Sheepy Dalek – Name that Lava VIII

Lava of the Week!

Last week got a bit confused due to the mix-up of the two pictures. This time I have made triple sure that the picture shows the same as the answer.

The Score is:
3 Diana Barnes
2 Talla
2 Ursula
2 Doug Merson
2 Hattie
1 Schteve
1 Jim
1 Luisport
1 Heather B
1 Birgit
1 Jamie
1 Henrilerevenant
1 UKViggen

This week’s competition

I will award one point for the correct name of the volcanic system, one for the volcano, one point for the eruptive vent, and the final point for the lavas (minimum two correct lava types).

This week I want the name of the volcanic field, the volcanic formation on the picture, and of course the lava. So 3 points to go for.

Call for post-texts

I am soon going to become pretty occupied since I will be preparing to move, and also with work. So, if you have a good idea for a blog post, please do not be shy. Who know, you might become the next Alan.



443 thoughts on “Sheepy Dalek – Name that Lava VIII

      • But he missed the mark.

        He is very quick to assign blame to ‘evil’ capitalism. The sensationalism and distraction method has been used since the Roman Empire to keep the populace preoccupied.

        That is the hallmark of government. In Rome, most of the funding was done by the wealthy families, they benifited from not having turmoil in the streets. Its hard to sell a product with a pissed off populace.

        Today is no different.

        • Difference is that Adorno describes quite succinctly how the media is used to pacify the population. Just look at Italy under Berlusconi, US, UK with the Daily Fail et Ilk, and so on and so forth.
          The Romans did the same, they didn’t have TV, so instead they had The Games complete with Christians thrown to lions and people beating each other to death. Seemed to work in making the populace forget that life was shit. Same shit, different media.

        • Ok, I majored in philosophy and my German is pretty good if I say so myself… that’s how I earn my living after all, translating the glorious beast into crude English… and I am pretty good at reading German philosophers in German, even getting a grip on Husserl, which is saying something… but Adorno had me stumped. If I could read ancient Greek I might have had a chance.
          That said, the bit I understood, I liked.

    • Erm…,

      Don’t you find their selection rather limited (and not in the sense of limited edition)? Don’t you find people like Sir Karl Popper, Thomas Kuhn and Ayn Rand conspicuous by their absence? 😛

  1. And now i am entering the full force dragon mom stage which i am in real life too and will rant on.
    HRH Princess Fritto graced us with her presence here, even Dr. Boris stopped by, ( Thank you to both of them) Renato and Henri found us after a while. I wish Motsfo and MRK and many others would drop by here too, and talk with us. conversations are impossible on Eruptions presently but here they are welcome. Erik is a supercool expert and his posts rule, and i understand he wants to post them in a scientific surrounding where other experts are, but unfortunately for us, this site uses a system for commenting which is very user-unfriendly.

      • Well, could someone who is still able to post on Eruptions please invite them again, I am not, or i would do it myself. I am not trying to steal Eriks readers, thats impossible anyway because he is a real expert and, i think, a good professor. But maybe people could chat here and get scientifically educated over at Eruptions.

        I am simply not willing to be forced to join sites like Facebook or get myself a Google account in order to be allowed to say something, (which i often refrain from anyway because i am not expert and my view of things is not important or enlightening.
        And what i hate too….. whenever i klick a link and want to go back again, comments get sorted by most popular again and i can sort them by newest first again and try to find where i left off. And i cannot view more than 80 comments, ok so sort them by newest first and then by oldest first so to read them all, but if there are over 160 comments, which rarely happened lately, i cannot read them all.
        This sucks.
        Rant off.

  2. in saying this, I know I repeating myself, but the harmonic tremor charts for Gomera, seem to be a lot more real, making sense of bobette’s activities, being a woman she will know how to make an entrance, when ready

  3. I’ve been wondering, I am still wondering about this, which I’m sure, someone brought it up in this café: Looking at the tremor charts of the Canarian Islands there is no trace at all of the recent 8.6 North Sumatra earthquake:
    As you see: nothing at all. Now compare that to the 11th of March 2011 (I took another station than Hierro/CHIE as it looks messed up:

    Click around to the other stations and compare.
    Can anyone explain this huge difference in what the seismographs pick up?

