Tanganasoga Vulcano Inflation

Photographer: Unknown, all rights reserved. The baren volcano of Tanganasoga.

This will be a rather short post. During the last day I have received some information regarding Tanganasoga. Apparently it has been known for some time, but held back from the general population of El Hierro, that Tanganasoga is suffering from rapid inflation due to magma injection.

The Inflation

Even though I had two individual sources stating this, I still wanted to have additional confirmation before I wrote about it. After all, now we are talking about a volcanic feature that possibly can cause fatalities. So to get a bit of confirmation I asked GeoLurking to make a plot of the current uplift. It seems to indicate that there is an ongoing inflation in the Tanganasoga volcano.

Image: GeoLurking. Inflation hypocenter of Tanganasoga

Carbon dioxide map

CO2 is one of the premier gasses when you try to judge a volcanoes state. If you have an increased emission from a volcano you have yet another precursor to a possible eruption. As can be seen on the image below the area of Tanganasoga is leaking CO2 quite badly right now. The northwestern red area is related to the Roques de Salmor gas-vent.

Image: Unknown creator. Several zones of high CO2 release in and around the Tanganasoga volcano

Tanganasoga inflation

The inflation of the Tanganasoga Volcano puts strain on the rock face pointing down towards the village of Los Llanillos. As the rock face is put under strain it will sooner or later start to shear and parts of the rock face will start to come loose and fall down.

There is also a small risk of a lateral collapse of the mountain side if an eruption occurs at Tanganasoga. I am not saying that it would be like Mount Saint Helens, the pressure is just not there. But, between 0.5 and 2 cubic kilometer of rock going down into the bay is not good news. And then on top of that, magma flowing down after the falling rocks. Well, I for one would not like to be in the way of it all.

Let us be clear on one thing, I am not saying that there will be an eruption at Tanganasoga. But the pressure build up on the rock alone requires diligent monitoring. And the political will to evacuate Los Llanillos if there is an increased risk of a larger rock fall due to mountain tension. If the risk increases even more, which I think is likely after seeing the CO2 map. They need to make serious preparations for evacuation of everything from Frontera to Sabinosa. Because if there is an eruption at Tanganasoga there will be rockslides, magma flows, and yes even the small risk of pyroclastic flows. And it will all most likely be going into the town of Frontera, so there is not being any leeway for risking a non-evacuation. It is time for the small boys of IGN, Pevolca, Involca and the rest to grow up, and grow a pair.


559 thoughts on “Tanganasoga Vulcano Inflation

  1. @Lurking I asked a question on the previous page of comments, but that is now far up the thread so reposting here – is the total uplift over 11 days approximately 1cm ? or have I misread the scale on your plot (in which case I’d guess total uplift in that time approx = 1mm)

      • I think (if I’m reading it correctly) the reddest area in Lurking’s plot would have been 16.5mm in 11 days or 15mm in 10days depending on whether the dates are inclusive/exclusive. I was just rounding for simplicity earlier – as I was just checking I was not out by an order of magnitude.

        But yes Lurking is extremely talented at this plotting malarky, and either way the figures for Tanganasoga sound worrysome.

    • It’s totally incomplete. I have not seen one single reference to the thing’s real name, “Bob”.
      And where are the links to our cafe and Jon’s place? Wikipedia is no more what it was. I shall buy some books again in the future… 🙂

  2. Short update:
    “The voices” that I seem to hear in my head have spoken again. I would have written a new post, but since I am chairing a shareholders meeting for a stock market company this evening I will probably not have the time for it.

    So, short and to the point.
    1. A confirmed new larger vent has opened up closer to the port. (Which you guys spotted dead on locationwhise).
    2. The quakes at Los Llanillos is seen as a precursor for an eruption on a line from Tanganasoga down to Los Llanillos. Unclear exact spot for eruption yet.
    3. Expected precursors for the Tanganasoga – Los Llanillos eruption are to probably start within the next few days.
    4. Due to the “nature” of the earthquakes lately it is expected that a 5M+ quke will happen in the next few days, that is expected to be the start of a new eruptive process.
    5. There is a marked pulsation in the tremoring, the pulsation cycles get shorter and shorter. Currently they are in the ball park of 6 – 8 hours. The reason is probably gas-release events.
    6. Expected termination of Bobs tube, due to critical failure.
    7. Gas emission rates are (not quantified) “spectacular” around Tanganasoga and rates of inflation is “above” 1mm a day.
    8. The gas emission types and other “markers” are consistant with an expected explosive eruption.

    The list above is one thing, but the language is more like panick-stricken. Two different organisations are going apeshit after going through the data and are screaming at IGN… One of them have taken in a consultant (read foreign real volcanologist) that corroborates the expected events to occur as above. And that consultant is a large name with vast experience on erupting volcanos in Europe. Still, after all the evidence IGN is saying that nothing will happen, internally they seem to be in turmoil too.
    I will restate this phrase again. I hope that IGN will grow up, and grow a pair.

    • After the last couple of days’ ‘work’ I am less concerned and am tending towards the “nothing serious will happen” IGN camp. The reason is that I think maybe IGN have spotted something very unusual early on. If it is what I think it is, its rather a new phenomenon to volcanology, and not seen before in Europe. If that phenomenon has occurred it means that there may not be a huge mass of fresh magma intrusion. I just have a diagram to make and will then send it to Carl as a new post.

    • IGN still seem to focus on the dangers of landslippage rather than an eruption. Lack of experience, may be.

      But this has all the hallmarks of a creeping (or now not so creeping) disaster.

  3. The webcam now seems to be showing a new vent over the left hand harbour wall. It is being moved about a little so the wall can be seen.

  4. Wow, just came on the computer 15 mins ago and that stain looks closer to the harbour wall every time I look. And a fair amount of bubbling too. Not looking good for people in the Los Llanillos area is it. I would leave right not if I was there, I would beg in the street rather than stay there at the moment.

  5. I worry about the people of Hierro. They must be very confusing. Everywhere there are new symptoms and no one will clarify anything. Only data and more data, but no explanation they can understand. It must be frustating.

  6. How deep is the sea on this new location nearer the harbor do you think? This location seems to be the same I saw some disturbance a week ago or so, commented in the “other” blog

    • Very Nice! I like that you brought the point of view in closer.

