Volcanic Organs and Gandalf’s Pipe

Gandalf, sorry Etna, huffing and puffing.

Back when I was a kid, I had two interests in life, physics and playing music. In music my favourite instrument was the church organ. Over the following years those two interests merged into one as I got interested in how soundwaves form, and onwards into what I usually call waveform theory. Waveform theory is applicable to many things from large scale physics all the way down to quantum electro-dynamic interactions, and volcanoes.

I also have a deep-rooted love of deducing on my own complex things from basic principles instead of root learning mathematical formulations. The reason for this is that I can’t memorize things if I do not understand them fully, and the only way of doing that for me is to walk my way from basic fundamental principles to the end result.

Combine that with a brain that refuses to see any problem from a single point of view and that rapidly tries to deduce five different solutions to a single problem from fundamental principles and you get someone with a propensity for over-heating the piece of lard that is the human brain.

Music and physics have always been integrated as a whole for me. In a sense of it I learned more about mathematics from the grand fugues by Bach, then I ever did by studying mathematics.

As things went on my love of Fugues, Riemann, inventing ways to cheat the lightspeed limitation and playing music was in the end slightly interrupted as I discovered that kissing girls was also quite nice.

I thought I should give a short personal backdrop for the third part of this article. But before returning to huge organs we need to contemplate Gandalf’s Pipe.

Gandalf’s Pipe and the Art of Smokerings

Gandalf fighting a Balrog complete with smoke ring. (Photo by U.S. Army Spc. William Hatton)

I must thank Janine Krippner for the idea of the first part. She trumped out a question to the Twitterverse about the physics of volcanic smokerings instead of using google.

So, for the edification of Janine Krippner I will explain Gandalf in a physics 101. This explanation will work for anything that has a somewhat round opening of the barrel and has a temperature and pressure differential happening.

I will first explain it from the point of a gun and then go for pipesmoking before ending up at a volcano.

Smokerings are governed by 3 effects, and Wikipedia gives a good explanation for one of them. The 3 effects are central piston driving force, friction of the colder outer air, and the Coanda effect.

The central piston driving force comes into play since the air in the center of the smokering vortex is travelling fast than the air on the outside of the smokering. This gives the inner side a positive energy surplus. Also, the same effect applies to warm central core air rising.

The outer air is colder than the air in the centre and colder air causes more friction than warmer air. This functions as an air brake.

These two effects will cause a vortex to form with the inner side spinning upwards and out (from heat and piston force) and a slower outside (from air breaking due to friction). The beauty of this is that the ring will be self-centring and will not disperse rapidly. As long as the principles are acting the vortex will happily spin about.

This pretty much explains what is happening if the heat differential is large, or the piston force is great, like from a gun barrel or a volcano. The problem with this is related to Gandalf and his poor mouth.

As any pipesmoker trying to blow a smokering can attest to is that it is harder to produce a smokering than you would assume. You have to blow out the smoke slowly (low piston force), and the smoke will come out at body temperature in a room that is normally room temperature.

Gandalf could probably conjure up dragon fire temperatures as he blows smoke, but for the rest of us we find that there is a decided lack in both piston driving force and temperature differential.

And this problem affects poor Etna as she blows her smokerings out of volcanic gasses. Problem here is that these circular vortexes of gasses does not emanate with great force, nor at a great temperature differential (for coming out of a volcano).

To explain this, we have to go back to early aeronautics and one of our most forgotten geniuses, Henri Coanda. As he designed an aircraft in 1910, he discovered that the exhaust gasses tended to stick to the surface of the fuselage.

In the aircraft example it was the tiny force of the ambient air pressure the forced the gasses towards the fuselage and there the friction takes hold of it and drags it across the skin of the fuselage. In a barrel, volcanic vent, or indeed a mouth, it is the pressure differential of the exhalation that pushes the gasses/smoke against the sides of the “barrel”, there the friction takes over and creates a vortex embyo even before the smoke has left the mouth.

Obviously, I have simplified things a lot here, but the basic parts are accurate. And since a barrel is a pipe of sorts, we are now ready to discover why Mayotte is a church organ.

Notre-Dame de Mayotte

Looking out over the ocean from Mayotte towards the possible future volcano. Photograph from Wikimedia Commons taken by Christophe Laborderie.

