Sheepy Dalek – Sunday Draft

The rifting which was discussed in the last posts is still happening in Iceland but the quakes seem to have tranquilized a little bit.

Still lots more earthquakes as on a regular day in Iceland in the last few months…

El Hierro seems to go dormant at the moment too. There were earthquakes in the region today but not on the places we watched around El Hierro. So most likely normal tectonic earthquakes.
And the run-up time for Etna next ( maybe) paroxysm is probably at least another week.
As for the run-up for Hekla. This is the very best image i have seen so far from the 2013 (possible) eruption:

Drawing by Icelander

Drawing by Icelander

The Hekla strain meter is still dropping
But this does not show on all the other Hekla stations:

And the alert level was lowered: (Thanks IngeB)

So what to report.
The alert level on several volcanoes in Indonesia was raised.
Difficult to get information on this. There was an earthquake Mag. 7 in Indonesia today.

The riddle pages were updated.


210 thoughts on “Sheepy Dalek – Sunday Draft

  1. Thank you Spica. Interesting to note that in that last picture of Hekla’s activities the bombs dropping were white. Ice bombs? Or more exciting Iceland’s versions of Restingolites. 😀 😀 😀

    • I am totally innocent of that Hekla eruption pic, not done by me!
      *ok, I am “islander” but his done by “Icelander” so must be some other bloke.

      • With all due respect that image was mine. So if CNN needs it they need to ask me first. 😉

  2. Thanks for the post Spica, Interesting to see that Hekla strain is still dropping but no other signs of unrest. Well I am the latest to be eliminated from the Hekla Eruption Sweepstake as my time ran out at 7:00am today.
    Not even looking very likely that the next two on the list for the 9th will guess correctly now either.
    Cowboy Andre April 9th 1pm to 5pm
    El Nathan April 9th late afternoon

    • Oh yeah, predicting a volcano is a very wild guess.

      I (and most of us) did it, based on the fact that most Hekla eruptions (and they are not that many to be a significant relationship) occur in late winter to mid spring months.

      So spring goes April and May. The timeframe most likely for Hekla. My bet is already gone. But someone could pick it right.

      But even predicting the next volcano to go off (in Iceland) is a tricky business. We could say Hekla, Askja or Katla. But what if Krisuvik, Kverfjoll, Hamarinn or a submarine volcano at Tjornes surprise us?

      The volcano world is full of surprises.

    • So when this Hekla strain build up is big enough, bigger than the bedrock can bear with, things could goes bang then?

      • Hekla is essentially, a large rift cone. So large that is has characteristics of a stratovolcano. When one side’s strain massively operates the opposite of the other side, it can cleave open.

        Hekla tends to be eerily quiet with the quakes. Most volcanoes give you a heads up with quakes, Hekla tends to “sneak it out”. In fact, for Hekla’s last eruption, the quake swarm started about 61 minutes prior to it popping the cork. Even with that, the quakes were not humanly detectable (in other words, with no equipment) until about 15 minutes before full on eruption. This hazard is one reason Hekla is not safe to hike on right now. You get virtually no warning if you are just standing around on the top of it. By the time you feel the quakes, you probably wouldn’t get very far before it went off.

    • Partially related.

      If you run across a table in a pdf document, you can highlight the table and data and with a right click, occasionally have the option to export the table to a spreadsheet.

      I’ve used this many times when they send me my inventory data in pdf instead of spreadsheet format. It doesn’t work on all pdfs, but it does work on many of them. Even a few geology and volcano related ones.

      (file under “stupid data mining tricks”)

  3. Its Sunday. I’m doing something that I haven’t done in a while… watching a NASCAR race. (go fast, turn left)

    One of the entertaining aspect of it, is listening to the commentators. They can be… puzzling in the choice of words that they use. “Delta,” (δ) as in the ‘amount of change’ is not something you ordinarily hear in a non math setting, yet one of them used it when referring to the handling of the cars. It was proper usage, but I’m not sure that many of the viewing audience picked up on it. We are, after all, supposed to be knuckle dragging cretins if you listen to the stereotypes that are used by the MSM.

