The Azores volcanology. Part 1

The Azores archipelago (Wikimedia Commons)

The Azores archipelago (Wikimedia Commons)

The Azores Islands

The Azores is an autonomous region of Portugal, situated in the Atlantic Ocean 1500 km west of Lisbon. It’s an archipelago of nine islands, scattered over 600 km.

The Azores settlements began first on two eastern islands, Santa Maria and São Miguel (grupo oriental) in 1439 and then on Terceira in 1450, on Pico and Faial in 1466, on Garciosa and Sao Jorge (grupo central) in 1480, and on Flores and Corvo (grupo ocidental) at the start of the next century. Historical records of eruptions therefore extend back only between 500 and  600 years, but over 30 eruptions have taken place during this period, either on the islands or off shore.

All the islands are active except Santa Maria, which is the farthest from the Ridge. Fumaroles are their only persistent manifestation. They make their best displays in the Caldeira das Furnas in São Miguel. Weak fumes usually issue from the summit of Pico do Pico, and the earthquake in May 1958 briefly revived those in the caldera of Faial.

All except Sao Jorge has been stratovolcanoes and all except one have been decapitated by calderas. Pico do Pico soaring to 2351 m above sea level, is the only stratovolcano which still exists on Azores archipelago.

Mount Pico or Ponta de Pico. Photo by Marco Derksen (CC-NC).

Mount Pico or Ponta de Pico. Photo by Marco Derksen (CC-NC).

The Azores and their submarine plinth grew up on the Mid-Atlantic Ridge near the triple juction of the north American, Eurasian and African plates. Their activity is probably related to a hotspot “The volcanic activity in the Azores was  most probably also intensified by one large, or several small, hotspot plumes [Feraud et al. 1980]” and perhaps also to a secondary band of seafloor spreading. Whatever the reasons behind the growth of the Azores, all display a common and impressive predominance of stratovolcanoes, rifts, faults, fissures and volcanic alignments, running parallel to the spreading axis, that have been the leitmotifs in the development of their scenery. Magmatic emission in the archipelago are much less frequent; the last formed Capelinhos in Faial in 1957-8, although other eruptions have since occurred below sea level.

The Azores are young. The eastern group contains the oldest rock, which reach about 5 million years old in Santa Maria and 4 million years old in eastern São Miguel. No lavas on any of the remaining islands are apparently more than a millions years old. The oldest rock commonly outcrop in the southeast of each island, and the more recent eruptions have tended to occur in the northwest, nearest the Mid-Atlantic Ridge.

Nevertheless, there was no regular progression of eruptions from island to island towards this ridge. Thus, for instance, Faial, in the west, and São Miguel, in the east, both have some of the oldest and some of the youngest lavas in the archipelago.

The eruptions in the Azores produced a predominance of alkali basalts, hawaiites and mugearites, but some evolution to trachytes and pantellerites was associated with the violent explosions that formed the calderas. The basaltic rocks, commonly erupted from fissures, formed many cinder cones and lava flows, and Surtseyan eruptions took place where these fissures extended into shallow water.


This photo was taken by friends of Renato Rio and sent to Spica by him. This is a German article from Wikipedia explaining the rocks on the photos:éus_dos_Mosteiros


Volcanoes of Europe. ISBN 1-903544-03-3 (Alwyn Scarth, Jean-Claude Tanguy)
Self 1976
Ridley et al. 1974
Moore 1991
McKenzie 1972
Laughton & Whitmarsh 1974
Weijermars 1987
Krause & Watkins 1970
Searle 1980
Feraud et al. 1980
Abdel-Monem et al.1975
Booth & Croasdale 1978


Once again there is 3 volcanoes, one famous volcanologist and a volcanologic term to be found. In the lead it is very tight with Sissel grabbing a 1 point lead before Evan Chugg.interesting-stupid-facts-5