On the 11th of November this year an earthquake occurred near the Island of Mayotte. The combined seismic energy release was equivalent to an M6.1 earthquake. The duration of the seismic signal was longer than 20 minutes and it had an unusual monochromatic waveform.

What surprised me was that even trained geophysicists stated that this was a mystery. The surprise on my part comes from having seen this type of signal from volcanoes prior and during eruptions. Both the eruption of Tanganasoga in El Hierro and the 2014 eruption of Bardarbunga produced the same seismic signals at far lower signal strength.

With a 7-year head start on things I could smugly point out that I knew exactly what it was with a certain degree of certainty.

The easiest way to explain it, is to start with the humble organ pipe. So, please watch this video for the basic physics of how an organ pipe works.

Now, let me recapitulate that video to give some fundamental principles.

  1. The longer the pipe, the lower the note will be.
  2. The higher the air pressure is, the louder the note will be.
  3. The higher the air pressure is, the wider the pipe must be. Otherwise the note will start to transpond into higher frequencies.
  4. Fluid will also create a sound when going through an organ pipe.
  5. A volcanic conduit is to all points and purposes an organ pipe.

Geophysicists are very good at finding and explaining different types of earthquakes. But when an earthquake sized signal occur it is easy to get lost, especially when it is not even remotely caused by an earthquake.

We know from the prolonged and very energetic swarm of regular earthquakes that something is happening there. And from the trajectory changes at remote GPS-stations we know that it is something sizeable that is intruding in the waters outside of Mayotte.

Earthquake waveform of the Mayotte M6.1 Seismic Event. Signal recorded at Kilina Mbogo in Kenya.

Even before this large seismic organ note we knew that there was a volcanic embryo forming in the waters outside of Mayotte. It is believed that the volcanic region is driven both by the cracking of the African continent and the African super-plume.

Not an unreasonable assumption since it would take something fairly momentous to produce a volcanic organ note of such prodigious sound force. As such it is the loudest single frequency sound ever recorded.

Since we know the frequency and the volume, we could even in the end be able to get a fair assumption of the length and width of the volcanic conduit (organ pipe). Even though we will never be exactly sure of the result, we could at least remove the more outlandish candidates of length versus width.

We could then in turn make assumptions about the volume of magma that moved during the event.

Musical Coda

All of the large organ pieces by Bach work like immense mathematical formulations based on rules. They are the grandest example of the musical expression of mathematics and physical foundations of our Universe.

And as a coda to this article I would like to present to you my favourite organ piece, The Toccata, Adagio and Fugue in c-minor.

If you listen carefully at the beginning you will hear a question being asked, it is then explained in the next two bars through what is in essence a mathematical formulation. And as you keep on listening you will realise that the question is in effect the same as the answer and is super-symmetrical.

As the piece evolves the same question will come back and be proven through the variations of the theme. And in the grand finale you have five simultaneous lines of questions and answers solving the problem from five different points of view.

This is exactly how I see our glorious Universe, and it is hauntingly beautiful.



210 thoughts on “Volcanic Organs and Gandalf’s Pipe

  1. When I last swam
    I managed to do perfect bubble rings with my mouth .. as I layed myself on the pool floor ( to sink you exhale first )
    And using the remaining little air in my lungs
    Perfect ring bubbles large ones. I guess this is much harder to do than with air

    • I wonder if this would work with warm steamy breath during winter, if you exhaled very slowly or maybe super fast. I will give it a try. still fascinated by the boiling water in a mug turning to steam when tossed in the air, I feel compelled try try it when temps dive below 0.

  2. I’ve followed this website since it was established, followed Jon before that. It’s one of the sites I visit several times aday to see you guys discuss, very interesting indeed! Since I know very little about earthquakes and vokcanos, other than what I have learned here; so a “lurker I am”.
    Last week, on the Train to the airport (Oslo) there was a very short story on the monitor about an earthquake that had stunned geologists. According to the story (Three lines of information) this earthquake went all around the Earth and lasted for 20 mins (I think). I have tried to google this, but have not found any information on the web.
    Anyone here that have seen, or know anything about this?

    • Must ad that the “story” called it “a rumble” that went all the way around.

    • That’s exactly the story Carl is talking about at Mayotte.

