Volcanic trips – a visit near Hamarinn, Skrokkalda and Hofsjökull

Recently (2-3 August 2013) I went for a travel with a friend, around the region of Hofsjökull and then to Skrokkalda and Haganga, and near Hamarinn and Veiðivötn, and then passing by Hekla. This is my small report about it 🙂 and hopefully the first of several to come.

DSCN7737_small

The Sprengisandur region. Situated northwest and north of Vatnajökull is a black desert containing all the ash and lava fields from the biggest eruptions of Iceland. The landscape is bleak, the weather is often extreme, sandstorms reign, but the geology is all interesting. A few rare lagoons make the landscape surreal at times. Credit: Irpsit

It was a nice volcanic trip but we catch the rather common but somewhat crazy sandstorm, with extreme wind gusts, blowing sand, ash and even rocks, and very cold (but thankfully no snow – we knew it was forecast so he return back ahead of it). The weather made our trip difficult, and even more for the pictures (the camera was ruined with the ash inside) and we though it was not worth of trying our way directly to the edge of Hamarinn or Haganga; it was extremely windy, foggy and ashy there. Hopefully next year I will repeat the attempt. Nevertheless I loved to have seen those mountains as they are rather prominent and well visible from afar.

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We took this picture despite the approaching sandstorm. Hamarinn is visible in the middle, to the left Haganga stands out. In the extreme left of the picture, Skrokkalda is the ridge in the forefront, while Tungnafellsjökull is behind. Many ridges are extending from these central volcanoes towards the southwest (right side) in what we know as the dead zone. Credit: Irpsit

My impression was that all of this dead zone region is a volcanic field with plentiful of Pleistocene ridges, tuyas and Holocene lines of volcanic hills. Eruptions seem to occur everywhere, sort of a monogenic field – or rather let’s call them monogenic fissures and ridges.
I can’t see Skrokkalda or Haganga being a central volcano. They seem the product of just one or a couple eruptions, under the ice cap during the Pleistocene, while Hamarinn is large enough to could be considered a central volcano. Hamarinn stands out like a huge table mountain, just at the edge of Vatnajökull, but seemingly hiding a caldera beneath the glacier.
Pic:  http://www.vedur.is/media/frettir/jardskjalftar_eldgos/medium/hamar_221008.jpg Hamarinn central volcano. Credit: Jóhann Friðrik Kristjánsson.
Tungnafellsjökull is also large enough to be considered a central volcano, and it has a deep caldera at its top, completely ice-filled. I have a feeling because it stands out of the large ice cap of Vatnajökull, and with the ice in the whole of Iceland retreating every year, this could be one of the first big volcanoes to awaken to activity in the near future.
Behind it I could have a glimpse of the mighty ice-filled dome of Bárðarbunga, but it was mostly hidden in the haze. From all of these large central volcanoes, the fissures and ridges seem to pop out here and there, across a vast region to their southwest. There are a lot of hills just similar to Skrokkalda but mostly unknown to us here at volcanocafe. Each was a product of a different sub-glacial eruption.
Skrokkalda is the only one with a SIL station on its top – we saw it from afar, but the track leading to the SIL had a “just for staff” sign and so we did not go there. (I did not want to cause a tremor myself and cause a stir in volcanocafe . Anyways its quite a clever position to have a SIL but personally I would place it further south and i will tell you why.
It seems older eruptions were the ones at Skrokkalda or Haganga (Pleistocene), while the newest eruptions occurred further south, around Veiðivötn (870, 1477 eruptions) or Trollagigar (the eruptions of 1862). I wonder if this is a trend or not. However, Pleistocene ridges also occur further south, like alongside the Langsjór lake.

iceland_rifts_2

Iceland rifts. I did this map to show the many volcanic-tectonic rift regions (shown in red). The general movement of the tectonic plates occurs along the yellow lines. That movement can occur at a different angle to the alignment of the volcanic fissures. At the dead zone, rifting is almost perfectly aligned with the general movement of the European and North American plates. The most recent rifting eruptions seem to occur towards the region of Langsjór, with Laki situated to its southeast, and Veiðivötn to its northwest, while older ridges occur to the extreme southeast and further northwest, towards Hofsjökull.