      One issue that I’m always fighting is whether to outline the points or not. When you outline them, they stand out better and you get a better spatial feel for where they are at, but you loose some of the color coding resolution since it’s harder to make that out.

      I usually have to ask myself what exactly it is I’m trying to illustrate.

      Dunno if you can do it with your program, but if you can bump the vertical resolution a bit you won’t have those gaps in the depth portion of the plot. You may or may not be able to do it with your program, but that’s about the only thing I would change.

      • Colour coding here is important as I was plotting location, depth with magnitude as the attribute. The only way to show magnitude here was by colour. May be I should have put a better key in the intro. Could make the points bigger but then the real gaps would be hidden as well. But I’ll look into it. Thanks for the feedback.

      • Yes, very nice, Karen!
        Lurking & Karen, something you can do to make certain points stand out better is to use, for example a cold-colour -> white -> hot-colour graduated colour scheme (standard practice in thematic cartography). E.g. in this plot I would use the following:
        dark blue = less than 1 magnitude
        light blue = 1-2M
        light red/pink = 2-3M
        bright red = 3M
        That way the largest earthquakes visually really stand out, because they are of a bright primary colour (red) and catch your attention.

        • Agree, but it gets to be a pain in the arse chasing the magnitude scale up and down and setting colors each time I render a plot. I usually go for an upper and lower extent and let the gradation show the relative intensity. It yields a higher resolution in how strong one quake was in relation to it’s neighbors rather than dropping them into a magnitude bin.

        • Tried your suggested but it was even harder to see the distinction in size of EQs – too many blue blobs hid the red and red/pink. The larger EQs have to be in a darker colour to be seen.

  7. For thickos like me who need pictures to understand anything, try the flight sim feature on Google Earth to get a true appreciation of just how damaging any sort of event could be on the north side of El Hierro. A few minutes of fun as well, but certainly provided a good perspective.

    • Know what you mean. Seing is believing. Astonishing views! Fear of heights almost guaranteed.
      You can also create nice pictures from what you see, they tell so much more than “only” a map.

      I have “driven” the old (long) road from Frontera to Valverde on ground level tonight, just to see what it is like. Here is a view from it:

      • I.ve done several such journeys on the local buses (on Tenerife, La Gomera and GranCanaria) truly scary at times…Usually you can spot sections of the old road (pre tunnel) as you go; that’s even more scary… And that’s the way they will be evacuating… on buses, in a horking big hurry…

  8. People at Avcan /Facebook comment that the quakes they feel now are different than before the latest eruption, it feels more ‘dry thump’ (golpo seco) and like being out on the sea in a boat, people comment – people there ask wherter this might be related to magma being closer to the surface?

  9. Many thanks to Lughduniense for the link to the analysis data.

    Here is how it breaks out in KWare’s Magma program. (IUGS Igneous Rock Classification, Densities, and Viscosities)

    Negro1 – Bulk Density 2.735 kg/m³ – LiquidousTemp 1204°C
    Blanco1 – Bulk Density 2.339 kg/m³ – LiquidousTemp 1105°C
    Blanco2 – Bulk Density 2.399 kg/m³ – LiquidousTemp 1140°C
    Negro Hu – Bulk Density 3.122 kg/m³ – LiquidousTemp 1105°C
    Blanco Hu – Bulk Density 2.364 kg/m³ – LiquidousTemp 979°C

    • very cool that you delved so deeply into this Lurking. It is going down on my list of unattainable dreams to actually go to university with you to study this stuff.

      What’s fascinating here is the gap in the middle. How come no semi-evolved magmas? Only primitive and highly evolved .. I guess this reinforces the idea of sudden injections of primitive magmas from deeper mantle into pockets of long-repose magmas which have had time to evolve into the silica-rich end of the scale as posed in the abstract from Longpre, Troll, (troll?), et al. that Hattie posted this morning. Either the thing suddenly triggers an eruption, or it goes into slumber for a while until the next injection occurs.

      All well and good. But the where hell are these primitive magmas forming and why?

      • On thing that keeps springing to mind is that Jurassic sediment. That could be the source for the silica. It’s not that it has had quite some time to differentiate, but that there is a lot of pre-separated silica just sitting around waiting to be incorporated into the mix.

  10. The stain now seems to have moved further to the left again. As this is against the prevailing flow I am wondering if this is yet another vent.

    • What exactly did you see earlier, I was out putting the hens to bed. What I see now is nothing going on in the distance anymore and green stain starting at the harbour wall and going out some hundreds of metres. There are white streamers on the surface of the water aligned with the strong wind which suggests some sort of chemicals in the water to produce foam. Boiled seaweed perhaps. I assume there is a vent well to left of all the views, does anyone have hard information on this?

      • OK, I see that the streamers of foam emanate from the exposed rocks in the surf at the left hand end of the harbour wall so that means nothing. Greenish water now seems further out. Are we sure this is not a lighting effect at the end of the day?

      • The stain was spreading from the right hand of the picture (harbour wall cam) almost as far as the left of the picture, Previously I had only seen it spread as far left as just past the last dalek to the left. Earlier still I saw the stain develop into a ‘fizzing’ area but it didn’t last longer than a few minutes. Hope that helps. Info worth a few eggs? 😉

        • Just checked the cam again and realised the daleks have pretty lights on their heads. 😉 And I always thought that Daleks were unfriendly. 😦
          Too dark to see anything now so I look forward to seeing if there are any more developments tomorrow.

        • Hatching eggs or eating? We do occasionally ship hatching eggs but the only time we have shipped eggs for eating it has been goose eggs. Would you believe some of our goose eggs went via her son to an old lady in Iraq. We spent some time cleaning our fingerprints off the eggs in case the contents got replaced by explosives!

        • @eyeofskye. Haha you really made me laugh about cleaning of the fingerprints! 🙂
          We used to have hens for eggs when I was a kid but landlord here wont allow livestock. 😦

  11. There are busses arriving at La Restinga now as I can see on the Webcam. They get the people for the night perhaps. Or is it real evacuating again?

    • That assumes that one actually believe in magma chambers.

      I think the “chamber” idea to be questionable… much like the Easter bunny.