  4. Repost from the TFZ-Thread: (thanks schteve42)

    Hi GeoLurking, tgmccoy, Peter, KarenZ, Diane and inannamoon667

    Thanks for all your Advice, I think that you really helped me to clear my mind. I was able to get in touch with the agency which was helping me with the booking of the Cambridge Course in Vancouver. First of all, the option of part time studying wouldn’t have worked, because I’m from Switzerland. Now I’ve had three days to think about your recommendations and the advice from my friends and family. I really would have loved to study english in Vancouver, but the Job is simply to good. Tommorrow I’ll tell my new employer that I’ll cancel the booking for the english course because I would love to work with and for them. It really is a dreamjob in a great local advertising agency with great clients and an awesome team. There is a lot i can learn from all of them and in the end, I can allways study english later or go to an evening course in a local language center. So in a few hours, a new phase in my life beginns and with some time passed, I think I’ll not regret that decission.
    And just for info, I’ll only have to pay some administrative fees (~200-400 Dollars ) and not the whole costs of the course.

    So again, thank you all for your help in those difficult few hours in my life.

    Best whishes from Switzerland

    • Congratulations for getting the new job. You should be able to find a good English course in Switzerland.

    • Glad to help my Gr.Gr. Grandfather was from a little village near Zurich. Ended up in
      West Virginia, married one of Native American ancestors. Always wanted to see Switzerland…

      • Hopefully it was peaceable.

        Dunno how far back it was, but I had an ancestor with a wife and a mistress. The offspring of that arrangement never did get along. The family actually had a feud with itself which eventually led to a self imposed diaspora throughout the county for safety reasons.

        • Now that is a lovely word I haven’t read for ages. The last time was many, many years when I was reading up on history of the Middle East areas and came across information about the diaspora of the Jews. I do love words and especially the etymology of them. In fact the English language is so fascinating just because of the multitude of words from so many different languages.

    • Stefan. Congratulations. My Son, Rob, has just gone freelance Copywriter. This after a long and upward climb in the advertising industry. He now earns figures I could only dream about. If you wish to know more I would happily give you links to his career to date. This just so that you know where you can go. Rob was never “Academic” I think he inherited my anti- math gene. 😀 Despite lack of high “academic” qualifications ,what he does have is self motivation, some no mean artistic talent and a quick wit.
      After a rather unorthodox route he did gain the highest degree grade in Advertising but it is his personality and abilities that got him the jobs. His ambition was to work for Saatchi. After years they actually head hunted him. His accounts included Porsche……and the bonus was he had to drive the cars before he could write about them 😀 😀 Another was UNICEF and he was sent to Africa to take photos and again create ads. So you are about to embark on a career in which the only boundaries are created by yourself.
      All the very best for the future and well done. XXXXXX

      • Hi Diana

        Thank you for all the lovely words and your great advice, I really apprechiate it and I’m very glad that there are so many great people like yourself, GeoLurking, Peter, and many more in the Volcanocafe. For now I think everything has worked out fine for me (from a job-perspective), even if there were a few hard weeks I had to go through (grammar?)

        Thanks to all of you I can now again focus my energy on beeing creative in my job and enjoying reading about all the volcanic burps and bobs in the world. 🙂

        Best Whishes to all Volcanophiles 🙂

    • Not often I comment on stuff apart from Friday riddles, but must say well done to you Stefan for choosing the advertising job over the language course. I am a bit biased though as I worked in advertising sales for many years and loved every minute of it. Had to give up that career eventually, long hours and children do not make for an easy life. The kids grew up but the industry is so different now, I wouldnt even consider the challenges….am too old anyway 🙂 Happy to say that my daughter had planned a career in Law, got her degree and everything, but Law was not for her and she made a ‘leap of faith’ just like you and now is an account manager working for the number one agency in Scotland. They have just opened an office in New York and she may well move over there for a while to help set things up – her Dad is American, so that helps a bit. Anyway what I’m trying to say is that you will win if you want to. It’s hard work, long hours and sometimes you will wonder why you do it….but in the long run, nothing beats the satisfaction of being part of a winning team. Media agencies are reknowned for having a ‘work hard, play hard’ attitude – so there are many social benefits if you are up for it, don’t party too much on a ‘school night’ though 🙂 Go for it – and btw I think you will pick up the English language pretty quick without a course, the new job will probably help you on the way.