  4. Is this one interesting ?
    mb 4.6 Region NORTH OF SVALBARD Date time 2012-04-29 11:29:56.8 UTC
    Location 84.21 N ; 5.64 W Depth 60 km
    2831 km NW Stockholm (pop 1,253,309 ; local time 13:29:56.8 2012-04-29)
    1879 km NW Murmansk (pop 319,263 ; local time 15:29:56.8 2012-04-29)
    1690 km NW Alta (pop 12,077 ; local time 13:29:56.8 2012-04-29)

  5. Quake in São Miguel, Azores… Magnitude ML 3.1
    Date time 2012-04-29 11:15:48.0 UTC
    Location 37.75 N ; 25.33 W
    Depth 1 km
    Distances 1662 km W Casablanca (pop 3,144,909 ; local time 11:15:48.0 2012-04-29)
    9 km NE Vila franca do campo (pop 5,035 ; local time 11:15:48.0 2012-04-29)
    30 km E Ponta delgada (pop 20,056 ; local time 11:15:48.0 2012-04-29)
    1328 km NW San cristóbal de la laguna (pop 139,928 ; local time 12:15:48.0 2012-04-29)

  6. Photo courtesy of Julio Vivero posted on the Avcan Facebook pageof the gulls feeding on the dead fish over the vent yesterday.

    • Anyone know if the seagulls are OK after eating these dead fish? Has Bob just pre-cooked the fish or are the fish toxic?

      • Gulls eat all kind of rubbish from landfill sites that must have noxious gasses in them – don’t know what volcanic gas would do to them. Diana Barnes might know. 🙂

        • Julio Del Castillo Vivero comment on AVCAN facebook: (roughly translated by me),,
          “Its not that they (the fish) were floating on the surface, there were a few, not that many and were some 10 cms more or less, but they were surfacing bit by bit and later the gulls were fighting over them. I don´t remember why they died, but it could be the CO2, or lack of oxygen, but anyway, the ULPGC took various samples of the volcano and surley could give an explanation in a few days.”

  7. Monitor micro seismic activity increased in Nicaraguan volcano

    Managua, Apr 29 (Prensa Latina) Nicaraguan Experts reported more seismic activity at Masaya volcano, about 20 kilometers south of Baghdad, an increase in expulsions of sulfur gases, which survives today in disaster warning system. According to the report , a crack in the main crater leading to higher emissions and sound like a jet engine. Specialists of the National System for Prevention, Mitigation and Attention to Disasters (SINAPRED) and the Nicaraguan Institute of Territorial Studies (Ineter), explained to the press that several days ago detected the unusual behavior, but for now there is no reason for alarm. The director of the Ineter Goefísica, Angelica Munoz, told the publication on 19 Digital monitor the situation closely because of Masaya rising emissions and temperature above the normal range. assess technical Teams seismic tremor, but said any type of emergency and the gates of Masaya Volcano National Park remain open to the public, said director Ineter, Jorge Castro, and SINAPRED executive secretary, Guillermo Gonzalez. We are in constant communication with both the mayor and members of the Departmental and Municipal Committee, so this is just activate the permanent information and be ready for any eventuality, said Gonzalez . The Masaya is one of six active volcanoes in the country, with a history of about 18 activities from 1520 to date and major incidents between 1772 and 1820, recalled the student. The soil at the site is mostly covered with poor vegetation lavas, for coatings in the last thousand years, although only two rivulets of lava have fallen since the sixteenth century. rmh / mjm

    • Piter, perhaps you might know – I read some time ago that someone from the USGS considered that Long Valley had shot its bolt as a caldera and the only volcanism likely in the future was minor? Do you recall this?

      • Yes, unles something odd happens it would not be able to go beyond VEI-5 due to not being primed for a caldera event.

        • Heya Carl, do you have the research Henri is referring to somewhere? Or do you recall the reasons for LV ‘not being primed for a caldera event’. I recall it was concluded after something of a chemical analysis but I’m not sure.

          • I thought it was deduced from the size of the area that inflated in the 80s.
            If I remember correctly they did a calculation of the size of the chamber then. And that size was to small for a proper caldera formation being possible.
            Sadly I do not have the study any longer.

      • I do recall a chemical analysis of fumaroles (?) indicating the same, but that’s a rather wild guess to me. The Bishop Tuff was produced some 760.000 years ago, thats more than enough time to refill a magma chamber significantly. I’m not sure what the future holds. Chances for another cataclysmic eruption like the Bishop Tuff is not likely, but even small to moderate activity would be interesting. It’s a very lively, active caldera and well worth watching mainly out of geological interest, not necessarily because of it’s potential danger.

      • Wrong plot… this is the correct one.

        (the previous one was an intermediate “calculate the bounds” plot.)

    • Okay, going over that data, and the quake list. Making a few assumptions, I come up with a fill rate of about 19,289 m³/day.

      This is based off of the movement of three GPS stations and an assumed chamber depth of 5.76786 km. The largest error in this is the placement of the center of the chamber, and could be off depending on the dynamics of it. (are the quakes on the upper periphery?)

