Mike Ross at Ambrym + Riddles

Mike Ross up late working at the rim of Marum cone at Ambrym.

Mike Ross up late working at the rim of Marum cone at Ambrym.

Our dear Mike Ross is currently at the volcano on Ambrym Island in Vanuatu photographing a documentary. Apparently Ambrym mean “Here are yams” in the local tongue.

Mike Ross 7

Mike wearing the latest fashion in volcanic face wear.

The volcano is a large shield volcano constructed by alternating layers of pyroclastic deposits and basalt. Around the year 50 AD the volcano had its last large explosive eruption that came short just below a VEI-7 with approximately 65 cubic kilometers of Dense Rock Equivalent being ejected.

The caldera that formed is 12 by 8 kilometers and within it is two large volcanic edifices called Marum and Benbow.

During the last century more cones formed at the highly active volcano. 1953 Mbuelesi formed, 1988 Niri (New) Taten formed and 1989 Niri Mbuelesi formed and Taten reactivated. All of these cones have erupted several times up until now. Ambrym has become famous for its persistant lava lake formations.

Michael Ross dwarfed by the gas cloud and rim of Marum Crater. Photograph by Bradley Ambrose.

Michael Ross dwarfed by the gas cloud and rim of Marum Crater. Photograph by Bradley Ambrose.

The current eruption at Marum has formed a lava lake and Mike Ross is there together with Geoff Mackley to recreate Mackleys famous video of the boiling lava lakes, but this time in extreme high definition movie quality.

I think I will just let the images speak for themselves and I know that I speak for everyone when I say that we are looking forward to the finished movie. A friendly tip, click on the images and watch the details, it is very much worth it.

Helicopter delivering the crew up on Marum.

Helicopter delivering the crew up on Marum. Mike with the movie camera. Photograph taken by Bradley Ambrose.

Living quarters in hellish light for the fireman. Not the ordinary mans campign ground.

Living quarters in hellish light for the fireman. Not the ordinary mans campign ground.

No words needed realy.

No words needed realy.

Mike hard at work with the RED Dragon 6K movie camera. Photograph by Geoff Mackley.

Bradley Ambrose hard at work with the RED Dragon 6K movie camera. Photograph by Geoff Mackley.

Down the hole.

Down the hole.


This week the riddly brainwrecks contain 1 volcanologist, 1 volcanologic term and 3 volcanoes. Last week we saw Evan Chugg take the lead followed by Pyter and Sissel. 2 points to be had before I add clues, after 1 point. For any newcomer I should give a hint, I love really bad word puns, so keep that in the back of the head when trying to solve the riddles.herring

  1. Windows for + image – Sill (Cryphia, 2pt), Windows has sills and the Swedish word for Herring is Sill
  2. Natural history of equestrian son – Gaius Plinius Secundus or Pliny the Elder (Lughduniense, 2pt)
  3. To BBQ, or not to BBQ, that is the question – La Grille (Sissel, 2pt)
  4. Icy mammalian edifice – Geirvörtur in Iceland (Edward, 2pt)
  5. The English most common volcano – Smith Volcano, or Mount Babuyan (UKViggen, 2pt) Smith being the most common English name.
Score board
5 Evan Chugg
4 Pyter
4 Sissel
3 Dorkviking
3 Matt
2 Cryphia
2 Inannamoon
2 Kelda
1 KarenZ


246 thoughts on “Mike Ross at Ambrym + Riddles

    • Odd spot for a Hekla earthquake. I have even a problem trying to decide if that quake belongs to Hekla or Vatnafjöll. Normally the quakes are clearly belonging to either of them, but that was both in between them and at an intriguing depth.
      Interesting one!

  1. And at the same time the Hágöngur that has not erupted in the last 10 000 years seems to be getting closer to doing just that.
    Uplift at the SKRO station seems to indicate a localized shallow emplacement and the ongoing “popcorns” have now gone on for weeks and today those have increased quite a bit in intensity.
    Notice, I am not saying that it will be erupting, just that there are signs of unrest.