      • Hi Kelda

        Thanks for the encouraging words 🙂 I know, advertising is hard work and that means long workdays, but with the right clients, a great team and dedication to the job, it will be a great reward. For now, the first week in the job is almost over and I’ve had the opportunty to work on some great projects. Also I was allready able to learn some new things I didn’t know before, thats cool too. 🙂

        Now I whish you all a happy Friday and a good start into the weekend.

  5. while things are ‘quiet’ for now, it is a good thing to have a look what a volcano can do hence the recent history of the largest eruption in the last century of Mt Pinatubo

    • I think this should be made compulsory viewing for all Volcanoholics. It’s tense, frightening and reminds us not to become complacent. Mostly it should remind us what not to wish for!
      I know that technology and monitoring has moved on since Pinatubo but throughout watching this I am thinking of places where evacuation will be more difficult. such as Vesuvius.
      it also highlights the “on ” Off” “on” Off” activity. The huge difficulty of prediction. Hats off to the professionals who bear such responsibility. I am sure others will think “Bob”, although Bob and Possibly Bobbette are but small compared to these giants.

      • Also hats off to the Director of the Philippine Inst of Volcanology for recognising that there could be a problem.

        Interesting the area covered by EQs preceding the eruption.

        • Carl rated PHILVOC as second only to IMO in terms of expertise, hazard mitigation and all the other extremely complicated aspects of being the “authority” on volcanoes and seismicity etc.
          Annndd I have to say the situation in the Phillipines is far more difficult.
          There is a vastly larger population with a much higher proportion of them “living off the land” which meaans they will be living in the fertile volcanic regions etc etc
          And the potential for massive devastating eruptions/ events is much higher int Phillipines…

  6. So, the Hekla strain meter starts it’s dive again. In contrast to the beginning of the post this trend seems to get clear as well from Búrfell, Hella and Stórólfshvoll.. or do I make a mistake that these are in the vicinity.

    • One @ 19 km and all others above that-even an 8 and last two @ 11 km. I saw last animation by schteve going deeper-but that doesn’t seem to be happening now.

      • Hi Maggiemom

        sorry to be a wee miffed up there. I don’t think schteve does animations. I do. Schteve has many other qualities of course.

      • Hi maggiemom and Dfm,
        I planned to point out the mistake when I got home from work… but you’d already got there…
        I do do animations actually, but it’s been a long while since they’ve been seen here… 🙂
        I’m not set up to do the 4D rotating singing dancing stuff though.
        The position of the animation in the thread and the way my comment was phrased could easily have given the impression that it was my plot, but of course that was not my intention… 🙂

          • Careful which music you choose, it may alienate some of yr viewers, how about some Ravel; La Valse perhaps or even Bolero… 😀

        • Totally my own fault for not scrolling farther up. . .and should have known intro is before animation. . just a goof up.

    • Found via Erik Klematti’s Eruption Blog, a seismic profile of activity at El Hierro posted by GuillermoChile:

      • it’s a Delaunay triangulation. I’m not over convinced especially as I do not know if they trimmed the data beforehand…..but the picture is pretty.

      • I’ll let Karen do the detailed explanation of her plot.
        Vs and Vp are the velocities of the seismic waves (P and S) that you see on the seismograms. They are affected by the nature of the rocks and the presence of liquids and gases. Some techniques, mainly used in the petroleum industry use theses velocities to locate oil or gas.

      • Earthquakes generate several wave types: compressional (P); shear (S); body and surface waves. P and S waves are used to determine the time and location of the orgin of the earthquake.

        Vp is the speed of the P wave – the first wave arriving at the seismometer
        Vs is the speed of the S wave – the second wave arriving at the seismometer

        As dfm has stated, the waves are affected by the nature of the rock they travel through. For example. S waves cannot travel though liquid.

