The Case for An Imminent, Catastrophic Eruption at Volcano Katla, Iceland

It may come as no surprise to ATS that there is a looming giant very close to Eyja- the volcano that recently erupted in Iceland- and which caused considerable disruption of air traffic all over Europe. The name of this volcano is Katla in English, and Mýrdalsjökull in Icelandic.

The caldera of the volcano has a diameter of 10 km (6 mi) and is covered with 200-700 metres (660-2,300 ft) of ice. The volcano normally erupts every 40–80 years. The flood discharge at the peak of an eruption in 1755 has been estimated at 200,000–400,000 m³/s (7.1-14.1 million cu ft/sec), comparable to the combined average discharge of the Amazon, Mississippi, Nile, and Yangtze rivers (about 266,000 m³/s (9.4 million cu ft/sec)).

en.wikipedia.org...

Normally one would not necessarily associate a huge flood discharge of water with a volcano, but in this case, it is covered with a massive layer of ice- which when melted due to the heat from rising magma, would do just that- melt a large portion of the ice, causing extreme flooding.

Katla has been showing signs of unrest since 1999, and geologists have concerns that it might erupt in the near future.[9] Particularly, monitoring has been intensified following the March 2010 eruptions of a smaller neighbouring volcano - Guðnasteinn - beneath the Eyjafjallajökull glacier.[10] The eruption of this nearby long-dormant volcano in March and April 2010 prompted fears among some geophysicists that it might trigger an eruption at the larger and more dangerous Katla.[11][12][13] In the past 1,000 years, all three known eruptions of Eyjafjallajökull have triggered subsequent Katla eruptions.[14] Following the 2010 Eyjafjallajökull eruptions, on 20 April 2010 Icelandic President Ólafur Grímsson said "the time for Katla to erupt is coming close ... we [Iceland] have prepared ... it is high time for European governments and airline authorities all over Europe and the world to start planning for the eventual Katla eruption".[15]

Considering the gravity of this, many of us have been watching this volcano with piqued interest, and studying these "signs of unrest." As an avid quake watcher here at ATS, I am no exception, and over the years have become somewhat of a skeptic when it comes to overhyped claims in the seismic world.

In the case of Katla, however, recently there have been some eye-opening events that may merit further vigilance of the utmost concern.

First, in the last few days, there have been many earthquakes of a size, depth and location that are concerning:



en.vedur.is...

These quakes are occurring on what may well be a magma conduit between the two volcanoes. Their location and depth suggest potential magma intrusion into Katla's chambers below. And one of the first questions that will arise amongst the volcano watching public is whether there have been any harmonic tremors detected. But in Katla's case, that can be a very difficult question to answer.

Given that Katla is covered with a massive layer of ice, it should be noted that ice in itself, depending on its temperature, can seriously attenuate (dampen) seismic waves. Several studies have been done on this, proving that it's true. In Katla's case, given its location, the temperature of the ice can be surmised to translate into moderate to high attenuation rates of seismic waves. More reading on this for the technically inclined.

And this presents a particularly tough problem for seismologists trying to scan and identify harmonic tremors at Katla- known precursors to volcanic eruptions. These tremors can vary in amplitude considerably. And the point is that if they are of a lower amplitude, the attenuation factor of the ice itself may well conceal them from scientists. And that, of course, is not good. NOT GOOD AT ALL. It means that an eruption at Katla could well come at any moment, with little or no warning- even with the best of technological capabilities.

Fortunately, harmonic tremors are not the only indication of imminent eruptions. I say fortunately, but in a minute we might have to reconsider that word.

GPS measurements of ground deformation, and in particularly, uplift, are also used to gauge eruption potential. And so what might GPS measurements look like at Katla recently? Well, take a look:



hraun.vedur.is...

Since 1999, that is considerable uplift at a station positioned right on the volcano itself. Note that is the up/down axis. The other axes are here, but they don't matter as much:

hraun.vedur.is...

Uplift, especially near a volcano, can be an indicator of magma intrusion.

The Icelandic Met Office also publishes another continually running chart called "tremor," which appears to be simply a non-quantified gauge of seismic activity across the more volcano-pertinent eathquake frequency ranges of 0 to 4 Hz (in this case). And so here is the recent graph at station God, again, right on top of the volcano:



You can keep an eye on this here, as it updates once in a while:
hraun.vedur.is...