      The three station GPS offset fits a chamber radius of 0.116 km.

      Unless someone wants more detail, that’s as far as I’m going. Took half an afternoon to revamp this and extract the data.

      • If we make the further assumptions that your placement of the chamber is correct, thus your calculations are spot on, this is the only activity going on and that it’s not a continous process but a temporally limited intrusion, then the current activity is minor, correct?

        • Very minor, but can be what tips the ball in the end. And also, we should remember that it seems to have been going for at least 6 motnhs.

  8. There has been another quake near the MAR.

    mb 4.4 Region NORTH OF SVALBARD Date time 2012-04-29 16:29:58.4 UTC
    Location 84.37 N ; 3.36 W Depth 40 km Distances

    2836 km NW Stockholm (pop 1,253,309 ; local time 18:29:58.4 2012-04-29)
    1871 km NW Murmansk (pop 319,263 ; local time 20:29:58.4 2012-04-29)
    1689 km NW Alta (pop 12,077 ; local time 18:29:58.4 2012-04-29)

  9. Hello everyone. I am gonna go to bed,with a lot of new information in my head tonight.

    I’m looking at the eq’s around Iceland. And especially north. I can clearly see that the pattern all over Iceland is following the North Atlantic Ridge. That means they are tectonic, right?

    Well, what I am wondering, is if it’s possible that the ridge is sliding in such a speed away from eachother, that we can get an eruption from more than one volcano at the same time? I do not know too much about the ridge, or about tectonic earthquakes.. But isn’t that what happened to Laki? Kinda?

  10. I guess no one noticed my April 29, 2012 at 21:06 post.

    Long Valley

    “… going over that data, and the quake list. Making a few assumptions, I come up with a fill rate of about 19,289 m³/day…”

  11. Sorry, no, missed that Lurking. So 7,040,485 m³ per year, 7.04 km³per millenium which means 20 years for an Eyafjallajökull-sized fill-up and about 100 kY to top up to the pre-Bishop’s Tuff level. In the short term, nothing to worry about but a hundred thousand years on likely to be a problem – provided the current rate continues.

    • Maybe we should also look this not just in terms of fill rate or volume but heat flux. They system will lose a huge amount of heat over 100 kA and may in the end might have crystallized so much to the point that it is not eruptible anyway. But give that crystal mush a sudden hot mafic injection and you might just quickly turn that mush into real melt, i.e. the question is really how much hot mafic material do you need to raise the temperature of all the silica that is already there. (italicise those last four words for emphasis).

      • Good point! It’s after all what Dr. Shanaka de Silva emphasised in his Q&A over at Eruptions – the critical importance of heat delivery to a volcanic system. Although an eruption never empties a magma chamber completely (with the possible exceptions being cases where the chamber breach has let in the sea), what remains is magma that had already fractionated to the point of being non-eruptible. As an appreciable amount of time has passed, I’d say it is safe to assume that this magma by now has cooled to the stage of being “never-eruptible”.

        With the caldera roof collapsing back into the (partially) emptied magma chamber, the situation at the end of the Bishop’s Tuff eruption ~700,000 years ago would be that to all intents and purposes, the effective magma chamber size would be zero. Since then there have been numerous episodes of magma intrusion, the total volume of which can be fairly accurately estimated by calculating the volome of the resurgent dome.

        In this situation, notice must be taken of (at least) three factors that will have affected the formation of a new magma chamber – a) Fresh magma would have caused a limited remelting of old material, collapsed material as well as ancient magma thus making the total volume of potentially eruptive magma slightly greater than indicated by the size of the resurgent dome. b) This process has been going on for ~700,000 years which is ample time for magma to cool and solidify unless it is, geologically speaking, continuously refreshed. c) Fresh magma will not have entered at or accumulated at a single point, thus the energy induced by fresh magma intrusions will have been dissipated more quickly.

        Now, it is possible to make some assumptions that allow a calculation of the size and energy content of the body(-ies) of magma underneath Long Valley and the effects of the current rate at which fresh magma is injected into the system. I’m confident such calculations have been done many times by scientists with the USGS but because of the many levels of assumptions needed, few if any would have dared to make such calculations public as the highly speculative nature of such results would be a danger to one’s professional reputation.

        • You’re truly a diamond geezer you are! Thank you! Just to be on the safe side, what your animation shows is a system gradually cooling down with time, correct? What volume and temperature did you assign the oldest “never-eruptible by now magma” at the start of the animation? Ditto unerupted but at the time of the BTE eruptible magma?

          • The grids are .25 km square, so it would be a pretty large volume…. much, much larger than the Mogi points at for this batch.

