [volcano tectonic] earthquakes, which in the past days amounted to about 50 earthquakes per day, averaging about 2 per hour, in general, with magnitudes of less than 2. However, on 25 June four earthquakes were recorded that exceeded a magnitude of 2.

According to the data, seismicity continues to be concentrated under the volcano. No earthquakes of type LP [long period] or type HB [hybrid] have been detected. This, with the presence of open emission centres and continuous degassing, indicates that there has been no repressurization of the system, as described in previous bulletins.

Despite the foregoing, it is important to consider that, during periods of heavy rains, it is probable that there will be a continuation of the occurrence of lahars in the main channels near the volcano. Additionally, accumulations of rocks and ashes in the bottom of caldera-type depression, associated with the growth of the new dome, could produce blockages, the collapse of which could cause new floods of the Chaiten river.

On the other hand, there remains the probable collapse of the old dome and the subsequent generation of pyroclastic flows associated with this process.

There have been no Volcanic Ash Advisories from Buenos Aires VAAC since 1820UTC on 25 June, when ‘continuous emission’ was reported but at too low an altitude to bother aviators. Aviation Color Code was ‘unknown’.

For all our Chaitén coverage: Chaitén << The Volcanism Blog

Information
Global Volcanism Program: Chaitén - summary information for Chaitén (1508-41)
ONEMI, Oficina Nacional de Emergencia - Chilean government emergencies office (Spanish)
SERNAGEOMIN - Servicio Nacional de Geología y Minería (Spanish)

A team of researchers has discovered evidence of explosive volcanism 4km down on the Arctic Ocean seabed, challenging established notions of the nature of volcanic activity at great ocean depths.

The research team, led by scientists from the Woods Hole Oceanographic Institution, found jagged, glassy rock fragments spread out across a 10km² area around a series of small volcanic cones along the Gakkel Ridge, part of the spreading mid-ocean ridge system beneath the Arctic ice. ‘These are the first pyroclastic deposits we’ve ever found in such deep water, at oppressive pressures that inhibit the formation of steam, and many people thought this was not possible’, said Woods Hole geophysicist Rob Reves-Sohn.

A paper detailing the findings of the Arctic Gakkel Vents Expedition is published in the 26 June 2008 issue of Nature.

Information
Global Volcanism Program: East Gakkel Ridge volcanoes - summary information for the Gakkel Ridge volcanoes, excitingly dubbed ‘unnamed’ by the GVP

News
Under ice - Science News, 25 June 2008
Deep-sea volcanism on the Gakkel Ridge - Nature, 26 June 2008 (editor’s summary)
Geologists discover signs of volcanoes blowing their tops in the deep ocean - Innovations Report, 27 June 2008
Fire under the ice - EurekAlert, 27 June 2008

There is no country in the known world where volcanic eruptions have been so numerous as in Iceland, or have been spread over so large a surface. No part of the island is wholly free from the marks of volcanic agency; and it may be truly called the abode of subterraneous heat … it appears that the force of subterraneous fire has been exerted upon every part of this extensive island; and when we consider the eruptions that have been seen at a distance in the sea, we are safe in estimating, that, in this part of the earth, one continued surface of not less than sixty thousand miles has been subjected to that engine of destruction.

‘Description of Hekla’, from E. Polehampton & J. M. Good (eds.), The Gallery of Nature and Art; or, A Tour Through Creation and Science (London, 6 vols., 1818), vol. I, pp. 257-8.

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

In El Mostrador today there is a lengthy report of Chilean President Michelle Bachelet’s statements at the Third Extraordinary Congress of the Asociación Chilena de Municipalidades, held in Puerto Montt. Asked about the future of Chaitén, the President surprised no-one by saying that no decisions had been taken:

Each volcano has a manner of developing that makes it impossible to predict their behaviour … Today there is no possibility of a definite answer, while we do not know what is happening with the volcano … we are not able, not just the Government, no-one, to say today what will happen with the volcano and what will happen with the risks … it is evident that the solutions [for Chaitén] are either rehabilitation or relocation, but I think that it would hardly be serious today for me to make any judgement or decision in this regard.