Now to me this is particularly troubling in that harmonic tremor tends to occur in the 2 to 4 Hz region, which as you can see, is the light blue. So are these harmonic tremors? Possibly. But whether they are or not, one thing is clear: most indicators are showing signs (to me) of an impending eruption.

Finally, it should be noted that as amateur quake watchers, we are somewhat limited in the tools at our disposal to help determine these things. But one thing we do have is a program called GEE, which let's us view the outputs of many seismic stations in near real time. And with this program, I have been watching the only station available in Iceland to us, station II.BORG- for quite some time.

And that's another whole subject, but suffice it to say that I am suspicious as to why, with so many stations across several networks, spread out all over Iceland, and particularly, stations monitoring all their volcanoes- why we are only granted access in GEE to one single station, II.BORG. A station which is over 100 miles away from any of the real action at Katla or the others. Basically, it is useless for any kind of harmonic tremor detection at Katla or the others- because it is so far away!

But even so, I really have to question why the background "noise" levels at station BORG are so darn high. Here is a screenshot I took in GEE of these levels:



Those are averaging 8 to 12 microns/per second, which is abnormally high compared to any number of other stations I watch on a regular basis. It STAYS there, and sometimes goes even higher. It's as if that whole country is constantly shaking. Is that an indicator of the voluminous seismicity from 100 miles away at Katla? I damn sure hope not, or we're in trouble!

It may be best to refer to the authorities, although at this point, with politics and deception what they are in the world today, I can't say I totally agree with that statement anymore. And currently, the authorities are not saying much regarding Katla.

That's not to say that we haven't been warned by them about Katla though. Recently the President of Iceland issued a warning about Katla, surmised in this excellent video on the subject, which I highly recommend watching:



In conclusion, I am a bit concerned about this volcano, and the potential consequences of a large eruption there. But I guess when all else fails, we can keep an eye on the webcam, which is constantly pointed directly at it:

www.ruv.is...

Know where thy "print screen" button is, just in case...

It definitely looks like something is going on, with all the seismic activity located on the one side of the volcano it looks like magma is on the move. Time will tell but in my opinion something is going to blow.

Uh oh, and now another quake has just occurred, this time in a new location, near the dome crater:

en.vedur.is...

Is this showing signs now that the crater is giving way?

reply to post by TrueAmerican


There certainly must be something large looming in Iceland. At first I was impressed with Iceland with the coverage of Elysckfgoxaxzy's eruption. Now, trying to get up to date information is slim. The Tremor maps are outdated and/or do not give access at all to them - same for the seismo's. There is a swarm ongoing at Bardarbunga - but it doesn't show on Their map? Why? I do agree with you that things are heating up!

reply to post by TrueAmerican


Hey Buddy...thanks for the heads up on Katla....I live in Finland and the I remember real well what happened earlier this year when Eyjafjallajökull erupted....I honestly hope that the worse will be only air travel disruption....Or do you think that this thing has serious potential to blanket our planet into ash thus sending us into a mini ice age? Anyways...
Thanks for sharing!

Regards,

ringht_n_wrong

the yellowstone caldera is steady rumbling..
hold on to your hats everybody - and please-
give your volcanoes names we call pronounce?
katla is perfect..whittle those other ones down.eh?
If - the bp sabotage has broke the gulf current-
and katla goes off- shudder to think.
a long cold lonely winter.

Originally posted by Anmarie96
There is a swarm ongoing at Bardarbunga - but it doesn't show on Their map?

Well, it might depend on what map you're looking at. Try this one, because it does show that swarm:

en.vedur.is...

And just today, there was a small quake right underneath the peak of it...

It's as if that whole country is constantly shaking

@TrueAmerican. Maybe it is! After all it is sat on a mantle plume larger than Yellowstone if you believe the tomography at either place.

[atsimg]http://files.abovetopsecret.com/images/member/137eefaa9620.jpg[/atsimg]

So let us take a look at the whole period since April 13th on the tremor graphs.



Mm, sort of puts that small time slice in it's place I think despite the fact that it is a little out of date.

This one is not out of date

Now, first the SIL stations relative to Katla.