      • Very interesting. Thank you, KarenZ. 🙂

        Would somebody among you perhaps be interested in doing a plot about the TFZ quakes series in Iceland? (hint)

      • Great plot KarenZ. I’m tringing to crasp what you plotted. In the center of the swarm you clearly see less S waves. So i quess it’s more liquid there. The quakes furthest out are more P wave rich. Could be breaking of fresh strata due to stresses from the influx of magma in the center. I think these his deformation/cracking/quake are causing crevices for the magma to poor into. Does this make any sence ?

        • To calculate the ratio of Vp to Vs, you have to match the P waves to the S waves, so there are the same number of P and S waves in the plot.

          • Hi karen, well ofcourse they come in same numbers, but the ratio you ploted means wich one is more evident in the signal or not? 0.6 means a very low S ratio. 6.7 would mean a stronger S signal. Or is it about te diffence in speed. differnce in arival times ?

  7. Yee Haw. “The Excitable Ones” are jumping up and down about nuke weaps and EMP and that certain subs are unlocated. None of the vessels that I know of have a “boomer” capability, unless someone has managed to work out how to do a ballistic missile out of a 533mm torp tube. (purchaced cruise missile tech is a possibility though) Then there is the prob of EMP dynamics. Even at optimal speed, the sub crew is gonne be quite “ripe” by the time they reach Hawaii. (something like 360+ hours non stop, not counting the fuel issue on a diesel boat.) Provided they can do it.

    Spooky? Yeah. Loonatics usually are. Add to that that NK is a bit unpredictable also.

      • two NK subs “missing” is absulut peanuts to worry about, re attack capabilities, only them on “one-way mission” they be used as flame-setter (then we hope it be recognised as no real further threat, for prevention of escalation) *sad face*

        • I agree on the peanuts aspect of it. I find it laughable that someone thinks that these boats can shuttle a ballistic missile to someones shore and then launch it.

          Open ocean transits are not the easiest thing to pull off for a limited range diesel boat. Subs roll like a son of a @#$@# at the surface and thats where you need to be at to get air. (snorkel). Potentially puke central for even the hardiest sailor… or getting slammed into a piece of gear. (done that… not fun)

      • Dunno. I had to sift back through news articles to even find evidence that any got underway. As for missing, to us, the civilian populace, a sub goes “missing” once it dives since we have no way of tracking it. The Military on the other hand, {usually} can track them. What is “missing” to us is generally not missing to them. It doesn’t mean that something can’t be missing to them, just that its usually not the case.

        None of NK’s subs are ballistic missile capable. They don’t have really long legs and they take forever to get somewhere. A Diesel on batteries can be very quiet if the equipment is designed properly and you have good crew discipline. If a particular sub is a threat and they loose track of it, the area will generally get flooded with assets in order to re-aquire it’s location.

        One thing that a sub can’t counter is mad gear. A P-3 Orion can stay on patrol for an obscene amount of time. From geology, we have all seen the magnetic anomaly maps. That technology came about (in part) from the military’s Anti-Submarine Warfare work.

        My main concern are those 533 mm tubes. NK has done quite a bit of trade with Iran, and Iran reportedly has test fired Шквал torpedoes (ostensibly acquired from Russia). They are used in 533 mm tubes. Essentially, they are 200+ knot torpedoes.

        If they have them, and if those small subs are dispersed to wait it out in key locations along the shoals (they can bottom and hang out, almost invisible) then they could be setting up traps. Even with normal torpedoes they would be an effective surprise.

        Recently, Japan’s PM told the JDF to shoot down the next missile that NK launches. Both South Korea and Japan have Aegis boats, but I think only the Japanese ones carry the SM-3 missile. SM-3 equipped ships are the only ones that have a chance to pop a ballistic missile… and they probably have to catch it near the apex of it’s trajectory. I know the SM-3 can do it, it was first tested against ultra high altitude targets on the R.K. Turner. (part of one seriously bad ass AA cruiser class that was deemed obsolete) The SM-3 essentially uses the whole SM-2ER ensemble as a boost phase for a Lightweight Exo-Atmospheric Projectile. Given the phenomenal capability of the SM2-ER tracking and engagement gear, I can see why the SM-3 would be as capable. Not getting skin to skin was always a problem on test shots. (you’re supposed to miss by a certain distance so that the other ships can shoot at the test target)

