Friday Flotsam: Yellowstone slows down, Pakistan eruption clues, NASA images and "Volcano Hell"

News!


Pakistan is home to the world's tallest mud volcano in the region of Balochistan - and its somewhat near the reports of an "eruption" earlier this week.

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Sally Sennert from the Smithsonian Institution sent me an email to say that this week's USGS/Smithsonian Institute Weekly Volcanic Report will be delayed due to the inclement weather in the Washington DC area. She can't connect with the server, so the report can't be updated on the Smithsonian…
The final part of Etna Week, brought to us by guest blogger Dr. Boris Behncke. Check out Part 1 and Part 2 as well! Etna Volcanic hazards By guest blogger Dr. Boris Behncke. Etna is one of the most active volcanoes on Earth, and a population of nearly one million people dwell on its flanks, many in…
A bit of news for your last Monday in September: Pumice deposits from the ~13,000 year old Laacher See eruption. Image by Erik Klemetti, taken in August 2007. More press for Dr. Joyce and his campaign to make the people of Australia terrified that volcanoes will destroy them. He warns of "new…

Yep I knew it would be on the air one of these days but haven't yet seen the bit (waiting for Discovery to send me the DVD). It's about the big sector collapse on Etna's eastern side about 8000 years ago - that was indeed something we would not want to see today, and it might have lesser global impact than a new caldera-forming eruption at Yellowstone but it would hit much more densely populated areas. It was like the collapse of Mount St. Helens in 1980 but about 10 times bigger, and the debris avalanche went into the Ionian Sea, producing a massive tsunami.
Guess what, nobody is worried about a repetition here - although we're seeing signficant displacements on Etna's eastern flank, which have accelerated since 2002. But after all, the sector collapse is once more a worst-case scenario and therefore the least likely to happen. And something similar is happening - at a much grander scale - at Kilauea, and it seems that these basaltic volcanoes have a capacity of "buffering" such flank instability induced mass movements much more efficiently than stratovolcanoes such as Mount St. Helens, Augustine, and an incredible number of further volcanoes that have undergone (and will again undergo) catastrophic sector collapse.
Fun though that both of us - Dr. Erik Klemetti and I - have been through the Discovery publicity machine these days. By the way, the article that Randall Nix refers to in comment #31 in the caldera post (http://scienceblogs.com/eruptions/2010/02/the_structure_of_calderas.php) is not so bad after all - most of all because differently from some of the news media, it says the right thing. There is no serious concern about Yellowstone for the moment; a volcano that's going to "super"-erupt soon would look and behave VERY differently, of that we can be sure. But that would be the matter for another comment, once the burden of apocalypse obsessed once more goes beyond a certain threshold.

Right now in the Mid-Atlantic US the "apocalypse obsessed" are fixated on a snowstorm ;)
An actual threat for a potential tragedy of course is Nyiragongo. We can only hope that some means of alert and evacuation has been prepared for the residents in the area, but with the lack of fund and political instability in the region I fear that is not the case.

Boris I am sorry I know you are the expert but are you saying you agree with the guy who wrote the Discovery News story.....do you really think an eruption at Yellowstone might be cool and that if we are lucky we might get to see one just to shut "people" like me up? I quote from the story:

"A dome eruption (kind of like toothpaste squeezing out of the planet more than an "eruption" like you might picture it) would be cool in that it would add to Yellowstone's unique, ever-changing landscape.

If we're lucky, it might even convince some of the people waiting for the end of days to come roaring forth from Yellowstone Caldera that they're wasting their time."
Sorry but I couldn't get this to post with the link to the Discovery News story but those are quotes from it.

According to the paper I posted on the site yesterday:
Mushy magma beneath Yellowstone caltech.edu [PDF]
R Chu, DV Helmberger, D Sun, JM ⦠- Geophys. Res. â¦, 2010 - mh-gps-p1.caltech.edu
HTML Version
http://74.125.155.132/scholar?q=cache:Y9JjMTR4_tsJ:scholar.google.com/+…
PDF Version
http://mh-gps-p1.caltech.edu/~jackson/pdf/Chu_2009GL041656.pdf
The previous measurements of the magma chamber were not correct. The magma chamber was found to be 4300km3 in volume and more importantly with 32% melt saturated with 8% water plus CO2 by volume. In other words the magma chamber has much more of an explosive potential than was previously thought. Like I said you are the expert so if I am reading this paper wrong please enlighten me.

I took this from the YVO site:
"One way to think about a magma chamber or magma body is to picture a water-filled sponge. The sponge would represent the solid rock whereas the water would represent the melt. Beneath Yellowstone, on average, the magma is about 90% solid rock (like a hot sponge) containing 10% liquid rock in its pores. "

"scientists estimate that the melt part could be about 10% of the low velocity volume or about 1,500-2,000 cubic km."

The YVO better start looking at this thing a little differently in light of the most recent mesurments. Even if this swarm stops there is still a BIG reason to more concerned than we were before this study was published.

By Randall Nix (not verified) on 05 Feb 2010 #permalink

@Randall: I agree the analogy of tooth paste oozing out of the ground can be a bit misleading. Even if it behaved that way it still would not be something you would want to be close to. Kilauea is like that. Most of the time the lava oozes out, but it can explode on occasion. I don't think Boris takes any volcano lightly, either. I have known Boris since the mid 90's and he takes his job and volcanoes very seriously. He knows what he is talking about, as does Erik. Of course, you have the right to ask questions (I find them very thought provoking)and find out what all of us are saying and thinking about things. I hope you don't think I'm getting on your case.

@Boris: I have learned from you since you had your web page up and gave updates and explainations of what Etna was doing. I'm happy you post to this site for a couple of reasons: (1)you can give a very good perspective as to what is going on and (2) it gave me a way of reconnecting with you. Keep up the good work.

I am posting this here because we are getting quite a few down the pike.

@Shannon: You are very welcome. I don't want you to be afraid of Yellowstone. The more you come to this site, the more you will learn and maybe the volcanoes will become something of real interest to you. I have been intrigued by them since I was at least in the third grade! I used to draw them. Anywya, hang in there keep learning.

@Rick: I don't think the quakes and uplift at Sisters has anything to do with Yellowstone. They are different systems. Yellowstone is a hot spot. Sisters and the whole Cascades are from subduction, I think, if I remember right, of the San Juan De Fucca plate under the Pacific Plate. Also because of the Pacific Plate being up against the North American plate. The North American plate moves westward and the Pacific plat moves roughly NNW. That is what gives us the San Andreas fault in CA. I hope this helps. Any of you volcanologists out there can correct me if I have some of this incorrect.