[atsimg]http://files.abovetopsecret.com/images/member/37faad5c8e0a.png[/atsimg]

And then the GPS stations



Now as it happens the GPS stations and SIL stations are in the same place so for the ones shown in the composite VMEY is irrelevant as it is on Vestmannaeyjar, and of the rest not one of them is actually on top as Katla whereas you said

Since 1999, that is considerable uplift at a station positioned right on the volcano itself. Note that is the up/down axis. The other axes are here, but they don't matter as much:

The uplift over the past 2 years for example is a max of 50mm or 2 inches. Have you taken in to account the fact that there is isostatic rebound due to... whatever ...climate change shall we say which is going on here as well? Have you also taken in to account that these measurements are relative to REYK and assume that REYK is static. But do you know whether it is? If REYK was going up these figures would be worse and if it was going down they would be irrelevant. REYK is of course on the other plate, the western side if Iceland and the two plates are moving apart at between 19 and 21mm per year.

Glaciers in Iceland began retreating around 1890, and since then the Vatnajokull ice cap has lost over 400 km3 of ice. The associated unloading of the crust induces a glacio-isostatic response. From 1996 to 2004 a GPS network was measured around the southern edge of Vatnajokull. These measurements, together with more extended time series at several other GPS sites, indicate vertical velocities around the ice cap ranging from 9 to 25 mm/yr

This is extracted from Glacio-isostatic deformation around the Vatnajokull ice cap, Iceland, induced by recent climate warming: GPS observations and finite element modelling

The figure of 25mm accounts almost entirely for the uplift you see over the past 2 years. I have a similar study somewhere for Katla but I can't find it just at present. The findings are the same.

Consider also that small co eruptive displacements are observed at SOHO and HVOL due to an eruption that started on 26 February 2000 at Hekla, located approximately 45 km NW of the stations, in other words eruptions affect the readings.

There is a swarm ongoing at Bardarbunga - but it doesn't show on Their map? Why?

@AnneMarie

Basically because their maps only shows the past 48 hours and it has stopped being a swarm if it ever was one. I have the maps downloaded once and hour every hour that my computer is on so that is normally 14 maps a day if any one wants them let me know. I gave up uploading them as no showed any interest. I have these going right back to April.

I also have all the tremor graphs for Myrdalsjokull, which is the glacier by the way. The volcano in Icelandic is Kotla. In exactly the same manner the volcano Eyjafjallajokull actually is the name of the ice cap or glacier, jokull being ice cap. Eyjafjoll is the volcano and the work fjoll is the direct equivalent of fell or mountain in English. I have both the full and 10 minute version. Most of them I have whittled down to two a day but I see them all and rest assured nothing is going on at present.

All in all I personally don't feel there is much to be worrying about at present. Incidentally the Eyja/Katla connection is a fact however to some degree the connection as far as Katla going after Eyja is anecdotal since Katla erupts far more often that Eyja and therefore there is a good chance of this occurring.

Originally posted by PuterMan

It's as if that whole country is constantly shaking

@TrueAmerican. Maybe it is! After all it is sat on a mantle plume larger than Yellowstone if you believe the tomography at either place.

[atsimg]http://files.abovetopsecret.com/images/member/137eefaa9620.jpg[/atsimg]

And so you are suggesting that's the reason these background levels are so high at BORG? I would assume that's what you mean... The question is, if they are that high, that far away, what in the heck do they look like at Katla???

Still, interesting point. Tell me, do YOU believe the (seismic) tomography? If I remember from another post on another thread you stated that me giving them a 50 % accuracy rating with their tomography was "generous." So where does that leave us?

Mm, sort of puts that small time slice in it's place I think despite the fact that it is a little out of date.

Yeah, a whole month out of date...You have any recent info? Everything here in this thread is as of today.

This one is not out of date

Yeah, but that's Eyja, I am concentrating on Katla.

As to your points on the GPS readings, I will concede that could be due to your reasons. So point noted, thanks.

And so now I have another question...What about gas emissions? I cannot find anything on that for Katla, and I don't see anything at the Iceland Met Office referring to them...

All in all I personally don't feel there is much to be worrying about at present.

If we can't even trust the tomography to any reasonable degree, I'm not sure how you can say this. We've got quakes on the volcano. And as far as uplift, maybe you ought to take a look at that video in the OP. The subsidence (depressions) in the ice can actually be because the heat underneath is melting the ice cap. How can they even be sure that there ISN'T uplift of the actual dome underneath 600 to 2000 feet of ice?

Incidentally the Eyja/Katla connection is a fact however to some degree the connection as far as Katla going after Eyja is anecdotal since Katla erupts far more often that Eyja and therefore there is a good chance of this occurring.

Oh? I though they erupted roughly in the same amount, and back to back? Hmm, got any info on that?

Originally posted by TrueAmerican

And so you are suggesting that's the reason these background levels are so high at BORG? I would assume that's what you mean...

