The Eyjafjallajökull eruption and you

I thought it was an information bonanza. After figuring out where decent seismic data was for Iceland (courtesy of this blog) I was able to get an idea of how things were working under the island.

As for the populace at large, I think the combination of experts who had no problem with discussing the mechanics of the event along with the webcams that showed up made for an enhanced learning experience for all of us. I know I certainly learned a lot. Being fan of geophysics and having reasonable data juggling skills made it into a highly entertaining event for me.

Of course I do have an obsessive-compulsive issue forming... I can't go a day without pulling down the SIL data to my spreadsheet... (if you don't get it, you miss it)

Tremendously informative site. I work for a major US airline and was monitoring many information sources as the eruption of Eyjafjallajökull and airspace closure unfolded. Your site is unique as it gives a perspective and view not found anywhere else.

I thought the whole eruption was a tremendous learning experience on many different levels. I was taking a volcanism class at the time of the eruption so Eyjafjallajökull provided an excellent, real-time, example of strombolian vs plinian eruptions and what causes them. The data that was made available to us on the composition of the ash at Eyjafjallajökull was part of a larger project on magma categorization.

We also talked about volcanic hazards of course, but more importantly how delicate our "advanced society" seems to be. Eyjafjallajökull erupted a relatively small amount of material, and yet, because of it's location caused a lot of problems for Europe. My class and I went through a quick study of all the active and dormant volcanoes near populated areas and made some simple ash cloud projections and we got a sobering look at the volcanic hazards right in our back yard.

In addition, I'm obsessed with volcanoes in general. I follow fantastic blogs like Eruptions and the SI/USGS Weekly Volcanic report religiously. All the webcams and pictures of Eyjafjallajökull were a lot of fun to get.

I remember the excitement and anticipation, based on Jon Frimann's posts. He was so accurate in his predictions and I was watching the Iceland met. office graphs several times a day as the quakes came up from the depths closer and closer to the surface. I was then so annoyed to be away from my computer when it first erupted, so that I had to rely on television and then catch up on the web-cam images after I got home. Then, to watch it grow, from a little fissure to a full-blown crater was an experience enhanced by the interesting mix of posts on this site, from experts and enthusiasts from so many places across the world. Thanks must go to all the people who helped to allow us to see the eruption in their photographs and on the web-cams. And most of all Thank You Erik for this wonderful website.

@Erik
I've already repeated it many times: I have got addicted to this blog, and even more, after eruption started from a crack in the earth at Fimmförduháls.
I have a lot to say and to thank you and all the people in this blog, and I hope I'll have time any soon to send you a looong e-mail sharing my experiences (and learnings) since then.
I've been trying to do all my homework on volcanoes, EQs, minerals and magma, but the more I study, the farther I am from understanding the whole picture. But I'll keep trying, if my time so permits.
Following @Diane, N Ca's example I've been doing my own geological researches here in Rio's most famous "postcards" and couldn't ever imagine how interesting this planet can be when carefully looked at from our backyard - thanks to you people!
Renato Icarahy da Silveira

#5 PS: Hope this thread will bring back people who shared the same excitement provided by this eruption... I miss them.

#5 PS 2: Is Katla going to erupt soon? (Hehehe) ;)
(This was supposed to be a joke, but just for the sake of information, there has been a couple of jolts under the glacier).

for me this site has been unique and given me so much insight to understand how everything hangs together.
With the Eyjafjäll eruption, I got first class information and to be able to see the eruption not only from the news, but also get insight from people that understands volcanoes and how they interact ..
so a big Thank you to all on this site,and Erik for being such a great sport blogging on this Great site.

Now I live In Aalesund, only a few hours from Eyjafjallajökull,I felt her as close as she could be,the air was filled with the smell of sulphur and it "rained" ash,those days it was possible,and i kind of felt that this Volcano was kind of our volcano too,.
The mass hysteria of the public not being able to fly and all the chaos on the Airports was kind of fun,but also very
Informative as it shows how small we humans are compared to Nature it self.. we are just mere dots in the big picture,even our planet are merly dust compared to the galxy we live in..

well I really would give a BIG HUG to all and Thanks from my heart,.

Its always fun and informative to be here, and read all the good stuff :)

In addition to vigorous exchange of information on the volcano itself, it stimulated what seems to have been a long repressed desire for some (me at least) to share haiku, folk tales, linguistic curiosities and engage in many other on-line community building behaviors. What impressed me most was the polite and civil tone to the conversation, even in the presence of many different opinions and perspectives. I don't find this on any other blog that I regularly access. Maybe that helps explain Renato's addiction (#5), you can open the comments section without having to anticipate a insults and pointless attacks between the participants.

found this about the tought Plume under Iceland

humm no link??

sheepers... Erik, when's the deadline? I could write a book on this. I 've got a big job to finish off this week but as soon as I get the chance after that I'll try to get down my thoughts down on paper at the weekend. Will that be too late?

From the UK perspective, it was the first time in recent memory that a volcano directly affected us, both with the stopping of flights and seeing volcanic dust on one's car in the morning. My university department had student field courses marooned in Spain and Singapore.

This site was invaluable to me in finding news. Having the site already in my RSS feed I saw the whole story unfold in nearly real time. I've done pieces for local radio before on earthquakes and so I got contacted by the BBC to do some radio interviews on the eruption (our volcanologist was away at a conference for part of the time). It did all my research starting from the links provided by this site and the interviews were done from my study with my laptop open at the most recent update plus the latest London VAAC maps.

The hardest thing was learning to pronounce Eyjafjallajökull.

Renato, we haven't gone anywhere and I still check Eyja at least once a day. Just have moved into lurking mode, as I have nothing to contribute scientifically or otherwise.

Erik, as I think I mentioned somewhere back a ways, this was my first and so far is my only online community experience, and I couldn't have stumbled into a better spot. With limited & very basic geological knowledge (to say the least) but a keen interest in things Icelandic thru travel and Icelandic friends, it was the perfect place to combine learning and keeping up. And thru you I still stay tuned to the world of volcanism. It has been a tremendous learning experience and seems to foster a real sense of community and collegiality. I wasn't tuned in before the main eruption of Eyja, more's the pity,( thus missed the lead-in,) so I don't have a sense of who the long-term members are, but I am extremely grateful to all who patiently shared in all ways from their knowledge and inspiration in this instance (Dagmar, I still smile over your drawing for us Eyja-followers. And Helen, your arch..?? Princess Frito, are you there?) Eruptions and it's folks and guardian have become the source of a daily dose of learning even if it will never be applied by me in the real world. How many people are fortunate(I use the word in its broadest sense) enough to in some way be a part of this sort of event in all its many human and scientific aspects.Thru Eruptions and its many links we have had a unique perspective.Thank you Eric and ALL.

I was vaguely trundling round the various blogs here after visiting one I have followed for a long time elsewhere and discovered a whole community obsessed with volcanoes - just like me :)

Not only that - I found an eruption with a name I still have problems pronouncing being covered like a blanket and completely fascinating.

I don't comment much because my geological background is limited to first year university level from about 17 years back but I always visit :) (I'm a fibre artist not a scientist btw)

viv in nz

Volcanic eruption, unique identifiers:

1. Near-real time provision of seismic, GPS, tremor recorders, and hydrology data from IMO, plus daily updates, photographs and videos from various sources.

2. 24/7 real-time visual monitoring by the interested public through a variety of commercial and noncommercial webcam sources, affording a 270+ deg perspective of the main crater and biaxial monitoring of the vent, day and night, and included infrared/thermal imaging.

3. Four continuous months of website volunteer eruption activity monitoring and reporting, much of it round-the-clock during intense periods of activity.

4. Website tracking of geologic and hydrological activity, before, during and after each eruptive phase included daily movies built from video feeds, posted video capture images, an indexed (wiki-type) web page of information links, constructed graphics of data, including rolling graphics, comparative 3-D box plots (color-coded) and depth/location and temporal analysis. Ash emissions were collected and subjected to particle size distribution and electron micrographic analysis.

4. Provision of background science, article links, technical discussion of historical geology and volcanology by IES, science professionals and knowledgeable laypersons.

5. Global recognition: the daily hit-rate to Scienceblogs website was almost entirely boosted by Eruption reader access, as shown by site monitor and search word statistics.

The blog audience (lurkers) monitoring posts here included the public, science agency and science technical professionals, news reporters, and government and industry officials.

6a. Proximal issue of glacier geography, ice mass-balance measurements and temporal shifts, outlet glacier recession and their relation to climate change and large climate ensemble latitude effects were explored in-depth and with technical reference annotation as a possible catalytic mechanism for volcano eruption timing (historical and present).

6b. Icelandic seismic activity centers - the two transform faults in N and S Iceland, Askja and Bardarbunga - background articles, theory, swarm historical trends and geological mechanics were introduced and explored in depth, to answer questions of daily and episodic burst patterns of EQ activity.

6c. Large climate ensemble effects, namely coupled ENSO-NAO-Polar Flow patterns that initiate and sustain atmospheric blocking. Theory and effects were introduced, explained, discussed (with technical references supplied). We suggested using this pattern as risk indicator of plume-path probability forecasting for Icelandic volcanic eruptions with potential to disrupt regional, continental and trans-oceanic air traffic.

7. A peripheral issue of geothermal field activity and it's potential relationship to Reykjanes Peninsula and South Iceland Seismic Zone EQ activity was raised, and has since been explored in the technical literature (Kelding et al, 2010).

Impacts: Very quietly, information posted here was seen to effect public responses by air traffic regulators during the ash crisis and afterwards, in airspace management of passenger backlog issues, regional airspace control oversight amalgamation (already planned, but accelerated, post flight-ban) and in hazard policy changes put into effect.

Indirect benefits:

Emerging applied science for surface and in-flight detection was discussed here and elsewhere. Extant technology (commercial and agency-owned) was quickly adapted for improved surveillance and industry advisory actions.

Topics brought up here were likely to be included in discussion between European and North American authorities on coordinating hazard and environmental policy on ash cloud risks and public and industry safety.

ESA, NASA, NOAA and others were observed to be responsive to requests made here for additional satellite and thermal image capture, analysis. Data was posted to agency websites. Agencies, private and commercial sites providing webcam video access were also found to be responsive to requests posted here for international access, camera positioning, and maintenance issues.

In the ash-cloud aftermath, realistic questions were raised here and elsewhere concerning purported versus actual economic cost and annual revenues impact to regional, transcontinental and trans-Atlantic passenger and commercial jet and tourism industry revenues.

This site also served as public record of response to a major volcanic eruption and ash-cloud over a densely populated region.

We all should thank the internet.
Thank you internet

Say "Thank you internet!"
Thx

OT: a 4.8 in the Tetons just a bit ago, about 100 km from Yellowstone.