To which volcano each ridge belongs is a matter of guess, and as Carl posted (Laki), it is my opinion too, that these eruptions come from a source of magma independent from what it is thought to be a central volcano.

I also found some evidence of what seemed to be pumice around that region, but little; mostly tiny whitish volcanic gravel but the weather was nasty when I found it and I just returned quickly to the jeep. Mostly, black basalt is everywhere across that region and it seems it is gas-rich (lots of holes in those volcanic rocks).

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Hofsjökull volcano. It is a large ice-filled caldera. From afar it looks like a giant ice dome. It makes Hekla look like a baby volcano. Credit: irpsit

Hofsjökull surprised me because it poses such a large caldera, and it displays evidence of recent early Holocene eruptions to its southeast (and also southwest) side. Those are mostly lavas and some mountains look like rhyolite. I could not find any evidence for recent big ash eruptions. I would love to have gone closer to it, but the glacier is surrounded by large outgoing rivers and seems almost impossible to drive or hike over there, without expert help (furthermore off-road driving is strictly forbidden). It is quite an astonishing beautiful volcano and enters my “worth to keep an eye on” list of volcanoes.
IRPSIT

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104 thoughts on “Volcanic trips – a visit near Hamarinn, Skrokkalda and Hofsjökull

  1. Thank you for the report and posting about it. If I do not travel to Japan next year, Iceland will be the country to visit. Reading it, I must make sure that I am ready for all possible weather every time. Very dangerous, If I take things for granted. 100’s of Kilometres of flat land, great for sand storms. It looks so barren. Do not understand were the next rift will be, more the south western side of Iceland or the North eastern side? Hope it does not hit the Lake District

  2. Many thanks Irpsit – looks fantastic. I’ll enjoy sitting down and reading that properly with a map of Iceland to hand

    • Thanks for posting it, Pyter. As I thought, p-flows, not lava flows. I wonder how come this kind of news come more exact in a Brazilian site rather than an anglophone one. Perhaps someone from Timor Leste who manages Indonesian languages…
      BTW, are you from Brazil? 🙂

      • Sou de São Paulo Renato, através desse site que me encantei com os vulcões durante a erupção de eyjafjallajokull; agora escrevo sobre eles no radar global sendo colaboradora .” Não escrevo muito por aqui por usar demais o google tradutor” 🙂
        http://www.painelglobal.com.br/

        • Muito prazer! Então chegamos ambos até aqui através da Islândia. Meu falecido pai amava os vulcões e sempre me falava da Islândia e da Nova Zelândia, ambos países vulcânicos e com características então para mim semelhantes. Sempre pensei que houvesse um só país: A “Nova Islândia”.
          Sorry everyone, but there is very seldom the chance to meet Portuguese speaking readers around this volcano world, and I had to throw this joke about my confusion between the two country names, which sound similar in Portuguese (Iceland and New Zealand).
          Temos um ilustre visitante que vem para pegar um “friozinho” em Sampa: Ukviggen.
          Now, back to English! Nice meeting you “Pyter”. Introduce them to the true “cafezinho” and I’ll show them some “caipirinha” – coconut is my favourite. 🙂

  3. VAAC Darwin reports ash advisory to FL140.

    http://www.bom.gov.au/products/IDD41290.shtml

    Backing out the edifice height that gives an eruption column of about 3.39 km above the summit.

    Using Mastin et al, the estimated mass ejection rate is 8.93m³/s

    A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions
    Mastin et al (2009)

    Mastin et al is intended to yield an estimate of eruptive rate based on sparse data.

    The transplanted Pyter post from the last thread is my doing. Thanks to Jamison for also reporting the event here. We could have missed it had you not done so. (GL)

  4. According to GVP the name is Paluweh, Rokatenda (not Rokatenga, as I thought) is the island’s name: “Paluweh volcano, also known as Rokatenda, forms the 8-km-wide island of Paluweh north of the volcanic arc that cuts across Flores Island. Although the volcano rises about 3000 m above the sea floor, its summit reaches only 875 m above sea level. The broad irregular summit region contains overlapping craters up to 900 m wide and several lava domes. Several flank vents occur along a NW-trending fissure. The largest historical eruption of Paluweh occurred in 1928, when a strong explosive eruption was accompanied by landslide-induced tsunamis and lava dome emplacement. ”
    http://www.volcano.si.edu/volcano.cfm?vn=264150

  5. Irpsit, what a wonderful post! I must confess I am envious of your courage to venture across the wilderness. Beautiful!
    Iceland is indeed a volcanophile’s paradise.