  1. Ultimate dragon with the heart of a + image – Katla the Dragon from Astrid Lindgrens book Brothers Lionheart (Dinojura44, 2pt) Sidenot, the Lion on the image has the same hairdo as the author had.
  2. From Gubbio to Eyfjallajökull while watching Dante’s Peak – Erik Sturkell, papers on Eyjafjallajökull and Gubbio, favourite movie is Dante’s Peak (Dorkviking, 2pt)
  3. In this abode I rest – Magma reservoir (chamber) – (Sissel, 2pt)
  4. Symmetrical (Italian) dessert next to infamous apple – Paranicota near Pomerape (Evan Chugg, 1pt)
  5. Take your sails down, you are at home – Home Reef in Tonga (Edward, 2pt)
Score board
6 Sissel
5 Evan Chugg
4 Pyter
4 Cryphia
3 Dorkviking
3 Matt
2 Edward
2 Inannamoon
2 Kelda
2 Lughduniense
2 UKViggen
1 KarenZ

358 thoughts on “The Azores volcanology. Part 1

  1. #4 – Mojave… but I don’t know what is overly symmetrical about it.

    Apple Inc is based in the Santa Clara valley. Last I heard from him, Marty was rolling capacitors there. He was a Comm ET that I used to know… he got out after one hitch and went back home to Santa Clara.

  2. 1: Ultimate dragon or Último Dragón is a nickname for the Japanese wrestler Yoshihiro Asai. First try: Mount Asahi, an active stratovolcano in Hokkaido, Japan.

  3. And here is a rumination for Diana (mostly) :mrgreen:

    I have just found the epitome of being sexually frustrated!
    As I poked my head out onto the balcony I was greated by a warbling cuckold.
    For some reason this male found that it was a good idea to sit in a tree in the middle of the night, in minus ten degrees celcius, in the middle of a rather ample snowfall and sing for the non-existing ladies.

    I give the cuckold ten points for hard-work and zero points for brains and season awareness.

    • And that will be the end of Amazons effort to drone deliver their goods.
      If FAA makes a ruling they never change their mind.

      • They’re going to have their minds changed for them on this one. The problem is they HAVEN’T made a ruling – at least not a lawful, enforceable one – even though congress required them to do so years ago.

        There’s a court case about it at the moment. Have a read of the brief:

        Click to access FAA-v-Pirker.pdf

        It is the most careful dissection (and absolutely damning indictment) of FAA asleep at the switch, make it up as we go along ‘regulation’ that I’ve ever seen; he hands them their arses, gift-wrapped.

      • I do find it funny that the brewery tried to get away with it… Now, if it had been a large brewery (like coors, Miller, or Annhauser-Busch) do you think the Faa had jumped as quickly?

        • Even quicker. FAA is really not into having unregulated anythings up in the air. We are talking about the institution that needed 5 years and 10 000 man hours to test a 5 dollar latch for a toilett door before approving it. After the proces the cost was 20 000 dollars for the little latch.

          • True enough… A bit bloated research cost, what could they possibly have tested that latch for to cost so much? Were they making sure it would hold in the hypothetical situation where the airplane potty would somehow implode and form a hole in the fuselage?

            • It is rumoured that every part in an airplane require 6000 forms to be filled out. That probably does quite a bit to the cost.

            • Tell me about it we are just now getting into Aero Diesel technology , Mainly because of a lack of
              avgas world wide and diesels run fine on Jet, It took years just to get hi tech panels and aircraft
              approved and millions per company. Yet if you even think about a superior field mod…
              Like a friend of mine that has a Maule Bush Plane, and came up with a better door system.
              he is at $300,000 for a new type hinge and aluminum frame and no hope of an Supplemental
              type Certificate…
              I won’t even go into Airtankers and Firefighting Helos….

        • If it had been a major brewery, there would have to have been a large outlay of cash towards the politicians who have oversight of the FAA.