Passerby, you would give a very scientific rundown on Eyjaf, now, wouldn't you? BTW, I mean that as a compliment. I think it sums it all up.

I had a fabulous time watching the eruption and I enjoyed the conversation and speculation of what the depth and position of all the quakes could mean and when it was going to go. Thank you, eveybody, for great contributions here and doing all the work that was done early on showing the quake models and all the graphs. I have learned a lot and I have all those who posted to thank so I say it again; thanks for the info and great discussion. Let's keep going!

Thank you Eruptions for teaching Non-Science folks like me about volcanoes. The blog provided invaluable information and links during the Ejya eruptions, (which is currently at 9:45PM EDST 8/4/2010, launching a steam plume about 8,000'). I would have never thought to watch an eruption live on a webcam. The excitement on the blog bubbled over for weeks in literary exclamation and mirth. The Eruption was hauntingly beautiful and your blog was completely enthralling.
Now I watch cams, earthquake plots, look at graviational variance graphics....which is asking a great deal from a clinical social worker.

From my point of view, this event should show the general public that the earth and mother nature is in charge of their lives.
This was a small event in geologic, meteorological history not to mention possible extra terrestrial disasters (meteors or C.M.E.'s). The general public must be aware of other historical potential disasters and how it will affect their lives.

OT 7.0 near Pago in Indonesia. The volcano is in A bigger caldera . This is worth watching IMHO.

The quake was not in the caldera however.

>Now I watch cams, earthquake plots, look at gravitational variance graphics....which is asking a great deal from a clinical social worker.

See? This is the intrinsic and incalculable value of a science blog that has a dedicated readership.

To change the way you view your world, that is the only way to impart 'mindfulness' to all inter-dependents that inhabit this Rock.

To change the way each of you view and interact with Terra Firma: therein lies the conjoint solutions to our most pressing global problems.

I, personally, love the site... I've always had a huge fascination with all types of geological events and the effects long and short term resulting from them. I've primarily been a lurker here reading the articles and comments and absorbing as much information as I can and I can say the commentary is extremely insightful and relevant.

During the Eyjafjallajökull eruption, the links provided to the mila and other webcams and other seismic sites were awesome. The frequent updates and resulting discussions were generally excellent. I usually check this site once a day to see if anything is going on as well as the usgs global EQ site. Love the blog will continue to be a frequent visitor.

"Did you feel you got something more out of the collective experience than just following the news events on normal media?"

Definitely. I've never been part of anything like this before. By following this blog, I was in on the story before the media caught onto it, and I was able to watch the story build while officials were downplaying it. The drama of seeing events build to an eruption was incredible, not to mention the drama of seeing Jon Frimann go up against the official experts and get the story right. An added bonus was getting to know the participants as real people. Rather than just exchanging information, people were talking about how the unfolding events were affecting or even consuming their own lives, and it was fun to watch the interplay between the different personalities involved. Not to mention how informative it was to be hearing from seasoned experts such as Boris Behncke. I would have felt even more a part of the story if I had been able to contribute more, but alas all I could do was refer people to a cousin's article on Pat Robertson and natural disasters.

All in all, this was what journalism strives for but so rarely achieves - information, explanation, drama, and a sense of personal involvement - yet done without artifice and seemingly without planning. Erik and his contributors had built a knowledgeable, dedicated, and friendly community, and then when events started at Eyjafjallajökull, everything was in place for an amazing experience to happen. Thank you, Erik, and thank you to everyone who contributed.

Not much to add to Passerby's description (#16) of the what, where, and how.

Maybe I can add a little to the "why', as in: Why was it was so interesting / addictive to follow this blog and to follow the eruption of the relatively minor volcano Eyjafjallajökull. (Of course, this is my personal account only.)

I think it was the empowerment and enabling aspects of the internet with all its resources that led a lot of people on a path of discovery - in real time - on a real event (with very real consequences). Therefore, a great 'Thank You' to the people and institutions of Iceland without which we wouldn't have had much to work with.

While it is normal for the geologists, volcanologists, and other related scientists to have access to ample sources of information if a volcano starts to show signs of unrest, the lay public had to wait for official announcements about the status of the volcano in question. But slowly more and more information is being made available over the internet for lay people to follow the events as they evolve.

Here, Eyjafjallajökull was still special in that this blog was alerted very early on (a great 'Thank You' to Erik about that) about an increase in seismicity before any official would acknowledge such a development. With all the information that was being made available, we were free to speculate (occasionally moderated by Erik and Boris), to formulate hypotheses, and to simply marvel at the unfolding spectacle.

Lastly, there is the aspect of the community that formed here on this site. On busy days/nights there were up to 200 new posts to read, a very lively and active discussion of events, updates -often by the minute - on the latest developments, and eye-witness accounts by people who live nearby or who visited the site(s). Other sciences can't offer anything similar (at least that I'm aware of) - just imagine a live report about the daily going ons in a biotech laboratory - how boring would that be. That's why this place became special and why I still come back every day to check up on the latest developments.

These are my two cents....

#14 @birdeyeUSA (isn't it supposed to be @birdseyeUSA? "rusty fingers", uh?) - Welcome back from "lurking mode". Still waiting for the others to show. ;)
I apologize, but I'll need more than one comment to wholly express this experience (in my case, the first time in a web community).
Looks like @Passerby (as usually) has said everything to it, but I think there's still much more to be "unwoven".
Even though it's supposed to be a scientific blog, and by all as such regarded, kept away from personal subjectivities, I daresay we can, with time, tell who is who, recognize the styles, the thoughts and almost "feel" the presence of people who we don't even know but for their nicknames and opinions - something really amazing.
I don't want to be sentimental over this, but I must say I've spent much of my leisure time (sometimes sleeping time) watching lava flows, steam plumes, quake plots and reading posts, and developed a certain degree of affection (?) to you guys whose names and whereabouts I don't even know!
Quite remarkable.
And thank you for your patience and forgiveness for my "killing" of Shakespeare's language so many times, but in time I also grew unaware of my writing skills (if there's any left)- for spontaneity's sake. :)
That's it (for now). Keep it going...
Good night everyone

This is a long story, so get a coffee or something before starting reading this.

This all started back in 2008, after the Mw6.3 earthquake that year. Following that earthquake I did notice small changes in earthquake pattern in Eyjafjallajökull. Given that data that I had (and IMO staff too), I did give a notice to IMO about this changes. But I also told them (according to memory) that it might be a while until something happens.

The pre-history of the Eyjafjallajökull goes back to the year 1994 at least. So the eruption would have happened even if there had not been any earthquake in the SISZ. But I have my suspicion on that the earthquake might have speed up the process that lead up the eruption. But that question can only be scientists them self, not by me.

For the longest time, nothing did happen at Eyjafjallajökull. Nothing but few earthquakes, and even for weeks there was nothing. But I was watching, and recording from the summer of 2008, as earthquakes from Eyjafjallajökull appear really good at my Hekla station most of the time.

Now, fast forward to the October of the year 2009. That month I start to notice repeated patterns appearing in Eyjafjalljökull earthquakes. This patterns where however unstable, and came and did go away at random times and even then nothing could happen for weeks in Eyjafjallajökull.

Things really started to get interesting on the 20th of December 2009. But then something really changed in Eyjafjalljökull. Then the earthquake pattern became repeated, lasting longer. But not yet continues. I had to wait for few weeks until that happened. I also started to record earthquakes from Eyjafjallajökull on my Hekla sensor if they where big enough. But many earthquakes that happened where less then ML1.0 in size, and those I did not record.

In the beginning of the year 2010 I see more pattern changes in the earthquakes happening in Eyjafjallajökull. They became ever more intense as the time passed.

Around third week of January 2010 I became sure in that Eyjafjallajökull would start erupting. The question now was just when, not if. When was just a question about time.

Around end of January everything did go crazy at Eyjafjallajökull. The earthquake count was up trough the roof in literal sense of the word. The intense of the earthquake was increased by every week almost, with few days or weeks where it remained low. The most intense earthquake swarms did happen three weeks before the first eruption. During that time in February (last week) and March I did record well over 2000 earthquakes happening in Eyjafjallajökull far as I can tell (my March folder has 4281 earthquake files, one earthquake is three files, my February had ~600 files I think. But I am almost done plotting the data from February already. The earthquakes in those folders are mostly from Eyjafjallajökull).

When the first eruption started I got the announcement via phone call around 23:30 UTC. The second eruption I did see it on the news in my phone, but I use to check for news during the night (too lazy to go the computer).

Rest is history as we all know.

More on OT Yellowstone:
Looking at this webicorder: http://quake.utah.edu/helicorder/moow_webi.htm
there have been quite a few aftershocks, which USGS is not posting to the map.

It was great to have a specific place (this blog) to go to to get both the latest information, as well as a timeline of events as they unfolded, AND links to other discussions ranging from close-up photos from locals to a discussion on Language Log on how a) people were pronouncing Eyjafjallajökull, b) how locals pronounce Eyjafjallajökull, c) how Eyjafjallajökull should be anglicised and d) some songs about Eyjafjallajökull.

I showed a significant portion of the above stuff to my non-net-savvy parents as well!

After the Chile quake, I went searching the web. First I found Science Blogs, & then Eruptions. Wow! So much information; so much discussion by folk who have quite diverse educations, & from all over the world. I remember the brainstorming, prior to the eruption, which went on & on between several readers here: crustal ups & downs; mantle plumes; pressure bubbles rising (w/ the tides? with the moon? over millenia?) Someone, Bruce Stout maybe, talking about historical tsunami evidence in northern Europe from a look at population movements. More influence from volcanic activity. The discussion about the hydro-thermal plant locations; the graphic depictions of how quakes propogate along faults (I don't remember what that is named, but I got it), how much & what kind of ash does it take to scrub a jet engine. One of the really cool parts to this blog is how the people like Erik or Boris or Ekoh, the folks who really know what's happening & why, let the discussions go, covering so much interesting territory, & only steer things from time to time. It was & is really great to watch the discussions unfold. I also appreciate how readers responded to "trolls", or to comments which indicated despondency (in this last case, perhaps lovingly sharing photoes of prized minerals found on trips into the great outdoors.) All the graphs, links, utube finds, sending us into so many directions. When away for a couple of days it would take hours & hours to catch up - didn't want to miss anything. I have never followed a blog before, but since I found Eruptions, I have found a few more. I notice that their readers & commenters are not so witty or polite, or frankly so interested in spreading their knowledge in such an understandable manner. I greatly appreciate the time & effort you must put into keeping the posts coming, Erik, even when out of town. If you have a cat, does it get fed as well? I believe this last is also one of the reasons so many have come to use this blog to stay informed. During the Eyaf days, where else could anyone find clear, intelligent & current information of the caliber which seems to be an ongoing event here on Eruptions? Thank you, all, & keep it up, please!