In its report, La Nación interprets President Bachelet’s comments as ‘indicating to the inhabitants [of Chaitén] that the repopulation of the area is going to be postponed indefinitely’.

El Mostrador also quotes the President’s assertion that the Government’s prompt decision to evacuate Chaitén had been proven correct by the course of subsequent events: ‘What has happened over these days, the degree of flooding and destruction … has demonstrated the justice of a decision that was, centrally, seeking to ensure the safety of the people’. The President also explained the rationale behind the work currently going on in and around Chaitén. The work on local roads, bridges and drainage channels being carried out by the Military Corps of Labour and the Ministry of Public Works is, she said, aimed at ‘mitigating an even greater destruction’.

At one and the same time the Government says no decision has been taken on the future of Chaitén, carries out works in Chaitén which only make sense if the town is to be restored on the same site, declares that no return to the town will be possible for two years, and announces that the behaviour of the volcano cannot be predicted making any timetable for a return to Chaitén that may (or may not) happen, indeed making any decision at all, impossible. Meanwhile the mayor of Chaitén assures his people that they will return to their town regardless, and the intendente of Los Lagos region plans for the restored Chaitén to be ‘the Venice of Chile’ and tells the Minister of Public Works, who describes the town as ‘wrecked’, that he doesn’t know what he’s talking about.

It’s little wonder that some chaiteninos felt driven to greet their President’s visit to Puerto Montt with a vigorous public protest.

Meanwhile the Government has announced that local elections in Chaitén will go ahead as scheduled in October, despite the devastation of the town and the conversion of its population into refugees. The town’s alcalde (mayor), José Miguel Fritis has made clear his disagreement with this decision, telling El Mercurio that a democractic election ‘will not be possible under these conditions’. A political independent himself, he views with suspicion the Government’s decision to hold an election at a time when the vast majority of the electorate are entirely dependent on hand-outs from that same Government: ‘I believe that the people would have very little independence in the vote’. Furthermore, and perhaps more reasonably, he argues that it is inappropriate to expect that ‘a person who is in the most absolute uncertainty about returning to live in the city should be electing their alcalde for the next four years’.

The first group of fifty people from Chaitén returned to the town on Wednesday to view their houses and recover some belongings. The second group was due to visit today, but that operation has been postponed because of bad weather.

For all our Chaitén coverage: Chaitén << The Volcanism Blog

News
Bachelet dice que el comportamiento del volcán Chaitén es impredecible - La Mostrador, 26 June 2008 (Spanish)
Bachelet reafirma que Chaitén no puede ser habitada en el corto plazo - La Nación, 26 June 2008 (Spanish)
Protestas de chaiteninos y estudiantes reciben a la Presidenta en Puerto Montt - El Mercurio, 26 June 2008 (Spanish)
Chile: chaiteninos y estudiantes protestaron contra Bachelet en Puerto Montt - Radio Universidad de Chile, 26 June 2008 (Spanish)
Alcalde se opone a realizar elecciones municipales este año en Chaitén - El Mercurio, 26 June 2008 (Spanish)
50 personas llegaron a Chaitén para recuperar pertenencias - 123 Chile, 25 June 2008 (Spanish)

SERNAGEOMIN have published a new bulletin on the eruption at Chaitén, dated 26 June 2008. Translation as follows:

26.06.2008 Eruptive activity of Chaitén volcano

During 23, 24 and 25 June, because of bad weather conditions prevalent in the area, it was not possible to observe the volcano.

Although the number of earthquakes per day has remained stable some of them have increased in magnituded. While the majority have been located under the volcanic caldera, the epicentres of the earthquakes of greater magnitude have been concentrated 2 or 3km east of the caldera, over one of the lines of the Liquiñe-Ofqui Fault.

Moreover, at noon on 25 June Queilen suffered a prolonged power cut, and once the UPS [i.e. battery back-up power unit] stopped working, several hours of seismic records were lost. However, taking into account the data acquired up to the evening of 24 June and the morning of 25 June, a slight increase in the number of earthquakes with [greater] magnitudes could be seen.