Diane I don't find any problem with anything you have said to me....we have something in common we both like to pan for gold. Do you ever look for anything besides gold...like beryl, corundum, tantalum and other cool minerals? if you do I will email you some great locations, I would post them here but I don't want to tell everyone. I will tell a nice person like yourself who likes to pan for gold;) I also know where some great complex pegmatites are located. Honestly I would love to see a small eruption....anywhere but Yellowstone:) I also linked to my site so check it out...you might find something there interesting....Please excuse the mess...it's always under construction;)

Dear Randall, certainly the Discovery News guy doesn't think a huge Yellowstone eruption would be anything similar to "cool". But a lava dome eruption would be of extremely limited extent - the more so because Yellowstone is a National Park, differently from our Italian "supervolcano" Campi Flegrei, which has half of Naples in it, and which might well erupt long before Yellowstone.

To be honest, what is going on at Yellowstone is not new, that's the first thing you must come to terms with. It's the totally normal business for a volcano of its kind. The article in Journal of Geophysical Research says simply that there is presumably (not certainly) a quite impressive quantity of semi-molten rock present below Yellowstone, but it doesn't say with a single word that it will erupt soon, just that it is potentially explosive. Duh, what a surprise. But can you imagine how many volcanic systems there are on this planet that are sitting on similar quantities of magma? Just take Etna, the volcano that is just some 10 miles away from my home, which sits atop a huge magma storage area estimated to host some 1600 cubic kilometers of molten rock. But even at a volcano as active and productive as Etna, which furthermore is basaltic (that is, its magma moves much more easily than Yellowstone's), only very small quantities of this magma reach the surface, and much of the remainder is doomed to sit down there and cool and crystallize.

Problem is, some of you folks focus entirely on that one thing, that one volcano, that one scenario, but it would be rather smart to realize that among all the bad stuff waiting to fall upon us this is probably the least likely to happen of all, and those things more likely to happen should rather frighten the hell out of me with our nasty Italian volcanoes here, and - ... well, I am not frightened about the Italian volcanoes, I am very concerned, and I am working with the people here to educate them to be prepared and understand what the risks are. I can assure you that there are lots of people here who show the same type of reasoning that you do, they pick what sounds adequate to confirm their worries and anxieties, but don't look at the rest of the picture.

Personally, I am worried of being run over by a car (not too bad prospects in Sicily) or by debris falling off one of the many relatively modern but badly constructed buildings in Catania - they crumble even without an earthquake occurring - or of dying painfully from cancer. I fear any one of these or something equally evil is about ten million times more likely to happen than a "supervolcano" eruption at Yellowstone or anywhere else.

What is important is, once more, that you understand that the YVO people and our other colleagues worldwide really know their business, they're not there because they've read one scientific publication and watched a few Discovery and National Geographic and BBC supervolcano specials (I don't mean that this applies to you specifically Randall, but it certainly does to a great number of people, including many self-proclaimed experts). We've undergone a long education to get our know-how, and luckily technological evolution in the past few decades has been enormously helpful. And yes, quite a few of us do risk our lives every now and then during our attempts of understanding volcanoes better.
Just believe me, if Yellowstone were up to something big, it would be EXTREMELY evident. We can be certain of this even though no one of us has ever witnessed a "super" eruption, because in the end, the underlying processes are the same that operate in small volcanic events as in large. If we can detect the uprise of 0.005 cubic kilometers of magma weeks in advance at Etna, then I would say with all the monitoring equipment that sits on Yellowstone a much larger quantity of magma moving would hardly be able to go unnoticed.

@Diane, nice to be back in touch after all those years, and your contributions here are quite helpful and accurate - in a particular way because you're actually representing the public, not the expert view of things. It's only that you put them into a perspective of decades of being interested in things volcanic, tectonic, and geologic. I hope that this helps people who come in here and are worried but don't really understand what it's all about, having just seen "2010" or "Supervolcano" or the likes.

I am going to attempt to quell this skirmish with a few thoughts - and as a caveat, I haven't fully the read in question, but skimmed it to get the gist. The idea is that there is more melt at Yellowstone than previously assumed, but ...

1. We don't have a good grasp of what triggers extraction of melt from a crystal mush (sponge) or even what the mechanism is. The melt could percolate through time via density. It could be move upwards with volatiles from degassing magma (called "gas sparging" coined by Olivier Bachmann at UW). It could segregate during a seismic event. Also, will the melt move en masse, will only part of it be moved and in what state (eruptible or not) will it be.

2. Even if Yellowstone has 1,500-2,000 km3 of "melt" in the magmatic system, in most eruptions, the ratio of what gets erupted to what is left behind is something > 1:3, probably closer to 1:10 for continental systems. So, potentially 1,500 km3 of melt might only produce ~150 km3 of erupted material. I mean, it is no walk in the park, but certainly not an extinction level event. As a comparison, the Rotoiti eruption from the Haroharo caldera in New Zealand erupted ~120 km3 only ~60,000 years ago.

3. The geologic community, and the volcanic community, is pretty small. So, I would venture to say that the folks at YVO know the authors of the JGR paper personally, so the findings are likely not new to them. Heck, most papers are the end result of multiple presentations at meetings and workshops where people exchange ideas. It really isn't a shock to anyone in the community once a paper makes it to publication. I mean, I would bet that someone like Dr. Lowenstern at YVO likely reviewed the JGR paper in question before it was published.

4. However, in any case, the point here is in science, we can all have differing opinions and it is through sharing these ideas in a civil fashion, we can determine how to solve these problems. Yellowstone (thanks in part to Supervolcano) stirs up a lot of doomsday emotions in people, which is fair, but similarly, asteroid impact could wipe us out. Or a plague. I'd say we know more about what to expect and how to read the signs of a Yellowstone eruption than many of the apocalyptic scenarios out there (except zombies).

@Boris: Thank you for your comment. Expert, I am not, but I like to study this stuff and I did order one of the books Erik suggested. I have only had one geology course and it was back in the '70s! We had two teachers and one of them had a book that was all the seizmographs from all over the world of the 1906 SF earthquake. It was an original copy, too. Cool book.

The main reason we lost touch is I forgot to send you my new email addy before I changed it and I figured your spam filter might reject it. It is good to be back in touch!