        Here are a collection of SM-1 and SM-2 shots. The ship use a missile director to illuminate and track the target. These are large gimble mounted parabolic antenna covered with a radome. They always reminded me of the ED-209 from the movie RoboCop. (about the right size, loaded with servos, and just as un-predictable to someone standing nearby when they activate)

        • fairly well versed (for average person that is) in all things subs and patrol planes, from wartime PBY-5 (Model 28) to P-3C Update (default), about time for the P-8 Poseidon to burn some JP-4 lo-level 😉
          Otherwise modern subs do not interest me, but seen one or two old diesels in port.

          • Subs never were of much interest to me either. But being able to discuss the threat with the wardroom was something that I always had to be able to do.

            Personally, I think there is a world of shit to be had. It just depends on who gets the stinky end of the stick.

        • Magnetic anomaly detection is of very little value these days as it only works over very short range and against subs at shallow depth. It has largely been overlooked in ASW for many years, and was used really only as a last-chance check to make sure that you had a real sub as opposed to a whale just before prosecution.
          As far as I am aware the US Navy’s new P-8s don’t have MAD (although the Indian ones do). The US Navy figured that as the P-8 is primarily intended for a high-altitude mission where MAD is useless the extra time on station gained through weight-saving is a lot more useful than lugging around a hunk of draggy 1950s technology.

          • What would you consider shallow depth? The Sang-O shows a max depth of 150 meters. (but then it is a follow on to the Yugo midget sub, and this is Wickerpedia data)

  8. most of the Nork boats are of Russian either Romeo or Whiskey class subs. Both copies and improvements on the German XXIV u-boats. but they are still old diesel boats. IF they are smuggling a Nuke they should have a fair radiological signature.-unless it’s a Plutonium bomb.
    Not to say they can’t do it, bu ti think we have an idea where they are..My concern is they can use a disgused “milch cow” for supplies and cover…

    • “Know your enemy” A saying we all know but who said it?
      Sun Tzu was an ancient Chinese military general, strategist and philosopher from the Zhou Dynasty. He is traditionally believed to be the author of The Art of War, an extremely influential ancient Chinese book on military strategy.
      During the 19th and 20th centuries, Sun Tzu’s The Art of War grew in popularity and saw practical use in Western society. His work continues to influence both Asian and Western culture and politics.
      “Know your enemy” is good advice in any situation from something personal such as Job interviews to the world of warfare and the present sabre rattling from North Korea.
      However sometimes it is impossible to understand exactly what is going on and to make any informed predictions. Just like Volcanoes it is not always easy to interpret the outward signs accurately as observers have little experience of hidden construction or true strength of fire power.
      I think this quote from Sun Tzu can be applied to any Challenge whether personal, scientific, (Volcano watching and the challenge of prediction ) or military
      ” In respect of military method, we have,
      firstly, Measurement; secondly, Estimation of quantity;
      thirdly, Calculation; fourthly, Balancing of chances;
      fifthly, Victory”

      Here endeth my morning rumination and coffee #1 >>>>>>Potters off to get coffee #2 muttering something about how Lurking and tgmccoy always seem to somehow get her going by their written antics whilst she’s fast asleep………..

    • Most likely to have very little radiological signature. I spent 21 years working with nucs while in the US Navy and total exposure was .43 millirems. Until they go bang there is not a great deal of radiation.

    • Obviously people underestimate NK a lot. An enemy in war would of course like to give the impression of being weaker than it is and hide its weapons.

      Also: NK being in a state of war for 60 years, had plenty of time to prepare and develop weapons to attack the US and also to spy on them. It also had the help of its former ally the Soviet Union, through a obscure border.

      Also did a lot of tunnels, so there is plenty that they develop we simply cannot observe.