          Graft and corruption are the new American way. That’s how General Electric can get away with paying almost no business taxes in the US.

            • Same difference. All of them push their propaganda. Even Liberal Fox News. The bad part about them is that they try to pass themselves off as an opposition opinion. Thats the most insidious kind.

              “Trust us. we’re just like you!” {bullshit}

            • First time ever I have seen the word “liberal” and “fox” in the same go… Would kind of make CNN communist and god only knows what our news would be then 🙂 North Korean Swedish News probably :mrgreen:

    • My late father-in-law was an avid Ice Fisherman. He and his buddy Earl, no kidding would live for the day they could set the shack up on Lake St. Clair near Rochester, Mich (and Detroit)
      and fish, drink, fish, drink drink, fish all day. Once they and several others broke loose of the main
      pack ice and were ah, stranded, When the Coast guard showed up they weren’t too happy about
      being rescued…

  4. So I tried to Google Gubbio and Eyjafjallajökull together and the top result was Erik Sturkell… So I’m just gonna guess #2 = Erik Sturkell
    (goes off to the corner and reads the four pdfs on holocene volcanism while waiting for clue appendaging)

    • DING!
      Erik Sturkell has written papers on Eyjafjallajökull and Gubbio. His favourite movie is Dante’s Peak.

        • Actually never met him. His is rather hard to get hold of, I have tried twice.
          Swedish news have also tried a few times. In the end they gave up and interviewed me instead on the radio.
          His predecessor, Reynir Bödvarson, was different, he loved being on TV talking about volcanoes and earthquakes.

            • It was not SVT (They do the TV), it was SR (Radio). It was a short one on Sinabung. Persistant rumour is that I will end up in a TV sofa next time something in Iceland go boom.

              On his homepage. Not stranger than that really. Erik is at another University than I am, so not easy to run across him when I go to a watering hole.

            • Yepp, it is more than 1 000 kilometers in between us. I am almost so far to the north that the sun doesn’t shine. Quite literaly since I am pretty close to the arctic circle.

  5. An interview with Dr. Matthew J. Penn, about the stuff I posted on the previous page.

    [audio src="" /]

    Note: The guy conducting the interview has a horrible and harsh voice. Sort of like a whiney trekie. Dr Penn sounds pretty even toned.

    Still waiting for the Black Swan Volcano…

    Note: This is not in any way attempting to connect solar activity and volcanoes, that would be farking ludicrous. By “Black Swan” volcano, I mean a coincidental eruption that is totally unexpected. One that is highly improbable. Couple that with a strong Solar minimum and you could get some pretty unfortunate weather swings.

    Black Swan events have the characteristic of being extremely improbable, catastrophic, and explained away after the fact. Example: The Japanese tsunami was much larger than expected, was catastrophic, and the science behind it discovered new mechanisms of how it could have come about.

  6. OT but darned amazing and an example of someone have the cool to do the right thing.

    i have lots of time as a Jump plane pilot but never had to leave a perfectly good aircraft.
    But know many Jumpers who I would trust to do such an thing..

    • My uncle was a jump master in WW-II. He was always creeped out by that. He had to prompt paratroopers to jump when they froze at the door. Many of them close friends, many who never came back. I think it really screwed up his head.

    • I have only done low-jumps and there one would not have the time for it. One is mostly occupied with the ground coming up. I would though one day love to go sky-diving from altitude so I have the time to enjoy the jump.

  7. Answer to #1 is Katla
    … according to Wikipedia, Katla is a fictional female dragon from the Swedish children’s book The Brothers Lionheart, written by Astrid Lindgren. The name Katla is an old Norse female name and means either “the kettle” or “the boiler”. It is also the name of an vulcano on Iceland.

    • honestly I will be sad if you are dinged because I tried to post similar answer last night but fell asleep before hitting the “post comment” button…
      Ah well…

      • Sorry dorkviking, it must be what we call “beginner’s luck” … it’s the first time I comment or try to answer the riddles. I’ve been here since the beginning of Volcanocafe … but I’m very shy!!