No that was sort of tongue in cheek! BORG did have some data problems, maybe they are still there? Take a look at BORG. It is bracket by roads and right by a river. Maybe the high levels are as a result of the river?

Tell me, do YOU believe the (seismic) tomography?

No I don't think I do. I have been trying to get my head round this hot spot thing and they seem to say anything they think fits and yet most of it does not.

Yeah, a whole month out of date...You have any recent info? Everything here in this thread is as of today.

But the point is that the levels where MUCH higher during the earlier eruption so that fact that the last data is actually 12th September (not a month) is not actually that significant unless the whole thing had erupted again, which it has not.

Yeah, but that's Eyja, I am concentrating on Katla.

True

And so now I have another question...What about gas emissions? I cannot find anything on that for Katla, and I don't see anything at the Iceland Met Office referring to them...

Unfortunately we get used to the flood of information that is available from USGS. Most of these organisations do not publish their data so we are lucky to get what we do get, frustrating though it may be at times.

We've got quakes on the volcano. And as far as uplift, maybe you ought to take a look at that video in the OP. The subsidence (depressions) in the ice can actually be because the heat underneath is melting the ice cap. How can they even be sure that there ISN'T uplift of the actual dome underneath 600 to 2000 feet of ice?

There are always quakes on the volcano and particularly during the start of the summer and the end of the summer during the ice cap melt and refreeze. This again is in the study I can't lay my hands on - but I will find it.

Oh? I though they erupted roughly in the same amount, and back to back? Hmm, got any info on that?

Katla
1955, 1918, 1860, 1823, 1755, 1721, 1660, 1625, 1612, 1580, ~1500, 1416, ~1357, 1262, 1245, ~1179, ~934, 920

Eyja
2010, 1821/3,1612,920,550

I just don't see how if Katla is erupting so much more frequently one can say that because Eyja went Katla will go. Yes at face value it does appear to be so but Katla erupts every 40 to 80 years so the chances of it hitting the same date are good, and earlier records are a bit haphazard to say the least. After all they say Eyja erupts every 200 years, but that is not the case if these date are right. I have no doubt that Katla will go any maybe within a couple of years, but then it is due to do that anyway regardless of Eyja. By the way Katla has a magma chamber of about 21 cu km if you are interested. That is a VEI 5 if my memory serves me right.

Katla dates source
Eyja dates source




Adding this which is the link to Smithsonian for the Katla eruptions

As you will see some of the earlier ones are not from historical records, neither are they for Eyja so the date are probably not pin point accurate.

Originally posted by PuterMan
By the way Katla has a magma chamber of about 21 cu km if you are interested. That is a VEI 5 if my memory serves me right.

But that's of course if we go by their tomography.

By the way, pretty good quake just hit Chile/Argentina in GEE....Coming right up at USGS...

5.8

earthquake.usgs.gov...

Originally posted by PuterMan
By the way Katla has a magma chamber of about 21 cu km if you are interested. That is a VEI 5 if my memory serves me right.

I just checked Wiki, it's a VEI 6.

What sort of damages will occur when this thing goes? How long will the ash persist? Effects of the flooding?
All I can find are vague "Will be much worse..." statements after an internet search. And something about how it could reverse the affects of greenhouse gasses. (Not that old chestnut again...)

Originally posted by Tarrok
I just checked Wiki, it's a VEI 6.

Actually, it may be as little as hardly anything, or as big as a VEI 8. There is just no way of knowing until it happens. If you have read this thread and other places, as you can see some of us do not take their word on seismic tomography- because frankly there are so many variables that go into it- that's it's erroneous in nature.

Therefore the actual volumes of magma in any given volcano, especially one under 2000 feet of ice, are really unknown. Yeah, they might have an idea of the size, but it's just an estimate. And those estimates are easily challenged. But given the size of the crater, past eruptions, and other things- Katla is no doubt a menace.

What sort of damages will occur when this thing goes? How long will the ash persist? Effects of the flooding?

Again, totally depends on the size of the eruption. Locally, people seem relatively prepared. For one thing, they have avoided population centers around the immediate vicinity of Katla, so there are few people who would die there from the immediate effects, unless the eruption was so big the pyroclastic flows and debris reached beyond the radius expected.

2 more quakes have just hit the Katla/Eyja conduit (in red):



And a third hit near the crater edge (in blue).