      Regions with an overall increase melt percentages yeah, I’ll buy that, and I would also tend to think in terms of a matrix of cracks and fissures that are filled with melt. But a chamber in a classical sense… with clearly defined walls. No.

      Along those same lines, rock melts at various temperatures. Take, for example, the solidus points for the material in the Restolingas (Bob’s Floaters)

      Negro1 1204°C, Blanco1 1105°C, Blanco2 1140°C, Negro Hu 1105°C, Blanco Hu 979°C

      In the area where Blaco Hu formed, Negro1, Blanco1, Blanco2 and Negro Hu would be solid rock. Likewise, in the region where Blanco1 and Negro Hu formed, Negro1 would be solid rock.

      This is because rock does not melt at a specific temperature, it goes through stages of melt with the constituents melting/solidifying at different rates depending on temperature/pressure and characteristics (solidous) of the minerals involved.

      This is how you can have different crystal structures that the geologists can analyze to determine what the conditions were when it formed. The longer you have a mass that sits, the longer the crystals have to grow larger. One thing that is apparent from the different papers, is that the material at depth tends to circulate and go through successive stages of growth. As a part of the mass becomes more differentiated and or denser, it settles out and drifts deeper in the more molten part of the mass.

      Fresh injection of magma from the mantle adds material, and heat, tending to keep the mass in motion.

      If the pressures become great enough, or the stress load changes enough, that part that is molted gets pushed up through fissures to an area with less pressure. If enough heat accumulates to make the new region cross into the liquid regions, the magma will site and differentiate there, percolating through the cracks that are present. If the overlying rock grows weak enough, or if there is enough of a push from magma below, it could eventually make it to the surface.

      It’s not really a matter of there being a “chamber” but more of a reservoir.

      (Note, in Spanish “Negro” = “Black”, “Blanco” = “White”)

      • Very nicely put. I always hated the way Hollywood/TV presents the idea of this giant underground cavern half filled with boiling lava. Looks good but so unlikely. Of course you can get small chambers close to the surface that empty if the pressure drops but anything of any size, at depth and with everything plasticized and fragmented is going to collapse smoothly if the magma drains away leaving no void.

  12. It seems I’ve missed a lot today. Below is a link to AVCAN facebook site which shows.. a map of the sea in front of restinga with 3 ‘bocas’ or mouths. Yesterday said there was more, then rushed to say not, thetn today this appears. It is all getting way to irksome. I think if I lived on El Hierro, I would have a major problem by now with eithr drink prozac valium or all three together.


    • Jenny that is a really interesting photo! They show the bocas/mouths a long way out to sea. Look closer to La Restinga though. Can you see the two round light coloured stains there? I think perhaps that is what we have been seeing today but they have vastly increased in activity because the stain was extremely widespread today and much, much closer to shore..

      • The only thing that saves the canaries and the people of the island of Hierro in particular, is his character. They are peaceful people and usually they have a great patience (“pachorra” it says here). But everything has a limit.

  13. It seems they open now the tunnel at certain times for car convoys which accompanied direction Frontera-Valverde at 6:30 and 7:00 in the morning, and in the evening at 19:00, 19:30, 20:00, 20:30 and 21:00. Direction Valverde-Frontera at 6:45 in the morning and in the evening at 19:15, 19:45, 20:15, 20:45 and 21:30. (from today’s Diario El Hierro). http://www.diarioelhierro.com/ (Title: “Se autoriza la apertura selectiva del túnel al inicio y final de la jornada laboral ” – Opening of the tunnel allowed at beginning and end of working day”)

    Is this now safer than the mountain road? Would perhaps confirm the information about the gas emissions. – Compare to gas emission map!

    I absolutely can’t understand why they don’t evacuate these poor people living under the siege of a volcano ….

  14. @ Ursula, (volcano cafe)thanks for deleting that bad link on the other thread, I will re post it again in the same place when I am somewhere with a connection thats better than 30kbps!

  15. Well thats two days wasted. Fortunately I spotted the error before it got posted. This was what I thought the data revealed:
    “””El Hierro: did a ‘silent slip’, not rising magma, trigger earthquake swarms
    The unusual time course of the GPS motion and the upper earthquake swarm raises the possibility that an aseismic ‘silent slip’ generated the activity at El Hierro. This hypothesis contrasts with the conventional interpretation that rising magma induced both the GPS motion and earthquakes.
    El Hierro – a temporal disconnect
    Between 10 July and 10 Oct the GPS stations at La Frontera and Sabinosa moved steadily north-eastwards by 40 mm. The swarm of ca 8000 small earthquakes began at the same time as the GPS signal but at alow rate compared with the final 14 days. The disconnect between motion and earthquakes was pronounced, as shown in Figure. Note that most of the GPS motion (80%, 32mm) had been completed when only 7% of the earthquake cumulative energy had been released.”
    In the figure I compared from 18 July to 10 Oct on identical time scales:
    – the energy curve:http://www.ign.es/ign/resources/volcanologia/jpg/energia_HIERRO.jpg
    – the Fron-IZAN GPS: http://www.ign.es/ign/resources/volcanologia/jpg/ELHIERRO_GPS_FRON-IZAN.jpg

    Its all utter rubbish.

    • Trick question?

      I would have to break out the other station to station vectors to figure this one out. It might be worth while to extract the N-S and E-W components to look at what it going on.

      The only quick guess I can give is that the base reference station might be in motion also. Does the motion reflect the over all movement of the African plate or it’s rotation?

      • No, no trick. All you need to find the cause of my erroneous line of thought is there, though not exactly in plain view. ( which is why I failed to spot it)

    • Hmmm…

      Because FRON-IZAN chart does not show movement of La Frontera, but just that FRON and IZAN stations are getting closer to each other?

      Because this is an IGN chart that shows only decrease in the (probably 2D) distance between FRON and IZAN and does not say anything about the respective directional movement of IZAN nor FRON (e.g. did either of them move N-S, E-W, up-down)? So you can’t say anything if there was actual uplift or not?

      Because you don’t know where IZAN station is?

        • Only thing I can see is that your dates are out. You say that ‘between 10th July and 10th Oct’ and then compare from 18th July – a few days of analysis out somewhere ?