        • No worries! 😀
          It was a good guess and I don’t begrudge you for getting it right before I did… At least it was not a matter of you posting while I was typing up my answer like has happened to me couple of times

          • Worst example I have seen was when nobody made a comment for 3 hours, then 4 correct answers to the same riddle was posted within two minutes… :mrgreen:

  8. Horrible images of pyroclastic-flow victims at Sinabung are appearing on internet news sites – it seems that there has been a major collapse of the lava flow that has recently descended the flank of the volcano, causing somewhat larger pyroclastic flows into areas that had been evacuated but some people had apparently been allowed to go back home after the relatively low levels of activity in the past few days. News reports indicate that between 11 and 14 people have been killed …

  9. This webcam timelapse (obtained by shows pictures from 05.30.41 to 15.03.14 local time today. The viscous coulée is well visible, as in the picture above:

    [video src="" /]

    And the time-lapse for 15.11.14 to 21.44.37 local time today:

    [video src="" /]

  10. No 4 is unanswered. Remember that I love wordpuns and that one of the words sought after might be un-english.

  11. 4: And then we have the Dame Blance dessert, unenglish for White Lady, which points to Iztaccihuatl, a dormant volcano in Mexico. “The name “Iztaccíhuatl” is Nahuatl for “White woman”, reflecting the four individual snow-capped peaks which depict the head, chest, knees and feet of a sleeping female when seen from east or west.” – wikipedia –

  12. Good evening all! Following an idea for the solution of riddle no. 4 I had to giggle reading this statement: “The James Bay flows were dated by fragments of marmalade pots left by buccaneers in 1684 that were subsequently embedded in the lava flows described by Charles Darwin in 1835.” 😀 (GVP, Santiago Isl., Galapagos, Ecuador)

    Well, the most famous Italian dessert is tiramisu, and New York is called the Big Apple – infamous enough it seems, but I cannot find any connection to a volcano here… 😕

  13. Let me point out that it is not an Italian volcano, nor the name of a pizza. The volcano in question is named something pretty close to an Italian famous Dessert that is not Tiramisu, and it is located close to an infamous apple.

  14. I am astounded that nobody in here is good at the best Italian dessert ever…

    I personally can scarf down endless amounts of Pannacota.. First to find a volcano that sounds like Pannacota and is next to an infamous apple gets the point. :mrgreen:

  15. OMG, this must be the worst eruption I have seen since watching Tungurahua! FL450 should be over 10 km high, more like 15 km. There is no access to the IGEPN website at the moment.

    • IGEPN is accessible but slow to load.

      I make it between 13km to 14km. Don’t know whether that puts it into the stratosphere or not at that latitude. Guess Carl or GeoLurking can advise.

    • It is below, but not with much.
      It is also a sign of a significant eruption, I hope that the locals are surviving it.

  16. Updates from Erik:
    UPDATE: It appears that pyroclastic flows are crossing the road at Los Pajaros.

    UPDATE 7:15 PM EST: Some reports are now putting the ash plume height at 10 km / ~32,000 feet while the Washington VAAC advisory mentions ash as high as 14 km / 47,000 feet. According to the official IG-EPN report, pyroclastic flows apparently moved down the slopes of the volcano in all directions as well.

  17. The local contingency plan is being activated:

    “Security ECU 911 said tonight that the zones of influence of the Tungurahua volcano are in Orange (Chimborazo and Tungurahua provinces) and that activated the contingency plan for mobilization of the population up to resettlement in the canton Pelileo.

    At the time reported the evacuation of populations of Chacao, Chambiato, Cúsua Pillate, reported the Secretariat of management of risks of the Ecuador.

    The National Institute of meteorology and hydrology (Inamhi) pointed out that the ash is heading toward the city of Riobamba.”


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