@Randall: I am an avid rockhound and belong to a club called the Motherlode Goldhounds. We have fun. I am limited in where I can go and so is my DH. He was a miner and knows a lot about where to find stuff. I will write more later. I have a tree man here. Catch you later.

i had to laugh at the video...........
With the guy going thu Etna's conduits, lighting his face
for the camera and not the surroundings in particular/
he could have been showing off my basement without the
lights on. Ah, well.
i'm facinated with living on the Nothern Ring of Fire.
It's something i'd always heard about and moving here
immediately after the '64 earthquake i feel in love with
all the volcanoes. Altho they do pose some disruptive
problems it's exciting to live near them. Nothing like being on the edge of destruction. It makes the mudane in Your life acceptable....... like i'm trying to catch a
very smart mouse in my kitchen and when down, the comforting thought of "Well at least the volcano hasn't buried us in ash this morning." always puts things in prespective. ;)
Masks hang at our door and are in our cars and i even carry a few in my purse....... talk about being prepared.
i love whipping one out....... TADAAAA!
Thanks for Your very fun site and all the informative posters.
One of my favorites and a daily musts!
Best!motsfo off to check the Africans.......

I understand what you are saying Erik and I do respect you because you are not condescending. I will have to say this though to Boris that I have never watched 2010, I don't believe in any of that stuff....Nostradamus is bull...Here is what I do believe....I believe 32% melt saturated with 8% water plus CO2 by volume verses 10% melt is quite a difference. I never said the paper said anything about how it's about to blow right now....The paper said the earlier measurements were way off...The paper said that there is a considerable difference in what was thought to be melt in earlier papers and what's on the on the YVO site. This means that there is a much bigger potential for an eruption. What percentage of melt do you need to reach before an eruption can theoretically occur? I do respect you Boris and I wish you would respect what I am saying and I wish you would just answer my questions without all of the reassuring analogies.

From my perspective, as a long ago materials engineer (think "phase change") this discussion just reminds me of how cool it is to be at Yellowstone and think of all these complicated processes going on just underfoot. The risk considerations that Dr. Benke points out are right-on. You are much more likely to get injured on the way to Yellowstone (in the rental car from Bozeman for example) than by any geologic feature in the park itself. Bee stings are probably the high point on the risk-of-injury-due-to-nature curve within the park boundries, provided you pay attention to the "don't try to pet the bison" warning signs.

Maybe the most important task that society expects of geologists is the development of science-based policies related to urban development in hazard areas. Port-au-Prince is just one of many densely populated areas sitting astride earthquake zones with inadequake or even non-existant building codes. Karachi, Katmandu, Instanbul are all poised for disastors of similar magnitude. Volcanoes, by providing elevations, water and fertile soils, stimulate development in hazardous areas on their slopes and flood plains. Societies and governments need to understand and mitigate these risks.

As highly interested observers, amatuer volcanologists, dedicated rock hounds and the like, the rest of us can do our part by insisting that our schools teach these subjects in the best way possible and that our politicians fund the programs that help advance the science and implement make-sense policies. This blog is a great forum for us to exchange our ideas in this regard. Thank you Eric, Boris and all the rest.

stepping off the soap box, for now,

doug mcl.

@Randall, I'm not getting the point about the "reassuring analogies". I do respect what you are saying (and that's why I'm spending a bit of my time here responding), but I do not think that anybody should worry about Yellowstone in particular, and not worry about much more dangerous things. That's the first point. Second, if you believe that you have cancer and go to a doctor and he says no you don't, and maybe you go to see a whole bunch of doctors and they all say, no you don't have cancer, will you insist any longer or shouldn't you be rather happy that very obviously you don't have cancer?
I hope you understand that I am a very normal human being like you and I do have my own anxieties (I mentioned a few in the message before), which are based on real probabilities, unfortunately. But when it comes to volcanology I think I have my things together. So please do accept when I try to reassure you: there is not very much to worry about Yellowstone in this moment, not more than in 1985 when there was surely as much magma below the volcano as there is now, but nobody talked about it. And not more than a great number of other volcanoes, which threaten half a billion people worldwide. It is the analogies as you call it, or the comparisons, which make us understand the real significance of Yellowstone. It should make you understand that there is really nothing extremely frightening in the data about Yellowstone you refer to, fascinating as they are. As Erik Klemetti said before, things need to be put into perspective. Thinking about Yellowstone is worth nothing if you don't think about other volcanoes, other hazards, other threats to our lives.

@Randall. I don't mean to be rude, and perhaps it is besides the point, but judging by your website, your preoccupation with disaster sits just this side of the people over at fearmongering sites like democratic underground, 2012forum, and what have you. At least you are coming to a sane and informed message board to ask questions, but the knowledgeable amateurs and professionals here are giving you sage responses. There is no evidence that Yellowstone is any more likely to super-erupt than ever before. Ground deformation has slowed. The current swarm has slowed and deepened. Lots of regular, normal heat and gas discharge indicate that magmatic cooling and outgassing are occurring. The swarm is still smaller than 1985's, and who knows how many larger swarms occurred in the tens of thousands of inhabited years since the last event 70,000 years ago, before people began recording measurements.

By Peter Simmons (not verified) on 05 Feb 2010 #permalink

Thank you for your response Boris and I do appreciate you trying to answer some of my questions. I would still like to know, if you happen to know just off hand.... If the magma chamber is 32% melt instead of the 10% reported in earlier papers and on the YVO site...then please let me and everyone else here know just what is the theoretical level of melt that has to be reached before an eruption can occur?

Thank you for your time and consideration of my questions. Thank you again Erik for providing us an opportunity to ask someone like Boris questions, to express our opinions as well as the concerns that I and others may have.

@ Mots: I loved your post. I figured it was you before I even saw who posted. Love your sense of humor.

Remember all the hype about Y2K? Some of the posts seem to be echoing that a bit in the sense of being scared. Life can be capricious and there are the normal things we live with that can wreck havic on us. Just about a week ago up in town, a very large oak tree with a cedar that had grown up in the branches fell. It did some minor damage to the dentist's office, which is an historic building because it was the judge's house from way back. The tree took out the old courthouse which the dentist used as a community program called Elijah's Jar which helped some of the less fortunate in town. The tree also damaged a shed that was on another lot.

You see, anything can happen and where I live, trees come down, the electricity goes out, in spite of PG&E replacing the old substation and trying to avoid this problem, and a wild fire is more likely to happen than an eruption at Yellowstone. In fact, since I have lived here, there has been a fire just about every year. Most are not major, but we have had some doozies.

The point is, there is no such thing as security or safety. There is only the illusion of security and that is what gives us a sense of assurance and peace about where we live and how we live. To illustrate, I used to be terrified of spiders; even the little corner spiders that are in the house sometimes. Then I did some studying of spiders and I have pretty much gotten over my fear of them. We have a lot of black widows here, too!