    • I should probably explain that it is another Hágöngur sitting under the southwestern corner of Vatnajökull and that Hágöngur has most definitly erupted during the last 10 000 years. One of the eruption spread more debris into the glacier than any other volcanic eruption in Iceland. Quite impressive for an unknown volcano to have a VEI-6 eruption that nobody knows about…

      • suggest you name one HagongurV and the other HagongurU for unerupted and vatnajokull so we start to know which one you mean without you needing to clarify 🙂

      • And from that paper I noticed something as I re-read it… Strike!
        “A combined gravity and magnetic survey of Grımsvötn (Gudmundsson and Milsom,
        1997) revealed the existence of a 400 km3 intrusive complex in the upper crust underneath the volcano.”
        That is the reservoir of magma above the curie-point, so it is all eruptible. Now given the 10 percent “rule” we could assume that Grimsvötn has a capacity to erupt up towards 40 cubic kilometers of magma, and with a very rapid eruption and an opening down to the chamber it could very well produce a VEI-7. Didn’t believe the bugger was that big.
        It also points towards the previous 3 VEI-6 caldera-forming eruptions was only partial ones and a part of the development process of the volcanic storage. I had thought that they had destroyed the magma reservoir and that the reservoir had rebuilt in between each eruption.

        • That’s alot of magma ! Just one question, why would the Curie point suggest it’s all erruptable? That doesn’t say much about the gas contents. Only about the ferro magnetic metals in it and the temperature in my humble opinion. The curie point for iron is something like 1040 K and 1400K or so for Cobalt, the highest Curie point i know of. As i understand from quickly scanning the paper the lack of magnetic anomelies suggests the magma is above the curie point.

          • And that means that it is molten and not a sollid, and as such is eruptible. And we know that all Icelandic magma is gas rich so that is not an issue.
            Remember that for Icelandic melts, it is always hellishly gassy. That is why Laki had such profound effects.

            • But of course, that makes good sence, i just wondered if 1040K would be high enough to make sure it’s molten. And i know nothing about the cobalt content. If you just count the iron content you could get down to 800 Celsius, that’s a bit low for molten magma i think. Just some thoughts from a magnetic hobbiest.

            • The Grimsvötn magma is high in rare earth minerals so the curie-point is at a level that would indicate melt levels. Also the extreme gas content would help with inducing a molten state.
              I was though very surprised at the size of the reservoir.
              Nice discussion Arjanemm!

            • Thanks Carl, yeah the resevoir seems huge indeed. Nice discussion indeed 🙂
              Now it’s time to go to a real pub 🙂

            • If now you just had been a bit closer…
              Going to a real pub in while. Just going to have yet another one at home and dip myself in the bathtub first… 🙂

    • It is on the line Grimsvötn, Háabunga, Thordharhyrna, Geirvörtur, Hágöngur and Eldgigur. Hágöngur is though slightly slanted to the west so it is inside the base of the western glacier lobe. When I was there I was amazed at finding buss sized rocks in the ice that it had blasted out.

    • I recall that there was a big earthquake swarm that went southwest from Grimsvotn a few months ago. Does anyone else recall that?

      Or wait, Hágöngur is not on a fissure?
      I think that I have some of this wrong.

      • Hagöngur the cranky one is on the Vonarskard fissure. Hágöngur that erupted last in 1783 is on the Grimsvötn/Thordharhyrna fissure swarm.

  2. It looks an awfully, awfully long way down inside that crater to the lava lake: and that’s presumably with some foreshortening.

    Difficult to get a sense of scale but gives you the impression of great depth and, therefore size.

  3. It is Saturday… and I have popped a beer :mrgreen:

    A couple of weeks ago Lurking referenced to the Swedish group Rednex that he had seen. And I commented that they are so bad that they should never have been let out of the country. Thusly I indicated that they where an example of Swedish music that is really bad.
    Now I want to show an example of really bad swedish music for those who think Sweden is only having bands like ABBA, Roxette and Europe.