      • Thanks 🙂 confirms what I stated above – do not understand much about the technicaleties, but I find Your discussions very interesting 🙂

        • Just scroll down to the bit beginning

          “On the 11th of November this year an earthquake occurred near the Island of Mayotte. The combined seismic energy release was equivalent to an M6.1 earthquake. The duration of the seismic signal was longer than 20 minutes and it had an unusual monochromatic waveform.”

          And all will be clear 🙂

    • They need to come to the UK and teach our lot a lesson. I’ve had pot-holes rip tyres off my car wheels. If they can do that in Alaska, why do we have to drive on roads that make the Grand Canyon look like a blip? Bah!

      • these are only temporary fixes….. hopefully will work until summer when more permanent paving will be attempted. … don’t feel bad, we have so many potholes every spring due to thawing we loose tires too! and those take forever to repair.

  3. Very interesting, particularly the detail about the resonance being picked up by seismic instruments around the world. Some animals, and some people, seem to have sensors for infrasound and ultrasound produced by tectonics in their immediate environment. I am intrigued by the possibility that certain types of events might produce a reaction at a remote location.

  4. Thank you Carl. Fascinating! As a very mildly autistic person I adore J.S. Bach’s music with its precision and mathematical niceties (although I have absolutely no head for figures). It is both predictable and still absolutely creative. Few other composers have ever reached his abilities. (OK, fan-rant now over!).

    And to see it applied to Mayotte is like honey on teacakes.

  5. Just brilliant, Carl, i even read this to my Hubby trying influxes to my voice as i imagined You would sound. Music is both basic and mysterious. i suspect that we are all instuments of the universe but some of us are off key. 😉 i’ve long been interested in the ultra sound of volcanoes as St. Augustine at the southern end of the Cook Inlet, gives me the “ebeegeebees” whenever it erupts but Redoubt, which is much closer, doesn’t. i cannot tell You how bad Augustine makes me feel= it’s like fingers down a endless blackboard which goes on and on without end….. realllllly bad… and yet nothing is in the normal range of hearing. ( Becoming aware of all the intersecting patterns of the world, as a child, i suspected a Pattern Maker. ) really enjoyed this one…. Thanks! Best! from confused motsfo staring out at my back yard with rain watering my green grass and rechecking the calendar… no snow…. it’s all gone! and almost 5 degrees C. amazing

    • I wonder if what you are ‘hearing’/feeling comes from VLF sound waves – these are known to have quite uncomfortable physical effects; and perhaps the shape of the conduit at Augustine and/or the way gases resonate in that conduit might have something to do with it? Think we need input from Carl here

    • Tremor from some volcanoes can indeed have some unpleasant effects on the human body. Such as headaches, nausea, vertigo and so on. It depends on the volcano, local ground effects and the frequency. So I am not at all surprised that you feel off by the volcano Mots.

      • I’m one of those too. discovered that when I was enjoying the presence of Mt. St. Helens. (Which is a lot like Augustine, as I recall.-a potentially nasty composite volcano) I would get headaches and sinus conditions, Annoying to say the least. and this was before May 18th, 1980..
        That summer I flew a single engine Piper Pacer to Ketchikan. two
        1.the ferry ride between the Airport and Ketchikan proper is no fun in
        bad weather.
        2. i was talking to an old Alaska sourdough-who just parked his DH Beaver
        next my little putt-putt. He said: “Yep Volcano weather happend all the time
        something blows up north …St Helens is just another Volcano messin’ with the weather.”

    • later in the day: ok, so now there is a light powdered sugar dusting the yard… has stopped but still only half way up the grass…..

    • Well Mots, good luck with trying to envision what I might sound like. Most people usually guess that I am from New England, but with a bit of odd linguistic quirks from Englishes all over the globe.
      Unless obviously I am in a goofy mood. Then I turn into an ever so slightly anemic version of Ya’mehcan. One of my odder talents is being able to fluently talk like a 18th century Carib/Jamaican pirate operating a sound system outfit at a bar.

  6. Thanks Carl Interesting comparisons and Yes, Bach is also my top favorit composer! Perfectly pure logics in musiv form!

    • Completely impossible to say since there are no good nearby instruments. All we can say that it is noisy, and that something rather big moved.

