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Chaitén update, 11 August 2009 (bulletins 101 and 102) 11 August 2009

Posted by admin in activity reports, Chaitén, Chile, eruptions.
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Two new SERNAGEOMIN bulletins on the ongoing eruption at Chaitén to catch up with: no. 101 (PDF), covering 8-15 July 2009, and no. 102 (PDF), covering 16-22 July 2009. Nothing has been made available since, and neither of these bulletins is yet available on the informes page of the Observatorio Volcanológico de los Andes del Sur (OVDAS) website; this inability to provide even the most basic information in a timely manner is all too typical of the way SERNAGEOMIN does things. The PDF links above are to SEGEMAR (Servicio Geológico Minero Argentino), via Werner Luis’s Erupción del volcán Chaiten site.

These two bulletins are, like their immediate predecessors, sketchy and formulaic, and there is no point in providing full translations. Bulletin 101 (8-15 July 2009) reports the eruption column reaching up to 1.2 km above the dome complex, persistent block-and-ash flows indicating continuing growth of the dome particularly in the western part, and stable seismicity with daily averages of 22 hybrid (HB) earthquakes with magnitudes up to 4.2, and 11 with magnitudes of below 3.0. RSAM levels have not exceeded 150,000 units. The conclusion warns of the continuing danger of block-and-ash flows and lahars, and announces the maintenance of Volcanic Red Alert. Bulletin 102 is exactly the same, except that the plumes are reported to be reaching up to 1.5 km above the dome complex, and the daily average of hybrid earthquakes of greater than magnitude 4.0 is given as 20.

The level of information SERNAGEOMIN is providing about the Chaitén eruption is inexcusably inadequate. There has been no overflight since 1 May 2009 , and no new pictures have been released by SERNAGEOMIN since those in bulletin no. 96 of 8 June 2009. Indeed, that bulletin was the last to extend beyond one page. Since then all we have had from SERNAGEOMIN is a sad succession of sketchy one-page bulletins providing the bare minimum of information. For those of us trying to follow the progress of this eruption from elsewhere in the world this is frustrating. For people in Chile itself it must be utterly exasperating.

Here’s what tireless Chaitén-watcher Werner Luis, who has covered the eruption in detail since it began on his Erupción del volcán Chaiten website, had to say on 5 August about SERNAGEOMIN bulletins 101 and 102 (my translation):

How lamentable is this lack of information! As the volcano injects thousands of tons of SO2, CO2, ashes etc. into the atmosphere, profoundly affecting the animal and vegetable life of vast areas of two countries, the economies of entire communities, SERNAGEOMIN merely issues bulletins that appear to be photocopied from previous reports, and now are even reduced to appearing fortnightly…

SERNAGEOMIN is supposed to be a key element in the national volcano monitoring network, Red Nacional de Vigilancia Volcánica (see lavish presentation here in PDF, complete with quote from Winston Churchill), currently being developed by the Chilean Government. Recently the head of that project, Jorge Muñoz, spoke of SERNAGEOMIN’s vital role in providing ‘relevant and accurate knowledge and information to reduce the vulnerability and risk level of [volcanic] phenomena for the population’. Things are going to have to change a lot at SERNAGEOMIN before that aspiration becomes a reality: at the moment it is clear that, so far as informing the public is concerned, they couldn’t care less.

[Thanks to Werner Luis for tracking down bulletins 101 and 102.]

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

Global Volcanism Program: Chaitén – summary information for Chaitén (1508-41)
SERNAGEOMIN – Servicio Nacional de Geología y Minería (Spanish)
Erupción del Volcán Chaitén – extensive coverage of the Chaitén eruption

The Volcanism Blog



1. Bruce - 12 August 2009

Hooray! You’re back!

2. Dan - 12 August 2009

No kidding about the lack of Chaiten info. We’ve had no dome volume or extrusion rate data all year and the last overhead photos are several months old.

3. Miguel V. - 12 August 2009

I agree with all of your remarks. I’ve been myself trying to obtain additional information, but the design of the SERNAGEOMIN’s website is very bad. I sent few complains and suggestions but I got no answer.

As you point out this behavior is inexcusable, given the level of state intervention in the region. Providing accurate and timely information should be one of the priorities of the plan.

My guess is that SERNAGIOMIN is severely understaffed. Their work force was placed under strain during the critical episodes of the eruption and they have now returned their normal duties, which include processing and reviewing mining activities.

It is a pity that a a very geologically active country like Chile counts only with a small office to study these processes.

