Katla and volcanic weekend Riddles!

Today commenter Islander brought to my attention some news that the Icelandic volcano Katla seems to be picking up activity. But what is actually all the hoopla about really?

Katla is as most of you know one of the larger volcanoes on Iceland, but not the largest. The largest volcano on Iceland is the far less known Bárdarbunga volcano. Katla has been dormant since 1918, with the possible exceptions of small hydro magmatic events during 1955, 1999 and 2011. The hydro magmatic events are though not entirely proven to even have happened.

Katla has a 10 by 14km caldera that seems to have been formed during a minimum of two large VEI-6 eruptions. The volcano is covered by Myrdalsjökul glacier. During eruptions the volcano emits copious Jökulhlaups (water discharged as the volcano melts the glacier) and they are the single greatest threat from this volcano. Normally Katla has eruptions that range between VEI-3 to VEI-4, with larger eruptions happening after longer times of dormancy. Katla has had two large flood basalts after the ice age ended, the 5 500BC Hólmsá Fires and the Eldgjá eruption, both of them where following NW rifts trending roughly towards the larger volcano of Grimsvötn.

Earlier today (2012-09-29) the geologist Kristin Vogfjörð appeared on Icelandic Radio reporting that during the 24th of September a set of deep earthquakes had happened under Katla and that is considered as a sign of an increase of the risk for an eruption. She carefully avoided making any predictions.

So what happened then? Late on the 23rd 6 earthquakes ranging between 0 and 0.5M happened at depths ranging from 30 to 20 kilometers. On the 24th two more earthquakes occurred at 26 kilometers depth at the same location, those two where 0.4 and 0.7M respectively. The area is in the eastern part of the caldera.

Normally I have a deep respect for Icelandic geologists, but this is just so much hot air blowing. First of all the earthquakes are so minute that the amount of in-fluxed magma can comfortably be counted in wheelbarrows. It is like taking a piss in the ocean.

There was no associated tremor pointing towards magmatic movement of any significant scale. There is also absolutely no visible motion on the GPS stations surrounding Katla. Even at worst and these earthquakes where just precursors of a later influx we are still talking about years before an eruption taking place, and one should remember that Katla has had no less than two significant influxes of magma during the last 13 years without erupting. This so called “news” will only bring out the Katla fearmongerers, without anything having happened really.


Katla with trap formation in mid-ground. (behind the lake)

Image Copyright Eggert Norddahl

The weekend volcanic Riddles

GeoLurking posted a riddle yesterday. I am reposting it as the official volcanic riddle of the week so it will not get lost.

A Bald Hiker disappeared, the other ran away.

Who or what am I talking about? The answer should be one volcano, and one volcano-related name. Two points to be had.

Return of the Evil One’s Riddle

This time Alan has outdone himself to create a brain-wrecking geological riddle for us. I must admit that it is beyond my limited capacity.

Ek jou gesonde-of-tuin se gesig-gesentreerde kubieke “, maar my hoppers sou wees van geen nut in ‘n stope

What am I? What do I look like? What is the mining jargon? 3 points to be had.

Have a nice weekend everybody!


300 thoughts on “Katla and volcanic weekend Riddles!

  1. OT: just watched a Discovery Channel Dokumentation about british Airways Flight 009 K.L->Perth when they flew through volcanic ash. I guess the CEOs of todays airlines should ask Cpt Moody about His opinion regarding the threat of a ash cloud.

  2. The white or black smokers which release minerals into the sea not only release Common salt, Sodium Chloride but also many similar minerals found in association with fumarolic activity. One of these is Steropesite, Tl3BiCl6, a new thallium bismuth chloride, was found in an active high-temperature fumarole (~450°C) on the rim at La Fossa crater, Vulcano, Aeolian Islands, Sicily, Italy. The mineral occurs as tabular or stout lemon-yellow crystals up to 0.20 mm in length in association with bismuthinite and lafossaite.http://webmineral.com/data/Steropesite.shtml
    These other minerals are often removed in the refining process of sea salt production
    Rck salt mineral which which is mined near where I live, should correctly be called Halite. This link will show an image and all details of crystal structure and properties.

    • I mean this to be a more accurate answer to Alan’s riddle… But it’s early morning hours and I have been woken by arthritis pain so what better way to take my mind of it and wait for meds to kick in than to have a relax in the Volcano cafe and try to concentrate on things volcanic 😀 So apologies for rather muddled comments. The good thing about waking at night is that I have the pleasure of looking forward to that lovely snuggle down into a nice warm bed twice over before I have to get up and start the daily work. 😀

      • Being a biologist I felt I had to mention the use of sodium in regulatng cell metabolism in most living things. http://en.wikipedia.org/wiki/Na%2B/K%2B-ATPase
        So all of us here have a bit of magma making us work. We are all reliant reliant on Volcanic activity, ancient and modern for keeping us alive …..And I stated earlier that I couldn’t find a relationship between salt and volcanoes. How wrong I was !…. Here endeth my rumination for the night!!!!!