Well Jon, I think IMO/IES had a reasonably solid seismic knowledge and experience database to draw upon, with respect to EQ activity at Eyjaf.

Cumulative seismic history Feb 2009-Aug 2010:
http://hraun.vedur.is/ja/Katla2009/eyja_uppsafn.html

Activity can be clearly seen to pickup in frequency and magnitude in early January 2010. Note the summer months cluster/swarm of EQ activity in 2009. That's a clue.

First major post and following develop, March 3rd, here at Eruptions. Posts on this starter thread would continue through March 23rd and number close to 700. Socuel would provide useful cumulative plots and running timeline EQ graphics for more than a month.

http://scienceblogs.com/eruptions/2010/03
/increasing_signs_of_activity_a.php

A good time was had by all.

Good Morning,
I have been interested in tectonic activity of all kinds for a long time now, and came across "Eruptions" while looking for more info on the new Icelandic fissure eruption.

While I most definitely found what I was looking for on the day, I also realised that I had found a warm, intelligent and well mannered community that I felt I wanted to join and contribute to.

Six months and more on and nothing has changed. The topics are broad,the comments generally relevant and sometimes downright erudite, and the links almost invariably worth looking at. I have a host of interesting sites on my favourites list, a list of volcanic webcams I visit daily (sunrise on Nevado del Huila!) and input from a pile of people I'd like to share a weekend with.

Thanks Eric.

hi,

i am a volcanophile from germany and filmed the first part of the fissure-eruption at fimmföruhals. i was eyewitness of many eruptions, but this was first time at iceland and so very special for me.
after my first visit i tryed to visit the second eruption at eyjafjallajökull, but had bad luck with canceld flight for 4 times. i was sad about this, but hope that katla will following within month.

best regards, marc szeglat

The Eyjafjallajökull eruption and the related discussion on the Eruptions Blog (including the current thread) have been a wonderful occasion to learn about how a volcanic event is perceived by different people who share the same passion that I discovered during childhood. Obviously the eruption itself was an outstanding event, for the multitude of eruptive processes and products, for the transparency of multidisciplinary monitoring data, and for the impact it had both locally and regionally. It is a pity that the wonderful book "Volcanoes - Global Perspectives" by Lockwood and Hazlett was published just before this event, which would probably have featured strongly in it had the book been finished a few months later!
Besides the numerous fascinating and intriguing aspects of the Eyjafjallajökull eruption, it was quite an experience meeting (virtually) with all you folks here on the blog. Sometimes my loudly voiced concerns about other bloggers' statements caused a bit of friction, which I still believe is necessary once you professionally work in the sector. This is something that will come up again during future volcanic crises, and especially so once these happen in the country where I live and work, this extremely volcanic Italy.
I particularly appreciate to have gotten to know, and discussed with, our ingenious Jón FrÃmann, whom I wish to proceed successfully with his study of volcanic seismicity. Certainly the dynamic Icelandic tectonics and volcanism will keep him busy and all of us who are following the events and what Jón makes of them.
This blog also brought me back in touch with a few of you who had e-mailed me a decade ago when Etna went through one of its most frantic eruptive periods. Glad Marc Szeglat (#34) has joined the party, see you when Etna erupts next (I am not very sure that I wish Katla will erupt anytime soon, though on the other hand I think that volcano is totally overrated)!
Thank you all for being there and for the feedback, both positive and critical (it's all important, maybe the latter still more so); see you back on this blog soon, and greetings from sunny Sicily and a still drowsing Mount Etna

ok, just skimmed through the responses and it's hard to add much more, so I will save myself my weekend missive and jot down a few things here:

The main thing for me was that a blog is categorically different to any other existing medium for an event like this (stress that word categorically).

All our lives we have grown up as passive consumers of knowledge. We read books, we watch TV documentaries, we listen to the radio. We form weird theories in our heads and that is where they stay.. or at least that is where they stood until the advent of the internet. This blog turned all that into active participation.

From the moment the first reports came of a swarm happening and the intial heads-up of "watch this space" that were posted here, I experienced a number of things that were just sheer mind-blowing. I'll try and go through them chronolgoically but you can be sure I'll miss 50% of the fun:

1. Pretty early on I posted a naive question of why on earth you would get a rhyolite eruption on a spreading plate boundary and I got answered by Ekoh, a real-life volcanologist ;-) , within a matter of hours as to why a. this was not a stupid question and b. explaining how it could happen (key words: personalized response, interaction of total noobies like myself with absolute professionals, benefit for all others, I guess, due to public nature of innernet)

2. Following the rhyolite issue I got sent a thesis on the neighboring thorsmork ignimbrite by Heidi Ritterbusch, the author, which doubled my understanding of pyroclastic flows in one slash and gave me a fantastic insight into what Iceland was capable of (key words: same as 1. above plus one-to-one tuition of a caliber you normally only get at university)

3. Then there followed the input of Peter Cobbold, a scientist from an entirely different discipline who saw a high degree of symmetry in the seismic traces that he was familiar with in his work in biology (calcium concentrations in cells if I remember rightly) and the fascinating debates that ensued about what would explain the symmetry. For all our floundering I learnt an awful lot in a hands on way, discovering things for myself (that was certainly old hat to the professionals but for me totally new). For instance, the fact that we were probably looking at a number of cells or pods of melt rather than one textbook magma chamber that was primed for eruption. When Erik later confirmed that that is indeed how volcanologists view a lot of magma chambers, as multiple lenses of crystal mush, it was a bit of a Eureka moment. (key words: learning by doing, hands-on science, exploration). Bouncing our various theories off each other was fantastic fun.

4. Then there was the amazing lengths others went to such as Socuel and Korf to chart the activity and present it to us. Most of the discussion would have died but for this and I am eternally grateful to them. More to the point, you could actually ask them to do a chart for you! And they would!

5. Finally there was the amazing immediacy of the event, no better expressed than Jón's laconic one-liner: Eruption started at Fimmvorduhalsi, or words to that effect. It was almost like being there.

Seriously, it doesn't get much better than this. I could go on.. the web-cams, the service from IMO, the input from so many individuals,.. great stuff and an amazing experience.

Interesting about those aftershocks at yellowstone. Is there something brewing there? The recent CME ejection from a solar flare on the Sun is currently interacting with the earths magnetic field, I almost wonder if there is some slight interaction?

cripes, I nearly forgot!! The e-beers!!! (I still owe some people a few)

PS.. #31, Kathy, (smallprint) That was not me with the tsunami threat. That was Randolph Kruger, I believe.

Yellowstone is very calm at this moment. Less aftershocks than I expected.

@Bruce 38 My apologies. But not Randolph, either, I think. He joined the party later on. Bird species & floweering weed varieties of Iceland. Prose & poetry, from the Bard & homegrown. Now solar flare activity. The road goes ever on!

From my point of view, the Ejaf eruption occurred at about the same time as I was starting to try to get my head around the Earth's energetic self regulating mechanisms as a whole - and this eruption (and Iceland activity as a whole) has been fascinating as there has been so much data to view and try to correlate to observed events; very useful for someone learning 'on the fly'. It has also been fascinating to read all your comments and very gradually start to make some sense of the process of volcanism. I have a very long way to go, but still watch Iceland becuase there is so much available data to view - for example, does the Tjornes fracture zone have an erupting underwater volcano, or is current earthqueke activity heralding an eruption in the near future? Lots of fun! Thanks to all here for their patience.

To be honest, during the beginning and for that matter during the whole eruption I think that there was more information availible here on this blog than any other place. Media had its Katla mongering and not much information at all related to the eruption of Lady E.
But by reading all the posts, questions, theorys and answers from laymen as my self to fully educated geologists/volcanologists a better picture as to what was actually going on became clear. Not only at Lady E but on the whole mechanics of different volcanoes.

So a big thank you to all who has contributed to this!

Now a bit OT. Not that I am one of those Katla mongerers isnt ther a bit much shaking beneath her lately (past 48 hrs)? I am sure that much of it has to do with shifting ice but there are quite a few at larger depths. Between 7-16 km I count 7 tremors and there are a few at 2-3km as well. I know that its probably nothing without swarms of EQ´s but still...Abit out of the ordinary if you look at the period between Lady E calming down up to today.

WHY, BENEFITS & COMPANY QUARTERLY REPORTS

After Passerbys wonderfull writ on what was great with the site during the Eyjafjalljökull eruption I will just add my personal why, the benefits for me, and what it meant for me professionaly.

My Why on why I searched the internet for a great place to find information on the eruption. When the eruption started I was winding down my then engagement as investment director for a financial company at the same time as I sat on five boards, ie. I worked then in 4 separate countries on 2 continents.
What I am trying to say is that I desperatly needed to know when and where I could fly. I was actually not a volcano-afficionado when I started (although generally interested), but now I am hooked badly due to the "evil machinations" of Erik and others here;)

Thanks to the wonderfull and wonderfully accurate information here I got to all necessary meetings with a minimum of delays and reschedulings. And the meetings I couldn't attend I could well in advance book as videoconference-calls.

After a couple of days I started to sum up the info from here (which was far better then any other I could find) into small company volcano-letters that I circulated at my former job and to the companies I am a board-member at. The result of this was that all employees saved a lot of down-time at airports waiting for airplanes to lift off.

Quarterly reports for Q2 summed up the effect nicelly, in five companies the average net savings on travell during the eruption period was 150 K⬠per company in airfare without missing any vital personal meetings, and the investments in videoconference-call equipments is prognosticized to keap airtravell down in the future with 20 percent on average.
So from a company perspective the Eyjafjallajökull was a real benefit for the companies I have the honour to represent.

@ Lurking

can you make a graphic of the lastest earthquakes over katla?

the is a change in the dept of the quakes which makes me wonder how they would look on one of your plotts.

(several quakes betwen 10 and 7 km dept)

I lost track of the eq's at Katla for a couple of months. Those are deeper eq's than the usual shallow ones we've moslty been seeing and being associated with glacial activity. Maybe Katla, is becoming a bit restless? What's the usual eruption delay between Eyja and Katla? 1 - 2 years?

I'll just summarize, since there are already many interesting sequential reports. During the eruption, this site became a real-time classroom-with-many-teachers for me. Erik's photos and posts, plus the comments and links offered by dozens of knowledgeable participants, led me to do my own Internet research in an area that was new to me, to test the information I found in other sources (often incorrect or misleading), and to ask questions--and get good answers. For me, it was a remarkable experience that could never have been duplicated on a "news media" site. I'm a regular reader of this blog now, have added several new books to my library, and am paying more careful attention to volcanoes and earthquakes, both historical and current.

I took a look at the GPS data today, and I found GOLA, FIM2 and SOHO data interesting, as they seem to show a slight inflation trend. http://notendur.hi.is/runa/eyja_gps.html

As to why on the Eruptions blog? This blog got some paper coverage here at the start of the Eyjafjallajökull eruption, mostly because it was run by Dr. Klemetti, a fairly well-known family name here. I looked into it and never left after that: this blog acted like a hub for bringing in data from various sources, so following the goings on was easy.