Cheers & Thanks for your reports

4. Guillermo - 12 August 2009

I agree with Miguel too. That’s the point. The SERNAGEOMIN is not only refered to volcanism, but the rest of the geological activity in Chile, mainly mining. The volcanic monitoring is task of the OVDAS- Observatorio Vulcanológico de los Andes del Sur, dependant of SERNAGEOMIN. There are only a few experts working on it here in Chile.

In the other hand, I’m the one who told Werner Luis of the ‘Erupción…’ page of the SEGEMAR page with the Chaitén reports, that I found after knowing their existence after an authority wrote an article citing them

Bye and my best wishes

5. admin - 12 August 2009

It’s absolutely true that SERNAGEOMIN has limited staff and resources, has responsibilities other than volcano monitoring, and that the lack of serious volcano monitoring in Chile results ultimately from a lack of political will over many years – the politicians are to blame, not the geologists. I tried to put these things in context about a year ago, when I wrote about ‘Volcano monitoring in Chile: the lessons of Chaitén’:


But I also think complacency and bureaucratic inertia within SERNAGEOMIN have a part to play, particularly when in the age of the web it is so easy to make timely information widely available. They could improve matters by redesigning the dreadful OVDAS website, for a start.

6. jm - 14 August 2009

I’ve been wondering whether, if the dome grows sufficiently to fill and then overflow the crater, the removal of the support for the outer layers that currently is provided by the pre-existing bulk of the mountain will result in them falling away and “uncorking” the lava chamber as happened Mt. St. Helens’ when the mountain-side above the bulge slid away?

Is this a valid concern?

Does anyone have any estimate of how large an eruption we might see if that happens?

7. Thomas Donlon - 16 August 2009

Jim, RE: Chaiten,

I don’t know for sure if your concern is valid or not but here are some reasons not to worry about it.

What guides my thinking on this is that there has been many little collapses of the dome debri accumulating at Chaiten – and then there is a temporary doubling of the cloud size as a flank collapses.

The blogger at the site above has carefully watched each puff of the Chaiten volcano on the Chaiten Airport CAM and has often noted such puffs correlating them with other reports of mild flank collapses as the loose, blocky, rubble/debri at the dome grows and sometimes spills down the side of the mountain. I see a lot of the same ahead. The mountain hasn’t really coalesced into a solid unit but is more like a pile of blocky rocks that continually gives way.

And even if there is a Mt. St. Helens size eruption there – it is in a remote area and not people are likely to be directly affected.

So, and I don’t think this is likely, if some massive plug deep inside the volcano plugs up the magma tube there could be a repressurization and massive explosion. However, what is being extruded now is rhyolite, which I think is as tough a magma as there is – and if this isn’t plugging the volcano – probably nothing will.

Now, perhaps there is another magma chamber under/around Chaiten that hasn’t really interacted yet with the hotter magma from deep below and perhaps this other magma chamber comes in contact with the hot, deeper magma, maybe then we could have the making of a massive eruption? I’d rate that scenario of mine also as very unlikely.

Now, and I don’t have the details on this – there has been some hypothesized change of magma that might account for a stronger future eruption. Too tell the truth – I don’t understand how this is supposed to take place.

The most scary scenario regarding Chaiten that I can come up with is that the eruption at Chaiten indicates a general disturbance of deep magma across a wide region and that big eruptions could occur elsewhere in the area. But, I haven’t seen any reports of anything like that.

There is another inflating magma chamber detected by satellite measurements of an inflating area elsewhere in the Andes. This is something to keep watching closely – and maybe this system could lead to an eruption in a few decades – or a thousand years or more.

The area is called Lazufre. A few years ago INSAR detected some accelerating ground deformation in the area.

But the more recent abstract to the report linked above suggests that the ground deformation has been steady and “nearly constant” from 2003-2008 which is better news if you don’t want a massive eruption. Maybe that means the infusion of magma isn’t accelerating too much – and any volcanic activity there could still be decades away.

Still, the science regarding Chaiten isn’t that good right now.
I would guess that there is at least an 80% chance (maybe far higher) that Chaiten won’t transform in our lifetime into anything bigger than we saw from it the past few years. The other 20% chance isn’t based on any known danger it is just deference to the ignorance I have of the volcano.

8. Fresh Bilge » Chaitén Update - 17 August 2009

[…] will recall that the slouches of SERNAGEOMIN have reduced their output of bulletins to one every two weeks. This leaves the webcam as sole […]

9. jm - 19 August 2009

Thomas Donlon, thanks for the info and insights!

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