El Hierro – What did Elvis have to do with the Island?

Photograph by unknown. Orchilla Lighthouse, famous for being “The end of the World”.

During the night life got fairly interesting in El Hierro as the residents woke up from no less than two earthquakes above 4M. The larger of these two reached 4.4M.

Otherwise it seems like the magma continues to move in a general southwesterly direction. This has had as an effect that many of the GPS stations on the island is registering a downfall. It is at the moment uncertain where the magma is going.

The activity that we have seen during the last weak and a half is a sill intrusion, or a horizontal oblong shaped flat intrusion between different layers of rock. The intrusion has happened at great depth, around 20 kilometers deep. The activity started roughly under the old volcano of Tanganasoga, and then progressed towards the south east, passing the famous lighthouse of Las Orchillas on the way. The lighthouse is famous for being called “The End of the World”, a strangely fitting denominator when taking the current activity into account.

If we look closer at the 4.4M earthquake it had some rather intriguing features. It had a very weak transient in the beginning. The transient is the initial earthquake that is starting the rift of the fault plane, it was around 1.9M in this initial phase. After that a heavy magmatic component started as magma gushed in to fill the void left by the earthquake, and as the magma entered it further delaminated the layers in the rock, and more magma flooded in and so on and so forth. Let us just say that it was a lot of magma moving very rapidly.

Image by IGN. The earthquake starts at roughly 41 minutes, and it continued for 6 minutes before ending.

The angle was also rather interesting. The fault plane was tilted at 134 degrees, so the propagation of the earthquakes fault plane was going upwards at an angle. This gave the earthquake a fairly hard profile to plot, and both location and depth was changed due to this. Initial depth was set at 12 kilometers, as that was the end point of the faulting, but the beginning of the faulting was at 21 kilometers. And at an angle of 134 degrees this makes the start and finish line of the earthquake being somewhat different in location.

The earthquake was both Long Period, and a of the Broadband type. What I like to call a wet earthquake as oposing the dry earthquake that is associated with tectonic movement. It also look quite a bit like the sonic signature of water moving unexpectedly in a tube.

Worried in El Hierro?

The activity is right now inconclusive. The activity has started to show higher up, but the bulk of the earthquakes is still deep down. So it is fairly impossible to say where an eruption might occur. Some believe that it will happen in the western part of the island, or out at sea south to southwest of the lighthouse. Some believe it will in the end be an eruption closer to land from the vent called Bob, or even on land close to La Restinga.

In the end it is more likely that we will have another Effusive Lava Vent In the Sea, or to put it in short, another ELVIS.

If you are feeling really worried, or things get worse you should read the splendid article on volcano preparedness written by our resident Icelander. More volcano wisdom in that article than anywhere else, a wisdom coming out of extended experience of volcanic eruptions.

https://volcanocafe.wordpress.com/2012/06/29/icelanders-do-prepare-for-eruptions-a-personal-observation/

I would also recommend that if you feel the need to relocate yourself quickly, go to the eastern part of the Island. It should be fairly safe since there has been no activity there. In the light of things, if you are really worried, or things heat up even more, do not wait for an official call for evacuation. Just go if you can or feel the need. Remember that in the end it is you who are responsible for your decisions regarding you and your loved ones.

CARL

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989 thoughts on “El Hierro – What did Elvis have to do with the Island?

  1. And just since I had Icecream today and GeoLoco is GeoLoco.
    For the fans of alternate Browsers:

  2. Hope its allright to post these quakes a little proud of myself that I actually noticed something was stiring I am learning well (I hope) !!

    2012-07-05 17:41:39.51hr 28min ago 27.71 N 18.16 W 20 ML 2.7 CANARY ISLANDS, SPAIN REGION

    2012-07-05 18:05:17.61hr 06min ago 27.71 N 18.15 W 21 ML 2.6 CANARY ISLANDS, SPAIN REGION

    ign.es

    • I’m just being in the middle of a fattest thunderstorm with high electric activity. And looks as if it will go on the whole night through. Some regions here are for sure having flooding and spontaneous slides. The regional news will be full of it tomorrow.

  3. The UK is on warning again for flooding and heavy rain apparantly all the bad weather is coming up from France.

    • Yup! The Eurozone likes to share with us !

      In Northwest UK we have an Amber alert for torrential rain tomorrow. My poor Husband still has to walk round delivering the post in it. When it is heavy rain like this he has many complaints from people who phone his sorting office complaining their mail is wet !