  3. The main effect of the pre-existing structures on collapse is their partial reactivation during the development of the outward dipping reverse faults … The reactivation forms a wider caldera along the direction perpendicular to the normal faults, resulting in an elliptical depression at surface. Its major axis is therefore parallel to the former extension direction. The reactivation may account for the formation of elliptic calderas, with eccentricity >0.8, elongated perpendicular to the rift axis. Moreover, this reactivation may suggest an explanation for the presence of subsidiary depressions around the borders of the calderas, influenced by both caldera collapse and regional tectonics (e.g., Spinks et al., 2005).

    Caldera Volcanism: Analysis, Modeling and Response 1st ed Gottsmann and Martí (2008)

      • Opportunism is the conscious policy and practice of taking selfish advantage of circumstances – with little regard for principles, or with what the consequences are for others.

        “Opportunistic?” How?

        • I suspect he meant serendipitous. 😉 Not a word one wants to use too often and I’ve now used it twice in one week.

        • LOL! I meant your comment was quite ‘timely’. Because we were talking about the Colombian earthquake and Sotará, which has calderas of this oval shape.
          I’m sorry!

          • There is nothing wrong with not being a native English speaker. They fare much better at it than I would in another language. I have only managed to achieve “functional illiteracy” in Spanish. (better than not speaking it at all).

          • I tried Schpanish at one restaurant in Naples; I figured near ’nuff… The waiter was extremely pixxed off, he clearly recognised Schpanish when he heard it, but this is what he said to me:
            “I speak Italian and English, DON’T COME to MY RESTAURANT and TALK SCHPANISH; now what would you like again???
            Once or twice in Napoli I overheard conversations that sounded very Spanish, At lunch, in a little pizzeria int’ Spanish Quarter: ” Pizza Marinara para compartir!” Click fingers; he seemed to get his own way pretty quick- smart boss…
            Mafia schpeak???
            That said; even functional illiteracy in Schpanish will come in pretty handy, it’s the second most widely spoken language in the world… After English; Chinese is schpoken by the greatest number of people, but Schpanish has a much wider geographical distribution…

  4. Ek jou gesonde-of-tuin se gesig-gesentreerde kubieke “, maar my hoppers sou wees van geen nut in ‘n stope

    not sure if I’m too far behind the times on this, not checked the earlier comments on my clunkputer.
    I saw someone translated this earlier and finally managed to get some time to comment on if.
    “healthy of the garden” – I presume that means “naturally ocurring”
    Face centred cubic – that seems like a straight translation
    maar my hoppers – looks like this is the point where it starts drifting into english mixed with afrikaans
    is maar – but or is it a volcanic maar
    are hoppers mining tools for sorting stuff , or just slang for my little kids or similar?
    nut in ‘n stope – sounds like nothing in the stope, “stopes and adits” , so perhaps he’d adit = had it ?

    Ok I’ll stop now in case it is all pointless and I’m just assuming alan levels of evil

      • The salt crystals are transparent and cubic and the colour can vary between white, clear, light blue, dark blue and pink.
        “In solid sodium chloride, each ion is surrounded by six ions of the opposite charge as expected on electrostatic grounds. The surrounding ions are located at the vertices of a regular octahedron. In the language of close-packing, the larger chloride ions are arranged in a cubic array whereas the smaller sodium ions fill all the cubic gaps (octahedral voids) between them. This same basic structure is found in many other compounds and is commonly known as the halite or rock-salt crystal structure. It can be represented as a face-centered cubic (fcc) lattice with a two-atom basis or as two interpenetrating face centered cubic lattices. The first atom is located at each lattice point, and the second atom is located half way between lattice points along the fcc unit cell edge.” From: http://en.wikipedia.org/wiki/Sodium_chloride

        Picture: http://www.highviewsaltsupplies.co.uk/salt-crystals.jpg

        If I understand the riddle text well, also a mining jargon for salt is asked.

      • Check out my ruminations at the following comment Diana Barnes says:
        October 1, 2012 at 03:13
        Wel it was one way of trying to get back to sleep 😀
        @ Lurking…….Hurrah for the sheep……and thank you Mr Farmers 😀 .

  5. Space Weather Message Code: ALTK07
    Serial Number: 86
    Issue Time: 2012 Oct 01 0305 UTC

    ALERT: Geomagnetic K-index of 7
    Threshold Reached: 2012 Oct 01 0300 UTC
    Synoptic Period: 0000-0300 UTC
    Active Warning: Yes
    NOAA Scale: G3 – Strong
    Potential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.
    Induced Currents – Power system voltage irregularities possible, false alarms may be triggered on some protection devices.
    Spacecraft – Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.
    Navigation – Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.
    Radio – HF (high frequency) radio may be intermittent.
    Aurora – Aurora may be seen as low as Pennsylvania to Iowa to Oregon.