  6. Busy Sunday for Iceland :
    Sunday
    11.08.2013 05:33:51 65.156 -16.426 9.7 km 1.2 46.25 4.1 km WSW of Herðubreið
    Sunday
    11.08.2013 05:11:11 65.165 -16.391 2.9 km 1.5 90.01 2.2 km WSW of Herðubreið
    Sunday
    11.08.2013 04:27:39 63.464 -22.418 1.1 km 2.3 67.83 40.0 km SSE of Reykjanestá
    Sunday
    11.08.2013 04:27:35 63.615 -23.387 13.7 km 2.6 90.02 8.6 km SW of Geirfugladrangur
    Sunday
    11.08.2013 04:27:34 63.567 -23.438 16.4 km 2.6 90.01 14.5 km SSW of Geirfugladrangur
    Sunday
    11.08.2013 04:26:51 63.865 -22.483 4.0 km 0.2 40.8 3.5 km NW of Grindavík
    Sunday
    11.08.2013 04:23:23 63.701 -22.865 4.2 km 1.7 51.77 6.4 km SE of Eldey
    Sunday
    11.08.2013 04:23:17 63.581 -23.294 5.6 km 1.9 90.01 10.8 km S of Geirfugladrangur
    Sunday
    11.08.2013 04:22:20 63.638 -23.384 10.7 km 1.9 90.02 6.6 km SW of Geirfugladrangur
    Sunday
    11.08.2013 04:19:25 63.862 -22.506 8.8 km 1.5 84.06 4.0 km NW of Grindavík
    Sunday
    11.08.2013 04:19:18 63.636 -23.391 13.0 km 2.6 90.02 7.0 km SW of Geirfugladrangur
    Sunday
    11.08.2013 04:18:19 63.667 -23.391 16.2 km 1.7 76.31 5.3 km WSW of Geirfugladrangur
    Sunday
    11.08.2013 04:17:37 63.813 -22.828 9.6 km 1.6 37.33 6.2 km WNW of Reykjanestá
    Sunday
    11.08.2013 04:17:31 63.752 -23.197 4.6 km 1.6 35.06 6.2 km N of Geirfuglasker
    Sunday
    11.08.2013 04:06:21 66.198 -16.685 2.0 km 1.6 90.01 15.5 km SW of Kópasker
    Sunday
    11.08.2013 04:06:21 66.226 -16.546 13.4 km 1.8 73.82 9.4 km SSW of Kópasker
    Sunday
    11.08.2013 02:56:15 67.058 -17.076 29.1 km 2.8 69.58 70.1 km E of Kolbeinsey
    Sunday
    11.08.2013 00:57:43 64.027 -21.193 0.9 km 0.0 76.13 3.0 km N of Hveragerði
    Sunday
    11.08.2013 00:10:19 64.133 -21.299 1.1 km 0.9 31.56 4.8 km N of Skeggi á Hengli

  7. Good Sunday Morning to you all. Lots to talk about and watch today. Firstly @ irpsit. Thank you so much for taking time to write about your expeditions. Not only do the photos bring Words like “Hamarinn” & “Skrokkalda” to life for me but the simple observations such as that about Hofsjokull caldera being so large fits another piece in my jigsaw puzzle picture of Iceland. I used to do plenty of long Hiking all round Britain and know how exhilarating it is to see and explore. Irpsit you do not know how much your posts make me stop and feel I am almost there with you. This makes my morning. I wish I could still walk like I did but these days a slow walk with Meg up our lane and over the wild, reclaimed sandpits is now my limit. Still good though 🙂 I see so much wild flowers and animals 🙂

    Rekjanes peninsular is rifting nicely. Quite deep quakes.
    Sunday
    11.08.2013 04:27:34 63.567 -23.438 16.4 km 2.6 90.01 14.5 km SSW of Geirfugladrangur

    http://www.disaster-report.com/2013/08/paluweh-volcano-eruption-2013-kills-5.html
    Mount Rokatenda is erupting. Thanks to Renato and Pytre for their alert.
    I am sure all our thoughts are with the Islanders and the grieving families. Latest news broadcast 1 hour ago. Language is not a barrier to understanding the full horror and tragedy to the Islanders. Blessings on them all.