Anyway, I hope we can get over the fear and uncertainty,
focus on how the forces of the earth work, and enjoy the learning process. One of the best ways is having a sense of humor. Concern is one thing. Worry, now that is something else again. To use the volcanic color code, we can maintain a level of yellow, but we cannot maintain a level of orange or red because it does damage to our bodies. I see Yellow as awareness and concern, orange as scared and worried, and red as panic.

I hope I have made some sense. There is always something we can find that helps us feel safe, aware, and ok.

Now all I have to do is wait for good weather and go to the river to find some of that yellow stuff. Haven't gotten skunked where I go yet! :-)

Randall -To answer you question as directly as possible (you're not going to like it): there is no known "magic number" for melt and eruptions. It isn't as simple as when the system hits x% melt it erupts. So, no, just because we know it has more melt doesn't mean it is any closer (or further) from eruption.

Peter, thanks and in no way are you being rude. I am happy you went to my website. As I said before I don't believe in any sort of 2012 stuff, you won't find that there, and I don't believe God's wrath is upon us....I am sure he has better things to do....so you won't find any of that there either. I am asking and trying to get answers to a few questions, really isn't that what this site is all about. Yes I came here instead of other sites I could have gone to for some real answers. Also when you look at my site please understand that I just list the potential disasters. I don't predict them and I try to do it all with an element of dark humor....so please don't get the wrong idea. I found a paper that had some disturbing information in it so I came here to find some answers.

Erik, You are wrong about one thing...I did like your answer;) I like getting direct answers. I can assure you that I will be very happy to never see an eruption at Yellowstone....I do have a few more questions and if it is OK with you I will be back to ask them at a later time. Thanks again!

1) This is the NICEST debate I've ever had the pleasure of being involved in.

2) When I was 4 yrs old a brown bear tore open the side of our tent in Yellowstone and "rolled me around a little" in my sleeping bag. I didnt smell tasty enough so it left, and tore out Coleman Cooler in half and ate that instead. I slept thru it all.

3) We have brown recluse spiders in the basement ALL the time. Lived here 12 yrs and havent been killed yet.

4) House is in Kansas - Tornados - 52 yrs old - still alive.

5) Odds of getting squished crossing the street, higher than death by Yellowstone - but I have to cross the street to get to Yellowstone, so thats twice as bad. XX Im afraid of EVERYTHING, heck Im an engineer, but I still took flying lessons. Its all relative.

I took this except from:
Monitoring super-volcanoes: geophysical and geochemical signals at Yellowstone and other large caldera systems
Jacob B Lowenstern1,*, Robert B Smith2 and David P Hill1
+ Author Affiliations

1US Geological Survey, Volcano Hazards Team, MS 910 345 Middlefield Road, Menlo Park, CA 94025, USA
2Department of Geology and Geophysics, University of Utah 135 South, 1460 East, Room 702, Salt Lake City, UT 84112, USA
*Author for correspondence (jlwnstrn@usgs.gov)

"Overall, geophysical and geochemical evidence points strongly towards the presence of a large thermal anomaly in the shallow- to mid-crust. Given the size of the caldera and the implied depths, it is reasonable to infer that at least 15â000âkm3 of crystal-melt mush are located beneath the Yellowstone caldera, at depths from ca 8 to 18âkm. If melt fractions are 0.1â0.15, then sufficient melt exists to form the mass for a super-eruptionâif it can be extracted and accumulated into an eruptible volume. Most geophysical images have insufficient resolution to define volumes less than ca 10âkm on a side. It is fully plausible that volumes with high melt fractions (more than 0.6) exist within dikes and sills within the greater magma chamber, and could erupt as moderate-volume (less than 100âkm3) lavas or pyroclastic flows. Current evidence suggests, however, that the gravity and seismic anomalies are not sufficiently large to allow for a larger, highly molten (and thereby eruptible) volume of magma beneath Yellowstone at this time."
http://rsta.royalsocietypublishing.org/content/364/1845/2055.full

Sorry Erik, please don't be angry with me but it seems like someone already has given us some hard numbers on what percentage of melt we would have to reach before the magma becomes and I quote "(and thereby eruptible)".

I think the key in that statement about 10-15% is that it is eruptible if it can be extracted and accumulated into an eruptible volume - which is a big if. Of course if you have a mush with that much melt, if you concentrate it, it could erupt. However, I don't think that statement is meant to be interpreted as any magmatic system with 10-15% must erupt. Instead, they are just saying that it could take as little as that - but that is a lower bound, not a threshhold. At least that is my take on it.

Oh I didn't take it as any magmatic system with 10%-15% must erupt either...I think the number is higher than that. My point is that they do have an idea of how much melt that would have to be reached before a possible eruption. Also:

"Current evidence suggests, however, that the gravity and seismic anomalies are not sufficiently large to allow for a larger, highly molten (and thereby eruptible) volume of magma beneath Yellowstone at this time."

The paper I posted sort of conflicts with thier conclusion.

@Randall

I have browsed through your website and understand you better.
I see you as a sick individual that preys on the fears of others. I believe that you are using this highly respected forum to raise your stature, so others see you as an individual that is also worthy, and one to respect. You disgust me. Your website says it all.

The paper I posted sort of conflicts with thier conclusion.

And that is what we call "science". We debate the theories we have about how this system works, we evaluate new evidence and when it is appropriate, we change what we think based on that new evidence. If you talked to 10 different people who study systems like this about just such a question, you'd get 10 different answers - and no single paper will change that. Certainly the study is interesting, but by no means does it really change anything we know about the system - at least not without rigorous corroborating evidence. There might be some estimates about melt and eruption or the amount of melt currently present under Yellowstone, but by no means is there an agreed-upon value. That is why we continue to study the system!

And with that, I withdraw from this debate.

Those who worry about Yellowstone need to readjust their relative risk perspective.

Supervolcanoes eruptions are rare, for good reason: they are exceptionally massive, high-energy events. The snail-like development of precursor conditions and eruption catlytic factors necessary for a supervolcano VEI 8 event, - it simply ain't gonna happen anytime soon.

We are past the event time frame of sufficient internal (deep mantle) and external (solar cycles, intergalactic forces) necessary for supervolcanic eruptions These occurred last during major large igneous province formation - many, many millions of years ago.

http://en.wikipedia.org/wiki/Supervolcano

The Columbia Flood basalts that helped feed the Yellowstone hotspot have done come and gone.

The VEI 7 events are worth a worried thought or two, being closer in event phase time frame to the present. Two occurred in the past 2,000 years and the last within the past 200 years. The majority of known VEI 7 eruptions, however, are hundreds of thousands or millions of years in the past.