      If it has smugled a nuke over the US, or delivers a single EMP over its atmosphere, it is already game over for the US. And since this has been known for decades, the US already has a change of losing quickly and dramatically a possible war, especially when it stands so arrogant thinking that NK is a rather “weak” opponent possessing primitive nukes and balistic missiles.

      However likewise, I am sure that the US possesses many secret weapons and secret plans to defeat NK. I just do not understand clearly if one opponent already developed these, why it had not use them yet. Of course there are the catastrophic consequences everyone would suffer. And perhaps no one wants to open another pandora box.

  9. With respect to Ursh ‘s Comment and accompanying video of the Pinatuba eruption (Ursh says: April 8, 2013 at 09:02 )
    I thought of the scenario of Vesuvius starting to grumble. What a nightmare! Much as I would like to be a professional Vulcanologist, in this situation I would not like to be in their shoes. This is one place where I think sleepless nights and major stress would be understatements for those brave people.

        • Yes, I think that too, and the collegueas at Catania are also doing a great job. 🙂

          BTW: I don’t know which one is worse, Vesuvius or Campi Flegrei.

          • Don’t think that all the plates on earth are moving more than usual at the moment (prove?). And heightened activity at iceland’s volcanoes could partially be due to climate change (glaciers melting, land uplift etc.)

            Also meteors have nothing to do with volcanoes.

        • I think Vesuvius is more of a problem, Campi Flegrei is always active bubbling away keeping energy releases in check, I think/hope, looking at Vesuvius gives me an uneasy feeling, always has, even Etna is more active lately, maybe the African plate is putting more pressure on the European plate, getting more energy/lava to form which has to go somewhere, all the plates on earth are getting a bid more of a workout in the last couple of years. There is a saying as above so below, Iceland in the north, NZ in the south to name one, Meteors etc in the sky versus undersea volcanoes, just thinking

          • Campi Flegrei is not always just bubbling in the same way, there were uplift episodes up to some meters, changes in gas composition etc. Parts of the population centers of the Naples area are literally sitting on it. And it is a big caldera.

            The Civil Protection services were rather concerned not so long time ago.

            Erik Klemetti on Campi flegrei caldera:

          • Ursh, the fact that a volcano bubbles (geothermal activity) does not release any pressure by any means. It is just a sign that there is magma near the surface that heats the water and mud.

            The scale of comparison is astonishing. Just a small amount of magma stuck next to the surface makes water boiling. But its a large amount of magma in deep that can create further pressure.

            Just cause Camp Flegrei “bubbles” does not mean it is near an eruption or very relaxed and away from an eruption. Example: Grimsvotn has large geothermal activity and erupts often. Hekla erupts often and has no geothermal activity. Geysir has geothermal activity and rarely eruptions. And some volcanoes (like Snaefellsjokull) rarely erupt and do not show any geothermal activity. So, one thing has nothing to be with the other.

            However, if geothermal increases or changes suddently, it can be caused by a influx deep of magma which creates changes in geothermal activity. This is what happened with Katla in recent years, but per se, does not mean a pending eruption for sure.

          • So far, an increase in earthquakes together with deep earthquakes, and sustained inflation seem to be the better indicators of a coming eruption, to any volcano anywhere. But still they are not sure indicators. Sometimes volcanoes do not erupt with all these signs. And sometimes they do erupt without any of these signs! How about that? 😀

  10. OT – Apologies to any Argentinians who pass by here, but this is outright funny.

    An Argentine man who thought he bought a pair of poodles at an outdoor market in Buenos Aires brought them home to the vet only to be told they were actually ferrets on steroids, reports the Daily Mail.

    The man, a retiree from Catamarca, purchased the animals at La Salada, Argentina’s largest bazaar.

    The veterinarian informed him the ferrets “had been given steroids at birth to increase their size and then had some extra grooming to make their coats resemble a fluffy toy poodle,” the paper says, translating a report from a local Argentine TV station. He paid $150 per poodle.

      • ROFL ! I had not seen the pictures ! The guy’s blind or what ?
        ” come here, heel ! Argghhh it chewed my finger ! bad doggie ! ”
        Never trust a poodle they are vicious dogs….