Various people have given very good reasons for reading the blog, and I agree with them.

I have no comparison, but I don't think I'm very wrong if I say that the Eyjafjallajökull eruption is unique where it comes to coverage: web cameras, tremor plots, EQ data both on map and in tabular format, ash dispersion patterns both in satellite pictures and model animations, etc. Hard, verifiable data and this blog often offered interpretation of that data.

Of course the media coverage was extensive, too, but the quality of that coverage...

@44 and 45

I was wondering why no one mentioned the â10 km quakes.

Katla area, view north, 1 Aug 2010 to present:

http://i34.tinypic.com/ieedfk.png

Similar plot, but color coded for time. (lets you know which ones came first) No terrain topping.

http://i37.tinypic.com/243rtd2.png

Same dataset as #1, but view east.

i37.tinypic.com/33lfk0z.png

*note, copy past it to your browser, http stuff left off to avoid the Spam filter

First, I agree with everything everyone else said. (Yeah, what they said :-D)

My experience on this blog was, (and is) wonderful. That is, filled with wonder and awe. I've always been a lurker, but the friendliness of the community got me involved in the discussion. When I try to discuss plate tectonics or the mechanisms of volcanos with friends, I get that "what planet are you from" look. Here, I get friendly discussion and equal enthusiasm. People in other disciplines brought their skills to the table and gave us wonderful graphs and charts (Soquel and lurking). And I get perspectives from all over the world! How delight-full!

During the eruption, I always (from the time I woke up until I went to bed) had a screen open for this blog, and at least two of the cams on the vents. Obsessive behavior is putting it mildly. A big thank you to everyone who participated and to Mila for the cams.

I've learned so much from this site that I can't even begin to list the information. I've got hundreds of new bookmarks to scientific articles, USGS information sites and equivalents around the world, google translate, google earth, webcams all over the world. I've been inspired to indulge my passion for geology, and have started really reading on the subject. My view of the world around me has been transformed.

In terms of news, during this eruption I stopped watching cable and broadcast news. The irritation I felt about the lack of understanding of basic science and statistics was exacerbated to the point of revulsion. This site brought me news. Since then, I've been hunting for primary sources of other news on the web. Semi-successfully.

In terms of community, this is the best. I agree, the trolls are kept away. I'm not sure why. Perhaps it's because of a lack of response to the nasty guys. There was one case of a flame war. Certain members tried to mitigate the nastiness, but Eric finally kicked them off. I think, mostly, people who come here are trying to learn, and that shared experience is what keeps the blog civil.

Thanks @everyone. I'm grateful to you all (and as I write this, I'm feeling a great surge of affection).

Thank you Lurking

As always your plotts are quite informative

Speaking of community, my sweetie and I are heading out for Yellowstone next month. Does anyone have a suggestion for a good book on the geology of the place? I've got a pile of articles bookmarked, but a book is still the handiest way to carry info. Thanks all.

Timely topic. I just discussed Eyjafjallajökull in a summer course I am teaching. I spent some time discussing how the eruption became and internet phenomenon. I also pointed out how an equivalent eruption a century ago would have had a much smaller global impact, as there would have been no disruption in transportation. It's an interesting thing to consider - how our high-tech world is actually more vulnerable to natural events that would have had minimal impact in the past.

@52

Concidering that we just had an impact by a CME, and the auroras to go with it, could you imagine the impact on today's world of a CME on the scale of the Carrington event of 1859?

(reportedly, some telegraph equipment actually caught on fire from the induced currents)

Lurking, indeed that's another good example.
The more I think about it, it may not be correct to say that technology has made us MORE vulnerable, but instead we should say it has created NEW vulnerabilities.

Katla will erupt very soon.

hi all yes i agree with everyone else above with this site its the best one so far i came across with its info and right answers.As at the start when i first came on to this site didnt realize i was dealing with real people or experts in what they do? since may 2010 i have learned more stuff different things than ever so a big thank you to you all.
http://modernsurvivalblog.com/natural-disaster/katla-volcano-10x100x-ey… this site i believe came from Eruptions which shows the current/daily katla quakes had this bookmark for a while now

@Boris Behncke, Catania, Italy, I sure that Katla is underestimated volcano. The reason for that being the record is rater poor, even if there is a good record of the eruption over the past 1200 years or so. But there is little information on the size of those eruptions.

The Katla eruption in 1918 is considered rater small for Katla volcano. Given the break and the current time since the last eruption happened in Katla I am expecting a big eruption next time Katla goes.

Currently I am seeing more low-frequency earthquakes coming from Katla, and that is a bad sign in my opinion.

Jon Friman, I am a bit concerned my self..

last time Katla went of, we ended up with 20 cm of ash here, hope when she finaly sings, she sings with a light and gentle tone and not giving us a full symphony..
anyways, only time will tell.
And what seems strange to me ,is it seems like volcanoes breaths?? could I say that??
cause the Quakes seems comming in some patterns, first a period with quakes, then is seems silent, then a new perios of quakes..
is there a word for such behaviour, and am I right on this or is it just imaginations??

Thor, I noticed this too, but it looked more like a resonance pattern to me

@48 I did mention it but not in a "loud" way. ;)

Anyway if you look at the timeline all the deep quakes occured at roughly the same time. And at that depth it surely can not be Ice movement.

Isnt the most logical conclusion that it was probably cause by magma movement i.e intrusion?

@60

Not necessarily. Do remember that this is a border region between two rather massive plates. There will be some creaking.

I'm gonna leave this in the "dunno" pile, with a keen eye towards Jón FrÃmann's concern about low-frequency earthquakes. He has gear in the area and can see much more than we can.

Jón, good to be chatting with you again! About Katla, I think the general public does not at all underestimate this volcano, they're making a big story of it since many months. I personally might seriously underestimate it - but that's rather because I fear people get too fixed on one determined volcano when there are so many dangerous volcanoes on this planet. In my opinion, Katla is just one of many volcanoes that have a terrible potential. This is why sometimes I try to make people look in more directions than just one.
There may have been two small eruptions of Katla in 1955 and 1999, so it is not useful to believe that because so much time has passed since the last major eruption the next eruption will be more violent. There are volcanoes where the violence of an eruption is a function of the preceding repose period, like Vesuvius - the longer the repose period, the more powerfully explosive the next eruption. Other volcanoes don't seem to obey to that rule, like Avachinsky in Kamchatka which had a violent eruption in 1945 after 7 years of repose, and a much weaker eruption in 1991 after 46 years of repose.
Anyway Jón, given your record of being right when we were discussing, Katla will possibly erupt very soon and very violently, although for once I really really hope you're wrong :-D ... in the meantime I wonder what you would make of all the seismic signals we're getting here at Etna. One day we should invite you here.

@61

Yes i thought about that too but isnt the depth too shallow for tectonic EQ´s? I thought if there would be tectonic EQ´s the depth would be 20km or deeper?

@ Jón

The helicorders you have placed out would they pick up tremors from Katla? If so would smaller tremors on your instruments indicate a larger event? What i mean is would the seismicity "loose" strenght before reaching yuor helicorders?

Dont know if what I write is the same as what is in my head. ;)

I'm giving my vote to Parclair for making the most eloquent response so far! really well said.

Well, while we all busy watching Eyjafjallajökull over the last few months, Katla has been accumulating it's own quakes. For the most part, they have been somewhat ignored, not being indicative of imminent activity.

Now that Eyj has quieted down, and Katla seems to be doing a bit-o-rumbling on it's own, this plot is to serve as a placemark and reference for whatever analysis the knowledgeable people wish to make.

The bounding box was set up to try and exclude quakes that are outside the glacial area of Katla.

For the cursory observer, remember that this plot holds about 4 months of data.

http://i35.tinypic.com/28h21rl.png

@Lurking [65] -
Too few and too far apart still to indicate anything imminent. I think the Tjörnes site is more likely to go pffff, with the way the EQs are condensing there.

I'd like to know: 0.09 degrees latitude is quite close to 10 km in distance; what are the distances for longitudes at the Icelandic latitudes?

@Boris Behncke, Catania, Italy, Given the type and historical record of Katla I would guess that over the history there have been many small events like the one in 1955 and in 1999. In the end they might not play any role at all in regards to the size of the eruption that happens in the end. Katla is a lot harder volcano to predict the Eyjafjallajökull. Mostly for the reason it is bigger, but bigger volcanoes appear to have the tendency to be more unpredictable then smaller volcanoes. I do not know why that might be, but I figure as of now that it might have something to do with the dynamics of the magma chamber. Then to complicate matters even further Katla has seasonal earthquakes, it happens every year. It starts around middle of July and lasts usually to November or to December depending on how much the snowfall is on Mýrdalsjökull. In regards to inflation at Katla it is interesting to notice that it stalled, or stopped around the year 2003 or 2004. It has not changed much since. What that means I am all not clear on as of yet.

I don't like the fear mongering in the media about Katla. But there is a good reason to worry about Katla.

In regards to Etna, you can send me earthquake data in map form and I can try to give you estimate on it. But it would have to be broken down to a seven day (week) period. But I use that standard to work out what is going on. But that is only half of the data, as GPS data helps a lot on trying to figure out what is going on in volcano.

@Daniel_swe, There are few factors that depends on if I can record the earthquake or not. Those factors are, size, location, depth and type. Normal tectonic earthquakes are easy to record due to there high frequency nature. The harder ones I get from Katla are low frequency earthquakes. They are both hard to locate (IMO job) and to record.

@Kultsi, Askola, FI, TFZ is a fracture zone. It has no volcanoes. The only volcanoes close to are located at the south end of it, and in the north end. But not in the middle of it. So it is just tectonic earthquakes taking place there.

@thor, As Eyjafjallajökull showed clearly. The ash fall depends on the wind. Just hope that the wind direction is in your favor when Katla starts.

@Kultsi, Askola, FI [66]

According to http://www.csgnetwork.com/degreelenllavcalc.html

At 63.8°N, one degree of latitude is 111471.07 meters

One degree of longitude is 49630.00 meters.

If this is a duplicate, please forgive, at first the forum accused me of making too many posts in too short of a time, but it's been over an hour.

@Kultsi, Askola, FI [66]

According to www.csgnetwork.com/degreelenllavcalc.html

At 63.8°N, one degree of latitude is 111471.07 meters

One degree of longitude is 49630.00 meters.

