Extremophiles, Volcanoes and You


Folks have been suggesting that life on Earth started near volcanic vents for a long time now (and of course, some people don’t buy it). Whether or not life sprung forth near hydrothermal vents, undersea black smokers or from the head of Zeus, it doesn’t really change the fact that we find organisms living in these places today, expanding what we might consider “habitable” by leaps and bounds. Case and point, researchers from CU-Boulder have recently found a community of micro-organisms happily living near the summit of Volcán Socompa (above) in Chile in the hydrothermal vents. Now, having done field work in the high Andes of Chile (at Volcán Aucanquilcha – say that three times fast), I can attest to the fact that it is as close to working on Mars as you might be able to get on Earth – dry, desolution, mostly lifeless, extreme day/night temperature variations, thin air, the whole nine yards. So, to find these communities shows just how hardy life can be when presented with challenges.
One interesting question not brought up in the article is how quickly might these communities develop. Socompa was last known to have erupted in 5250 B.C. (most likely). This might limit the amount of time for these micro-organisms to take a foothold at the summit of the volcano to at most ~7,000 years. This seems like a pretty reasonable time for life to reemerge after an eruption – the question would be from where did it arrive in a place as desolate as the high Andes of Chile after the eruption. Of course, this also begs the question of whether life like this could exist of Mars, but that is question best left untouched by me. To me, this is just another example of how no matter how destruction we think volcanoes are, life just keeps on coming back for more.
{Hat tip to reader Thomas Donlon for pointing this out to me.}

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Concern lingers, angers flare at Chaiten


The people who remain in Chaiten face the potential for a devasting pyroclastic flow, so says Jorge Muñoz of the SERNAGEOMIN in Chile. The volcano is still producing large ash columns on Tuesday and a flyover of the dome forming inside the caldera has lead to the concern that a collapse on a larger scale than those seen last week could wipe out the town for good.
The government hopes news like this from volcanologists might convince the last remaining residents of Chaiten to leave, but no indication of this has come to pass. In fact, things sound like they’re getting heated in the fight over the town of Chaiten. The Minister of Government Affairs had this to say to the lawyers for the remaining residents:

“I think that up until now, we have been quite convincing, but to say that the problem is to unblock the river (…) Why don’t we back up a bit? Why is the river overflowing? Because the volcano is exploding, that’s why!”

It gets even uglier here from the Undersecretary of the Interior. It seems that both sides are digging in the heels, so to speak.

A review of ash cloud classification

Jonathan Castro has reminded me that I need a refresher on the proper terminology for ash columns related to volcanic eruptions. It is very easy to start mincing words and using them inappropriately – and that is the sort of sloppy reporting and discussion I am trying to avoid.

So, to refresh my (and our) memory on ash clouds and how to classify them, we can go back to one of the indispensable textbooks on volcanology, Cas and Wright’s Volcanic Successions. The classification scheme they provide is summarized in the figure above. It shows the heights of various eruption columns and the relationship between types of eruptions and their “explosiveness”. Jonathan is likely correct in classifying this eruption in the vulcanian range (<20 km ash column), especially if it was driven by explosions in the dome. If anything, Chaiten’s activity today could be sub-plinian, but a true plinian eruption requires a taller ash column height and higher levels of explosivity.
UPDATE 2/20/2009: Here is a link to an article that talks about the processes that go along with each eruptive style. Remember, the ash column nomenclature is not solely dependent on height, but also process and composition. {Thanks to Boris for reminding me to emphasize this.}

Chaiten Redux


UPDATE 2/19/2009 9:45 AM: Well, it seems that my hunch was at least partially right. Reuters (and Paula Narvaez, special envoy to the Chilean president) is calling the eruption as result of “what appeared to be a partial collapse of its cone.” So, we might have seen the oversteepening of the dome growing in the Chaiten caldera that lead to a collapse, producing (likely) a pyroclastic flow and either an accompanying plinian eruption as the pressure was released or an ash column associated with the pyroclastic flow itself. Now, I might not take Reuters word for it, but it makes sense considering the suddenness of the event.
10:00 AM: More details for Reuters, including the ominous “Our security team have observed an increase in the size of a column of ash and smoke, with a deformation to one side” from the Deputy Interior Minister. My guess is he is referring to deformation on the ash column, not the volcano.
4:00 PM: From a Newsday article, just some more details on the ash dispersal: “On Thursday, increased seismic activity was reported and ash fell 100 miles (160 kilometers) away in Futaleufu.”

Eruptions reader Brian Owens has pointed out that fellow volcano follower, the Volcanism Blog, is reporting that Chaiten is experience a major rejuvenation today.
Sure enough, the Associated Press also reporting that an explosion has occurred in the main dome of Chaiten that has been built since last May and that material is moving downslope from the explosion. There is no clear word what type of volcanigenic material this might be – pyroclastic flow, lahars, avalanche – but there is a major fear that it could block the river and cause flooding in the town of Chaiten. The few citizens left in the area are being evacuated. The Patagonia Times adds that the eruption started around 11 A.M. (local time) and ash has spread across much of the region.
From what I can gather, this seems like it might have been either a dome collapse that was quickly followed by an explosion (possibly caused by the release of pressure from the collapse) or some “burp” of gas-rich magma erupting. The reports of “a massive column of ash” are interesting as this could suggest a true new flux of magma, but it is hard to tell at this point how widespread is the ash and how tall the column might be. At this point, it is all conjecture, but it sounds like Chaiten might be making a comeback. The questions woulds be how big and for how long.
I’ll update as we find out more …