          • Knew a Yorkshire Terrier that did that- neighbor in my old town had a quite cute
            18-year old daughter-she fell in with this klown that was abusive to her- one day,
            he finally decided to rough her up while her parents were gone. The yorkie went up his pant leg and proceeded to chew on the way up; 33 stitches worth he bolted out of the house trying to get the yorkie out of his pants..The girl had a black eye. We saw the
            whole dog shaking episode.
            The yokie, ‘Luvvie” got a steak dinner that night…
            He got charged..

  11. Quite a funny coincidence,

    Three days ago a 6.0 earthquake in North Korea
    Today a 6.5 earthquake in Iran.

    With all the current war tensions, this sounds like a funny coincidence, or secret and undisclosed tests by those nations, or tests of a secret weapon creating earthquakes by the US or any other third party. Or “God” has a sense of irony.

    • And of course, the epicenter of the earthquake in Iran is right in Iran’s nuclear site.

      These quakes are as a striking coincidence as the Russia meteor happening in the same day as the fly-by asteroid, but different trajectories.

      I must say I am strongly skeptical of coincidences as big as these ones.

      • How about a GeoLurking?

        The Iranian Quake had what appears to be a pretty solid focal solution with 86 stations contributing. Had there been anything fishy about it, I’m pretty sure someone would be raising unholy hell about it. The solution seems to match the prevailing fault systems.

        It also has aftershocks galore and they seem to be following the Gutenburg-Ricter power law. (yet more evidence that it was just a quake)

        As for power, at about 2 megatons, it would have been quite news worthy, and Iran would be jumping up and down about it like a kid who just discovered his “extremity”.

    • Just as the Roman & Greek Gods enjoyed playing with human life paths I am sure “Him Up there” by which ever name you know him likes to keep us on our toes. I have always been of the opinion that “Heaven” would be a pretty boring place if all you do (If you get there) is play harps and lounge about singing with the angels. So There must be many times when the human race is “tested” to relieve the monotony. 😀

    • my thoughts, if quacks like a duck…..the main quake in Iran was 89km from the reactor and it was reported to and is regarded as save by the international…

  12. This sloping trend on Hekla strain, do you think this pose somewhat a higher risk to generate earthquakes?
    I mean, something could possibly break apart if the strain is big enough.

    • The strain seems to me to be going down rather than up at the moment. It does not seem unusual to me (except that it usually goes up) but I will wait till one of our Icelandic friends comment. 🙂

      • I have no idea if this downwards trend in Hekla strain is normal or not. So far, no earthquakes as of lately. Hekla is really hard to figure out!

    • The only thing I know for sure about this chart is that they keep resizing it and I have no idea how to read it at all apart from the fact that it seems to go down for days then go up for days, (with minor changes of course) whereas up until now I haven’t noticed that the other charts, Burfell, Hell and Sto show such a slow rise up and down. Having said that the overall trend of them all seems to be generally downward in the last few days. What this signifies for Hekla i have no idea!

  13. @ inge : TFZ plot is on its way

    @ Volcanic : I did a few plots myself on VP Vs , poisson ratio and the like a few months ago. You can find them on my YT channel. I made an assumption, by computing directly Vp and Vs from the arrival times. I know the calculation is wrong, but I choose this method for simplicity and to get an approximation on the results, just to see if it showed something. KarenZ calculation I think was a bit more complex. It would be interesting to compare the results.
    I think you have a better understanding so feel free to comment.

    • Calculation for the Ratio of Vp to Vs is a straightforward ratio of the P wave and S wave arrival times.

      The calculation for wave velocities is a bit more complex, but not used above.

        • Very simple mathematics:

          Vp = X/Pt where X is the distance between hypocentre and seismometer and Pt is the time the P wave takes to reach the seismometer.
          Vs = X/St X as above and St is the time the S wave takes to reach the seismometer.

          In the ratio of Vp to Vs, X cancels out so you are looking at the ratios of the wave arrival times.

