Ash fall
eklemetti | June 13, 2008
So, this was a bit of a surprise to me. Six weeks into the Chaiten eruption in Chile, apparently the volcano has picked up the tempo again. Not much in the report except that apparently two new vents/craters have opened, there is an increase in ash emission and seismic activity. What this might be is difficult to ascertain from the report, but it could indicate that the volcano might be heading down the road toward a collapse, such as the one previously alluded to by scientist-in-charge Luis Lara. Another report - albeit almost identical to the first - does mention in the headline that the…
eklemetti | June 4, 2008
If you needed any evidence that Chaiten is still erupting quite vigorously, just check out the MODIS image taken on 5/31 (above). The eruptive column is still delivering ash across southern Chile, over the Andes and into Argentina. This eruption just keeps on impressing me with its duration and magnitude - this is one for the ages (well, human ages).
eklemetti | May 30, 2008
We've been hearing a lot of conflicting reports about the state and future of the Chaiten eruption. Now ending its fourth week of eruption, Chaiten was said to be easing up a bit, but recent reports have Luis Lara from the SERNAGEOMIN still worried about a potential collapse, followed by a devastating eruption. I'll have to take his word for it as the explanations in the article don't really make a lot of sense. It sounds like both Lara and Dr. Petrinovic (Argentina) are worried about dome collapse, but that would just form large pyroclastic flows ... unless the dome collapses enough to…
eklemetti | May 29, 2008
This isn't really new activity, but a report on the ongoing activity at Soufriere Hills on Montserrat in the West Indies. Soufriere Hills is a composite volcano that has been erupting for almost 11 years now, producing pyroclastic flows and ash fall that have wiped out entire towns on the island of Montserrat. Most of the activity is caused by dome collapses, where the viscous dacite lavas will erupt to form domes that then become oversteepened and collapsed due to gravity. This material is still hot (usually) and forms the deadly pyroclastic flows. Sounds like there have been a few dome…
eklemetti | May 28, 2008
Some news from the Chaiten eruption. Apparently, LanChile has cancelled some flights around the region of southern Chile due to the ash. They likely implies that the eruption column is bigger than reported by the SERNAGEOMIN on Monday, but the report has little in the way of details. Sounds like the volcano is still huffing and puffing away. Definitely one of the more important and interesting eruptions in the last few hundred years and it has the Cascades Volcano Observatory along with the USGS VDAP buzzing (based on some conversations I've had recently), even almost four weeks in.
eklemetti | May 26, 2008
Tungurahua, one of the most active (and harder to pronounce) volcanoes in the Andes, has been experiencing explosions over the last few days. Not much in the report beyond the 125 explosions, increased seismicity and ashfall around the volcano. This is fairly typical behavior of Tungurahua: Strombolian-style eruptions (see the picture above for a great example) with ash and blocks being ejected from the crater. The volcano has been continuously erupting since 1999.
eklemetti | May 19, 2008
It has been rather quiet on the volcano news front over the weekend. A couple tidbits:
- There are some new data showing the sulfur dioxide flux from Mt. Etna (Italy). The image above is an eruption of Etna from 2001 (and it makes a great wallpaper).
- I've heard very little about Chaiten lately, mostly because I don't think much has changed. The last update provided by the SERNAGEOMIN was on 5.16 (in spanish) and pretty much that is exactly what it says: the volcano continues to erupt. Apparently some USGS folks will be arriving on the scene soon as well. Most of the town of Chaiten has…
eklemetti | May 15, 2008
To keep us up to date on the goings-on at Chaiten in southern Chile, well, the volcano is still erupting! Yes, two weeks in and heavy ash is still being erupted from vent. The latest reports are vague, but Chilean officials are saying things like "There's been additional volcanic activity that we're really worried about..." Now, I can only speculate what this means, but this might be an indicate that the SERNAGEOMIN are really beginning to seriously consider that the whole volcano may collapse.
The town of Chaiten, even without a collapse, is pretty much been wiped off the map. 90% of the…
eklemetti | May 14, 2008
A bit busy today, so to borrow from the newest USGS/SI Volcanism Report:
On 12 May, the plume rose to an altitude of 8 km (26,200 ft) a.s.l.
During an overflight conducted by SERNAGEOMIN, four more plumes of a
similar altitude were generated by explosions and drifted NE. Several
hectares of burned vegetation, likely from pyroclastic flows or
lateral explosions, were noted on the N flank of the dome. Small
pyroclastic flows may also have been responsible for completely burned
forest to areas in the NE, and on the W and NW dome flanks. A lahar
caused the banks of the Chaitén River to overflow…
eklemetti | May 13, 2008
I just read a report that the ash column at Chaiten is beginning to collapse. The SERNAGEOMIN says that the ash column is only 4.5 km tall now, as opposed to the 20 km it had reached earlier. Still, there are not reports of pyroclastic flows, but that could be a matter of hours or days at this point. We'll be keeping a close watch on the eruption to see if this is the beginning of the end, or just a lull in eruptive activity, here a full 12 days into the eruption.