@Kultsi @Lurking
I found a similar figure browsing with Google Earth's ruler from -20º to -19ºW at 63º 62 N (roughly Eyjaf and Katla's lats.). One degree = 49,40 km. But that's Google's not Lurking's precise formulas. :)
@Daniel_swe I think I had the same question in mind, but didn't quite know how to formulate it. From Jón's answer, I understand that his calculations are not based only on what we see on his Hekla's helicorders, but from IMO's data as well, which are available at the site. Is that correct, Jón?
And it would be very interesting to follow Jón's readings on Etna's plot.

@64 Bruce Stout. Why, thank you.

#69 following the same procedure I got:
1 degree at 60º 52'N (Askola, Finland) = 54,92 km
1 degree at 23ºS (Rio, Brazil) = 102,75 km
Lurking?

#70 @parclair I agree with what Bruce "said". ;)

@Renato Rio, I have to use data from IMO network, as my sensor network is not good enough to locate earthquakes, and I don't have the software or the hardware for the detailed information that I need to figure out what is going on inside the volcano.

I don't however base my judgment on one set of data. I try to use what I can.

#73 Thank you, Jón, that's what I believed. All I hope is that when it comes, the winds will blow into the right direction. :)

Greetings everybody!!!

As I was reading all the posts, I kept saying to myself "darnit it! I was gonna say that!" :)

I really can't add much more to what has already been stated so eloquently. I feel very lucky to have found this place when I did; there's simply no other place that has as many pleasant, funny, extremely intelligent and curious people.

I still try to find the time to lurk at least every other day. In fact, I had a question about solar flares a couple of days ago and the first place I thought to go was here but then I thought "naw". Silly me. Then again, today I was reading about "spacequakes" and though of the gang so I headed here to say Hi!.

Silly me! I should have known you guys would be talking about these things too! And that's what I love about you guys - you all have a such a strong thirst for knowledge about, well, everything!

Ok I also miss cuddling with Gordys on our cyber couch while watching Mother Nature in all her fury, the strange cravings for breakfast at 11 pm as the sun rose on our Lady Eyja, guessing when Helen's Arch might collapse, the many ways we would entertain each other during lulls (opera, trivia, jokes, etc.). Gosh, I could go on, so I won't ;)

It truly is a special place that puts someone like me at a loss for words to describe my experience here.

Thank you Erik!

I can't suppose that this comment is much of an addition to the above, except as another expression of "Thanks" and "Wow, fascinating!" from a non-scientific type. Laypeople who are interested, in a lay way, in natural phenomena often come at the topics from an esthetic angle, and/or (as in this case) because they want more specific understanding of something exciting that's happening right now. I got both kinds of satisfaction from this blog - the links to the Icelandic sites and webcams and to other visual resources (that fabulous photo essay on boston.com's bigpicture, and the photos of eruptive lightning, for instance), and the expert discussion here that sent me scurrying to look up some of the specialized vocabulary. All that plus the rounded viewpoint that took issues like the air travel ban, media influences, etc. into account, and the real sense of community from reading the comments... seems to me this is science blogging as it should be, as least from this non-pro's POV. I can't share the enthusiasm of, say, a group of theoretical physicists, but here I was able to feel that I had a fundamental understanding of what the excitement was about. So - Thanks, and Wow, fascinating!

Correction: Thank you to all of you! :)

@Renato Rio

"...Lurking's precise formulas..."

Thanks for the accolade but they aren't my formulas. I'm just parroting what that site spit out.

If I were to actually calculate the distance of a great circle path, I would use the angle in radians x sphere radius, but that is only as good as your sphere radius measurement... and the Earth is not a very good sphere. So, I cheat where I can or use a few Excel formulas I found at

www.movable-type.co.uk/scripts/latlong.html

Really handy thing during hurricane season. As for plots, you ought to see some the really wild ones I made last year that tracked the landfall aimpoint vs various coastal cities as each update came out. I don't think I'll be doing that this year just form the workload aspect of it.

I ought to add that I come back here every other day or so, too - - volcanoes may be awesome and quivering with the excitement of potential danger, but it's also strangely calming to keep track of grand, complex events that change every day and owe nothing at all to human passions and foibles. If we all vanished tomorrow, or if we had never evolved in the first place, the earth would still shake, and the steam, ash and lava still rise.

I warn iceland.. take cover soon... it starts with a new moon.

#75 @Princess Frito!!! I knew Erik would find a way to bait you back. Just in time. I thought you were drowned somewhere in the Mariana trench. Good to hear from you!

#78 @Lurking "I'm just parroting what that site spit out." I'm most thankful to all your "parroting"!

#79 @Mary Ellen: I feel very much the same way. And maybe that explains why we became so close, yet living so far apart. This kind of understanding could mean a step forward to human evolution.

Hello all. I had to pop in on this one. Been away from home for almost a month and won't be back for another few days, so I haven't been around except for a little lurking now and then. (Does Lurking have little lurkers? Or would that be lurkinglers?) :)

Admittedly the information posted here has been way over my head, but that has not stopped me from trying to learn. Until Eyjafjallajökull, I have never really paid any attention to the geological side of volcanoes, only their historical impact. If I had to rely on the news media for good information I never would have kept following what was happening. But this blog and the information, analysis, even educated guesses, reeled me in and I couldn't stay away. I even created a blog on a weather site to disseminate information. Little did I know it would be visited by people from 43 different countries.
But beyond the scientific aspect, I think what really kept me here and posting was the people here. This is a place where there really is no stupid question. People have given freely of their knowledge to those of us who know little or nothing about volcanoes. And then there was the brief interlude when we couldn't see anything that haiku's (and one limerick) became the filler so we didn't lose touch. We have had language lessons (it's not poro, it's thoro). I could go on, but you get my point I believe.

Thank you Erik for this blog and thank you everyone else for sharing your knowledge.

@81 @Renato!!

Just when I thought I was out... they pull me back in!

And every day I still keep loyal watch over this camera at Taal Lake for someone here and I don't even remember who it was anymore!

http://www.mycam-asia.tv/cams/philippines/luzon/batangas-taallake-yc/di…

@Dan Margueritas, Florida!
Hope you guys keep dropping by even just to say hello.
@Everyone
According to EMSC there were two quakes that were not mentioned in USGS reports: a 5.0 in Mianmar and a 4.7 in Vanuatu.
http://www.emsc-csem.org/#2
And another 3.7 in Long Valley.
Solar flares? >:-}

#83 Hehehee! YRH

@83 Princess Frito-- thanks on keeping watch over Taal for me. Heh, I'm back, but never know when I'm off again. (family crises). Since Taal's been downgraded, I guess we can move onto other things. Altho' I do like the view.

I've been watching the AVO cams lately, the weather's been good enough to see the volcanos there.

Beware the Spacequakes!

http://science.nasa.gov/science-news/science-at-nasa/2010/27jul_spacequ…

@86 parclair I was 99.9% sure it was you but I didn't want to embarass myself in case I was wrong since it's been a while. That Taal cam is kind of soothing, isn't it? I wish you all the best and pray that you and your family have the best possible outcome to your situation. :)

BBC news article on geomagnetic snapback:
www.bbc.co.uk/news/science-environment-10880852

2 large CME events, yesterday and today
www.spaceweather.com/archive.php?view=1&day=04&month=08&year=2010

Major jump in USGS Global EQ Map events: 150%, 18 hours.

An interesting overlay graphic:
This plot
www.solen.info/solar/images/solar.gif
with this semi-transparent layer
hraun.vedur.is/ja/Katla2009/god_trem.gif

Remember the timing lag: 3 days

Yellowstone uptick: geothermal/pore pressure with tectonic response.

Tanzania quake: geothermal/gas exploration

For Kultsi: Tjornes - geothermal with occasional magmetic fissure flux.

Hydrothermal fluid flow within a tectonically active rift-ridge transform junction: Tjörnes Fracture Zone, Iceland. J GEOPHYSICAL RES 115:B05104, 2010. doi:10.1029/2009JB006640
www.agu.org/pubs/crossref/2010/2009JB006640.shtml

@29: What you describe about October 2009 is eerily similar to what is going on at Katla right now. Any significance to this?

So...I concur with Kultsi, a reasonable probability exists for a larger shake, 5.3-6.3 Mag on the Tjornes Transform Fault, 1-6 months, probably sooner over later.

Chance of Katla erupting: remote at present.

@89 Passerby: Thanks for the great links. The bz's direction just turned south (although weak) so I'm running back outside with my trusty digicam in hopes of catching some of the Lights. Wish me luck!

Don't need luck, except maybe with respect to cloud cover: aurora was photographed as far south as Iowa last night.

Now: Kp=6 (storm).

@93 Passerby - Kp=2 now, no?

http://spaceweather.com/

Yes, cloud-related luck. :) Cloud cover looks 2/10 scattered. Another band on the way, but lots of stars are visible right now. I'll try again in 20 minutes.

I'm at about 55 degrees magnetic lat - about the limit where the chances are 50/50 from what I've read)

It's going to be a long night :)

@93 Passerby I believe I need a Kp of 6 - 6.5 at my latitude.

Bz switched from north to south and increased from 1.7 south to 2.3 south in the past 20 minutes. Should it follow then that the Kp will also increase (and thus increase my chances)?

Darn it! From spaceweather.com:

"The show is over ... for now: Geomagnetic activity has subsided to low levels and the aurora show of August 3rd and 4th has come to an end. "

But for the sky's next act:

"Mark your calendar: On Thursday, August 12th, an alignment of planets in the sunset sky will kick off the finest meteor shower of 2010, the Perseids".

*Sigh*

Sorry, it was Kp=6 when I last checked a few hours ago. We should see a corresponding decline in EQ activity on the USGS global and US maps.

Well, I wasn't going to go there, but I did do a plot earlier today. I dropped the K index chart in as the background of one of my global Earthquake Power plots and scaled to match the timelines. This is for Mag 4.5 and higher as reported by the USGS. The K index plot background is from solarcycle24.com

http://i34.tinypic.com/2hdnscp.png

Whoa Lurking! As always, you rock!

Whoa Lurking! As always, you rock!

If I said it once, I've said it a thousand times - Lurking, you r..

No but seriously folks, sorry for the double post. It seems there's a glitch tonight.

@Passerby - No probs. Thank you again for the info.

Rock or not, I don't have an explanation for it. Looking just at Iceland, you don't see it. But then Iceland has a whole lot of other stuff going on that will affect the activity, things like volcanoes with upset tummys, shifting plates etc.

http://i35.tinypic.com/4t1yjn.png

Passerby or someone else on here may be able to explain it... I've only done one CME event verses Quakes, and that doesn't make for a good indicator.

@Lurking @Renato -
Thanks for the numbers! What I was looking for was a good grid for the plots, and around Mýrdalsjökull a spacing of 0.09 degrees for latitude and 0.2 degrees for longitude would give a 10 kilometer grid close enough for plotting purposes - that combined to a similarly spaced depth axis would give plots with only slight distortion.