Chaiten update for 2009


It is hard to believe that the eruption at seem to come out of nowhere at Chaiten started over 8 months ago now, and apparently is still not showing many signs of abating. I did get a chance to see some great talks and posters at AGU last month about the Chaiten eruption, with the key points I took away being that Chaiten is erupting a very crystal poor rhyolite (<1% crystals) and that it seems that the source of the magma is relatively deep in the Andean crust. Also, there are some indications that the eruption at Chaiten may have been tectonically instigated – i.e., that earthquakes in the area might have helped the magma to erupt – at least that is what Luis Lara of the SERNAGEOMIN believes (hat tip to Thomas Donlon for the link). The eruption at Chaiten also wreaked more havoc on aviation in South America than we thought, effecting airports 1000s of kilometers away and almost bringing down a number of aircraft. Most everyone I talked to seems to think what we are seeing is very similar to what happened at Little Glass Mountain in California about 1,000 years ago.
Moreover, the eruption hasn’t really stopped since it began in May of 2008. In fact, just last week we saw a collapse of part of the new dome that have produced some pyroclastic flows within and outside the caldera (see above and the Volcanism Blog) and fed more ash into the choked rivers near the volcano. It is anyone’s guess (well, at least at AGU) how long this eruption might go on – weeks? months? years? – but the consensus is that this might be a once-in-a-lifetime eruption (but we already knew that, didn’t we?)

Is Yellowstone making plans for 2009?


2008 is almost finished and we’ve seen one of the few high-silica rhyolite eruptions in the past 100 years at Chaiten in Chile. Chaiten was definitely not high on the list of potential locations for a rhyolite eruption worldwide. However, Yellowstone Caldera in Wyoming definitely is high of the list because it has erupted a lot of rhyolite over the last few 100,000 years (even discounting the big so-called “supervolcano” eruptions).
This is why the current news of an earthquake swarm at Yellowstone is, in the very least, really interesting. The earthquakes – over 250 of them – started yesterday and many of them were as high as magnitude 3.8 on the Richter Scale. The earthquakes are centered under Yellowstone Lake and the depth is poor constrained according to the USGS, but they appear to be shallow. Even Yellowstone expert Robert Smith (Univ. of Utah) say the swarm is “very unusual”. However, YVO plays down the event. The earthquakes might be related to hydrothermal fluids moving in the crust, they might be tectonic or they might be magma moving (but not to the surface). Definitely gives us something to keep an eye on as 2009 begins.
{Hat tip to reader Doug for pointing this out.}

Another tidbit from AGU…

I was chatting with a fellow from AVO and he called the simultaneous eruptions of Kasatochi, Cleveland and Okmok a “once in a millennia” event. So, enjoy it!
He also mentioned that the Kasatochi eruption released the most sulfur dioxide into the atmosphere since the 1991 Pinatubo eruption … but we had an idea of that already.
And who knew that there has been uplift at Uturuncu in Bolivia? I sure didn’t, but Steve Sparks does.
 
More to come later this week when I can go to all the Chaiten posters.

The volcano-earthquake connection?


The BBC is reporting today on a study published in Earth and Planetary Science Letters that attempts to establish a connection between large earthquakes and subsequent volcanic eruptions. The study is focussed on large Chilean earthquakes over the last 200 years (Chile has had some of the biggest, hitting M9 on the Richter Scale) and then examining the number of volcanic eruptions that followed. They find that activity increased in the year after the earthquakes. This suggests that many volcanoes might be “primed” to erupt and just need a catalyst like a large seismic event to promote eruption.
This effect was seen as far as 500 km from the epicenter of the earthquake, which makes for some fascinating speculations for future volcano predictions. For instance, what happens when we have the next big Cascadia subduction zone earthquake in the Pacific northwest? The last major one was in 1700 (and yes, if you read Fire Mountains of the West, it does seem like the Cascades were much more active in the 18th and 19th centuries), so when the next one rolls around, might we expect more activity from the many potentially active Cascade volcanoes. The key to understanding this will be to discover what exactly does it mean for a volcano to be “primed” for eruption – in other words, where does the magma have to be in the system, what thermal condition should the magma be in, what amount of melt has to be present, how degassed can the magma be, how close to the epicenter is the volcano, what sort of shaking did it experience? These are just the first few questions that popped into my head concerning this connection. As usual, more work needs to be done to understand how robust this volcano-earthquake connection might be and how might it work.

Eruptions Mailbag


So, I get a steady diet of email messages here at the Eruptions HQ, so I thought I could try a little roundup of the great information/links that you readers are sending (and I apologize for taking so long for some of these). Enjoy!
– Tim Stone tells us about GeoEye pictures of volcanoes. GeoEye is the new satellite launched to add to the Google Earth images of the planet. There are some quite striking images of volcanoes included in the collection.
– Richard Roscoe sends us to some updated images of the on-going volcanic activity on Montserrat. As usual, there is an abundance of excellent images and information on this Photovolcanica page.
– Dan Cerveny points us to the preview of a new TV show that talks about the current eruption at Chaiten in Chile. In Harm’s Way (on the CW) is about dangerous professions (volcanologists are always assured of a place on that list) and episode 106 featured John Seach quest for pieces of the volcano. Not sure when it might air again, but I’m sure it will pop up on reruns (or online).
Keep the emails coming!

Southern Chile says it is ready for your visit


It has been awhile since we’ve talked of Chaiten, so I thought I’d touch upon “the eruption of 2008” (really, no one else is close). Spring time has arrived in southern Chile, and the Patagonia area has cleaned up a lot of the ash from the eruption (but not the town of Chaiten). National Tourism Service says that most towns and parks in the region are ready for tourists and even some tourist companies near Chaiten are good to go.
As for the volcano itself, the latest USGS update reports ash columns still being erupted and reaching up to 12,000 ft (3,700 meters), along with a “thermal anomaly” in the vent area – likely lava at the dome or near the surface – detected via satellite.