The most recent VEI 7 eruption, in 1815 was climatically destructive (effecting global climate for a decade or more) because we had 1 or more temporally clustered major eruptions from other, unnamed volcanoes that left traces in ice cores at both poles.

The Laacher See eruption in Germany, about 13 KYA, was one of the really big climate re-arrangers, along with eruptions not listed on the wiki-page at about 17KYA (the largest single SO2 signal in ice cores data) and another biggie approximately 8,000 years ago.

It's the timing of clustered eruption events that one must be attentive to - cumulative volume of acidic gases and type ash emitted over a period of a few years.

Supervolcano eruptions are far, far down of the list of worrying topics to ponder at 3am.

I lied, one more thing: the Laacher See in Germany is super cool. I visited the area a few years back and you can still find CO2 seeps in the lake that fills the caldera. The caldera isn't that far from Koln in the Rhine Graben. Maybe I need to write something up for the blog on the Laacher See ...

Thanks Erik for your time and answers. I am sorry if I made some people angry....I have always thought you were not asking the right questions or getting the right answers if everyone agreed with you or you didn't make at least someone mad. I will let Gordys comments go except to say that I don't prey on anyone's fears. I don't make any money from any advertising on my site, that site is just something I made for myself as much as for anyone else. I don't tell anyone what to do on there or even what might be about to happen. I list things and give links to the information on my site. If you find some of it factually wrong please bring it to my attention and I will change it. About the only thing I really do there is throw in a little gallows humor and a few relevant quotes. Trust me, if I wasn't actually concerned about a few things and I didn't think I had a reason to question them...then I sure wouldn't put myself in the lions den and open myself up to ridicule or comments like yours. My goal was to raise questions and get answers and make a few people think about some things and I think I did that. Once again Erik thanks for your site and allowing me to question a few things. I always did think Laacher See was an interseting volcano....I would love to know more about it.

The idea to have a bit on Laacher See here is not a bad one, because it's quite an interesting one, in a place where most people wouldn't imagine a major volcano (or a potentially active volcanic area), and source of a massive (though not "super") eruption about 13,000 years ago. There was a bit of a discussion about it already in September 2009 on this blog:
http://scienceblogs.com/eruptions/2009/09/monday_musings_more_australia…
I passed much of my infancy and adolescence between Frankfurt and Cologne (Köln), not far from Laacher See and thus it was one of the first volcano I've ever visited in my life. It's a hauntingly beautiful place, all the Eifel volcanic field it belongs to is a sweet, lush green, hilly landscape with little historical towns and villages, lakes (many of them volcanic - they're called maars, and the term comes from there).
The Eifel volcanic field has recently been the subject of a German TV fiction last fall, depicting - very much "Supervolcano"-style - a Laacher-See-type eruption occurring today. While you can debate the quality of the acting and the storyboard as a whole, the movie came accompanied by a short documentary, which brought up a few sizzling questions: is it possible that there will be another volcanic eruption in Germany one day? (YES), and are the people, the authorities, and Civil Defence prepared? (NO).
However, as at Yellowstone and any other volcano, odds are that the next eruption will be a small to modest-sized cinder cone-building event, rather than a Laacher See size cataclysm.

Explosion at Soufriere volcano in Montserrat
Friday, 05 February 2010 14:54

Explosion sends Pyroclastic Flows to the sea
âAt 1:49 pm 5th Feb 2010 a vulcanian explosion occurred from Soufriere Hills volcano.

At 1:49 pm 5th Feb 2010 a vulcanian explosion occurred from Soufriere Hills volcano.

The event lasted 7 mins and sent pyroclastic flows mainly to the west of the volcano with pyroclastic flows rapidly reaching Plymouth and spreading across the sea for around 500 m. Short pyroclastic flows, up to 2 km runout, also travelled down Tyers Ghaut to the northwest and Whites Ghaut to the northeast. A plume rose rapidly to 21,000 ft (confirmed by pilot reports). There was no lapilli or ash fallout in inhabited regions due to an easterly wind direction. Precursory activity included only ash venting, although the event coincided with a cycle of increased activity.'
http://www.montserratvolcanoobservatory.info/index.php?option=com_conte…

By Randall Nix (not verified) on 05 Feb 2010 #permalink

@Sightseer: I wouldn't worry about the quakes in Yellowstone. Their magnitudes are not high enough to affect a motorcycle. Even a 3.8 could be navigated. The worst you would see would be like a dirt road. And I seriously doubt you will encounter anything like that.

Something happened to me that I though was rather humorous when years later I figured out what was going on. It was during the Loma Prieta quake. I had just left UPS and headed for Sac on I80 when the road felt kind of rough and I could see a ripple in the road that made it look like a washboard. Near where I live, they were working on the road and I was thinking they needed to fix this part of the road, too. Well, I got to where I was going and they announced on the radio about the quake. It made the water slosh in my parents' pool! I didn't think anything about it after that until years later when I decided to see if that part of I80 did need fixing. It was rather smooth with no washboard look to it at all. That is when it dawned on me I was seeing the ground waves from that quake and I was driving perpendicular to them! As strong as they were, I had no trouble keeping my car under control. The road just felt and looked bumpy.

I do know it is a little different riding a motorcycle, but be assured, Sightseer, that it takes a rather strong quake to make the road hard to drive on. Just keep watch and go and enjoy Yellowstone. I think you will have a great time.

The webcam image of Soufriere volcano from MVO has shown a much larger eruption along with smaller eruptions earlier today, at approx. 21.51 local time Feb 6th. The dust cloud bellowed into the camera forfield. Amazing images!

Major plinian ejection, Montserrat, 22:29. Blocked out the camera image at 22:31-33. Spectacular images just before blackout.

FWIW, keep your eye on the Kurils, probably Sarychev Peak for a major uptick in activity.

Another place to see some fantastic pictures of Montserrat by Marco Fulle is to go to Stromboli Online.

www.swisseduc.ch/stromboli/

The area to check out is on the right near the top of the page. You will see a link to Montserrat. There are pics from this year and 2002. Marco does a great job of catching some cool shots of wild pyroclastic flows. Awesome and scary! Enjoy.

Did I read 'Laacher See' in posts 27, 28 and 29 ;-) ? I just love the Eifel volcanic fields. My mother is a geography teacher, and her fascination for geography and especially geology appeared to be contagious (I was still only like five years old at that time). Especially volcanism has always interested me a lot. That's why we went to the Eifel two years in a row for the holidays when I was a kid, the first time when I was 8 years old. I live in the South of the Netherlands, so it's only about two to three hours of driving. Nowadays I go there a lot, every few months or even weeks if possible, just to enjoy being there among the volcanoes and to collect rocks and minerals. Although I think the East Eifel is beautiful and is more interesting from a geological point of view, the West Eifel has an even more beautiful landscape.