    Philemon Arthur and The Dung is one of the worlds last true mysteries. For 42 years hoards of culture journalists and other professional investigators have tried to find out who they are. Also thousands of amateur investigators have delved into the mystery without any success.
    In 1971 they released the self-titled album Philemon Arthur and The Dung. It was recorded on a bad recorder with crappy microphones. On the album they played on shitty instruments while you can hear farm animals in the background. The lyrics are juvenile and highly lacking of intelligence. They followed it up with the record “I want to vomit in your Umbrella”
    Somehow the first album was a limited commercial success and due to a gargantuan collective brainfart from the Swedish Crictics the group got awarded with the prestigious “Grammis” award in 1972. Everybody now expected to learn who the group was.
    As the award was anounced on the Award-show the infamous Swedish Porn-star Leena Skoog wobbled (drunk as a skunk) up on stage carrying a casette-deck and played their song “In kommer Gösta” (In comes Gösta) before barfing on-stage.
    The Grammis-award was cancelled for 15 years after that…

    So, without further adue, here is the worst song from the worst band in the history of mankind.
    You are duly warned: It will cause your brain to melt…

    • And in the defence of Swedish music… Here is my dear friend Göran playing Bach on lute. He is arguably the greatest ever classic guitarrist. Drinking beer with him while he plays assorted pieces by Beatles and Pink Floyd is a true joy…

    • And a shameless plug for the best Swedish band ever, The Bo Kaspers Orkester. Since they flat out refuse to sing in English you have most likely never heard of them. Here they have reached an almost mythical status and their endless tour is always sold out. It is the best kept secret of Sweden.
      They flawlessly jump between styles and genres, always with a cool swagger that nobody else has. Here is there Jazzy pop-song “We will always live”. I hope the music comes across without understanding the language. The lyric is brilliant though.

    • And a special for Lurking for just being Lurking…

      Here the Bo Kaspers Orkester are doing an electropop set that I think you will like. It is the ultimate swedish car-song. My translation. I know that the grammar is a bit hacked up, but it should be possible to sing it with the melody…

      “We sit in the same car, we sit in the same car
      A thousand years and a thousand miles, we’re sitting in the same car.
      If this is what you want, I can go a thousand [miles]
      A silver car, we sit in the same car.

      We sit in the same car, a silver missile
      A bomb in the opposite lane, we sit in the same car.
      If you fall asleep for a while, taken it out in a second
      For I have wanted to die with style, we sit in the same car.

      For we have each other, because we have each other
      There are those who say, I think it ‘s true.
      There is nothing, there is nothing we can not [do],
      For we have each other.

      I need you right now, for me there is only you
      For me there is only you, I need you right now.
      If you fall asleep for a while, taken it out in a second
      A silver missile, we sit in the same car.

      For we have each other, because we have each other
      There are those who say, I think it ‘s true
      There is nothing , there is nothing we can not [do].

      For we have each other, because we have each other ,
      There are those who say, I think it ‘s true
      There is nothing, there is nothing we can not [do],
      For we have each other.

      A thousand years and a thousand miles, we can go a thousand more
      A thousand years and a thousand miles, we can go a thousand more…

        • If you like Opeth… here is another of my friends from Naglfar… And yes, they do childrens parties.
          The big humour of it is that Kristoffer who sings is at the same time known as the most evil human on the planet and when they go out for tours hundreds of Christians turn out in protest and demonstrations, once their was even a Christian riot to stop them in Germany. His day job is as a Chrstian Priest and missionary… Plot twist 🙂

          • Repent! Repent! 😉 Funny how something that is relatively harmless brings out radical, and sometimes violent, religious fervour which is in itself hypocritical. But let’s not start that conversation, rules must be observed – unless of course it’s the wee hours of the morn and much whisky has been consumed and then all bets are off 🙂

          • That’s interesting didn’t know that about Naglfar.

            As much as I like Opeth and Kristiania (and Naglfar), I’m still kinda impartial to Black Ingvars… I blame my older brother

    • so maybe there are some seismographs reacting easier on the weather than others.

      Btw Didn’t you have had also rough weather? West-Flanders has been seriously hit by thunderstorms (low topped supercells). In Ieper (Ypres) there was a downburst with windspeed up to 150 km/h. There is some serious damage. Kortijk and Middelburg (Zeeland) seems also been hit.

      Right now, I’m getting the system over my head, no lightning, but some big windgusts.