      • Nice one sativacyborg, that’s a very cool resource… I’ve been playing with a “fake 3D” plot macro for excel… I haven’t come up with anything totally satisfactory yet, may be a bit of a dead end. It does let me have a look at the wad for myself though, which is useful for “mentally modelling” El Hierro 🙂

  4. For Carl and those who have the ability to dig in these publications….

    This might be of interest if you can find it.

    Magnetic imaging of the feeding system of oceanic volcanic islands: El Hierro (Canary Islands)

    Isabel Blanco-Montenegro,
    Iacopo Nicolosi,
    Alessandro Pignatelli,
    Massimo Chiappini

    Article first published online: 12 FEB 2008

    DOI: 10.1111/j.1365-246X.2008.03723.x

    Issue
    Geophysical Journal International

    Volume 173, Issue 1, pages 339–350, April 2008

    • El Hierro is the youngest of the Canary Islands, a volcanic archipelago in the central Atlantic, near the African coast. The subaerial part of the island shows a characteristic shape with three convergent ridge that have been interpreted as a triple-arm rift system. These ridges are separated by wide, horseshoe embayments, related with the occurrence of at least four giant landslides. Recent works based on highresolution bathymetry, however, have shown that in the submarine portion of the island the rift structure is much more complex. We have analyzed an aeromagnetic anomaly dataset acquired in 1993 by the Spanish Instituto Geogrfico Nacional in order to obtain a structural model of the island from a magnetic point of view. A digital elevation model of the volcanic edifice was divided into a mesh of prismatic cells, each of them with its top corresponding to the topographic height (or bathymetric depth, in the marine area) and its bottom at the constant depth of 4000 m below the sea level. A threedimensional (3D) inversion algorithm was applied to the magnetic anomaly data that has provided us with a magnetization distribution containing valuable information about the inner structure of the island.

      We have completed the study with a forward modelling along some representative profiles. The magnetic model has allowed us to obtain new evidences about the rift structure of El Hierro. In particular, high magnetization values have been interpreted as intrusion complexes on which rifts zones are rooted. Their location confirms the hypothesis of a complex rift structure in the marine area, suggesting that sometimes rift axes might be shifted with respect to previous interpretations. In addition, the areas affected by giant collapses are characterized by very low magnetization values, showing that magnetic anomalies can provide fresh information about this kind of catastrophic event.

      • Its a paywall. Like Elsivieirioeioreoei

        The scalp papers to people.

        Some one in the geology field or academia might be able to get a hold of it and glean something usable to us.

        • I should have it soon. I wont have time to read and summarise it myself but if anyone would like to take on the task pls say so and I can arrange to forward it.

        • El Hierro is certainly complex. As time goes on and the more I read, the more complex it seems to be. No wonder nobody is really sure as to what is happening. All I can compare it to are some of the “smaller” volcanoes in the dead Zone in Iceland but like Iceland the Canaries seem to be unique in structure and difficult to compare with anywhere. I wonder if the Cape Verde islands are very similar. 💡
          Fogo is another volcanic Island formed over a hot spot
          http://hvo.wr.usgs.gov/volcanowatch/archive/1995/95_04_21.html

          I looked and eventually found this very useful paper. Useful in as much as it gives a clear description on the formation and the structure of Hot Spot shield volcanoes. It goes on to study in detail the volcanic system of Reunion.
          http://webdoc.sub.gwdg.de/diss/2008/letourneur/letourneur.pdf

          After reading up on various other Hot Spot islands the common factor in all these islands are that the volcanoes are all different in their plumbing!!!! Not very enlightening except it does explain why we have no idea what is happening and that for everyone with interests in El Hierro this is a giant learning curve.

      • This one I mean: Magnetic imaging of the feeding system of oceanic volcanic islands: El Hierro (Canary Islands).