        • Well maybe a shade out , but the error is really huge – it denies any possibility of what I thought was happening

    • Okay… on a limb here. I would think that as the GPS motion came to a halt, and rebounded in the other direction, that there would have been a concurrent increase in the quake signal. I don’t see that.

        • All of them do that, all of the IMO charts are stunted too.
          There is a mathematical reason for it, but it sadly always leave a hokey stick knee.
          What is important what happens after the knee. It is what happens after the knee that is important, and with that I mean the tell tale changes in the pattern.

        • The weird thing is the long flat part in the cumulative chart, it was a lot of small quakes, and pretty much no motion at all. Then there was a lot of quake energy and still no motion.
          I think Bob created a disconnect between pressure buildup, but the magmatic infiltration continued as an uplift disconnect. This was of coursed caused by the de-gassing of Bob relieving pressure en par with magma arrival.
          So then, back to the incoming eruption.
          But Peter, I still think your “slippery stones” oozing around down there has quite a lot of merrit.

        • oops – I see Ursula got it above. Didn’t think it looked right – couldn’t line up the dates properly. Still – may yet be able to make something of it !

    • Not really two days wasted. I’ll share what I found about ‘Silent slip’. Its a rather new discovery – its large scale GPS motion without earthquakes:
      Aseismic or Silent Slip
      There is evidence for large GPS motion unaccompanied by seismic signals.
      ‘ Aseismic slip’ was discovered ten years ago, originally in the Cascadia subduction zone.


      Roughly 20mm of GPS displacement occurred over an area 300km x 50km, but without earthquakes.

      Silent slip was reported in 2006 at an island volcano.
      Earthquakes triggered by silent slip events on Kilauea volcano, Hawaii


      Quote: “”Here we report on swarms of high-frequency earthquakes that accompany otherwise silent slips on Kilauea volcano, Hawaii. ….in January 2005, the slow slip began before the increase in seismicity. The temporal evolution of earthquakes is well explained by increased stressing caused by slow slip, implying that the earthquakes are triggered.” “…the cumulative moment of the 2005 earthquake swarm is…. far less than
      that of the slow slip,….”

      • And it is happening in the Dead zone in Iceland, 25 mm movement to the east, and 10 mm north every year, and not a single quake in a decade… And as far as anyone know, there has been not a quake there since Lakí went off. So, it has been a likely totall of 6,25m east and 2,5 north on average in an area the spanning from Katla to Vatnajökull.
        But there it is more of silent stretch, than silent slip.

    • I still think it has to do with the gas emissions. Depending on the map in Carl’s blog entry of today, there are no less than three places with more important and two more with not so important emissions in the vicinity of the mountain road from Frontera to Valverde.

      And then they think perhaps also about possible eruption vents opening near this route which seems to go up to around 1.200 m.

      Perhaps the Roques de Salmor stopped emitting gas.
      They intend to pass through only in accompanied (perhaps by Guardia Civil) convoy.
      And finally, it would take much less time to pass through the tunnel.

      • Did you see No. 5 in the conclusions how the magma chambers (sic) under Tenerife are posited to lie between 5 and 14 km? This would put them above the zone of the eq swarms were we to translate the whole shebang to El Hierro, i.e. the swarms would be indicative of the genesis of mafic melt which is only now infusing the fractionated pockets under the island… then taking the magma repose times from Stroncik we would have “weeks to months” before an eruption. I have the feeling this baby has only just started to rock. Bob might just be a sideshow, an aberration from a particularly accessible dike or something.

        (and no, I didn’t read the whole paper 😉 I bleeped over all the big words and cut straight to the chase!)

  16. Peter!
    A really good show there. That really showed how science should be done. I think you learned out more about scaling in plots and how easy one can make errors in one go than most universities can teach in a year. And also perhaps the most important thing in science, publish your no-gos. It saves a horkload of time for others by doing it. Sadly they do not give out Nobel prizes for publishing the no-gos.
    Really nice of you to show it! Cudos!

    “A brave man admits when he is wrong, a great teacher makes a lesson out of it.”

    “A theory that pewters out moves sciences forward as much as a functioning one.”

  17. Wow. This is so insane. The community here makes me feel slow and limited. What comes together in few hours is just crazy. No chance to offer the reading, the attention and the response many deserve for sharing so good thinking.
    Peter, respect. First for the thinking and then for the honesty. If there were more capable of this, we might have less trouble in many domains.
    Carl, by quick reading I notice trolls and scaremongers. Please give me the key to where you keep them. I need to release some energy. Or at least is there anything one could say to keep their heartbeat up? 🙂 Hey out there, 2012 is approaching… Mmmmmh…

    • Could’t agree more Geoloco. A great bit of honesty there by Peter. And it’s taught me to look more closely at the scaling. Why would they do that without flagging it up?

      And there probably will be a disaster in 2012. London are hosting the Olympics and we have a disaster-prone London Mayor in charge. Watch out for Boris. We scots will look on in awe. 😉

      • My impression after 2 weeks in Scotland and following the Swiss Highland Games championship: It will take more than the end of the world to trouble the scots… 🙂

        • And here my most honest compliment. After some travel experience I can happily look back, You Scottish people are the most polite and friendly I have ever met. In only two weeks I made several impressive experiences. No kidding, no sliming, just a fact from a single and subjective point of view.

        • Nonononono. One example. First day, save myself out of the town where Inlanded (hate it when too urban), after 2 hours of driving on the wrong side (:-)) I come to a parking lot and fight with the “money machine” (have only paper at this moment), behind me stands a local and asks “how long would you like to stay here?”, I “an hour or so to have my first cup of tea”, and the guys puts in a coin and says “welcome to Scotland”. That dude managed to shut me up. And it was not the only example. You guys really have impressed me.

        • Merlin, I lived in Scotland for 5 years when I was a youngster and the rest of my life in England and although I am English born I can honestly say the Scots were far more generous than any English man or woman I have ever met. They may be careful with their money but that is a positive trait especially these days but mean, never!!! Actually I have also found the Spanish people very generous and helpful too and in Norway we once had a lady driver on a bus, stop the bus and walk to the end of the road to show us the way to a campsite! Impressive and not a single passenger complained.
          Outstanding kindness and I have never forgotten it.