    • I am not sure if the film above shows this eruption. It’s the wrong link! Certainly the reported deaths are. This is below is definitely the latest eruption footage.

      • Hi Diana, thanks for the videos! Even if the first one shows the Eruption of 6 Dec. 12,, it gives a vivid impression of what it might look like today.

        Your sekond video says Rokatenda in the description, but actually shows a Lokon eruption.

        • Thanks Granya. I don’t know about anyone else but I find it difficult to rapidly place eruptions and islands in this part of the world there are so many of them. I need to really focus on getting my geography right.

  8. Tentatively I would say there might be an underwater eruption in the making out at Geirfugladrangur. It is a volcano, and the earthquakes started at depth and quickly rose to the surface, and we have a bit of tremor.

    The last time this volcano erupted is believed to be in the eighties and have had massive quakeswarms during the last few years. The previous swarms was mainly tectonic, but this has a more magmatic signature.

    • If an eruption starts or have started it will though most likely not make us happy since it normally just produces a lava field on the ocean floor, and only a few fisherman will pass there.

  9. Thanks Irpsit! A first hand report is (to me) the beginning of the beginning of understanding what all the strainmeters and seismographs might be about. There are too many of them in Iceland to keep them apart, and mostly I have no idea what the mountains they are relating to look like.

    Actually youtube-ing for Mt. Rokatenda (or Paluweh volcano, on the Island of Pulau Palu or Palue 😉 ), I ended up watching wide-eyed this video of the Louisiana drillhole disaster in 1980 which lead to an entire lake being drained and sucked into a saltmine.

  10. Remember James Reynolds posted this video he shot at Paluweh a little while ago. This eruption looks like a dome collapse with associated phoenix clouds.

      • From the volcanodiscovery website on Aug 05, 2013 13:10 PM | by: T

        Paluweh volcano (Flores Sea, Indonesia): partial collapse of lava dome reported
        A partial collapse of the lava dome occurred yesterday and produced an explosion and (probably) pyroclastic flows. An ash plume rose to about 3 km (9,000 ft) altitude.
        Our friend Aris who visited the area after the event reported that bombs were ejected to up to 1 km distance and estimates that the collapse removed about 20% of the dome.

  11. Great bit of armchair travelling for us Irpsit!! Ever since doing the Tongariro crossing as a kid and getting lost in fog on a side trip to the the North crater in this eerie expanse of lifeless ash I’ve been hooked on volcanic landscapes. No fiction comes close to it.

  12. Eruption post request

    Anybody feeling up to writing a piece on the current deadly Indonesian eruption?
    If anyone has missed it I am talking about the eruption on Palue at Mt Rokatenda.

    And… Mark this up as an eruption I will miss very closely. I am currently in Singapore, I will see if I can swing by on tuesday, but probably not possible since my return flight is on the night between wednesday and thursday and I have a pressing errand here that I can’t skip.

    • From the Movie:

      “Are we gonna be heros, or are we gonna be colossal goats… in the end and this is the kind of stuff that gives you gray hear and makes this business really tough… you are driven and motivated to save lives, but at the same time, you don’t want to make people miserable for nothing. (David Harlow USGS.)

      From Wicker Peek at Ya.

      Cassandra was the daughter of King Priam and Queen Hecuba of Troy. Her beauty caused Apollo to grant her the gift of prophecy. In an alternative version, she spent a night at Apollo’s temple, at which time the temple snakes licked her ears clean so that she was able to hear the future (this is a recurring theme in Greek mythology, though sometimes it brings an ability to understand the language of animals rather than an ability to know the future).[2] When Cassandra refused Apollo’s attempted seduction, he placed a curse on her so that her predictions and those of all her descendants would not be believed.

    • Thanks a lot, Carl! I watched all 48 min of it and I now understand what the LP events are. Apart from that, it is an highly interesting (and sad) historical dokument for those N. d. Ruiz and Galeras eruptions.