I'm going to Laacher See again on February 18. I'll also visit the Rieden caldera ('Hatzenfeld' quarry) and the Dachsbusch scoria cone (which is next to the Wehr caldera).

By Gijs de Reijke (not verified) on 06 Feb 2010 #permalink

@Gijs, rocks and minerals did you say? I'll be right there! Seriously, I wish I could afford to go there to see the area. Must be beautiful from the way everybody talks about it. For now, I have to settle for Long Valley which is a looooong drive from here. Oh well...

I was just wondering if some one could help give me some insight. Why do you think there was an earthquake swarm right around the same exact time in 2008 and 2009? Didn't they both start occurring right around Dec 26th? Please correct me if I'm wrong. Also, thanks for taking the time to read this and I appreciate your response.

Maybe Erik will go to the Eifel again some day. Perhaps you can join him ;-) ?

From what I've seen of the landscapes of the Long Valley area, the Eifel is not nearly as spectacular. The highest point ('Hohe Acht') is 747 meters asl, the average hight in the West Eifel is around 450 meters asl and in the East Eifel around 350 meters asl. A large part of the landscape is forested, in the West Eifel more than in the East Eifel. Not all of the volcanoes are easy to spot, but the Ernstberg (sometimes called 'Erresberg') for example is one of the largest scoria cones, and the highest scoria cone of the Quaternary volcanoes.

http://upload.wikimedia.org/wikipedia/de/7/79/Erresberg.jpg

The area is very interesting (especially to us Europeans), but not really different from most other volcanic fields around the world.

I've posted the idea before... But the Eifel and Laacher See specifically (for example) are topics that keep popping up, as is Yellowstone. Maybe an internet forum moderated by Erik and/or some of the regular visitors of this forum might be nice?

Anyway: I think a Laacher See special for the blog is a good idea ^_^ .

By Gijs de Reijke (not verified) on 07 Feb 2010 #permalink

@Bas: the 2008-2009 Yellowstone earthquake swarm started 26 December, the latest one on 17 January 2010. Thus the starting dates are similar but not identical, and in any case they're coincidence: dates are our way to subdivide time into units. Yellowstone's movements are determined by slow pressure and temperature changes at great depth, and by the overall game of plate tectonics and magma generation within the Earth, which are extremely complex and often random processes. So there is a vanishingly small possibility that the two earthquake swarms occurring during the winter season has any meaning.

#Gijs, although Etna and the other Italian volcanoes are supremely spectacular and fascinating, I do miss the Eifel sometimes. The sweet, sinous, hilly, green landscape with its lakes, volcanic and not, is unlike anything you find here. One day I will have to get back there, surely to show the country of my origin to my little daughter!

There seems to have been quite a lot of increased activity at the Soufrière Hills volcano (Montserrat) this weekend. I don't think it should be called a Plinian eruption as supposed by Passerby - that would have decapitated the lava dome but today's webcam images show it's still very much there. But certainly the volcano is very active, and maybe I'd really go there first right now and then to the Eifel volcanic field in Germany ...

The Laacher See eruption coincided with the last large eruption volley from the East Eifel Volcanic Complex, and temporally-clustered high latitude large eruptions elsewhere, over a period of approximately a thousand years.

Yes, indeed, it would be a GOOD THING to discuss the Younger Dryas eruptions in western-central Europe. The Eifel Hotspot has very interesting and complex geology.

And it is pertinent to later discussion.

@ Boris: I was meaning to ask you if you don't miss it :) . I think the Eifel is fascinating to me because it's so close to home. That's why the kids I teach geography always show extra interest when I mention the Eifel volcanism or the seismicity of the graben systems around it when I talk about geology. And I keep going back to it. Events like the eruption of Pinatubo and Chaitén are 'nice', but the Eifel still has something extra. The formation of a new small scoria cone there would probably interest me more than a 1.000+ cubic kilometers eruption at *cough*Yellowstone*cough* ;-) . I think it would actually be good for the Eifel economy if an eruption happened there. The area would attract even more tourists than nowadays.

Apart from the geology of the Eifel: I find the landscapes beautiful as well. I could find myself living in the Liesertal or near the Kleine Kyll in the future. Or maybe in that villa inside the Bausenberg crater ^_^ .

If you ever plan to go to the Eifel again, please let me know if you don't mind ;-) . I'm always in for visiting the area, even more with other volcano enthousiasts (especially if someone happens to be a volcanologist ;-) ).

@ Passerby: the Eifel volcanism is most likely not the result of a 'classic' hot spot. But there's definately a (relatively shallow) plume shaped anomaly beneath the area.

And The Laacher See eruption was actually the only EEVF eruption that is younger than the 115.000 year old Dümpelmaar eruption. The WEVF is the only place in the Eifel that produced eruptions between those two events and after the Laacher See erupion.

If some large eruptions around the time of the Laacher See eruption are indeed more clustered than usual (which I kind of doubt, because eruptions sized like the one at Laacher See happen all over the world more than once every century, and I don't know if there's any data available on if more large eruptions happened then than before and after that period), maybe they're related to isostatic compensation after the disappearance of large ice sheets. But they would also have to be clustered not just in time, but also in space (relatively close to areas that were covered by large ice sheets during the Weichselian glaciation) and I don't know if that's the case.

By Gijs de Reijke (not verified) on 07 Feb 2010 #permalink

nuts........ i spent 2 years in Germany(Air Force Brat)
and i never knew there was a volcanic field........
Got drug to every historical spot(Thanks, Mom for improving
my education and interest in the world) but the geostuff
got ignored. i would have loved to see the volcanoes of Italy and i wasn't very far from the German site.
Well i'm within 50 miles of Redoubt so here towards the end of my life i get to keep company with volcanoes.
And even sweep the ash from my floor.
Thank Heaven for informative sites and educated people to
'splain' stuff.
Best!motsfo

@Mots: Isn't that the case with parents?! When I was three (don't ask me how I remember, I just do LOL) we went up to Canada at the time the qween was being coronated and one of the things my mom just had to do was go to Buchardt Gardens. I rememeber the trees and bushes and that is about it. At the time, I could not see what the big deal was.

Later, Mom did not tell me that a place in town called Rock Garden was closing down and giving away beautiful rocks! One gal who got there brought a two foot long quartz crystal to school! Rats!!!! I was pretty upset with Mom to say the least.