  6. Is Calabozos in Chile another supervolcano? Just asking because it’s caldera is huge: 26 x 14 kilometers.

    • I love it when a thing comes together.

      “Taking place 0.3 mya, the second eruption was the most extensive. It was probably between 250 cubic kilometres (60 cu mi) and 300 cubic kilometres (72 cu mi) in volume and extended past the reaches of the caldera, down the adjacent foothills.”

      According to my little cobbled together formulaic model… the dimensions yield a 269 km³ estimate. The correlation coefficient is 0.8364 with an R² of 0.6995.

          • For comparison and control; this may be useful; erosion not explosion according to the literature:
            10km across, roundish and up to 1300 m deep
            Me n’ Lizzie had our lunch one day gazing down into it from Bejenado, the early arternoon clouds had started rushing in, so we hid behind a rock, it was 1200m to the bottom, but a tumble rather than a plunge, and plenty of pine trees to break yr fall… Lizzie suffers from Vertigo by Proxy, so her worst moment was when I stood up and took off my hoodie… 😀

  7. I find it interesting/disturbing that the Columbia Quake affected the Hekla Strain-meter in the way that it did… I think that something will happen there in the next few weeks. Just a guess though.

    BTW, It’s still sam. (With the yellow Gravatar.)

  8. I did not see this one coming…
    Last weeks little happiness area at the TFZ:

    South of this weeks happiness at the TFZ:

    And now the one in between:

    And now T the magick Lock:

    Seem like the entire microplate has been bending downwards at both edges and gone west with Hedinshöfn going a bit south just for good measure. The down part is new, the other motion was expected. What is not expected is that the middle part Flatöy did not budge.
    And the magick Lock is going nortwest and slightly upwards. Please note, this GPS is not ideally placed to measure inflation at T, the true number should be closer to the 3cm measured before since this GPS is place on the lava field, not the actual volcano where the chamber is.

    Strain, loads of strain. I only wonder if it will come in the form of a large earthquake or an uptick in inflation and more quakes in the actual volcano.

      • Gonna have to wait. Finishing up inventory, reloading the crap back into the truck and have two mid distance runs to do. At least all the server stuff is in one place now. Oddly enough, some of the part numbers that are specified don’t match what the manufacturer uses. Beats me. The part I don’t like about doing inventory, is that it never gets correctly implemented. What I specify just gets added to what I used to have. It’s like some perverse Archimedean spiral.

        • Welcome to my work day… It starts with me going:
          “Hm, how on earth come that we have 1400 barrels of whatnots?”
          “Don’t worry your shaggy head, it is an accounting thing…”
          “But it ads to the company balance?”
          “But we do not have 1400 barrels of whatnots! This can’t be legal?”
          “It is IFRS, we have to do the accounting this way… Stay out of the accounting in the future.”
          “But I am the CEO!”

          About then I feel a strong urge for beating something up and go home… I guess that the economics gnomes go berzerk on prune juice after I have left. Accounting, especially IFRS accounting takes place in a separate universe governed by laws that has no resemblence to logic, math, nor the laws of physics.

          Also, me:
          “Cool, we made a million today!”
          “It is horrible, all the solidity in the company is gone now!”

          If anyone can explain the last one for me…

          • All very confusing…too much money seems a non sequitur in everyday life. Or does too much cash attract unwelcome predators?

          • Cash is not how the net worth of a company is really counted. It is in company value, and that is mainly produced by bying things.
            Let us say that I spend 1 million $ on a continous miner (machine), that one will be written off in 5 years. Problem is that the machine is going to keep on working for 20 years. Problem one, every year your company value diminishes with 200 000 $ for five years. After that you are owning a “worthless” machine that will make you money since you are not spending them on a new machine. That money you think are profit is actually not creating any net value.
            As a CEO I keep track of the amount of cash we have so we can pay bills. That cash will in a well run company keep on growing. Normal people would call that profit. Accountants don’t. So once a year I have to scream at them that they are nuts and that if they do not fix it I will fire them. Around that time they finally get the message, do something strange called “goodwill” and lo and behold the amount of surplus cash goes from destabilizing solidity into being real profit. Only problem, goodwill is also written off in 5 years…

            Acounting is a universe of its own, governed by fraggly gobblin rules from the gnomes with the ledgers.

          • And I’m still stuck in a mindset that tells me to buy a 5-year old mining machine for peanuts and make profits for as little upfront capital as possible. But I can see that wont do much for mining machine manufacturers. So I guess accounting rules must follow some logic that has a sort of social aim , a symbiosis of businesses. ‘One for all and all for one’.

  9. Meanwhile back on El Hierro, there is more inflation:

    (Sorry if this has been posted already, but this is a flying visit)

    • Now this is my sort of Physics lesson. I almost can get my head round it…..until I stop and try to think beyond expanding universe…then I get all confused again!!

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