      • Then you be safe in SE Asia, I reckon.
        Half way thu LP BBC film, seems Vesuvious is pressurizing!!!
        *scary thought*
        OT, speaking of Tanks.. Meeting a Russian T-55 tank in side street in Reykjavík this weekend, dressed up as “Tiger I” – a one converted for film work and owed by Swedish concern of all nations! Friends of you Carl ?

        – Well. Good to have one around.
        Tank can be useful in navigating in zones of heavy rockfall !

        • I’d like to see that “Tiger”. My late father in law was a Tanker in Patton’s 3rd Army.
          One day we were watching “Kelly’s Heroes ” Eastwood, and co. playing a tank crew
          on the trail of German gold. One of the features was a real,live Tiger tank. Carl, my FIL, was
          nodding off-we’d had some of his “Kentuck sippin’ whisky” and were watching the movie on
          the VCR. The sound was well,distinctive. “THAT’S A@$%# TIGER!!!) ” Carl was, for second about to dive under the rocker. “IF Ya’ll ever heard one once you’d never forget it!” He’d had
          a close encounter with one in the Battle of the Bulge..

          • Not spine tingling… but sitting on the stack for days on end, you get to know the sound of radars quite well. I had come home off of exercises and was asleep at home. I had this gawn awful nightmare that I was still on watch, at sea. As I came around… and woke up. I could still hear the distinctive sound of an SPS-40 air search radar. As I was brushing my teeth, I heard it again. I looked over at the bed and noticed that the speakers in the clock radio were making the sound. The 40 is a gawd awful powerful radar, and the clock radio was picking up the signal and modulating the speakers. The ship was actually several miles off the coast.

            Speaking of interferance. If you ever watch a video shot at sea, and you hear this annoying buzz in the video that comes and goes every few seconds… it’s likely one of the radars. I used to wrap the video cameral in layer upon layer of tin foil in order to cut back on it. I was tasked as the video guy to tape INCSEA events. (incidents at sea). Such as when a tattletale cuts you off out in open ocean. The tape is handy if the two ships tangle up and the event goes to court. Tattletales love to stop directly along your track and go DIW when you are doing alongside refueling operations.

            That one is all nice and glitzy… if you want a better look, from the vantage point of the refueling crew, here ya go 😀

            On some of the shots, you can see the black radomes of the ESM equipment. This is for the old WLR-1 system. Manually tuned, but with a sensitivity that could pick out signals deep down in the dirt of the noise floor.

            At about 8:32, you can see a P-3 overflight. IMO, the P-3 is a better platform to prosecute a sub. On one ship that I was on, a Brook class Frigate, I felt that the installed sonar was there specifically to piss off whoever was on the sub. We called it the “Helen Keller” sonar out of disdain for it. It was quite handy in foreign ports though. One way of thwarting swimmer attack is to randomly pulse the sonar. It had enough power to seriously rattle someones cage if they were swimming around in the harbor. If you caught them close enough, it could actually cause lethal injury.

            But.. to be honest, the sonar gear was some of the best of it’s type. Most of the issues have to do with the dynamics of the environment. A good sub skipper will exploit the different layers to minimize the chance of being detected.

  13. Carl? You’re in Singapore?

    Shit, I wish you better luck than I had. I was in “sundowners” liberty status due to an ET3 that was passed out in front of my locker in HongKong. Since I was late getting to quarters due to the ET being in the way of me getting into my locker and getting dressed, I was punished for my transgression by having to be back on the ship at sundown in the next liberty port. (Singapore). I still don’t think it was fair. However, it did lead to a really humorous exchange with the taxi driver when I told him that I needed to go to the port and back to the ship. He got it in his head that I wanted to go to a brothel. We were both communicating with gestures due to the language barrier, but I did manage to get across where I wanted to go. I made it back to the boat intact. I missed out on some of the sights there, but the torture museum I wasn’t really hankering to go visit. I saw some of the pics from the exhibits…. pretty damn gruesome. I imagine that the taxi driver and I were quite a sight, wildly gesticulating at each other trying to communicate.

    And that leads to the arcane and macabre.