@Passerby [89] re. geomagnetic storms & tremor plots

Could the Occam's razor here be that the recording devices sensitive enough to pick up a man farting would also record the changes in the magnetic flux? They are, after all, electro-magnetic pickups.

While rummaging around for data to get an idea of what things are like under Mt Hood (historically) I ran across an odd... "thing." I don't know what it is, other than a collection of quakes somewhat North of Madras OR in the in a river plain south of the Columbia River.

The location is 45.1173 -120.9467.

Any one have any ideas?

http://i34.tinypic.com/2ywa649.png

( Note, the quake data is from 1975 until present, data from teh ANSS catalog quake.geo.berkeley.edu/anss/catalog-search.html )

Hello all,
Just wanted to join in and add my name to those before me who have expressed so well how much they have learned and what enjoyment this blog has given them. I stumbled upon it in April when the eruption was well under way and immediately became addicted to it (much to the bafflement of my family), religiously watching the cams and the tremor graphs, all at the same time, and reading the fascinating comments from learned experts and lay volcano enthusiasts alike. Besides experiencing the beauty and drama of such a big show of Nature, and learning about Icelandic tectonics, magma intrusion, ash components and so on, I particularly loved reading all the other contributions, the haikus and the other volcano-related literature references, the information about language and culture and even the posters who simply expressed their awe and wonder or shared their discovery of rabbits and bears in the plume.
All in all, it was a wonderful experience enabled by the Internet, empowering people to watch and share their experience in real time as the events unfold, and by all you great people who have made this possible.
I continue to check the blog every day and learn about other volcanoes, but I still find it oddly soothing to just gaze at the Thorosfell cam (even when itâs foggy).
Thanks to everyone!

I wouldn't have been following news of Eyjafjallajökull's eruption at all if it wasn't for your blog, actually. And I didn't follow the media reports at all. Too much sensationalistic crap. Here, I could get far better information without the ZOMG WE'RE ALL GONNA DIIIEEE!!! hook, and in a place where I could be sure that the science was accurate (and if something was reported incorrectly, you'd correct it as more information became available).

Before Eyjafjallajökull, I'd never really considered the implications of a volcano erupting under a glacier. That stands out far more than the impact on air travel for me - it's obvious a lot of volcanic ash in the air is going to have an impact on jets. What we don't encounter as often is what happens when a volcano blows under an ice sheet. Learning how that works and seeing the result here was the best part of the eruption. Sorry, Iceland! ;-)

You did a brilliant job, Erik. Thanks!

@67 (Jón):

Actually I for once have to disagree with you Jón. There are 4 Volcanos in the area that we see on this link.

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/tjornes-small/

You have one submarine volcano that erupted in 1868, another that erupted in 1755 (Kolbinsey Ridge Volcano), and of course the 2 dormant (or dead) volcanos of Kolbeinsey and Grimsey.

The distance from the 1755 volcano is just 10 kilometres away from where the quakes are occuring, they follow the fault line, and as Lurking has proved, they make up a clear tube pattern. Secondly, both the 1868 and 1755 eruptions where in Fimmvörduhals style (I didn't want to use the word Laki-style for so many reasons...), ie. long rift wents. So I have no problem with seeing a possibility for a new rift opening up at a slightly other part of the FZ than the KRV proper.
For all we know it might allready have been rift-eruptions on the site, but it has not been recorded. Actually the sea-bed in the area looks decidedly odd when I look at the marine charts for the route from Grimsey to Husavik and Akureyri. There are really "flat" areas marked as stone bottom there, which might be indicative of old lava-beds.

I am not saying that you are not right, I just want to throw in a little bit of a spanner into the machinery. For being Iceland TFZ is unusually volcanically quiet, but...

@68 Lurking:

In a perfect world you would be correct, but...
For some reason they whey back when decided that it was easier for sailors if a latitudinal degree was 60 minutes times the nautical mile. So a lat degree is actually 60 X 1852 metres = 111.120 metres.
This was all very well back in the days of the clippers, but today with the satellite tracking positioning systems it is a bit of a bother since they present your figure (which in a way is absolutly correct). So instead your little GPS recalcs it into the older number so it fits the maps.
The original problem comes from the old calculation of the earths circumference which gave the result of 40003,2 kilometres. But since nobody changed it the problem is still there... I don't know if some modern land-maps use the correct number, but all naval-charts use the original 60 nautical miles per degree lat.

Hmm not even one little shake. Its almos eerie how quiet Myrdalsjökull is now. :) Not even some trembling from shifting ice.

24 hours of complete silence and counting.

@ Kathy # 40:
For want of loads of better things to do (like work) I went through the posts again just before the eruption (great reading btw !! Did anyone mention James? He was really on the money!!)

... long story short.. you're right, it was Micheal Cerulli Billingsley who championed the tsunami threat, not Randolph. Apologies all round.

good morning all - I think this thread has just demonstrated what makes Eruptions so special. It feels like a family reunion....

those of you who have mentioned the Mila cams and other live links (alas, poor vodacam) have hit a uniting factor, without them I have a feeling that a lot of us would have checked from time to time for discussion, links and updates, but with them, we who are not scientists became truly involved. That's a unique privilege. Thanks, Mila, I hope Thorocam stays up even if the mountain stays quiet, we can always keep track of the glacier...Anita@108,'oddly soothing,' I couldn't agree more. (There's a caravan of white vehicles out and about this morning.)
'Sue's' pbworks links page was wonderful.

Boris,we'll join you at Etna for sure!

hi all first start with Colin looking at the weather maps T storm Colin might curve round and head towards Iceland or between Greenland and Iceland in the coming days you want to keep a close eye on this,and the Atlantic ocean is looking very active from the 20/21 August

This is a question for all of you who know more than me.
This is all in theory of course!

What if there was a large magma chamber beneath myrdalsjökull which during the past
years/decades was slowly but steadily filling up. This would for sure create some minor
tremors, EQ´s and such I assume?

What happens when it is filled up completely? Would the EQ´s cease and the minor tremors from strain
in the bedrock increase as the chamber began pressing upward? Or would there simply be
even more and larger EQ´s?

Around 2 days ago there was a few deep EQ´s (7km or deeper) on the southern end of the glacier. Since then
the EQ´s has come to a complete stop (almost).

Could it be that the chamber has been "topped off"? I realize that its not just a big hole in the ground
but rather a mix of magma/solid and so on.

Trying to educate myself a bit more and I find it more unusual with a complete lack of EQ´s than the prescence
of such events... :)

@Passerby 89 Thanks for the links - I stand corrected & furtherly (:>) educated - not solar flares.
@ Bruce Stout 112 See this is just one of the coolest things about this community of curious folk - leaving no stone unturned. Thanks!

@Carl, The only known volcano close to TFZ is at it south end. It last erupted in the year 1868, that is confimred anyway.

http://www.volcano.si.edu/world/volcano.cfm?vnum=1703-10=

Here are good maps of TFZ and it's movements.

http://sites.google.com/site/jacquesangelier/platedivergenceiniceland

Kolbeinsey ridge is a diffrent system, and is the system that starts where TFZ ends. There are at least one active volcano. There might be more there. More information, http://www.volcano.si.edu/world/volcano.cfm?vnum=1705-01=

The combination of an unusually articulate and interesting professor-blogger, along with current data-events covered from almost every perspective, along with exceptionally gifted commenters makes for a blog I visit daily. I have followed more links from Eruptions to fascinating research than from any other source. Eyjaf... news and discussions gave blow-by-blow, moment-by-moment coverage that deserved its tremendous following. What many scientists and "lay" people like myself now know about volcanic processes and their effects on humans has been tremendously expanded. Finally, what we do not know today, and what we may never know, has been emphasized and adds a humbling element to the great technological strides in volcanology knowledge. I thank Erik and all those contributing to Eruptions.

@99, Lurking. Answer to your query on the origin of seismic activity south of Madras, OR.

Smith Rock. 'The main vent feature of the Lower Crooked volcanic field is the large Crooked River caldera, which erupted the voluminous Tuff of Smith Rock at 29.56 MYA.

Field trip guides to the geology of the northern half of Lower Crooked Basin, Crook, Deschutes, and Jefferson Counties, Oregon - Overview.

www.oregongeology.org/pubs/og/OGv69n01-LowerCrookedBasinOverview.pdf

THE CROOKED RIVER CALDERA: IDENTIFICATION OF AN EARLY OLIGOCENE ERUPTIVE CENTER IN THE JOHN DAY FORMATION OF CENTRAL OREGON. 2007 GSA Meeting Abstract.
gsa.confex.com/gsa/2007CD/finalprogram/abstract_120471.htm

Geologists discover Oregon's largest volcano, the Crooked River Caldera. Local news article, March 2008.
www.thecreswellchronicle.com/news/story.cfm?story_no=5008

www.youtube.com/watch?v=a4z5jK85Hs0

hi; Nasa-Great ball of fire image of the day
http://www.nasa.gov/multimedia/imagegallery/image_feature_1732.html
Katla some photo's going back 1997/99 and info
http://www.earthice.hi.is/Apps/webobjects/HI.woa/wa/dp?id=1011072

Above post for #107. Interesting plot, post 99. Thanks, Lurking.

http://www.earthice.hi.is/Apps/WebObjects/HI.woa/wa/dp?id=1011072
Katla i hope this work i missed some caps

Thanks for the links, Leon.
A report posted in Icelandic shows the huge amounts of tephra and water/steam ejected from Eyjaföll as well as melted ice.
"100 million cubic meters of ice melted in Eyjafjallajökull"
http://www.hi.is/frettir/100_milljonir_rummetra_af_is_bradnudu_i_eyjafj…

Thanks Leon and Renato.

For those who can't get enough of Icelandic webcams, Mila has added a few more! Now you can view a geyser, watch people swim at the Blue Lagoon (no men in thongs please!), or watch traffic in Reykjavic. They've added back in a cam on the south side of Eyja but it's not currently working.

Fill your boots!

Of course, a link would probably be helpful ;)

http://eldgos.mila.is/english/

#125-26 Thanks, Your Highness. Leon and Kultsi had already provided us with the link, but this one is a good reminder.
My compliments to the Icelandic dietary habits - most people swimming in the Blue Lagoon appear skinny and fit. A little bit more of suntanning would help, but then again, congratulations for their bravery (weather maps show max temps of only 11º C at the site!).
People browsing at Yellowstone Park should take it as an example.

Things are starting to shake up at Yellowstone, check out this link.

http://www.quake.utah.edu/helicorder/imw_webi.htm

I really enjoy this site, all of your comments are great while being 100% better than the news.

Thanks everyone.

but also thankyou to you all, so much info! i have this link sent to me earlier Iceland should take a look whats coming but still it could miss you
http://northeastquadrant.blogspot.com/

Wow, I bring up Eyjafjallajokull and suddenly we have 100+ comments! I was hoping to get a few comments to use for the talk, but this is overwhelming. Thank you all for the kind words about the blog, but really, I'm just a moderator, you are the community, to you should all give yourselves a hand. I should be able to post a PDF version of the talk on the blog, so look for that sometime in September.