          • No, you don’t. You are looking at the ratios of time travel, not the arrival time. Not at all the same.
            Suppose two earthquakes located at the same place (same mechanism) and recorded by the same recorder but at two different times (one hour difference). The distance is the same, only the arrival times differ. I should have the same ratio.
            First one: Pt = 23:00:01 and St = 23:00:04
            Second one near midnight Pt = 0:00:01 St = 0:00:04
            According to you I compute 23:00:04 / 23:00:01 = 1.000036231 (Excel time) and St/Pt = 4. Huh ?

            What is kept constant is the difference of time between the two arrivals.

            Now the earthquake occurs (first case) at 22:59:57
            Travel time second case: P: 23:00:01 – 22:59:57 = 4 second
            Travel time second case: S: 23:00:04 – 22:59:57 = 7 second
            Ratio : 7/4 = 1.75

            Second one at 23:59:57
            Travel time first case: P: 0:00:01 – 23:59:57 = 4 second
            Travel time first case: S: 0:00:04 – 23:59:57 = 7 second
            Ratio : 7/4 = 1.75

          • What’s the real issue?

            Most EQs had Vp to Vs in the expected range; i.e. 1.73. +/- You can tell from the plots that most values fell in the expected range.

          • Yes I think there is a little misunderstanding. The velocity means that you’re using arrival time and earthquake time given by the ign data to calculate the velocity of the wave by using travel time. That’s all.
            So there’s apparently not a lot of “strange” values. So no magma intrusion ?

          • Dunno – about no magma instrusion as I have not found expected Vp to Vs ratios for magma, rocks near magma or crystalline mush. There are values outside the range 1.5 to 2.0, and even 1.5, itself, may be an odd value.

  14. Spica, we hang on your lips and seem to be a really eager bunch 😉 !
    This is my version of the eq matrix:

    The current swarm is well within the range of previous swarms, but there are some significant deep earthquakes down to or below the assumed Moho. I am still impressed about how the eq swarm is contorted, which I think is named décollement, or basal detachment faulting, which can occur in extensional settings.

    Here is reported that the Grimsey lineament is extending 5 mm/yr and one can distinguish between superficial and deep dislocation in the TFZ.

  15. Wisdom caught in the spam dungeon: The particular elevator for you to success is out with friends involving buy. You’ll need to utilize the stairs… just one move during a period

  16. Hello all! I am delighted that some of you find my webcam collection useful (I know, some others put watching webcams in the same league as knitting scarves 😉 ) I have somewhat beautified and added my page for Indonesia, with mainly the “back cameras” as georgiade said above, from the badan geologi website. Now, from the 11 cams I have there 7 are not working… If one of you knows of another volcano webcam in Indonesia or on other Pacific Islands, please, please, let me know the link! Thanks in advance!
    So far I have
    Lokon, Ijen, Tangkuban, Sinabung, Merapi, Semeru, Papandayan, Galunggung, Bromo 2x, Yasur (Vanuatu). There are supposedly 2 more in Vanuatu, but I cannot find them.
    And this the link to the Indonesian page:
    Any suggestions for improvements are welcome!
    Good night!

    • Sorry, but just after I posted the link, the server went down 😦 Must be something serious because that has happened only twice in the last 6 years…

  17. For all.

    Do not forget that earthquakes occur when rock fractures. The hotter the rock at a given pressure, the more ductile it is. (bends or oozes). If the stress accumulates faster than the rock can bend to accomodate it, you can get a quake.

    This reminder was brought to you by the number “blue”

  18. This blast Bruce?

    Inge B mentioned Etna earlier in the tread, keep watch on this volcano. If Dr. Boris says it is getting worked up for the next paroxysm ( that would be #10 this year right? ) it is most likely happening.
    Etna does burp without a rising tremor occasionally, But ever since i watched it, the tremor was always rsing high before a full beautifu paroxysm happened. So we should pay attention to this site, and we will be ready to watch the cams.

    • I guess that was it Spica. There have been a couple more since. Seems to be picking up. I can’t remember the activity before the paroxysms ever being so, um, vulcanian, I guess is the right term. Etna looks more like Sakurajima this morning than Stromboli.

    • Thanks for posting the pictures Spica, I too missed it. This is the first time I have seen Etna just ‘burping’ so find it really interesting.

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