        Geophysical Journal International
        Volume 173, Issue 1, pages 339–350, April 2008

  5. How about that…

    Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption

    Troll et al. Solid Earth, 3, 97–110, 2012 http://www.solid-earth.net/3/97/2012/

    (You have to love the author name!)

    http://www.earth-prints.org/bitstream/2122/7909/1/Troll%20et%20al%202012.PDF

    …We have analysed the textures and compositions of representative “restingolites” and compared the results to previous work on similar rocks found in the Canary Islands. Based on their high-silica content, the lack of igneous trace element signatures, the presence of remnant quartz crystals, jasper fragments and carbonate as well as wollastonite (derived from thermal overprint of carbonate) and their relatively high oxygen isotope values, we conclude that “restingolites” are in fact xenoliths from pre-island sedimentary layers that were picked up and heated by the ascending magma, causing them to partially melt and vesiculate…

    • was only reading about that the other day, I get interrupted and then forget.
      I EQ of 3.1 — 03:50:44 27.6896 -18.1590 21 — mbLg SW FRONTERA.IHI [+]
      in an otherwise quiet night

    • I like the comment from the above article,
      The occurrence of “restingolites” indicates that crustal recycling is a relevant process in ocean islands, too, but does not herald the arrival of potentially explosive high-silica magma in the active plumbing system beneath El Hierro.

  6. aeromagnetic anomaly on Tenerife being younger to the western side, also give us a clew to El Hierro’s move towards the west, because the initial EQ last and this year where to the west

    • Mötley Crüe has Chickens?

      Wow, loose the peak of your rock career and you start raising livestock. Brutal, but more self sufficient.

      • chooks lay eggs, not at the moment so, plus I have some fancy ones, Silkies(chooks) when I got the roosters and put them in another cage and my Bichon Frise(dogs) where running around, the little roosters got all excited thinking they where chooks( white and fluffy), hillarious

  7. Morning ppl!
    Interesting comment regarding “resingolitas”.
    What if in fact all this Hierro event (starting with 2011) is just another warm up for a future (I mean fuuuuture) flank colapse?
    I consider that under the island core the magma chambers start to enlarge in a lenticular way. This can be seen in all quakes chart. And that’s where the sedimentary materials come from.
    That’s why whole movement stays there about to 20km and goes just east-west or north-south.
    Of course there is Bob and countless Elvis (Lomo Negro was just one of the “king” of them) but in the end everything will go toward a flank colapse. This Orchilla lighthouse.flank I suppose that could be a good qualified area for colapse.
    Of course we witnesing maybe what mother nature always did in this corner of the world.
    But what about if this process is not so slow??? What did hapend thounsand of years ago we just canno’t compute in phases and time line, we just read a fact.
    Him…maybe I’m wrong…

  8. Bruce and Geoloco were right (and the Mayans): at this pace magma should reach Brazilian coasts in December, 21, 2012, bringing the torch for the next Olympic games. Brrrr! 🙂

  9. HI all. Just an information to all owners of sites with very odd names. If you set a trackback and we cannot figure out from which site it comes from and check the sites content, we will trash the trackback.

    • Hi Diana, happens sometimes, you can check Gomera or La Palma to see if anything major is going on, they do pick it up, Elvis just can’t make up his mind, so I am off, I am so tired, BBGN

  10. As long as almost nothing is up, at least here, maybe someone ( Alan) wants to check my new SEM images i did yesterday. A cooworker brought a pebble from the cliffs of Dover and i scratched some stuff off and placed it in our SEM.

    chalkstoneC12

    I also added some gem photos. One of them is a sapphire which i got as a present for doing the other images 🙂
    ( Better descriptions will follow later, i am working at them atm.

    • Interesting. It looks like fossilized tiny creatures (the light particles) that accumulated as sediments over time, and then «mineralized». As for the dark contents, I have no idea of what it can be. My guess, as a stranger to the field.

      • Oh and there is o dark content, thats the normal background. You fix the ashes or sand or… on the sample-holder with a tape which is sticky on both sides and black.

        • Good thing I did not spend too much time trying to figure out the dark “sticky tape” ! (smiley)

    • Thanks Birgit,
      Was it an actual piece of chalk or scrapings from the outside of a flint?
      Very interesting pictures and close to home, it’s all chalk downland around here…

      • That would be cool Sissel, and Schteve, it was a pebble one of those on the beachimages which was done by Karl not by me. He brought another stone too, one of those typical stones in the south of England. Lighter on the outside and if you break it apart, darkgrey and the same structure as Obsidian. I have no cue what they are, but i had no hammer, so i could not break pieces off. With the chalk, you could scratch stuff off with your fingernail.
        Maggiemom and Summer: I am hoping on Alan to tell me what we see. I think it are marine creatures, lets just wait as what our evil henmaster dresses up next time he is on.