So PuterMan, would you say these are occurring in the typical locations that indicate that they are part of this summer/winter "refreeze" you mention? Or are they occurring in new locations?

I'd really like to see info on that. In a general sense, Thanks. Thanks for just being you and being here at ATS to converse with.

Speaking of members, where in the heck is Shirakawa? Hadn't seen in months!

reply to post by TrueAmerican


Yes, I know the whole map and I know it is for 48 hours. Please. My point being if you to the Tremor map Here, the only plot, map, etc. you can get on the Vatnajökull glacier is Grimsfjall, which is south east of Bardarbunga. In addition, there is no instrument on Katla that they are sharing the information. But at least that has a web cam. As for Shirakawa - idk - maybe They put a lock on him or hired him?

Originally posted by Anmarie96
In addition, there is no instrument on Katla that they are sharing the information.

Yes, there is: Godabunga

It is provided in the OP. It's just that for some reason, the link for it from the map you linked to is not working.

Here:

hraun.vedur.is...

gotten from here:

hraun.vedur.is...

Which is in turn, gotten from the very map you linked to. It says:

From here you can view tremor plots from all our seismic stations.

reply to post by TrueAmerican


Umm - Godabunga is off to the northwest side of Katla in between Eyjaxyz and Katla. This area IMO has been shaking much more than is usual and while the season is changing and the ice (dreaded ice) is going through changes, I think there is more to it than that. LOL love the way it's always the fault of the Ice

Originally posted by Anmarie96
Umm - Godabunga is off to the northwest side of Katla in between Eyjaxyz and Katla. This area IMO has been shaking much more than is usual and while the season is changing and the ice (dreaded ice) is going through changes, I think there is more to it than that. LOL love the way it's always the fault of the Ice

Yep. And another quake just occurred in that area too, a few minutes ago.

Yes I know where Godabunga is. But at the moment, it's all we've got. Actually, if you want to get technical about it, Katla is covered with stations I have discovered in GEE. But we have no access. Here is a little map zoom in of Katla from networks in GEE:



But they're in gray- no access. It's one of things I am bitching about in the OP. They are there, but no go.

Well PuterMan, I think we might want to reconsider your comments about the potential reasons for the apparent uplift at Katla.

According to this abstract for an article in the Journal of Volcanology and Geothermal Research:

The Katla volcano is covered by the Mýrdalsjökull ice cap and is currently one of the most active volcanoes in Iceland. It has erupted twenty times the past 1,100 years. The neighbouring volcano Eyjafjallajökull has erupted twice, simultaneously with Katla. As glaciers cover both volcanoes, their eruptions are phreato-magmatic by nature. The volcanoes are located directly south of where surface expressions of the rift cease. Seismically, Katla is one of the most active volcanoes in Iceland, showing an annual cycle in activity, observed from at least 1960 and less pronounced since 2004. From 1999 to late 2004, GPS measurements revealed steady inflation of the volcano, showing uplift and outward horizontal displacement....

[url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B7W57-4X83J77-7&_user=10&_origUdi=B6VCS-4J3WS9F-2&_fmt=high&_coverDate=12%2F31%2F2010&_r doc=1&_orig=article&_origin=article&_zone=related_art&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=cc6df3862c9db9b7f96c5236c996320d]LINK[/ url]

So clearly there WAS uplift to 2004....The question is now, is there still? And further, since there was uplift, then all that magma has still found no release. And why if there WAS uplift, should we assume that it has stopped? If anything, we should assume that it has continued- even if at a lesser pace.

Bah, the link won't display properly no matter what I try...copy the link portion and paste

PuterMan also, some new info (to me) on your comments about the quakes being seasonal:

The earthquakes under Goðabunga show a clear seasonal correlation with a distinct activity during the autumn. This pattern changed in 2002 to more continuous activity. The earthquakes in the caldera have a swarm character, and the largest earthquakes occur there.

Again this is from another scientific document here. Page 13.

So did this change to more continual activity change again back to seasonal only in recent years? Or does this still apply?

Note part of the conclusion in that document:

In recent years Katla and Grı´msvo¨ tn have shown the highest inflation rates with ca. 3 cm/a. and tilt data from Hekla suggest that magma accumulation is taking place. At Katla, continued uplift coincides with elevated seismicity. If uplift and internal pressure build-up continues at these volcanoes, eruptive activity is a likely consequence within several years.

Considering that paper was put out in 2006, within several years means right about now, or last year really. Sounds to me like we're already overdue for Katla to erupt.