      To further expound, Bardarbunga was the previously noisiest volcano in regards of magmatic signals with at least five M5 seismic signals produced by movement of magma. So, hearing something 32 times more energetic is rather stumping.
      On the other hand, this is on the arse end of the African superplume, and we know that can move a lot of magma (and split continents).
      But even saying that there will be an eruption is beyond what we can do due to lack of finer details in the seismic signals, and stating the size…. well that would require a cup of tea leaves and psychic due to the lack of equipment.

      • If Holuhraun was preceded by magma-movement signals of a certain strength, and this new signal is 32 times stronger, would that suggest that the African superplume might be about to barf up a Skaftar Fires sized event somewhere near the signal’s epicenter?

  7. I’m still a fan of Toccata and Fugue in D Minor. That one will peel the hair off the back of your neck.

    • Here you go, same organist a few years later recording in Japan.

        • Well, they are really nice shoes. ← {I can’t believe I just said that…}

          No, I’m not some foot freak. Many years ago (pre-mil service) I used to sell shoes and appreciate well made footwear. And with as many boots I have worn into oblivion I tend to favor more common sense designs.

          And now that I am completely distracted, steel shank boots are a virtual necessity if you are going to be working aloft climbing around ladders for any length of time. Without that, your arches are done for.

  8. Coincidentally, Markus and I had the same teacher on organ.
    Here he is playing my favourite organ piece the Toccata and Fugue in F-major.
    The Organ is the organ from my home town Luleå in Northern Sweden. The Bishopry Church had a massive Grönlund Devil¨s Organ, quite a more Oompf in that compared to the two examples I put in before.
    As a kid I used to sit there late in the evening early night practicing.

    • so aware of the air componet….. wanting and waiting for the organ to ‘breathe’ 😉

    • Nice that someone else also made the connection to Bárdarbunga.

      As the eruption of El Hierro began there was very little information about the volcanism on the Island. For instance, it was not known where the central volcano and it’s plumbing system went. So, we had to do the legwork ourselves.
      Geolukring in here has the distinction of being the one both finding the feeder system of Tanganasoga and the dyke going out to Bob (Tagoro) through some very interesting data wrangling.

      At the time there was no name for the vent, so we held a vote and the vent was named Bob after a character in Blackadder (and obviously because of the bobbing restingolitas).

      In effect we named it a year prior to the name Tagoro being picked.
      Now you know why a large portion of the non-spanish speaking world calls your volcano Bob.

      • Yeah, we were quite amused at watching the media bobble-heads trying say Eyjafjallajökull, since no one had named it, we gave it “Bob” just to see if the bobble-heads would think it was a trick and wind up messing up that name as well. I was really hoping they would inadvertently use a long “o” and make it boob.

        As for wrangling out the feeder, what got my attention was that the initial quake set neatly outlined the main vent for Tanganasoga. You could clearly see the shape of the plug. Later the swarm filled in the intrusion area and made a nice cluster. Then it did the weird and the swam dove down under the keel of the island. That part extending down into the old sediment layers of the Jurassic era basin (now metamorphed into Phyllite). I was really thinking that it would come back up a scarp face fault on the other side. It almost did, but shot over to south of La Restinga. The white part of Bobs Floaters is mobilized Phyllite from that deep ancient basin. The dark chocolate looking stuff is the more juvenile fresh magma. Taken together (whole rock) they come out as Rhyolite, but individually (the dark intrusions) are more Trachyte. Local geophysical “scientists” got into an argument with a mainland university over how to classify the material.

        When we found out they were going to name it after a legendary carp or something, we stuck with the “Bob” nomenclature. Dunno how Tagoro fits into the whole scheme of things… but it is their vent.

  9. Excellent Carl and indeed its pretty view of the universe you have
    This reminds me of string theory somewhat

    • The basic idea of string theory is indeed beautiful with undulating circlets being the fundamenta of the Universe. But the theory built upon the basic idea produced gibberish in the end.

      This has nothing to do with string theory, but personally I think that we live in the beginning of another Golden Age of physics.
      A few years ago parts of experimental physics started to produce results not predicted by theoretical physics, or that is “off” from the expected result, take for instance the Higgs Boson, it turned out to have to low energy compared to the theory.
      Obviously there are a minimum of 4 possibilities why the Higgs Bosom lacked energy.
      1. We have an infinite series of even Higgsier Bosons out there to find to explain away the missing energy.
      2. Higgs was wrong somewhere.
      3. Our fundamental understanding of parts of physics is flawed somewhere.
      4. Or that the Universe itself is flawed somehow.