      • The main activity went north of Lille. We heard some very very long rumbling (like 10 s, twice) , but saw no lightning bolts. some rain, but everything is quiet now.
        Hope you are well.

      • I think that low-topped supercells were probable that day, just like 3 January on which a low-topped supercell wreaked havoc in Schoonebeek near Emmen. A small tornado hit that village.

        Low-topped supercells occur in unstable airmasses with a Cape of a few hundreds J/kg and with a strong wind aloft which causes windshear. Windshear causes updraft rotation in thunderstorms, forming mesocyclones. Windshear occurs below a left-exit region of a jetstreak in the jetstream.

  4. Buuuut seeeeriouslyyyyy…

    Swedes in general never ever takes themselves seriously. I doubt that we will ever see an elite unite of soldiers from another country do this while they are in Afghanistan. These are The Royal Swedish Marines doing a dance number in Camp Sweden.

    • @Carl…. Star Wreck has hidden humor that sort of whacks English speakers up the side of the head. In some of the scenes that involve a Worm Hole, the translation to English comes out as “Maggot Hole.” I’m not sure how if it was intentional or not, but it was quite funny. Of note, some of the CGI people for Iron Sky cut their teeth doing the CGI in Star Wreck.

      • I think I get most of the humour, and wish I got all of it. Had missed the Maggot hole! :mrgreen:

        Now off for a beer at a local watering hole! (the one next to the giant ice hedgehog)

  5. 2 cents. Well… more correctly, my 2 cents. Take it for what you will, discard it if you wish.

    Some questioning has shown up as to the merits/logic of returning to a hazardous area to shoot new footage. I would like to address this from my point of view, but keep in mind that I am not the person treking off into a hazardous area, so my opinion may be worth shit. Personally, I’ve done a stint as a volunteer firefighter. At the time, there was no compensation for the activity. During an interview with the local press, our fire-chief, (at the time, Mike Slover), summarized the motivation of all the volunteers in the department. 1, we are helping the community. 2, the adrenalin rush. Combined, you get something that reduces insurance rates for the whole neighborhood. This is from increasing the survivability of anyone who finds themselves with a burning dwelling, and minimizing the amount of damage that comes from it. Personally, my reason was for the adrenalin, mainly. I also had an opportunity to dress up my military evaluations by doing something for the community. But, for the most part, it was the adrenalin.

    Mike Ross has found himself in a position to go to locations such as Ambrym. His skill set includes being quite adept at photography. Being fully aware of the hazards increases his survivability. At least we, the viewing public get to see creatures such as Ambrym in stunning detail. Shopping his imagery allows him to defray the cost of such an endeavor and allow him to undertake other such expeditions.

    Unlike the buffoons who yearly scale the Pacific northwest volcanoes and invariably get lost, Mike’s activities actually provide a social benefit. No only can scientists obtain his imagery, there are numerous potential geologists and vulcanologists who see the imagery and obtain the motivation to take that up as a field of study. I’d rather have them do that than providing mindless commentary on the activity of a Honey Badger.

    Carry on Mike, awesome imagery!

    • ditto. totally agree. When I first saw footage from Geoff Mackley I thought, aw this guys a bit full of himself, putting himself in the scene like that (it was storm footage and stuff like that and I guess I was suffering a bit from the old kiwi tall-poppy syndrome – I mean most kiwi blokes do crazy stuff, it’s in our genetic code).

      Later, when he put the footage of Ruapehu erupting (when he got hooked on volcaonoes) I realized the guys is simply turning his passion into his job. He’s found a way to market the stuff he does and to be honest I am totally grateful for the vicarious pleasure of seeing him standing at the edge of Ruapehu when it suddenly went haywire or a boiling lava lake in the middle of the South Pacific. These are images that are right up there with the best. Even on the video you get this chilling impression of just how powerful and huge this thing is. We need to see a human in the image to relate to it halfway. Can’t imagine what it must have been like to actually stand there. And for that I have nothing but praise for Mike and Geoff and all the people like him, showing us what this planet actually offers.

      And as for putting his life on the line. Hell, for that kind of experience I’d do it too!! It’s not like he’s posing any risk to anyone else like boy racers or any one of a million other idiots out there who actually do put other people’s lives at risk on a daily basis.