        • Birgit
          I’ve never seen a SEM micrograph of flint! Mind how you chip a piece off tho’ very brittle!
          You’ve seen pictures of the White Cliffs of Dover, well all the chalk is made of those coccoliths – calcareous plankton

          • The beach where I live is full of flint, I once found a lovely shepherds crown made of flint. Also many of the flint stones have holes with a crystal lining. Not sure how they would have formed, and some have fossil holes, the indentation in a shape of a sea shell. ODD. I always thought flint was quite closely related to Agate. Am I wrong? We also occasionally get some lovely flints with red markings in them. Would be beautiful for polishing but take forever to polish off the outer ‘skin’. I have a huge flint in the garden with holes large enough to plant small alpines in, really pretty.

          • @ Sissel Silex
            Jasper/agate marketed as what they are, flint not used, doesn’t polish too well cos it’s slightly porous, just looks ‘wrong’!
            Pure quartz just superb!

          • @Newby: The trick is to knap the cortex (the white outside) off the flint and then knap it to the shape you want. Then start to polish. I had a friend who could produce a polished axe in about 2 days. I’ve got a flint arrowhead earring (courtesy of the chap off the telly) and several polished flint pendants made by other friends. They are unusual so get a lot of comments! 🙂

          • As Noto-etc. says flint is not gem quality – it doesn’t play light like quartz or crystal – it’s unusual rather than pretty. I’ve got a pendant made of slate which also gets noticed and, again, it’s unusual.

  11. Introducing the VAI – Volcano Attractiveness Index whereby a volcanic performance is rated according to three criteria:

    * Length of foreplay. It should be long enough to allow volcanophiles to skull up on salient facts, form an opinion and speculate on the when and how. Too short a run-up is as damning to the VAI as is a very long run up which causes impatience and interest to vane.

    * The eruption should ideally give a nice illustration of the eruptive processes involved and lead to a deeper understanding of volcanoes in general. Different modes of eruption as well as richness of phenomena observable are at a premium.

    * Aesthetic merits of the eruption. The eruption should inspire awe for the beauty and power of Mother Nature.

    The VAI for three well-known volcanoes:

    Etna (cbA) – Too unpredictable with very short run-ups to very short events typically lasting one to two hours that leads to most eruptions being missed by the average volcanophile. The eruptions are usually limited to Hawaiian-Strombolian activity with the occasional snow-induced “pyroclastic flow”. Aesthetically a most superior volcano.

    Eyjafjallajökull (AAA) – The run-up was long enough to meet the most stringently-applied criteria, not least of which was the fact that the month-long run-up allowed people to learn how to pronounce its name. For richness of observable phenomenae unparallelled; (sub)Plinian, Peléan, Strombolian and Hawaiian with volcanic lightning, volcanic bombs, drifting ash clouds and pyroclastic flows. Without question the most aesthetically pleasing and educational eruption of this century.

    El Hierro/Tanganasoga/Bob (cCc – A classic example of too long a run-up. Sub-aquatic eruption which resulted in some pumice and left an observable stain on the surface. Thoroughly unsatisfactory aesthetically. It is the considered opinion of this committee that unless this volcano addresses these shortcomings, its status as an active volcano be revoked.

    • 🙂 Nice and i agree. Elvis takes too long…I am not saying that as a volcanophile hoping for some action, but also because of the inhabbitant. They cannot stay away from their houses and work for month. They will return if they even fled. The more quakes happen, the more they will get used to them and not know, when it is really time to leave.

    • Absolutely.
      For the idea, the suggested criteria and their application on the chosen examples.
      We could think of a bonus for everything that is big/fat/huge/terrrrribly dangerous. Altough you somehow find it in your list. Nah, forget it – that’s too much randiness.
      Who shall we call to make this an official classification method? America or Russia? Ah no, now it’s China that rules the world. Or not? I’m puzzled. Thousands of years ago you would have clearly known it’s the Greeks. Today things got complicated somehow. I should stop thinking of international politics and such stuff. Geeeez…

    • Great index Henri. Could you put in a volcano peformance for it being unusual? (e.g. Ol doinyo lengai’s carbonate eruptions or Pakistan’s peculiar 2010 Tor Zawar eruption)

    • Ok. Love it. Some additions maybe, AAA volcano did not produce pyro-clastics, but huge Glacial Flood on north side and mud-pumice-ash flows on south side. Not forgetting steam clouds from meltwater running onto lava and forming “smoke rings” out of main plume. *we see perhaps Sheepy Dalek version of VAI scale in a few minutes?*

      • While you’re quite right about the Glacial flood and the “smoke rings” – good spot! – take a look again at the April 17th time-lapse! There’s quite clearly a pyroclastic flow but as it occurred over snow and ice, it was revitalised and shot up several kilometers – proof if any is needed that the flow was hot. 😉

        • I raise you this, Henri:

          Eyjafjallajökull – May 1st and 2nd, 2010. Not because of any volcanic phenomenon it shows in particular; simply because it is so beautiful – visually and sonically.