UPDATE 12:20 PM (Pacific Time): According to this new article, the SERNAGEOMIN is reporting the first of the column-collapse…
eklemetti | May 12, 2008Here is a gallery of some ridiculously cool photos from the Chaiten eruption ...
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eklemetti | May 10, 2008
Before we get too far, I wanted to make sure that folks understand that I'm just making educated conjectures on the nature of the eruptions I read about and by no means do I have any extra insight over those scientists on the ground at the eruption. I have a very limited set of data to examine - whatever the media reports - so I am just speculating based on what I know about the eruption style, volcano in question and whatever other variables might come into play. So, please, don't think that I know exactly what is going on or what will happen better than the scientists tackling the volcano…
eklemetti | May 9, 2008
This marks a full week of eruption at Chaiten and the volcano shows no signs of abating.
You have to feel for Luis Lara. He is apparently the pointman for the SERNAGEOMIN in regards to this eruption and really, I think its anybody's guess what might happen next. Heck, we haven't seen many eruptions of this scale - and this out-of-the-blue - since the birth of modern volcanology, so we're testing a lot of hypotheses now. What Dr. Lara says is that the eruption is still going strong, lava flows seem to be occurring at/near the vent but not spilling out of the caldera, the two vents have…
eklemetti | May 8, 2008There are, indeed, other volcanoes erupting right now worldwide other than Chaiten. Of course, when you have an eruption like Chaiten going on, it is hard to pay attention to other eruptions.
Ubinas, Peru
Ubinas, in Peru, has been having intermittent ash eruptions for the past few months, depositing ash on the surround communities. Apparently these eruptions have been causing some respiratory ailments to the local Peruvians due to the ash & volcanic gases. Ubinas is one of the most active volcanoes in Peru. This picture shows Ubinas erupting in 2006, as captured from the International…
eklemetti | May 8, 2008
Another day, another development at Chaiten. Military stationed near the volcano helping with evacuations reported "booming noises" and saw incandescent blocks getting hurled from the vent area. This suggests that lava is at the surface and potentially that the edifice itself is beginning to crack/strain from the loss of material from the eruption. Remember, when you erupt all this volcanic material, you leave a void under the volcano where that magma used to be, so suddenly you have a volcano with no foundation. Sometimes they can founder into that space, forming a caldera. We already…
eklemetti | May 7, 2008
The eruption at Chaiten has now begun to have widescale effects on the region of Patagonia, beyond the ashfall. Air travel has been disrupted due to the amount of ash in the air. It is well-documented that ash posed a significant hazard to aircraft, so this seems like a wise move on the parts of Argentina and Chile.Â
Not much else new to report beyond that the fact that this eruption is now into day 6 without any signs of letting up. Impressive to say the least.
eklemetti | May 6, 2008NASA captured this great image of the ash plume from Chaiten, which has reached 15-km into the atmosphere.
Following this eruption, I'm sure there will be a lot of work into why no one had any clue an eruption of this magnitude was about to occur.
eklemetti | May 6, 2008
Well, this is getting rather harrowing. Volcan Chaiten, the Chilean volcano that sprung back to life last Friday after anywhere between 2,000 to 7,000 of quiet, is apparently erupting lava along with ash now. Sounds like its a good rhyolite/rhyodacite lava based on the description: "very small and very thick and as such was moving slowly so it is moving very slowly''.
Chilean officials are now fearing that the volcano is in "worst case scenario"Â mode - although, they never mention what that might be: full-on caldera? topography-erasing ignimbrite? Pinatubo-scale eruption? However, the…
eklemetti | May 5, 2008Monsters and Critics has some truly fabulous images of the ongoing eruption at Chaiten in Chile.
The pictures of the extent of ash fall are quite remarkable. It is hard to tell exactly how deep the ash is or how far from the vent these pictures were taken, but one can imagine that if a helicopter took them, then they are relatively far from the action. The Chilean President, Michelle Bachelet, toured the area to see the damage. Stunning stuff.
eklemetti | May 4, 2008
Update 5/4/08: Looks like there is now officially a deathtoll for Chaiten, as an elderly woman died during the evacuations. The volcanoes continues to spew ash and I wouldn't be surprised if it did so for at least a few more days. There have also been reports of a sharp increase in earthquakes in the area since the eruption. Now, before everyone goes nuts, this could be just a response to the dramatic release of pressure caused by the eruption, possibly faulting in the caldera walls activated by the eruption, or possibly magma working its way to the surface as the eruption progresses.…