            All I wanted to see was how fast the heat would leave the system. This was a simple 2D run of a dike up into static rock with a rough geothermal gradient.

            I need to fine tune it, the documentation goes more into the heat equations rather than how to use the program… so its a steep learning curve.

          • amazing lurking. I put up an idea and immediately get back a very nifty simulation of the temperature gradients. I feel like some bloke in a white coat with a clipboard in my hand and all I have to do now is to walk around the house saying, “good idea” we’ll run it by the lab.” Ha, the wife is going to like this.

            Now for the slightly grittier task of actually understanding it. What kind of volume is the initial dyke intrusion? Does that actually affect the output or is the 5.5km depth the defining factor?

            The other thing that is probably a factor in large caldera situations is an anomolously high heat transfer from the mantle, i.e. your temperature gradient might be a bit conservative, presuming of course Long Valley still does have a ruddy great boiler under it.

          • No you’re not. There is always a deep source (that can be either a hotspot & mantleplume or a remelting point of a subducted plate. I suspect it’s a combination of both, especially where the total amount of energy travelling through the crust is very great.) The key here is not what’s a few kilometers below the Long Valley shown on maps but what the deep source is, how much energy it’s funnelling upwards and whether this energy is building up or dissipating faster than it is accumulated.

          • The “defining floor” of 5.5 km comes from my guestimate of the intrusion depth. From that list of quakes:

            “5.5” is an artifact of trying to shoe-horn it into the program. ( 0.25 km grid spacing on the mesh )

  12. Hi everyone just managed to get on again.I am not sure how long it will last, as the lap top fan is caput. Time to replace old lappy soon.

  13. OT. Boy I miss all of you. Getting on the internet can be an adventure, we have a monthly amount of 5 gigs, so I have to use the time sparingly. Staying on the net is also a exercise in frustration at times, as the boat swings we loose the signal sometimes, and then have to re-start the computer. Well I have been frantically cleaning everything on the boat, trying to eliminate the brown mold and dirt accumulations. Hubby had to fix the dingy it’s old and tired, and now only has one hole, everything else is in good shape, but still a lot to do before we can leave port. I will keep you posted on our progress.
    Judith and Dean I sure hope things are going ok, and Carl good luck with the move.BBGN all.

  14. Sunday night there as this very deep quake (east of Bárðarbunga)
    29.04.2012 04:25:28 64,669 -17,161 19,0 km 0,6 99,0 12,6 km S of Kistufell

    • HA!

      A pragmatic Yellowstone post!!!

      BRAVO ZULU!!! (means that it’s a job that was very well done)

      This also meshes well with the geologic history of the hotspot and the oddball sizes and shapes of the other calderas that have formed over the last 15 million years or so.

      That is a very interesting read. Thank You!

    • Interesting, thanks! At a temporal distance of 2.1 million years, +/- 0.2% corresponds to +/- 4,200 years (the 1.2% improvement of accuracy on that is +/- 50.4 years, negligible) which means that the proposed interval of 6,000 years falls within the error box. Even so, this is an interesting development. Especially so as differences in composition of the erupted strata suggest that two of the four very large eruptions in New Zealand about a quarter of a million years ago were co-temporal.

    • Sounds probable that it has had more large eruptions, and it also as mentioned explains quite a lot about the odd shapes of the calderas.

    • Yes, seems there were a couple of small EQ’s 10 km to the westsouthwest of Hekla this morning. Still have trouble with the interpretation of strain readings though!

      • Same here! It looks to me as though the SAU recorder has a hissy fit before these little quakes happen, but I’d like a more experienced person than me to confirm this. It all looks quiet now, though, as you say Mike, the strain reading for Hekla is still going up.

  15. I too have been Hekla watching. This quake is deep and has been checked fairly rapidly.
    30.04.2012 05:47:28 63.974 -19.984 5.4 km 0.9 90.02 15.0 km ESE of Árnes
    Likewise the strain at Hekla is onwards and upwards with a couple very sudden drops in the last couple of days.
    Hekla is certainly showing movement that wasn’t there last year.
    Sauber SIL is having some technical difficulties by the looks of it but Mjoaskard is extremely active
    is this or isn’t this connected to Hekla?

    • I thought these sudden drops @HEK are due to rescaling? Otherwise it shoots out of the roof. So i think we will see another drop in the next few minutes.

      • No – they have increased the scale numbers instead. Does this mean the sudden drops are part of what is really happening there?

          • Vertical scale appears “resized” but is designed such as all strain changes 48 hrs can be seen. Program seem not capable of showing real numbers”, except every 1e+04 so one must disgregard those numbers not adjoning the dotted lines. Drops I my mind are area near Hekla “giving in” under the pressure from within.