@ Passerby [120]

The cluster is actually north of Madras, and using your reference data, seems to be under the Mutton Mountains. It also seems to be associated with that structure, being in an area that would have likely been under the northern reaches of that caldera.

What I find interesting, is that the the crooked river caldera predates the flood basalt event by â10 myr, then there was the CFB event, then the caldera march up the snake river plain, ending with Yellowstone.

Thats the cool part about this site, it's almost impossible to come here without learning something.

The only suggestive point of reference I could find was to the South.

I found an interesting explanation other than the Yellowstone hotspot. That would be: subduction zone backwash upflow at volcanic 'roots' (eg., the caldera).

The Oregon High Lava Plains: Proof against a plume origin for Yellowstone?

www.mantleplumes.org/HighLavaPlains.html

This mechanism is mentioned in technical discussion of the Newberry Volcano (see wikipage).

In seeking information on volcanoes, I came across this blog, which is rich, relevant and interesting so it is magic because every day I visit him as a friend. Thank to all. Merçi à vous tous. Sorry for my bad english

Well, Erik, you are still the one who made the decisive difference by actually encouraging participation and then treating everyone with respect, no matter how stupid the question (ok, there are no stupid questions, right? ;-)

This started way before Eyjaf with the mystery volcano series and other events. Without these signals from you a lot of people (like me) would never have dared to participate here. So, seriously, hats off to you. You've created something particuarly special with this blog and I hope a lot of other teachers take you as an example cause you can't do it much better than this.

@Passerby

If by backwash, they mean the turbidity set up by the loss of the Farralon plate, I can agree with that. Roughly 20 to 30 myr ago is when the western side of it started dropping under the North American plate. Things were probably a bit chaotic then.

@135: Wrong plate. There is recent seismic data for the The High Lava Plains that argues for upper mantle partial melt, but the mechanism promoting upwelling is as yet is unknown.

The first paper cited below suggests lithosphere tectonics and not aesthenosphere flow is responsible for HLP volcanic activity, but the second argues against this and suggests aesthenosphere turbulence, using the same method (SKS-splitting).

Origin of the Newberry Hotspot Track: Evidence from shear-wave splitting. Xie and Allen (2006), Earth Planetary Sci Lett 244:315-322.

>The average fast directions ENEâWSW to the northwest are consistent with generation by mantle shear parallel to the subduction of the Juan de Fuca Plate, and the more EâW fast directions to the east are perhaps due to shear caused by the Basin and Range extension.

Shear wave splitting and the pattern of mantle flow beneath eastern Oregon. Long et al (2009), Earth Planetary Sci Lett 288:359â369.

> We infer from the large split times and homogeneous fast directions that there must be significant active flow in a roughly E-W direction in the asthenosphere beneath the HLP; this inferred flow field places a strong constraint on models that seek to explain the young tectonomagmatic activity in the region.

The area to the north, the Blue and Wallowa Mts, are apparently more complex.

earth.geology.yale.edu/~mdl2/papers/long_et_al_2009_epsl.pdf.

As the slab (Farralon) drops downward and to the east should there not be a flow from East to West as the existing material flows back towards the direction that the slag came from?

A short time ago in the responses to our guest poster Dr. Ed Kohut, there were links to articles that suggest that as a slab lands on the next boundary layer plumes may be generated from the displaced material as it is forced upwards.

One would think that if plate/slab dynamics are a representation of solid/fluid interaction in ultra slow motion that there would be a reverse current as it sinks.

The papers I cited mention the Juan de Fuca, to avoid confusion. You're not incorrect at calling it the Farallon plate, but the subduction forces arise from its small remnant.

Reconstructed past plate history, Univ Wisconsin:
www.uwgb.edu/dutchs/platetec/kula.htm

Regional general direction of flow is said to be from the Juan de Fuca Plate; the Farallon plate is largely subducted under the NA Plate. The Juan de Fuca, one of the smallest tectonic plates, is a Farallon remnant. Eg: most of the Farallon plate is folded deeply under North America.

svs.gsfc.nasa.gov/vis/a000000/a002400/a002410/

en.wikipedia.org/wiki/Juan_de_Fuca_Plate

I came across this in my alum magazine - no answer given - a geology 209 course on natural hazards. Fun, perhaps, for some of you (not me!) My addition is, with given parameters, would it overrun Hvol or Thoro cams. Possibly there are some missing parts, I don't know enough to tell.

"Example of weekly problem set:
In a volcanic eruption the tephra (...) reaches a maximum elevation (ho) of 10,000 feet from the vent of the volcano.

a) what was the initial velocity of the tephra as it was ejected (assume..(a vent) elevation of...2500 meters.) To find the velocity use the kinetic energy equation and set the kinetic energy of tephra as it explodes equal to the total potential energy the tephra has as it stops at its maximum elevation.
KE=(1/2)mv2
PE=mgh

b) once the tephra starts flowing down the side of the volcano it will start to lose its total energy through friction as a function of the horizontal distance (x) away from its starting point. The total energy, as a function of horizontal distance, decreases as:
Etotal(x)=mg(ho-Ax) + KE + PE

where x is the horizontal distance away from the summit and A is the friction coeffiecient, A= 0.2. What is the maximum total distance the tephra can travel? (Hint: the maximum distance is reached when the tephra's velocity is zero.)"

That pretty much fits with my notion of it. The logic I used in associating the Farralon demise with the Crooked Creek/CFB/and Snake river march have to do with the timing of Farralon's demise. (â30myr)

The CFB and Yellowstone aspect of it arising from the "turbidity" from the tail end of the drop. (Sort of hard to call it turbid when it's going so slow)

Tout a été dit, non?
I'm totally addict....
J'adore...
Thanks Eric,Thanks Community
Mumu of france

Regarding feed-back request:

Since I only discovered the blog May 2, I missed most of the Eyja excitement. Besides the general coverage and discusion, I also liked the photos and especially the many great links to more sources of information. Additionally, I appreciate that someone unknown to me gave a helpful reply to a question I asked in the comments area. :>)

@birdseyeUSA

Wouldn't this require the ability to see the top of the tephra column? At what point do you call it ash being carried along on prevailing winds as opposed to tephra that falls back to ground?

Or, is the level that the ash can be found at an indication of how high the tephra was thrown?

(general curiosity)

#139 @birdseyeUSA Interesting question. But don't you think it is a purely theoretical one? I don't think that all these formulas work in this case. Maybe this is a stupid statement of my lay opinion. But further I go:
1. "maximum elevation (ho) of 10,000" - I agree with Lurking: how can you tell it precisely? Ok. it's a given figure. proceeding...
2. "...as it stops at its maximum elevation" - does it stop only because of gravity or atmospheric pressure, temperature and winds play a significant role? don't know the answer.
3. "...once the tephra starts flowing down the side of the volcano" - now I think this is the weakest point. What kind of tephra? Lava? Pyroclast flow? Ash? Lahars?
4. "...friction as a function of the horizontal distance" - that sounds weird. or maybe it's me. How steep is the slope, how viscous the magma?
I think we lack some information here, don't we? Please, tell me if I'm wrong.
Amusing, though. Thanks a lot.

500 feet :)

No wait! 50 feet. Not sure if my decimal is correct :) Ok my final answer is 250 feet ;)

What did I win?

@Renato I'm thinking this is a trick question (ergo, the fun factor). ;)

If the tephra reaches 10,000 FEET ASL, and the vent is at 2500 METRES ASL, the vent-to-maximum-tephra-height distance is only a measly 250 feet.

Am I right, birdseyeUSA?

@Renato,Lurking, Your Highness,you win my undying admiration for even trying out an answer! : ) As I said, no answer was given in the article I read.....yes, absolutely a theoretical college question, but I thought it was interesting that the professor was teaching an undergraduate course that tries to get students to think about these things, and then about how to be prepared in areas where there are problems. And yes, there is a lot left out - maybe someone else can make a better problem for the mathematically inclined? Using a generic volcano?
@Lurking, Renato,tephra was defined for the problem as the total ejecta product, no distinction as to type..

And if I'm wrong, I'd like to Phone a Friend.

Erik, Boris, your numbers? :)

Awwww birdseyeUSA, you're the perfect example of how people here challenge our grey matter every day. Ok admittedly my matter has more rust spots than most, but I feel grateful that I'm able to participate.

My "in-depth research" (that lasted no more than 10 minutes once I saw a formula that involved sin) resulted in finding this paper about Dispersal and Total Mass of Tephra and Comparison with Plume Transport Models at:

http://www.raunvis.hi.is/~mtg/nemritg/BO-MS_2007.pdf

Of course I haven't read it ;) but it might be useful for others here. :)

@ Princes Frito - There, you see, works every time, what a great place - more reading matter. My pile (I print out everything,I'm a committed hard copy old fogey) of Ejya material is (I just bundled it) about 6" thick....now all I need is a blizzard and I'm all set.

Don't try this at home: volcano eruption demonstration and calculation of velocity, pressure, from vertical travel distance. You'll approve of the photographed efforts.

classes.colgate.edu/kharpp/Depth_Charge/default.htm

Pdf format, for the intrepid geology course instructor.
nagt.org/files/nagt/jge/abstracts/Harpp-1_v53n2p173.pdf

@birdseye - I can relate! If it isn't in print form sitting on my desk in front of me, I can't do the "read, recite, repeat" enough to get my head wrapped around it, let alone retain the info. I was a textbook junkie at an early age :-(

6" of print? You're hard core! :) Ok I'll start our session.

Hello, my name is Princess Frito and I'm a paper-and-ink addict when it comes to the earth sciences.

*heads off to the free donuts and coffee in the corner*

@Passerby - Cool! Thanks for sharing.

I approve of the photographic efforts, and will definitely not try that at home! :)

My name is parclair lost in the ether. I'm a print addict. although when traveling I succumb to the addiction of my pda reader. Help me, I've even downloaded the adobe pdf reader so I can read the yellowstone papers next month. *looks for chocolate and a cigarette*

There there, parclair. We're here for you. *gives parclair a Toblerone and a lit cigarette*. Put down your pda reader so you don't get it wet, because the first stop on your road to recovery is the Blue Lagoon! Guaranteed no Speedos or thongs, or your money back :)

http://eldgos.mila.is/english/lonid/

Or you could take a trip to the Twilight Zone, where you encounter a new and strange vision of the Earth's Core.

Melting-induced stratification above the Earthâs inner core due to convective translation. Nature 466, 744-747 (5 August 2010). Doi:10.1038/nature09257.

www.nature.com/nature/journal/v466/n7307/pdf/nature09257.pdf

See Fig 3 (yes, you can see it, 'Figures Only link', even if you can't read the whole paper). We have an oblate, asymmetric core that is more dense and hotter on the east side, and cooler, lighter and pushing up a bit, on the West side.