In effect, from 00:00 to 12:00 on Wednesday 35 VT [volcano tectonic] earthquakes were counted, four of which had magnitudes of over 2.2, which are considered to be related to the internal adjustment of the system. No type LP [long period] and/or HB [hybrid] earthquakes, which indicate a new pressurization of the system, have been recorded.

Finally, and as stated in previous reports, there is still a slight but steady growth in the dome, generated by a continuous emission of lava, the latter associated with emissions of gases and ash from the southern flank of the dome.

SERNAGEOMIN maintains Volcanic Red Alert.

The bulletin is accompanied by two not particularly relevant pictures of the lava dome, taken on 4 and 6 June.

For all our Chaitén coverage: Chaitén << The Volcanism Blog

The whole table-land of the province of Quito has always been considered by me as a great volcanic area. Tungurahua, Cotopaxi, Pichincha, with their craters, are only different openings of this area. If volcanism, in the broadest sense of the word, marks all the appearances which depend on the reaction of the interior of a planet on its oxydized surface, this part of the high land is more exposed than any other in the tropical region of South America, to the effect of this volcanism. The volcanic powers rage also, under the domes of augite-porphyry, which, like that of Chimborazo, have no crater. Three days after our expedition we heard, in New Riobamba, at one o’clock A.M., a raging subterranean crash (bramido) that was accompanied by no concussion. Three hours later, there followed a violent earthquake, without any preceding noise. Similar bramidos, coming, as it is supposed, from Chimborazo, were perceived some days before at Calpi. Nearer to this mountain-Colossus, in the village of San Juan, they are extremely frequent. They excite the attention of the natives no more, than distant thunder out of a deeply-clouded sky does in our northern zone.

Alexander von Humboldt, ‘On Two Attempts to ascend Chimborazo’, The New Edinburgh Philosophical Journal, vol. XXIII (April-October 1837), pp. 291-312, here p. 311.

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

From Russia comes news that Russian and US volcanologists are to join forces to study Bezymianny, one of the many active volcanoes of the Kamchatka Peninsula. The principal hazard posed by eruptive activity at Bezymianny is to aviation. KVERT, the organization that monitors the Kamchatka volcanoes, summarizes its hazards thus:

Moderate potential hazards are caused by ash plumes, ash falls, pyroclastic flows, hot avalanches and lahars. The volcano constitutes a potential hazard to international and local airlines at Kamchatka because its eruptive clouds can rise to a height of 8-15 km ASL and extend for hundreds of kilometers from the volcano to different directions.

In a project lasting several years, the Russian/US team will be installing modern seismic and other monitoring networks and probing the volcano’s eruptive processes. The project involves scientists from the Russian Institute of Volcanology and Seismology and the University of Alaska-Fairbanks.

Bezymianny was thought to be extinct until a violent eruption in 1955-6 proved otherwise. On 30 March 1956 an explosive eruption notably similar to that of Mount St Helens in 1980 took place: the upper 180m of the volcano was blown apart, leaving a crater 1.5km in width and projecting an eruption cloud to the east to a height of 40km, at an angle of between 30 and 40 degrees to the horizon. Trees were felled by the directed blast for 24km, and mudflows choked the Kamchatka River. Since then there has been lava-dome growth at Bezymianny, with intermittent explosive eruptions once or twice each year. The RIA-Novosti news agency observes that the 1955-6 eruption of Bezymianny had a profound impact on volcano awareness in the USSR (as it then was), and resulted in the establishment of permanent volcano monitoring stations and the institution of a Soviet Day of Volcanology on 30 March each year.*

[* Thanks to AS for her Russian translations.]

Information
Global Volcanism Program: Bezymianny - summary information for Bezymianny (1000-25=)
Bezymianny volcano - information from KVERT

News
Most dangerous volcano of Kamchatka to be studied - Russia-InfoCentre, 26 June 2008
Вулканологи исследуют самый опасный вулкан Камчатки - RIA-Novosti, 24 June 2008 (Russian)*