      Alternative 3 and 4 are obviously the more intriguing.
      If 3 is true we have work to do for a long time. And if 4 is true then we indeed have a problem to solve somewhere in the deep future.

      Anyways, that is why it will be no Nobel prize in the future for Higgs. Theory and proof must always match each other. He might though get to share a prize later on when someone has found the missing energy and explained it.

      • The latest theory on the Universe is -1. All to do with expansion and Higgs. Not being a cosmologist, physicist, (nor, in fact, intelligent I can’t offer anything other than that.

        • So unintelligent that I missed right the bracket off after ‘intelligent’. And that’s supposed to be minus one. Sigh. I think I’ll go back to watching the Borrowdale Volcanics for any upcoming eruptions…

        • How the feck did I miss this one. Sigh, my memory is really gone now.

          • Since I seem to have forgotten the aftermath of this. Did someone explain the energy lack, and he got a shared prize, or did they crap up and give it for a failed theory?

          • dunno about that,I wondered if it might be something like the recently mentioned ‘negative mass’ (which is said to explain darkmatter+darkenergy)?

          • Higgs explained why particles have mass (actually it wasn’t just him: other were involved in the theory). The missing mass is not his problem: that is just another particle that we haven’t found yet. Once it is found, it will have Higgs to thank for its mass.

          • He did predict the range of the energy, so it is a bit problematic that it was not found in the expected range.

            Well, good to know that we down the line will have a Higgsier Boson about to be discovered 🙂

  10. Just read the update from hawaiitracker today, and the most recent live update, and they talked about the two DI events at kilauea this week and how the tilt at pu’u o’o goes flat during the events, showing a connection. It hasn’t been addressed much but a month or two ago I remember there was a suggestion that the current DI events are caused by the deeper south caldera chamber and are actually much larger than the scale suggests, and this would also be reasonable if the east rift mostly starts at this point. Pretty much it shows that pu’u o’o and the summit are still connected freely and also this extends at least some way beyond pu’u o’o. This really means the current period of activity post pu’u o’o is going to probably be not too different to the period of 1975-1983, probably not large eruptions on the rift, but the summit could see some action, however after the summit fills up enough (might only take a few years or less) then more eruptions on the rift will probably happen and likely on the rift section just beyond the pu’u o’o complex down to heiheiahulu. There is also a certainty now that the system is pretty well intact and undamaged beyond the upper levels, so it will likely be business as normal in a not long time, though there could be some interesting summit activity in the immediate future.

    My guess (though I have a not great track record with these so far 😉 ), next eruption is in the caldera, if at the bottom of halemaumau there might be resumption of the lava lake and it could be long lived, if on the ring fault or upper ERZ, it probably won’t last more than a few days and be like other eruptions in these areas like 1982, 1979, 1974, 1973, 1971. If an eruption happens between mauna ulu and pu’u o’o, it might be a little larger, and like the 1977 or 1965 eruptions, with pretty low volume but being brief and intense and with maybe long lava flows that will be in the park, a flow on the north side of pu’u o’o could be a problem though after all that area was filled in in 2015.
    If an eruption happens downrift of pu’u o’o though I think it could be quite a lot larger, and evolve into a longer lived vent. Basically halemaumau or downrift of pu’u o’o it could be large and long lived, but anywhere else is probably a small eruption or number of eruptions.
    The magma conduit in the ERZ seems to be moving downrift, it started in the upper ERZ and until recently was in the middle, and now it is going beyond that to near heiheiahulu and I guess will eventually reach a point where everything will just break entirely with large scale collapse being the likely result. The fact that didn’t happen this year with an eruption that was so big it was previously considered impossible on kilauea probably means things still have a long way to go, are still not peaked yet and may repeat this years sequence possibly several times, and that the true terminator event might have the potential to dwarf even this years eruption, a sobering thought and definitely not the best case scenario that many are hoping for right now, Kilauea is well known in the present, but it’s past is one of the most unknown of all volcanoes, more is known about the ocean floor than about kilauea beyond 5000 years ago. A lot more study needed to to be done on the ERZ lava ages especially in the puna area but now that might be impossible.