      • As I have mentioned several times, I was here for Ivan. A friend of mine was down at the Civic Center when one of the hurricanes was making it’s way here. They watched a certain Network TV guy dragging a fallen branch around trying to set up an exciting shot for his segment in TV. (Geraldo Rivera). Talk about a full on putz.

        • I saw Sam Donaldson’s dome doily get blown off by the prop wash of a Calfire S-2F (this was a
          piston version before they were converted to turbine) enjoyed that…
          Sam’s on my personal putz list…

  6. Grr…

    One of my “get something to eat” tactics when everything goes to shit is to grill up diced potatoes. Usually I try to do this with sausage. It makes a pretty quick and wholesome meal.

    My wife just requested that I make that for supper. Yee Haw.

    • … yeah, I know it’s a ruse to keep from having to cook, but I like it anyway.

      This isn’t a recipe, but generally here is how I do it.

      Fry the sausage up so that it is properly cooked. Drain the grease from it. Add vegetable oil (I use canola oil) While it is heating, dice your potatoes. Also dice one onion. Add to frying pan and fry until potatoes are soft. Add paprika as needed. If you are making a “heater” dish, substitute ground cayenne for the paprika.

      I drain the sausage grease since it’s an animal fat. Once the sausage is cooked, it doesn’t care.

      Works great for people who crave catsup, or who prefer to avoid that high sugar tomato concoction. For a more robust (and cardio hazardous) dish, leave the sausage grease in. Salt to taste but be careful to not overdo it.

      Personally, I add cayenne afterwards to my bowl.

      Caveat: I am not a cook. This dish falls more in the category of Bachelor Chow than anything else.

      For some variation, you can add an additional Onion and diced Bell Pepper.

      Remember, the goal is to get something usable into your stomach that doesn’t taste half bad.

  7. And… sitting here watching the spooky videos… you know, Yellowstone and such, one mentions that Toba erupted over a period of about 2 weeks. Wikipedia places the ejecta at 2800 km³ DRE. (1 x 109 m³ = 1 km³) Distributing that over two weeks I get a value of about 2,314,815 m³/s for an ejection rate.

    Poking around the Mastin et al formulas, that puts Toba’s 75 kyr bp eruption plume height at about 68.5 km. (between 68 and 68.5 km)

    On a lighter note, I finally figured out where the Exit Drive assembly is at in this thing I have sitting on my repair cart is at. Now I can replace it and send the core item back to the mfr. (woot!)

    • “Fractionation of olivine, plagioclase, clinopyroxene and Fe-Ti oxides explain most of the major and trace element variations in the resulting liquids and interaction between magmas rising from two distinct chambers combined with massive introduction of seawater into the edifice appear to be the major causes of the giant eruption leading to caldera formation. More recent activity of the volcano is principally related to shallow incremental batch melting or fractional melting and to fractionation in magma chambers associated with N100″ rifting.”

      • How about a little Offenbach?

        From Orpheus in the Underworld, The Infernal Gallop. The Dance has become a cultural icon, though it was originally intended (in this form) as an entertainment for tourists. (yeah, you probably knew that, but we do have occasional passers by… and it is Saturday after all.) My reward to myself for coming up with a plausible estimate for the Toba eruptive column height from 75kyr ago.

        Though I can no longer play trombone, I particularly like this version where the horn section distinctively stands out during it’s rendition.

        (I only made it to the State band camp level and gave up on it shortly afterwards when I changed schools.) Nothing beats a well balanced horn section.