Under the post on Tungurahua, is a post about it still being active this morning. There have been several explosions.

1) I agree, Erik should consider a Forum format for these long single topic discussions, especially since everyone is so well behaved.

2) I drove over the La Garita Caldera a dozen times and only just within the last 2 yrs found out there was a volcano there. I was raised by the media believing all volcanos are on the West Coast.

3) I bet the Eiffel is gorgeous, but probably too eroded and overgrown to seem "volcanic". Thats not a bad thing.
The Black Hills are very scenic too, but YS has the geysers. Too awesome.

Well, we have had some "'ahem' healthy discussions"here.:-) I suppose a forum would be ok as long as we stay cordial. I am just thinking of some who might stumble on the site and go a bit overboard. Personally, I like the way it is, but change can be a good thing, too. Then we could have a couple of places to exchange ideas.

Erik, what do you think?

@ Fitz: Not to have noticed the volcanic origin of the deposits of the world's largest explosive eruption known XD ;-) . More recent studies show that it's the only eruption known to have produced a VEI 9 with around 11.000 km3 of ejecta. I wish to go there once. Some parts of the rim of the caldera (especially the Northern part) are still very visible, much more than in Yellowstone and other great calderas of the Snake River Plain. And ofcourse the Wheeler Geologic Area is beautiful ^_^ .

The Eifel is too young to be very eroded, and the climate is too mild to cause a lot of erosion. The scoria cones have always been small though, because of the limited size of the (monogenetic) eruptions. But still most of the volcanic features are visible enough to recognize, if you know what to look for. The volcanic fields are situated on top of a plateau, so most of the land relief is formed by volcanoes, exept for some (small) valleys that have formed due to erosion of the Devonian slate that forms most of the plateau.

@ Diane (and the rest): there are several ways to moderate a forum. One is, for example, by technical limitations. Certain subforums could be accessible only for 'members'. The more 'serious' or 'personal' topics could be placed there, so the public wouldn't know too soon we'd be discussing an impending eruption of a big caldera, for one thing ;-) . Or maybe we can exchange more personal info there. For example: we could introduce ourselves to each other.

The rest of the forum could be visible to the general public. Topics concerning what we discuss here at the blog could be put there.

A forum that works kind of similar is www.strahlen.org (which might be something for you Diane, because it's an international forum for mineral collectors and rockhounds with the motto 'there are no strangers here, only friends you haven't met yet')

Just an idea ;-) . I'm not trying to cause mutiny here ^_^ . It's Erik's blog, and it's already great as it is!

By Gijs de Reijke (not verified) on 07 Feb 2010 #permalink

@Gijs: I didn't think of any kind of mutiny ;-D. I think you already know that. I had no idea how to moderate a forum so I was just raising an issue that a friend of mine had a long time ago with a message board. Had to shut it down.

What did you mean by the largest known explosive eruption? A VEI 9?! Which one was that?!! I didn't catch that in your post. Just tells me I need to study more about this stuff which I will be doing as soon as I get that book! It will be a start even if I have had a course in geology. A lot more is known now. Of course, I had no idea there had been a large volcano in Germany.

Learning all the time. :-D

BTW, Gijs, thanks for that forum site. I have one more question for you: are you a geologist/volcanologist?

@Gijs: A forum would be a great idea.
I live in Germany, in the Tanuns mountains. There we have only a little unknown volcano "Altkönig". But I know also the Volcano Eifel, which is natural more fascinating. Until now I visited it only two times, but I know I will go back soon, because it is really a beautiful place. I love for example the "Nettetal" in the East Eifel... And in which country is it possible to stay for holidays in a hotel inside a volcano crater, like in the Meerfelder Maar?
Today there was a little earthquake in the volcano Eifel near Daun. It was very little, and not worth mentioning, but because of the Eifel-Volcano catastrophe film last year on RTL, more people were frighten there today than they would be in the past.
I think the film was nearly so good four the touristivc n the Eifel than a real volcanic eruption. -_^

@Diane: We have a lot of volcanos in Germany:
Eifel, Westerwald, Siebengebirge, Hessische Senke, Rhön, Erzgebirge, Westerwald, Siebengebirge, Schwäbische Alb, Vogelsberg, Kaiserstuhl and the little Altkönig in the Taunus. But they all are sleeping... :-)

@Randall: Can I ask you what the purpose of your webside is? Sorry but I don't understand it why you are "collecting disasters and things which could frighten people" there.

The Younger Dryas lasted too long for it to have been caused by Laacher See alone...Boris do you know of any other super eruptions around that time that would have lasted 1600 years?

@ Diane: I'm a geography student at the moment, but I've been fascinated by geology for almost as long as I can remember. It runs in the family, with my mother being a geography teacher and her father was one as well. People learn to think as a geographer before they can walk ;-) .

@ Diane & Randall: The Volcanic Explosivity Index has no limit, like the Moment Magnitude Scale and the Richter Scale. Because the limit of a VEI 8 is 10.000 km3, it means that the La Garita caldera forming eruption 27,8 million years ago was a VEI 9 with around 11.000 km3. However, the number of 11.000 km3 is new. Old estimates give a number of 5.000 km3, which would have made it a VEI 8. I don't know if the more recent results are commonly accepted in the geologic world as being more accurate.

@ Diana: for as far as I can see the Altkönig is made of Taunusquarzite, which is a metamorphic rock. I can't find any sources on the mountain being an old volcano I'm afraid :\ .

The quake near Daun (to be more precise: immediately Southwest of the village of Boxberg) was a 2.8 at a depth of about 10 km. For the West Eifel that's something :P . The area has been very quiet for as long as records show., and most wuakes that occur over there are like this one or even lighter.

It shows how much of an effect the movie had XD . I'd personally be more worried about the East Eifel, although nothing really shows that anything like an eruption is about to happen there. Like in Yellowstone, only the Eifel is showing even a lot less signs that can be related to volcanism.

Oh, and in Germany other volcanic areas (of Tertiary age) are the Heldburger Gangschar, the Hegau and the Kaiserstuhl. Especially the Kaiserstuhl is absolutely fascinating, with it's carbonatite lavas. The phonolitic domes of the Hegau have some unique orange natrolite ^_^ .

Meerfelder Maar is beautiful. I always go to the Leyendecker quarry immediately West of the crater to look for (large) peridotite bombs. The largest one I found so far was 50 cm across ^_^ .

The RTL-movie 'Vulkan' was cr@p btw 0_o' . I want my 3 hours and the money for the dvd I bought back -_-' .