        • Gosh – thanks guys for putting paid to the stereotype. I like to think we’re ‘canny’ rather than mean 🙂 And to prove it , the first Sheepdips on me !

      • I came here to learn, boy is that working!

        I also realise more than ever now that a lot of you guys are so far ahead of me that you could be from another planet…..

        Full respect to Peter.

        • Kenpea, they are amazing aren’t they! But never forget so is EVERY human on this earth in one way or other. My kids are highly intelligent but I always reminded them when little that everyone is good at something and to look down on no-one. I must admit I am in awe of many on here though. 🙂

        • Geoloco, Haha, point taken, but they were kids and I was right in a way, politicians are good at being idiots and Trolls, well they aren’t really human are they? I expect mummy Troll loves them.

      • And now you heat me up even more? And you wonder that your comments are filtered? 🙂
        I shall beat them down in finest gladiator manner. You shall not know what to look at – sweat-shining muscular bodies or squirting blood… Ouahahahaaaaa!!!!

        • So, I have my leather hot pants on, lightly hairy chest oiled, Swiss army knife sharp as the edge of a liparian obsidian. Where are them 2012ers? WHERE??? Come on guys, Nibiru is a heap of poo!!! Want more???

        • Carl, I need a second personality in here. Something like Batman, you know, to hunt 2012ers at night. I would call this obscure part of me “Randy Dark”…
          Ok, ok, I come down. Don’t put me in jail next to the trolls. I heard say that they smell somehow…

    • wow, Peter, certainly no need for a red face here. It is science at its best and most of the rest of us are anyway struggling to keep up with the pace here. It is exhilirating! Keep more coming please!

      • Carl, thanks for that – not seen him speak before. Open Science has big barriers – it hits at the basic sociology of research. Competition is the driver. I think he knows it.
        “First is first, second is nowhere” – that has got to be a driver for those 70-hour weeks.
        Intellectual property rights- prior disclosure. Univs very keen on those.
        “Publish or perish” Journal peck order is very important in assessing individuals qualty re appointment/promotion/funding.
        ‘Impact factor’ of web contributions needs addressing, but that imples refreeing (anonymous) -goes against the spirit of the web.

        What I would like to see is all published work placed on web for free. With blog/comments section attached for each paper. No anonymity- but no refereeing either. So all papers open for free discussion. That would start the ball rolling. Publishers – apart from thsoe run by learned societies- would fight it to death- haha.

        • It is a lovely idea, but I think that Springer and the others would take out a hit on us… 🙂
          Peer review by mass attack? Hm, might work, I still think it would be fairly close to normal peer review since most would be collegues still. But it would draw in quite a few and raise awarenes of science in quite a few.

    • You studied under this guy? Wow. That’s serendipity for you. He’s great isn’t he? No wonder you started this blog. This place is a perfect example of what he is talking about it. Kudos to you Dr. Strange. Now, where’s my sheep.

      • To be honest, Fredkin has higher stumpyfying factor 😉

        Alan has a bottle of Sheep Dip over at the Sheepy Dalek Bar for you.

    • Waoh!

      Finally, I found some scientific reasons why I have been spending a lot of my freetime on Wikipedia and such! 🙂

      Especially interesting and a “must have seen and discussed” for schools and all higher education!

    • Wow!

      Finally, I found some scientific reasons for why I have been spending a lot of my freetime on Wikipedia and such! 🙂

      Especially interesting and a “must have seen and discussed” for schools and all higher education!

  18. Third attempt: colour coding changed & INVOLCAN added to the list of relevant authorities following feedback from Carl & Ursula:

    • Interesting how the reds and yellows make a pattern. Especially that red/yellow lump on the backside. Odd slanting of it, looking like a massive chute running up to Los Llanillos if I understood it correctly. Also a pattern that seemed to be running out a way into El Golfo.
      But I might be wrong since I haven’t gotten used yet to your plots yet.

    • The only real pattern I could see is:
      – mainly smaller quakes in the central blob – which could mean hotter / more ductile rock so less fracturing;
      – the larger quakes occur to the NNW and SSE of the central blob- which could mean / cooler or tougher rock to fracture at the sides of the central blob;
      -a few, usually smaller quakes above the 8km level – one cluster must be in the vacinity of Bob. But still no clear routes linking to the larger clusters below.

      My own interpretation of the EQs was that the central blob was near the top of the magma reservoir and the side shoots were possibly dyke intrusions. But there do seem to be chutes running through the blobs.

      Now we have GeoLurking’s great plots of P & S waves which seem to show a lot more above the 8km than the EQs are showing – some of that rock must be ductile.

  19. This is… sort of stupid… but it looked interesting so I thought I would share.

    I have been working through the trig that is needed to determine the straight line distance from seismic stations to the hypocentral quake locations. For those that don’t know, an epicenter is where in latitude and longitude a quake is at, the hypocenter is the quake location plus depth. What you are talking about a quake and you are using depth, you are actually talking about the hypocenter, though we call it an epicenter.

    But that is just terminology.

    When a quake occurs, the energy from it travels outward in a straight line path. Sure there will be reflections off if other rock masses, such as occurred in Christchurch, and likely occurred in the New Madrid 1811 quakes off of emplaced plutons. It will also refract as it passes through rock of different densities. When trying to work with this, it gets to be a pain in the ass really fast. So, a lot of times refraction effects are thrown out for the sake of simplicity.

    That’s the case here. I’m just trying to glean some meaning from data using whatever resources I have and a somewhat limited understanding of the physics.

    In my quest to pull meaningful data, I needed to account for the spatial orientation of the quake source, and the station locations. I’ve mentioned time and time again, that quakes near the epicenter are slower than the quakes down range. Part of it is physics, part of it is trignometry.

    When a quake occurs, the energy has to climb several kilometers to get to the closest station.

    For example, if a quake occurs at 20 km depth, and the closest station is only 3.3 km from the epicenter, a trip time of 5.85 seconds works out to a speed of about 0.69 km/s. For an S-wave, that’s really slow.

    In actuality, the energy from that quake went through a distance of 20.275 km when you slug through the math of finding the direct path distance. This involves a combination of finding the chord length of that slice of earth finding the height of the chord, getting the difference of that and the quake depth and then solving a right triangle. It’s just trig, but it’s still a pain in the arse.