Then, I want you to think about this ocean floor gravity map:
www.ngdc.noaa.gov/mgg/image/global_topo_large.gif

Where oh where, do you think the West side of the core sites on this gravity map??

Hint, hint: dense iron 'pushes' strong gravity (geoid) features 'upward', like say...over Iceland. And its less, where the cooler iron is crystallizing out.

Damn me, but I think this might explain why the earths surface features are arranged in space, that look as they do. Why the Pacific Plate is a major dominating feature with its bright green subduction surface zones closer to the cooler, crystallizing and less dense side of the core.

Must think on this more. Not sure I have the geometry right, but it does seem to fit...
Off to bed.

You guys make me laugh. And I love it!

@Princess Frito

"..that lasted no more than 10 minutes once I saw a formula that involved sin.."

Is that opposite/hypotenuse or moral turpitude?

@passerby152 Good one - I'll pass it on to hazards prof.
Ref. stacks of paper, that's not including all the screen shots trapped in my computer - probably have at least one for every day after 14 April (haven't checked dates lately.) Requests?

Erik, you put up "The Eyjaf... Eruption and You" Aug 4 and here "we" continue to post on the 7th -- not just about our appreciation and what it is that draws us here, but about what is happening in the world geologically and cosmically (CME) speaking in relationship to Eyjaf....

That wonderful human passion we call curiosity is powerfully stimulated by your blog. And this is scientific curiosity, the truth no matter how it hurts or how ignorant our questions can make us feel. Your blog gives and receives in an unusual way. I am grateful for your gifts as a teacher of the next generation and as a conduit for current knowledge.

I returned to my life-long interest in the geological sciences (actually all the sciences, but there's only so much time in one day) because I wanted to find out the science re "Anthropogenic Global Warming". I felt almost certain about its scientific truth because I was a reader of Science and Nature. Needless to say, once I started researching the physics of CO2, the quality of both thermometer siting and raw-data "adjustments", the chaotic nature of Earth's climate, and feedback mechanisms, I was able to let open scientific discussion show me the evidence -- mostly the lack of the scientific method. More than anything else, I fear for the reputation of science.

Your blog has given me hope -- especially about the science that "young people" will learn from you and your colleagues. Your focus and reasonableness must inspire your community of readers from the novice to the most experienced because the science here is kept as "pure" as humanly possible and immensely interesting.

Thr other concern that drew me "back" to scientific research is the safety of human communities and that of my family. "The sky is falling" attitude that has become group think on the part of academics, politicians, media, and many scientists is very worrisome. I am grateful for the your reasonableness and that of those professionals who contribute here. For example, Boris Behncke, "I personally might seriously underestimate it [Katla]- but that's rather because I fear people get too fixed on one determined volcano when there are so many dangerous volcanoes on this planet. In my opinion, Katla is just one of many volcanoes that have a terrible potential." Because of my renewed interest in science, I can reasonably store food and other emergency items (see Leon @56) for future large eruptions or earthquakes (So California here).

This is only one thread with 159 posts at present and the breadth and depth of the comments and topics is, well, breath-taking. I deeply believe that the kind of science you promote here is the hope for the future. With gratitude.

Here is a great paper about the fracture zones and volcanoes of Iceland, it isn't too long and it's very very well written.

http://www.episodes.org/backissues/33igc/12-2new.pdf

Enjoy everyone,

AAAAAHHHHHHHHH......I'm still on my first cup of coffee, go to blue lagoon, beefy guys in speedos. aaahhhhhhhhh pda, can't see........

My first post got caught in review. Dave's Landslide Blog has extensive coverage of the British Columbia landslide. Like this blog, the comments are informative:

daveslandslideblog.blogspot.com/2010/08/landslide-at-meager-creek-british.html

@robert hurst 162, nice one, I like it, I like it - thanks! *adds more paper to copier* and parclair, NoCal (send recipes, please) thanks also for BC link. Ya just never know...

hi as this is all to do with volcanoes,so i thought i would liven up the blog a bit.
The Eyjafjallajokull-volcano song http:/www.youtube.com/watch?v=WlzJCuC9UE8
Fatal volcanic eruption
http://www.youtube.com/watch?v=8hO381ku1u4
This is a Pyoclastic flow
http://www.youtube.com/watch?v=WbkPo0Hws0M

#166 Thanks, @leon. The last is a very sad one.

Whoahhh....

A TV station picture gallery of it is located here:
www.ctvbc.ctv.ca/gallery/html/bc_mudslide_100806/photo_6.html

I linked to what appears to be the (or a) scarp face. This was not a small slide based on the amount of tree cover scoured off the valley walls.

Reporter Leah Hendry: "...it's made out of this kind of volcanic rock, almost like the kind of feeling of a pumice stone, so when the water ends up getting in there and ah it's been warm and the waters melting and it ends up breaking that rock right off, which is why they're concerned about the rain..."

Well, she's excited and on scene. At least she wasn't seen dragging a fallen limb into position set up a more exciting camera shot like Geraldo did here in Pensacola.

And just in case the TV station changes the content around (which many tend to do), here's that scarp photo squirreled away for safekeeping:

http://i34.tinypic.com/osh5yc.jpg

According to RUV news, there was an avalanche downslope Eyjafjallaökull. There's an image posted with the news showing huge blocks (of ice?). If anyone could take a look and explain what are those circular marks on all the blocks I would be glad to hear. :)
In Icelandic:
http://www.ruv.is/frett/aurskrida-vid-eyjafjallajokul

Hey Renato, those white things are cylindrical bails of hay wrapped in white plastic, the markings are probably the farms logo, I live in the country and they are all over the place.

#170 @Robert Hurst LOL! I was assuming they were huge ice blocks. Well, but there has been an avalanche, you can see the trail (but not as big as what I thought.) Thank you very much! :}
PS: I think they are called "cow-eggs" aren't they? Second time I take them for another object, since we don't get those down at the tropics.
Another lesson from Iceland...

I think that you're right about them being called "Crow Eggs", what's up with all of these avalanches today? The one in British Columbia was caused by the volcanic rock getting saturated with water and just letting go, I'm amazed at the size if it.

If you ever decide to get out of the tropics for a vacation and decide to check out Canada just let me know but unfortunately there are no volcanoes around Ottawa, lol.

#172 @Robert: Sad news indeed. But you don't need volcanic rocks to get mudslides as those. You might have heard about the recent deadly mudslides in Rio (January and April). Those were caused by human irresponsibility, both governmental and civil.
And yes, I would love to visit Ottawa (even better with no volcanoes around). Actually I should have gone there long ago, since I have a very good friend, (also "Robert") living there. Thanks a lot.

Hi guys,

If you haven't already, check out the amazing photos of the landslide and other areas around Pemberton, BC at this guy's photo albums. This has got to be the greatest collections of albums I've ever seen:

http://www.flickr.com/photos/dbsteers/

@Renato #169 - That was a mudslide (likely rain-saturated ash). The Icelandic word for avalanche (aka lavina) is 'snjóflóð' (lit. snow-flood).

#175 Thanks Reynir, NK. Google translator is to blame, but I didn't question assuming the hay bails were ice blocks.

mudslide on Eyjafjöll, one in British Colombia and a jökullhaup here in Norway, wich came from a glacier, that burst a wall of water.

I will put up a link :)

http://www.aftenposten.no/nyheter/iriks/article3759607.ece

http://www.tv2nyhetene.no/innenriks/vurderer-flomevakuering-i-luster-32…

here is the link about it , sorry that is not in English,.

but what NVE(norway water and energy)says its a rare phenomenon happen in norway a so called jökullaup, has occured and burst out from the glacier "Harbardsbreen"the cause of the burst is a sudden melting under the glacier and that the water pressure was so high that it could not be contained so it burst out and down the slopes.

This being the nostalgic [copy] Eyjafjallajökull [paste]topic, here is a Google Translate memento of Icelandic whale tongues http://i34.tinypic.com/16hivba.jpg

The web page photos has been revised. The former picture is pasted in and squared off at the LRH corner

(Google Xtr'd from www.ruv.is/frett/aurskrida-vid-eyjafjallajokul )

:D

Thor,Raving,thanks. Poor google trans, we must not be exercising it enough, it's forgotten everything it learned earlier.

hahaha google translate, has problems I recon?? haha

As I've been reading 'Eruptions' from the pre-Eyaf times it was mostly a great excitement to feel the heartbeats of the volcano-fanatic people here having the same pace. :-)
This blog was a very fresh information source about this certain eruption, it was like a long-long discussion show about the volcanoes in general. It was an experience watching the eruption of Eyaf through other people's eyes, to read their reactions on the events, to get info from local people, to cross fingers for the ones who had the possibility to travel to Iceland and personally smell Eyaf. The gratest of the experience here was to read the scientists' opinion, learn a lot from them, thanks to Erik and Boris Benchke.
If something happened this blog was the best place in the 'be the first to know' contest in media.
An last but not least I met a grat bunch of lovely people here. :-)

This is a timely thread! I've been persuaded to give a short talk on Eyjafjallajokull in November (not a massively scientific one, I hasten to add!). I'm not sure what exactly I'm going to be covering, but am going to carefully read all these posts for inspiration! I'll add my own thoughts too, once I've had a moment to think about it.

Erik, is your talk going to be recorded and put online anywhere? I'd love to see it.

Eyjaf:the Volcano that ate my Vacation. There's a children's book in that title, methinks. And I did make it to Belgium...but not until June. All my travel preparations had been prepaid with a no cancellations/no refunds clause. When my flight was cancelled, after long anticipation and a close watch on "Eruptions", I thought I stood to lose a bundle. But all of the companies refunded my money, and when I rebooked for the supposedly more expensive season in June...everything was cheaper. Let's make that Eyjaf: the Volcano that Partly Paid for my Vacation.
But best of all, in searching for reliable information as to what Eyjafjallajokull might reasonably be expected to do, (volcano psychology if you will,) I stumbled upon the "Eruptions" website, which cut through the chaff and provided up-to-the second data, rationally analyzed. The caliber of scholars and inquiring minds I found here outstripped any gathering of people I had ever run into anywhere, bar none. The grandeur and power of the visual images was soul shaking, and the guidance from those of you with a deeper understanding of the forces at work took me to a vantage point I could never have reached on my own. One day in future travels, I plan to hike up Eyjaf, and drink a cup to you all!

You really neaten it seem so smooth with your presentation but I conclude this topic to be rattling something which I guess I would never see. It seems too complicated and really clear for me. I am perception saucy for your close spot, I give try to get the fix of it!

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Great info. I will take a bit of time to think over this content!