        For a little history on the actual Cancan. It was the shocking dance of it’s time. 🙂

  8. Yesterday Carl and i had a nice chat about a huge 400km3 magmatic emplacement under grimsvotn. From magnetic evidence this body was found because it’s above the curie temperature or curie point. Above this temperature minerals/metals loose their ferromagnetic properties and become paramagnetic.
    Everyone knows iron is atracted by a magnet. If you heat iron above 1040 K, that doesn’t happen anymore.
    This property can be used to find bodies of magma that are above this temperature.
    I’ve been trying to find papers on this, but they are all behind paywall. But from all the bits i found i think we can only say that the temp is above 500 celsius.
    Cobalt has a Tc of 1400K but only in it’s elemental form, same goes for the 1040 K of elemental iron.
    Magnetite, iron oxide has a Tc around 500C, i think that would be the most abundent mineral in the magma that can have a magnetic signature that can be measured. Also from what i found cobalt compounds have a much lower Tc as the elemental form. I couldn,t find any exact numbers for the oxides for example. But i don’t expect the amount of cobalt in the lava to be high enough to be measured anyway.
    Then we have the rare earth metals like neodymium and such. They are used to make the strongest magnets around and icelandic lava is rich in such metals. The problem with these is that they have a Tc below room temperature and only specific alloys and compounds have a Tc max at 400C but usually only 100C or a bit more. I did find some highly fancy lab materials that can have a Tc up to 800C, but with rather poor ferromagnetic properties to start with and i doubt they exist in magma.
    In some cases Tc can go up by pressure, Buts that in order of 10^-5/atm or for some metrials the other way around.
    With all this said i don,t think the whole 400km3 is eruptable, since it just means it’s above 500C.
    Maybe if we know the shape of the emplacement, the surrounding temperature and the initial temperature, Geo Lurking can calculate how much of this body has a high enough temp to be eruptable. He made some nice plots about dyke intrusions before 🙂
    And ofcourse gas content should not be an issue in iceland..

  9. A couple of random thoughts:
    1. Ambrym: the paper Mike linked to above (previous page of comments) does talk of rhyodacite pyroclastic flows (up to 60m thick in some places) mantling the basaltic shield edifice of the island. These were apparently erupted in the initial violent phase of the caldera forming event. How they then came to get so broken up as we see in the videos I don’t understand, although there is talk of a plinian basaltic eruption following the initial rhyodacitic phase with highly vesiculated tephra, i.e. high gas (sounds like Tarawera!) and then, which I truly do not understand, Surtseyan activity (on the top of a mountain???) as “massive amounts” of sea water came to play a role in the eruption. Did the island get subsequently lifted as a resurgent dome or something. Whatever, Ambrym is a truly interesting volcano. It even has a rift trending EW whereas the suduction arc runs NS (guess where the caldera is.. you got it, at the intersection). Also two distinct magma bodies with primitive magma injecting into a fractionated body of more evolved magma at shallower levels. All sounds kind of familiar. Also signs of delamination going on in the subucted slab which also is close to a transitional point in the subduction zone (maybe some kind of slab window at play) Really intriguing stuff.

    2. Watching that wonderful timelapse of Etna with its series of strombolian bursts before each paroxysm made me involuntarily compare it to the continuous vulcanian blasts at Sakurajima. The long series of “puffs” before a sustained period of jetting set in. Let’s hope the parallels end at the series of puffs stage. I really wouldn’t want Sakurijima to go paroxysmal on us!

    • Perhaps there was a lake in the caldera before the Surtseyan activity, or the area was under the sea, depending on the time-frames 😕

      Rift volcanism seems to have occurred late-ish in the sequence so did the volcano cause the rift (magma upwelling) 😕

      • I was also thinking of a lake, like at Gaua, but they specifically mention seawater. I think you are right on the rifting. This is the axis on which the most mafic stuff seems to have erupted so if there was a large body of basalt rising along a crustal anomaly, like a tear in the crust, it looks like the likely cause.

        I must admit I didn’t really get my head around the paper in the first reading, I’ll read it again tonight to see if I can make any more sense of it. What I don’t really understand is the time line. Was the rhyodacite erupted in the same episode as the large basaltic eruption that followed it, which was ostensibly the cause of the caldera?

        Given that all calderas are a kind of collapse structure (with more or less explosive destruction of the chamber roof) I wonder why they infer this was not a typically massive caldera forming eruption. As Geolurking pointed the caldera has a surface area of 132 km^2 and the walls already range from 0 to 60 meters above the existing caldera floor and there has been a huge amount of subsquent infill. That would put a ball-park estimate of 500m for the original depth of the caldera, which is kind of indirectly supported by Mike’s 400m length of rope and the breccia encountered all the way down to the lava lake. this would imply a caldera of up to 66 km^3 – far more than the 29 km^3 originally posited.