    Doing the speed calculations off of that you get an S-wave speed of 3.47 km/s. A value much more in keeping with known S-wave speeds. That is something we can work with, there is real data in that speed since we have eliminated the vagaries of how everything sits… spatially.

    I took that formula, in spreadsheet form, and ran it against about 240 individual quake arrivals at the stations in the Canaries, with several samples from all over the place. No spot in particular was examined, but the quakes under El Hierro contributed about 95% of the arrivals.

    Because of that, I think I should put this out.

    First… this IS NOT TOMOGRAPHY. It’s just an identification of areas were the wave speeds were either slower or faster than other areas. There is a lot of additional things that need to be done to make this a half assed valid look at El Hierro. But for a preliminary look… it shows promise.

    The distance is the distance from the quake. No specific quake or spot was used, so it’s not valid to look at it with that perspective. There is a lot of pollution in the data from quakes that were not under El Hierro. El Hierro quakes dominated the data set, but even those were spread out north and south of the island.

    What it means.

    Wave speed is directly affected by the makeup of the rock. It is also affected by the temperature of the rock. Slow areas tend to indicate more loosely consolidated material, or hotter rock. This is particularly true of S-waves. S-waves can not move through a pure liquid.

    Improvements that can be made.

    1) Localize the data by lat-lon postions. That way specific areas can be looked at.
    2) Incorporate the sediment layers and see if their effect can be see and/or accounted for.
    3) Add a lot more data.

    Again… this is NOT tomography. It’s just an interesting plot.

    • You’re right; it is a really interesting plot. Suspect that the sediment layers may be contributing to the spread at the top of the plot as the sedimentary layer starts at around 8km?

      • Something like that. I have to go back into the papers to get a feel for that.

        My intentions are to eventually try and back out the sediment’s contribution or to at least be able to identify it. It’s probably gonna have a reasonably smooth contribution that can be compensated for as a function of distance from the epicenter.

        The part that perked my ears up was that slow region dropping to greater depth. Given the spread of the quakes that I used, many of them would have passed through a center “pipe” if there was one.

        That’s one of the reasons I’m gonna keep poking at this.

        • You are really starting to go orders of magnitude beyond in your plotting now.
          For the rest, this is a first really. Yes it has been done a few times with bucketloads of equipment and much higher resolution of the original data.
          This was a really bright version of doing it.

          2 questions, what would happen if you did the same adapted for the p-waves? And then, what would happen if you took the P-wave sheet, overlayed it ontop of the S-wave, and did an average of sum per pixel (merge)?
          Might though be a stupid idea…

    • You know… This would be a good post. It is rather ingenious, and it is what IGN should be doing instead of running around being Politicos. After all, it is a map of sorts of the innards of El Hierro. And we are not that spoilt by those…
      Would it be okay if I posted it so it wont get missed by people?

      • As long as you pointed out that the resolution is crap. It was a proof of concept. There is a lot of dirt (data) that is out of place in it and not aligned with where it should be at.

        For one, there are quakes on both sides of what may or may not be a slow are column, as well as an artifact off to one side that may not be a second slow area.

        Not to mention that the seismic stations are all around it also.

        I have to work that out yet.

        I’m thinking that if I select quakes on one specific side, and seismic stations on the other, I might be able to get a cross section of what ever is down there.

        Might work, might not.

        • You decide when. I just liked your explanation in it and was thinking about posting it all, not only the plot. But if you are going to do an uphotted version perhaps it should be posted together with the first to show the progress of your work.

          Now, I need to shleep.
          Vi ses!

      • P-waves are just as easy to do… in fact, they are just a selection away in this data. The problem is I have to manually extract the data from the phase reports on a quake by quake basis.. and that is sloooooooow.

        Another tactic that I may be able to use, is to look at the differences and the changes in the differences in P-wave vs S-wave speeds. That might also be enlightening.

        • Ok as a non volcanologist trying to interpret the plot – do the different seismos distances to the different quakes balance out (on average) ?
          Could one take the ‘average’ central spot placed between all the seismographs as the starting point for reading the distance to the epicentre on this plot?

          And if so could you read the plot as saying that within 20km of that spot there is a slow region up to a 16km depth.
          And might one infer that the ‘deeper tube’ would be at a distance of 10km from that point – or is that just me looking at the plot and reading things into it that are not there?

  20. Well, I’m obviously up later than most on school nights; just caught up…I think I mentioned that I know a bit about a lot of things. I’ve been harking back to my days of studying anatomy and physiology (I was briefly a student nurse…) The A&P bible for nurses was Tortora, there were tracing paper overlays so one could see how everything fitted together (bibliophile too, does anyone else remember actual books?)
    So, to get to the point does anyone know a way to overlay the various maps (I like maps n’ cartography n’ that…) “interactively.” For example; layering the Tanganasoga (I’ll learn to spell that eventually) uplift plot (Lurking’s, great) over the (hi-res geological map posted earlier) over the gravimetric survey of 2006 (done with the £100000 gizmo) over the EQ plot for !!/!!/!! etc.
    So I suppose the way to do it (and I’m not trying to teach anyones Grandma to suck eggs x)is a folder containing all the available maps and then select those that you want to “layer.” They would all need to be to the same scale and “overheads”; but I’m sure that’s easy enough for the Jedis (Jedies? What is the plural of Jedi?)among us (Star Wars too…)

    • I’ve done it with Google Earth. In that you can adjust the transparency of individual overlays.

      You just have to tweak the overlay to make sure it lines up with known features and has the right projection.

    • Sadly I am a codiot so I cannot really help you there…
      Now I see elderly women with straw-hats wandering around at a garden party drinking eggyolks with straws.

    • Without the Bullhork.

      Does anyone know a way to overlay the various maps “interactively.” For example: layering the Tanganasoga uplift plot over the hi-res geological map over the gravimetric survey of 2006) over the EQ plot for !!/!!/!! etc.
      So; a folder containing all the available maps and then select those that you want to “layer.” They would all need to be to the same scale and “overheads.”