          • I agree with Islander, I think Hekla drops are formed as new Sils open up lowering magmatic pressure.

    • Yes, Hekla shoots out of her roof. Question is when, not if. I think Carl once said these drops vere but 1/30th of what is expected.

        • I think, HEK first, followed by BUR, dropping in range of 300,000 (3e+05) ? in about 30 min (but big IF) Might be wrong, “not expert”TM *tongue in cheek*

          • Had thought, small strain decrese at HEK now, seems its possible “strain wave from west” (!?) is past Hekla now, can we then expect seeing an small quake south-east of it, Vatnafjöll or Torfajökull, in next hours? I am expecting such. “not expert”TM

    • A very interesting article. Thank you Tyler.
      It’s good to read something positive and objective about Yellowstone. Not only does it put a more clear perspective on large eruptions but it highlights the progress and ongoing study of volcanoes using more accurate methods of recording and investigation.

      • Seems IMO shares our interest in it as it’s already been investigated in spite of it being only a 0.5 (not even half a BigMac in energy content).

        • Yepp, but this is one of the those places that rarely even has a quarter of a Big Mac. But I think that IMO has staff in out of Hekla being strange now.

          • This shows Veidivotn region slowly awakening. Of course, it makes sense since it is part of the Hamarinn and Bardarbunga system. What is interesting is that it is a deep earthquake, 12km.

            So, here’s the question. Does this magma comes from deep down there. Or does it split laterally from Bardarbunga at such great depth?

          • Only way to explain the really large eruptions is to assume that the lava comes both from the parent volcano, and up from the probably fluid magma under that part of Iceland.

          • There’s a lot of strange or unusual activity going on over a very large area of Iceland as evidenced by the tremor plots. More and more stations seem to be taking on the appearance of the Godabunga SIL-station which has been explained as due to high hydrothermal activity. When Grímsfjall took on the same aspect after the May 2011 eruption, this too was explained as hydrothermal activity. Since some twenty more stations now show a similar pattern of activity ranging from as intense to much less so, is this too due to an increase in hydrothermal activity? If so, with the pattern evident from Krafla through Askja, Vatnajökull, the “Dead Zone” (Vatnsfell), Myrdalsjökull and even Reykjanes, does this imply a sudden upturn in the activity of the Iceland Hotspot?

            I really look forward to the Q&A with Dr. Sigrun Hreinsdottir!

        • Henry, I still can’t see that change you speak of, since last Grimsvotn, in the tremor graphs. What is that has changed?
          To me, every SIL seems normal. But you might be seeing something that totally escapes me.

          Independent of that, it is well expected that the hotspot is supposed to surge in activity within the next decades. It is probably already surging in activity. We are seeing this uptick in activity through Askja, increased activity along Bardarbunga and Grimsvotn fissure systems, and these quakes in the dead zone. It might be also that the uptick at Hengill and Krisuvik is related to this.

          • Irpsit, this is how all Icelandic stations used to be (except cyclic man-made “blue” noise near geothermal power plants and roads) – basically three strings of woollen tread; red, green and blue.

            This is Godabunga – high level of “blue” 2 – 4 Hz events.

            Now look at these where the similarity to Godabunga and Grímsfjall is most obvious:

            Vestri Saudahnukur

            (No links for these as the post will be dragon food otherwise)

  16. This has been posted on Avcan Facebook page a person living near Etna.
    live 15 km from Mount Etna Volcanic mouth. This momiento has a long white smoke lengue more or less 30-40 km in the direction of the Calabria. When does so much time erupts. The problem is that lately erupts with more frequency, to intervallos more shorts. The last time eruptò by the evening of 24 April (you can see the eruption of some fotitas I shared on fb). It was a silent erupcion without rain of black sand. What makes me worry is the de facto that once every 300-400 years verify strong earthquakes, as the 1693 in eastern Sicily. If serve comments…. I live on camera magmatica mas grande de vulcano, called volcano of Acireale. :-)about an hour ago · Like · 7

  17. REVISITING that Long Valley heat dissipation simulation.

    I found a more authoritative geothermal gradient of 100°C over a 3 km depth, which is about 33.3°C/km.

    Re-doing the field setup at 50 meter boxes, and keeping the intrusion to one box wide and 5.5 km depth, then running the simulation over several years show that all fresh magma drops below the solidus point at about 64 years.

    In all likelihood, this run is more likely closer to the reality of Long Valley.

    Here are the temperature profiles across the presumed intrusion at various times. Depth is 5.8 km.

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