@ Randall: the Laacher See eruption produced around 6.3 km3 of ejecta. Not anywhere near the minimum amount of 1.000 km3 needed for a 'super eruption'. And I agree with the volcanologists: the term 'super eruption' is not the right one to use I think. 'Large caldera forming eruption' would fit better ;-) .

@ Diane: moderating messageboards can indeed be difficult sometimes, but everyone here behaves so well... ^_^

At the Strahlen.org forum everyone has to introduce themselves. The admins can check that way if someone's genuinely interested. For the diehards, like all the regular commentators here ^_^ .

By Gijs de Reijke (not verified) on 07 Feb 2010 #permalink

@Randall: maybe there was not much volcanism necessary to keep the climate cold during the Younger Dryas - global climatic variations are hilariously complex processes that depend on a broad range of different parameters, of which large volcanic eruptions are only one. There are many other things such as reflection of solar radiation from ice- or snow-covered surfaces, changes in oceanic current directions, and so on. It seems that climate change can be induced without dramatic triggers such as volcanism, and there is still much mystery to be resolved. Actually, the effect of massive (and necessarily, sulfur dioxide-rich) eruptions on global climate is, as you noted, rather short-lived - a couple of years to maybe decades at best. That's were the other factors have to come in.

It's because all these processes are so complex and still poorly understood that I think we should be very careful about all our actions that could have an impact on global climate and on the environment overall. Theres's those folks who talk of the "Global Warming Swindle", and I do not agree with them - we simply should not dare acting in a manner to produce effects that would fall back onto us first.

@Gijs, thanks for all your info about Laacher See (as we all know, it's become important enough to have its own feature on the Eruptions blog now). There's one thing about that "Vulkan" movie on RTL (which is indeed crappy - I did actually download it, and then laughed my butts off watching it), which is: it has heightened the awareness of the German public that there are potentially active volcanoes in that country, which very few people knew so far. The "documentary" that came with it - let's forget the sensationalistic tone it has - did point to an important fact: there is no systematic monitoring of the Eifel volcanic area, which would be about as justified as monitoring Yellowstone. Although I don't count on seeing an eruption in either Eifel and Yellowstone during my lifetime, systematic monitoring of these systems is necessary because, after all, you never know and it's always "better safe than sorry".

@ Randall: if I may quote from the Wiki-article: "The scale is open-ended with the largest volcanoes in history given magnitude 8." It's the third sentence of the text ;-) . So IF the number of 11.000 is correct, it was a VEI 9.

@ Boris: I totally agree on that. The Germans do know now that there's a potential risk of future eruptions in the Eifel, although more accurate monitoring is needed. Geologists and volcanologists like Ulrich C. Schreiber (I like his book far better than the movie, although I don't really like the part where tholeitic lava blocks off the Rhine) and Hans-Ulrich Schmincke said the same thing in the documentary that was broadcasted after the RTL aired 'Vulkan'.

Btw: to the public just outside Germany (the Netherlands, France, Belgium...) the hazards the Eifel might pose are unknown. Only those who are professionally interested or interested out of a hobby (or both, as in my case) know that there are volcanoes in Germany. A small part of that group knows the Eifel is dormant, and not extinct.

More seismometers, more materials to measure gas emissions, maybe even some tiltmeters... 'better safe than sorry' indeed :) .

By Gijs de Reijke (not verified) on 08 Feb 2010 #permalink

Gijs de Reijke, Where do you see that? It goes from 1-8, there is no limit on how big it can be but it will still be a 1-8 at least on the VEI scale. After that you have a Vern Shot but that didn't happen at LaGarita. Boris please explain to Gijs de Reijke about the VEI. Also I agree with you about the Younger Dryas not being caused by volcanism, it could have been a trigger but not the cause of 1500-1600 years....not unless it was a flood basalt such as the Siberian Traps or the Deccan Traps.

The VEI is logarithmic. It means that every level is ten times stronger than the level before, just as in the Richter scale. The limit of a VEI 8 should be 9.999 km3, but until recently no eruption that ever occurred was thought to exceed that limit. That is why no number larger than VEI 8 has ever been assigned to any eruption. It sometimes, like in this instance, causes the misinterpretation that the VEI is by definition something between 0 (non-explosive) and 8. However, like the English Wikipedia article describes, it's an open-ended scale. If the more recent numbers on the La Garita eruption are correct, that is the only eruption known so far that was a VEI 9.

In the end, it doesn't really matter what VEI-number we give these events. They happen, they're sometimes friggin' huge, and the scale is only there to help us understand (just a little bit) of how big these things can get. Personally, I don't care if the scale would be limited to 8 or not. That's not the point of the entire thing ;-) .

By Gijs de Reijke (not verified) on 08 Feb 2010 #permalink

I know they were huge. LaGarita was big but even more than that it was very long lived. I have spent quite a lot of time around there. Outside of the town of LaGarita you can find some really nice Thunder Eggs lined with amethyst. The geology of the neighboring San Louis Valley is also quite interesting.

@Randall: although Gijs has already given a response to your comment on the VEI scale, let me try to clarify this a bit further.
The VEI, like the famous Richter scale, is open upwards, that is, it can theoretically have any value from zero to ten or twenty or hundred or thousand, only that in real life, we won't get any earthquakes much stronger than 9.5 on the Richter scale, and hardly any eruptions with a VEI greater than 8. But since that gigantic Fish Canyon eruption of La Garita caldera may have produced more than 11,000 cubic kilometers of magma, it must be necessarily given a VEI of 9. In that sense, the Wikipedia explanation is not correct, saying the VEI goes only from 0 to 8 - so it actually needs to be corrected.

Thanks anyway for considering me an authority in the field :-) but count on it, Gijs is no less an expert than Erik and me! And I am really glad that you and other interested people do get the informtion they look for in this forum.

Boris I am going to try this one more time with no links since it said my comments were being held by the owner of the blog for review. If what you say is true then some better tell the USGS (and others) that they are wrong.

By Randall Nix (not verified) on 08 Feb 2010 #permalink

@ Boris: Thanks for the compliments ^_^ .

I find this blog a very good portal for getting the scientific world in touch with 'the public', so I'm always very interested in what others here say, and where ever I can I like to contribute my bit to this place here.

@ Randall: none of the sites you link to in comment 64 explicitly exclude the possibility of a VEI 9. But that's just a detail. I'm sure in time (years, decades...) VEI 9's will be mentioned in more publications... if more will ever be found, otherwise the Fish Canyon eruption will probably be enough ;-).

By Gijs de Reijke (not verified) on 08 Feb 2010 #permalink