      • Well, you know, there are a lot of people putting in a lot of effort and thought into various things here. Some come here to have a bit of learned discussions, some come here to learn, some come here to get news, well, the reasons are probably as many as there are commenters and posters in here.
        But one thing we have in common, we do like our Bullhorking. And most of the time we do remember to answer any and all questions. It might though take a bit of time untill someone with a good answer logs in.
        So, just relax… (And no, I do not have the answer for you, not my field)

        • I guess Betty is right.

          Somehow it’s frustrating to see how fast thoughts go in here. What can “sparcely in-peerers” contribute? It’s not a 5 minutes matter to keep up with and give valuable input to the main commenters. It makes me feel the only role left is somehow the one of a kind of “cheerleader” to kepp the fire of our shining athletes burnint tremendously hot… Well and maybe sometimes I could get some 2012scaretrollers to turn myself into Randy Dark and finally make a first use of my all new XXLmegaT&F2011Carbontitaniumcoated automatic taring & feathering device. I had 3 month of intensive work-out with Carl’s lightweight and noiseless fitness machines to be able to carry it. But now, beware… Sorry, again. Hard day ahead…

          Good morning, relax and enjoy life whatever may come.

        • @ Geo Loco The poet Milton wrote, “They also serve who only stand and wait.” “Meaning: We all have a place in this world and we all perform a function, regardless of our ability or disability. The audience is what makes the players perform well in a play.

        • Thanks Betty and Lurking that’s exactly what I’m talking about. I’ll have a noodle around and let you know…May take a while…

      • You need GIS software for overlays.
        ArcGIS by ESRI is the standard one, but costs a lot of $$$$:
        Quantum GIS is a free & open source one, but it does not have as much fucntionality as ArcGIS:

        Neither of these does 3D though (so you can’t put stuff on top of Lurking’s or Karen’s depth plots). For that, Matlab is an option, but again, that costs $$$.
        Or Voxler – volume visualisation software for Geologists (not free, but not as expensive as ArcGIS or Matlab):

      • That method of display would be terrific – and if it were animated we could events developing. has to be in 3D too, becausee its easy to forget that only about 5% of Hierros erupted mass is above sea level.
        But I have no expertise – only very basic PhotoshopElements. Thats enough to put two or three layers. But I dont know if the full Pshop allows layers to be made transparent under control of keyboard. And it would not be 3D. I suppose sections at 1km depth intervals could be made in P’shop, but a lot of effort needed I think.

    • Hi Ken,
      I’ve had problems connecting until a moment ago…. just managed to slide in to the EQ 3in 1 site. Looking very ‘green’ out there.

        • Joke Volta has said this morning that there is lots of colour, but no specific vent. Maybe just yesterday’s outpourings being circulated around the harbour.

  21. Something showed up on the Chie charts at about 6.17 this morning. It’s not on the IGN earthquake list and it didn’t register at Egom. Any ideas?

  22. Well.. I don’t know what sort of games TinyPic is playing. Every time I push the third (and most interesting) image to the reprobats they give me a link to some sort of whizz bang class room sort of place with some sort of anime garbage on the wall.

    So.. until they get their shit in one sock, I no longer recommend them to anybody. I just busted my ass over 3 hours of data and I’m tired. (and irritable)

    So.. the most interesting image is gonna go to Carl via E-mail.

    First, the slice of pie. Everybody likes pie.

    Along this wedge, is the area that is looked at in the attached plot, and the one being sent to Carl via E-mail.

    Remember, this is NOT TOMOGRAPHY. It’s a plot of wave speed. I chose a set of about six quakes that would give me a look at the speed patterns in that slice… hopefully across the area of interest.

    This might be the area driving the deep quakes.. might not be. It’s only a clue to the make up of the “stuff” at depth. The areas along the perimeter of the plot are where the reliability goes to shit… if you can call it reliable. My station error is on the order of a couple hundred meters, the quake average postion is the starting point.. and that has about 1.5 to 3 km of slop in it. Not te mention that the quake positions themselves have anywhere between 3 to 8 km of slop.

    It’s a very very rough look at what is down there.

    The more interesting S-Wave plot is going to Carl via E-mail… I cant’ help that TinyPic decided to be shitbirds at 4 am.

    • The second plot looks great – well the plot is great, but the fact that there is some very hot rock down there might not be so good.

      But I cannot get the first one – or all I get is a black screen.

  23. In general… the earlier plot was just a proof of concept and doesn’t really represent much. The stations and quakes were scattered all over the Canaries.

    The one I just put up is aimed specifically at looking at the pie slice. I picked about 6 to 7 quakes and stations where the waves would pass through the area of interest.

    The idea is that very hot rock… say, high melt percentage rock, will have a slower propagation speed to the quake waves passing through it.

    In other words, it’s where a magmatic rich region may be at.

    As I have stated, it’s not tomography… but it uses similar principles.

    • sure, I know you “just plot stuff” and this is all very new and unrefined so no one making decisions should use this (caveat talk to ‘proper volcanologists’ etc etc) – but when we look at the plot – which way around through the slice would we look at this plot ?
      is 0 distance at the quake end of that slice, or at the seismo end of it – or doesn’t it work like that ?

    • Does your analysis say anything about that ca 2km thick asesimic layer just above the deep eq focus? One possibility is that it is ‘underplated’ layer ie magma that has frozen under the lower bound of the crust rather than erupting and freezing.

  24. If (and that’s a big IF!) I’ve got my head around this, it shows that the magma starts off at around 12km distance and a depth of 25.5km, is split into 2 parts and is currently at around 21km depth at distances of 6km and 10km as marked on the “pie”.

    mmmmmmm pie……

    • @kenpea I think you read it correctly – @Lurking I wonder if it is possible to plot the same area ( same data set?) – and cover all the ground from that depth to the surface ? to see if that shows any sign of the sedimentary layer, or possible melt paths. ?

  25. @ Geo Loco. As I am in the middle of exams at the moment and should not be online at all, the most I can contribute right now to the organic, deep scientific thought here, are the words DOOM, DOOM, DOOM, DOOM, DOOOM,DOOOOOM. I hope they keep you happy and occupied for a while! 😉

    • Please remember there are folks from El Hierro likely reading this. While we are interested and excited by developments we don’t wish doom on anyone or wish to spread panic.