          Apologies if it’s been featured before – but even if it has, it deserves a re-showing.

      • I’ll have to reconvene the committee then, and you know how hard it is to get Perfidio to agree to anything. (It was only after we inserted the clause about revoking El Hierro’s status as a volcano that he would, finally, reluctantly and ungraciously, agree.)

    • @ Judith

      Just looks like a system malfunction at 10.07

      Monitoring on all the other Canary Islands is functioning normally.

      Thanks for all your info Judith – splendid!

    • If I remember well there is no cut-off triggered by the number of comments. The cut-off appears after a specifyed number of days after publishing, which once has been increased by Carl.
      However, mobile phone connections get much slower when a post has many comments.

  12. Ok People, should i try to assemble some kind of post for today and add Alans riddle he just sent to me?
    ((( we should have a new post anyway, we are getting close to 1k comments on this one))) But it would take me some time to write up something. Want me to do it?

  13. Please could someone explain why La Plama and tenerife are moving horizontally as posted on earthquake report. ?

    ,,Update 06/07 – 14:28 UTC
    – A new Pevolca reports confirms what we have written earlier today and yesterday. Additionally IGN has reported that also the islands of Tenerife and La Palma are moving horizontally. The El Hierro activity cannot be the only reason for this horizontal deformation. IGN also sampled air and water in the earthquake epicenter area and has found no abnormal values.,,

    http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/

    • Could this be magma moving under both the islands aswell .

      If so this must be a huge amount of magma to do this .

      • I don’t think the movements are directly related but a geologist can probably correct me.

        When they say Tenerife and La Palma are moving horizontally, do they mean relative to a part of El Hierro ?

        In which case it could be the car is moving, or that the road and the garage are moving, so the text is not clear yet, I’ll go chase that link when I get a minute.

      • I dont think this is related to anything magmatic INVOLCAN reported that it was caused by something other natural phenomena that caused problems in the GPS network

      • They are not moving a lot horizontally, if you look at the stations http://www.02.ign.es/ign/resources/volcanologia/jpg/hierro2SVVRTRF_neu.png
        LPAL being La Palma ftp://ftp.geodesia.ign.es/ERGNSS/fichas/LPAL.pdf and IZAN one of the stations on Tenerife (IGN net, deformación ftp://ftp.geodesia.ign.es/ERGNSS/fichas/IZAN.pdf).
        Especially, as – like someone explained further up – that it is an automatic net which has to be corrected and is often moving a bit up and down without this meaning a lot in itself (no expert). BTW the stations are also moving a bit up and down vertically (to yr. right).

        I think (no expert) that the important input of magma under El Hierro during such a short time span would be moving the whole region a little bit. 🙂

  14. Hello All just read this on ER
    “Additionally IGN has reported that also the islands of Tenerife and La Palma are moving horizontally. The El Hierro activity cannot be the only reason for this horizontal deformation. IGN also sampled air and water in the earthquake epicenter area and has found no abnormal values”

    Is this something new or something that has been going on for sometime..that Tenerife & La Palma are also moving horizontally?

    http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/

    • sorry Judith, you beat me to it…by the time I actually work out how to paste the link onto my comment…I could have made sunday lunch, eaten it and washed up afterwards!!

    • Debbie great minds think alike and I think for the first time I have posted the correct link!! Think you must have been reading the article and just posted after me . Each day brings something new to discuss.

      • Hi Judith I was actually trying to find the actual IGN report they were referring to..but could not so thought someone here might well know about this already…maybe it is not connected at all with what is happening on El Hierro at the moment..but living on Tenerife, I would just like to be sure that there is nothing going on that I should be worrying about…..

    • How does this relate to La Palma and Tenerife though as they have had no earthquakes all the activity has been on El Hierro?

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