        • PS I kind of suspect the ignimbrite was laid down in a previous episode and was blasted apart by the plinian basaltic eruption that followed in a caldera-forming eruption. (Tarawera showed us that plinian basalt eruptions can occur). I.e. the shallower fractionated chamber erupted the rhyodacite which formed the ignimbrite sheet. Later the mafic body powering the whole thing got to a shallow enough point and critical point where it erupted a high-gas and high volume body of basalt that then lead to collapse of the roof. This doesn’t quite explain why the breccia are so small, so maybe it was a pretty explosive affair.. I dunno… random musings on a Sunday.

          • Found this paper: “Robin C, Eissen J-P, Monzier M, 1993. Giant tuff cone and 12-km-wide associated caldera at Ambrym volcano (Vanuatu, New Hebrides arc). J Volc Geotherm Res, 55: 225-238.” In it, Robin et al, describe the various sequences of activity at Ambrym:

            1. Basal shield volcano with porphyritic, low viscosity basalt (pahoehoe).

            2. Ambrym Pyroclastic Series (APS) during which the most recent caldera formed:
            • Sequence 1: There may have been regional doming and fracturing following uprise of a magma body and / or seismic activity. The phase was Plinian, leading to collapse of the roof of the magma chamber. Some phreatomagmatic processes are considered to have occurred, which may have been caused by the interaction of magma with a lake and / or sea water. Lavas comprise dacitic PCF deposits: coarse ash, lapilli, pumice, cauliflower bombs and glassy casts; and, basaltic clasts.
            • Sequence 2: This was Surtseyan like. Lavas comprise vitric tuffs: thin and coarse ash with quenched glass fragments and accretionary lapilli; and, agglomerates of vitric clasts and shards, including basaltic lithics.
            • Sequence 3: This shows also some lava interaction with water in so far as there is evidence of rapid cooling. Lavas are basaltic grey to bluish ash flow deposits.
            • Sequence 4: This is more subaerial with Strombolian basaltic deposits and basaltic andesite lavas. The latter extrudes over the caldera rim.

            3. Post caldera volcanism:
            • Scoria cines, maars and fissures in the caldera
            • Basaltic lava flows from episodic lava lakes in Benbow and Marum craters; and, ash and scoria from the conduit.

            Not an expert so apologies in advance to Robin et al for any misrepresentation their findings.

  10. Also see Dr. BB’s latest two photos!
    Infernal mornings
    He says in his comments that the lava emmission “seems somewhat more significant” but bad weather is preventing observation.

  11. Goofing around with imagery…

    As a kid, Paladin was one of my favorite western characters (Have Gun – Will Travel) It just seemed appropriate.

  12. A bit of OT, picking up earlier musings, here is a well-balanced documentary about the typical German mindset. 🙂

  13. thanks chryphia for that, I am german by birth and lived there until about 19, it is amazing to see how much is ingrained in a person and still is after all this time, I have adjusted to the australian way of life, looking at the video I have to say sort off, was an eyeopener for sure, I will keep that and play it to the kids when they visit, as one of my daughters said a long time ago, just because a horse is born in a pig stay, it doesn’t make it a pig

  14. Good morning everyone!
    Fine discussion taking place at VC! I have missed some of it because I didn’t realize that I came back to readthe previous page (yes, I can be that stupid sometimes!).
    Taking the chance to wave hello to Bruce and friends who are victims of the extreme cold: well, in the last week we’ve had stunningly gorgeous days, 40 ° C and warm crystal clear sea waters, so I’m enjoying the rest of my summer vacations at the beach. Cannot complain, because while in Europe, I was very lucky with the weather and in 25 days I only saw one rainy day and above freezing temps.
    My colleagues at the University are heading to Michigan and invited me to go along, but I said “no way” I could join them: when Centigrade and Fahrenheit scales coincide that’s time to enjoy your side of the Hemisphere and the beach. I bet Ursh would agree with me, even though I’ll regret it when classes begin in February.
    A big envious hello to Mike Ross and his Vanuatu adventure!

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