      • Neither do I, and I apologise if I’ve done wrong, but I’m just pointing out what seems fairly obvious to anyone looking at Lurking’s plot.
        If I’m wrong in my understanding of it, please put me right.

      • Mixed signal here, just to make it very clear, I do not wish doom on anyone especailly the islanders, as one can see from previous posts of mine. By the way did you see the interesting link I left on Scotlsh island traditions earlier?

        • PS. Just to make it very clear to any people from El Hierro, my original post was NOT a comment on any graphs or plots etc regarding the islands present situation but a tongue in cheek (light hearted)reply to an earlier post regarding 2012ers and letting people know that once my final exams are finished, as a newer poster here I hope to be able to contribute more to the more scientific debate on the blog. Apologies as I thought it was going to appear under the post I refered to and not by itself at the end. I really to need to get a retinal implant.

        • It’s OK it was just intended as a gentle reminder. I’ve pulled back on several comments I wanted to make in case I caused a problem as well.
          Missed the Scottish traditions. I shall go and have a hunt (was that one of them).

        • Thanks, it is good to get gentle reminders, the post was on the tradition of swimming catlle and sheep etc between islands as they used to do nearby. I posted it after a more serious post on how to keep your pets safe in potentially difficult situations and how having them around can help with stressful situations especially for younger children

      • I totally get what you are saying, but that also can be said of the authorities who appear to be withholding info, or are just not saying as much as they know or speculate. That’s their problem, I suppose, what to say to their people. But you can’t have it both ways. Either you suck it up and say what you really, really think, or you sugar coat it and hold back. Not saying that the Krakatou scenario is acceptable to speculate on (just an example), but if you have plausible data, then, what’s the policy? Speak up and tell the people what you have, or take a step back and wait and watch. Ouch!

        That “spreading of panic” can also be motivating people to help themselves and prepare for a possibility of a very real problem that could soon be in their laps. I personally would want to know the data and what it would mean to my family. All that matters in life are relationships and your personal bonds. You have to have Plan A, and Plan B.

        There is absolutely no reason to believe that the offshore eruptions will stay offshore.

        I think you are sweet to care for the people. You’d be the guy with his sleeves rolled up.

        • Betty, I did not really get who you aimed this one too, but I will answer a bit here.
          The policy of what is released here, or not, in the posts are my responsibility, or someone I appoint to do so. If I am not around, then that is Ursulas responsibility. In the posts I have written I have had sources with insight into the workings in the agencies monitoring the events at El Hierro. I cannot, and will not write those reports ad verbatim, then I could be giving sources away.
          What people write in the comments is up to them. If I or Ursula deem a comment to violate the quite simple rules that apply in here, then we will remove it.
          What people write, and what limitations they set on themselves, is quite up to them.
          I am happy as long as people hold a civil tone in here.

        • I was talking to EyeofSkye. My comments regarding “what do you say” was a discussion about what the authorities should do…if I did not make this clear, then my writing was poor, and I apologize. I will certainly say WHATEVER I feel, and trust that you will edit what you want, although I HATE having my posts edited (which has not happened here.)
          I appreciate your comments, Carl…the software does not always allow us to place the comments exactly where we want to put them in response.

        • Not my dog, not my fight.

          (Michael Vick be damned either way, I like dogs and he is a hosebag.)


          “Either you suck it up and say what you really, really think, or you sugar coat it and hold back. Not saying that the Krakatou scenario is acceptable to speculate on (just an example), but if you have plausible data, then, what’s the policy? Speak up and tell the people what you have, or take a step back and wait and watch. Ouch!”

          In a way, I agree. But in my case I emphatically point out that my opinion is not a trained, taught, or learned opinion. I think that is very important. What I state could be completely wrong and I don’t want someone freaking out because I say something not quite in keeping with the way things are perceived just because I can look through some data and see what’s not being said.

          Just because I can, it doesn’t mean I’m correct.

          People come through these blogs all the time looking for confirmation of bad stuff that they have heard. Personally, I’m not gonna play into that if I can avoid it. But I will tell them what the data seems to say, as long as they understand that I am not the authority on the subject.

          Well, I think I have intruded into someone else’s conversation enough.


        • GeoLurking, I appreciate your comments. I don’t advocate scaring people. People can think for themselves. If they come to this blog looking for professional opinions on what they should do, they won’t find them, as that is made abundantly clear in the caveats all around the opinions. This is an over-the-fence-between-neighbors discussion on the birth of a volcano, nothing more.

  26. It’s a pretty cool graph to actually come out showing that quite so graphically. I wonder if there is some way of quantifying the signal to return some kind of percentage figure to give us some idea of how much melt there is down there but I imagine the error involved would neuter any informative value… pretty damn cool nevertheless.
    re.. the doom and gloom. The fact that melt is down there at that depth and that location is not anything particularly new. Combining the eq swarms, the vent (Bob), the inflation and the gas readings, we already know there is magma on the move down there, so the warnings for the population from this new graph haven’t actually changed much (in my opinion). Remember, Lurking’s graph starts at some depth.. the path that the magma then takes to the surface is a total unknown, if it even does erupt. What is particularly cool is that his chart confirms what we already suspected.
    Also the papers on the petrology of the island (particularly the abstract posted by Hattie yesterday) point to repeated magma mixing (up to five or six cycles in some cases) suggesting that this type of event occurs more frequently than an actual eruption, so we still have no idea whether this is going to end up in another vent on land, continued activity at Bob, or even cessation of all activity.
    Caution is definitely called for, but it is still very hard to know what is going happen next.

    • I’m toying around with idea of putting the data into a vice

      On Carls harmonic waveform inerferance shapes that I ran across in Iceland, one thing I tried in the weeks after that, was to take the the quake positons and to rotate a the ones on the Reykjavik ridge so that I could plot them in a linear fashion. It was messy, but it worked.

      My idea is to take one well used station… probably CHIE, and to organize the quakes around that station. In doing so, I might be able to use CHIE as a sounding stations and look at individual bearing cuts from/to it. I wouldn’t actually be plotting the quake data with it (that’s where the mess came from) but would use it to select candidate quakes.

      I would still have to hand code them into the database. (well, partly hand code)

      I just wish there was a way of reducing the quake position errors. Gonna have to think about that.

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