    As some of you know, I love nothing more than to slam loon theorists who come in here preaching doom and gloom. Generally I slam them with data and kindly point to the part of the data that supports their claim. However, I do have to admit, I am also a loon. I have an interest in wild doom and gloom claims… mainly with the goal of ruminating on the possibilities and seeing if the data supports it. (natch). I am not an expert, but I do have a pretty decent foundation in physical sciences. Mainly from the point of view that if something can’t physically do what is claimed… it’s pretty likely unmitigated bullshit.

    Alternative view websites and magazines are fairly popular. On radio program that delves into this are is Coast to Coast AM. It was founded by a guy named Art Bell. It comes on in the wee hours, and you can usually hears some pretty wild stuff on there. The “Smiley Face” killers and “Dr Mary’s Monkey” are two of my favorites. I mentioned this to a friend of mine up in Birmingham Alabama, he also used to listen to it during the dead time while he was on patrol as a Deputy.

    Since Vesuvius has given us a little rattle and gotten our attention, a musical celebration by ZZ Top. In this song they use audio clips from the original Coast to Coast program. If you listen closely, you can pick them out as they play. “East of the Rockies”, “West of the Rockies”, and “Wild Card Line” are phrases used when answering the callers to the program.

    Note: My alternate choice was to try to beat the crap out of the ET… but I don’t think that would have worked to my advantage either. We were in the same division (to a point) and he never suffered any punitive action taken for that event. He was supposed to have been at the same formation as I. I think “Wheels” made it square though. “Wheels” was always the crafty one. (and a bit psychotic. I’ve known of him to go as far as to grab the arm of the guy bumping into him while he was working on the SPA-25 and then grabbing anode voltage to prove a point) Since I used to go drinking with “Wheels”, he knew full well of my circumstance and animosity.)

    • So far so good. I have also avoided the torture museum. I think I can do without the nightmares I would get from it.
      I am mainly on vacation, but also here to get rid of an expensive piece of junk that I own and do not want. And I need the cash for my next project.

  14. Three eathquakes in Hawaii, near Kilauea, the biggest one being an M 4.8 (USGS). Wonder what comes out of this?
    2013-08-11 15:54:05 UTC 4.8 31.6 km
    2013-08-11 16:06:48 UTC 3.4 31.3 km
    2013-08-11 18:24:16 UTC 2.9 3.7 km

      • Certainly not volcanic, he says.

        I looked again at the record; it stopped dead at 5pm yesterday, which immediately got me thinking of human activity. But 3am is a strange time for that to start again…

        • These signals look like mirror images. Perhaps something going up on serpentines, alternately coming closer to and further away from the seismometer, then going down the reverse pattern?
          Image and video hosting by TinyPic

          • imagine a large earth moving equipment, bulldozer, or a dumptruck. driving around on a bumpy gravel road. then turns around and drives the other way. Driving over the same bums, but going the other direction.

            • Driving over the same bums? It must be a hard life being a bum on Vesuvius when illegal garbage dump trucks run you over twice. 🙂

              Sorry, could not stop myself!

        • And nobody has ever seen it before…
          Nah, I think it is a new fumarole opening up. That would explain that one station picks it up well and the next one over is just able to pick it up. Still volcanic though.

    • Figured it was only a matter of time until we saw some more action. Definitely an interesting day for volcano watchers between Paluweh and Vesuvius.

  15. Here is the fun part about Vesuvio…

    Will the geologists and seismologists willingly hang their ass out for some enterprising sleazebag lawyer to later sue into oblivion?

    Italy does have a history of that ya know…

    • That is what really scares me.
      The risk is quite high that they will be a bit timid in their opinions and will have to be too political in their wording to do real good. Sad system.

  16. And there is no way to get to Palue. I tried to book tickets, but there is an air flight exclusion zone and the Island is off limits. I could go close enough and rent a boat, but then I would not make it on time back home. So Rokatendo is a nogo for me 😦

  17. Hi

    Things are still happening under El Hierro with a rise in the number of events per day.

    Here si El Hierro earthquake animation from July 1st to August 12th (morning).

    The little swarm which began a few days ago is still pretty much concentrated in the same zone. The strenght of the quake is quite low, but there seems to be more and more events lately.

    Data from IGN , NOAA

    I’ll do a zoom later today on the more active zone.

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