    Well I did it again… ©longturtlehawaiicomment 🙂

    • Baugur was a much bigger vent than fissure 8
      Baugur was almost 500 meters long its so big that Oasis Of The Seas can fit comfortabley inside the spatter rampart and not be seen at all.
      As you say Holuhraun started off much bigger than Leilani 2018.
      During peak phase Holuhraun reminded me of Mordor or Io or Hadean Earth.
      The glow and clouds and barren landscape was an amazing sight.

      Both Baugur and Fissure 8 never formed shields as eruptive rates where too high.
      Both had an impressive channelized system the lava channels of Leilani and Baugur are the largest ones I have ever seen in my 23 years of life so far. Both Leilani and Baugur was connected to lava channels that where over 10 kilometers long and 100 s of meters wide too.
      The volcanocafe volcano map 3D globe haves some satelite shots of Holuhrauns drained channels.

    • @#Turtlebirdman
      I found another thickness map of Holuhraun flow field
      Its avarge is something like 20 meters with many areas going up to 30 meters.
      The 1,4 to 1,6km3 estimates coud be correct, the flow field is also around 20 km long.
      Holuhraun is all massive Aa lava, very massive Aa lava.
      The flow field is very thick and massive. 1,4 to 1,5 km3 is the current most acceptable models.
      Here is another flow field thickness map

      Beacuse its so very thick Aa in some parts.. it will form nice collumnar joints and cool solwy
      Kilauea IKI rootless lava lake will likley do some amazing collumnar joints when it have completely cooled as it is so very thick.

      • I guess the point still remains though, unless holuhraun exceeds 2 km3 the leilani eruption was still the bigger eruption even if holuhraun has a higher volume. Technically the biggest ‘fast’ lava eruption since 1783 was tolbachik 1975 which was about 1.7 km3 or more, and the biggest lava eruption full stop being pu’u o’o though with a few exceptions pu’u o’o was slow.

        It is worth noting though that 3 of the 8 effusive eruptions that have exceeded 1 km3 in the past 100 years have been from kilauea, which is another point in favour of its ridiculous supply rate. Pu’u o’o also exceeds the volume of all the others combined.

        Hekla 1947-1948 – 1 km3 total
        Mauna ulu 1969-1974 -1.5 km3
        Tolbachik 1975 – 1.7 km3
        Sierra negra 1979-1980 – >1 km3
        Pu’u o’o 1983-2018 – 8-9 km3
        Holuhraun 2014-2015 – 1.5 km3
        Leilani 2018 – 1 km3
        Sierra negra 2018? – <1 km3

        It is also pretty incredible that the most recent 4 of those eruptions were all in the past 5 years and were all simultaneous with 2 of the others…
        2010-2020 (especially 2018) is truly the decade of effusive eruptions, there hasn't been anything bigger than VEI 5, so it could be considered low activity by some, but more lava has erupted on land this decade than any other since the 1780s…

    • Awwwwww I miss the Holuraunish evenings at Mila Webcams and the yellow fountains dancing behind the spatter ramparts and the glowing sky and lit up pyrocumulus clouds.
      It was beyond magnificent.. beyond magnificent.
      I remebers strongly the lava channel that flowed away from baugur like a glowing road.
      I called that lava channel “saurons/ morgoths road” it glowed intensely with tornadoes and dust devils over it. Most intense was it in August, September an October 2014. The show made news in Sweden and Swedish Televison SVT vent to Holuhraun with volcanologists from uppsala university.
      Holuhraun made me many friends over FB and Gmail and a whole “volcano” family now I haves to talk with. Eldgosið i Holuhrauni

    • Holuhraun at peak strenght
      Its so strong that it reminds me of Puu Oo s early fountains and mauna Ulu fountains

    • Despite Holuhrauns high temperature 1188 C to 1200 C
      There was a supprsing complete lack of pahoehoe overflow
      features close to the vent channels ( overspills ).
      Leilani had that defentivly close to the lava channels and the vent Fissure 8 channel edges.
      Both Holuhraun and Leilani lava flows are almost completely Aa lava.
      Holuhraun likely had a diffrent compostion and viscosity than Leilani.
      Both eruptions where very fluid and Hawaiian but Holuhraun never produced any smooth overflows from its channels. ( only the lava channels in Holuhraun was smooth. )
      I think Holuhraun coud have been little more viscous than Leilani despite the same temperature.
      But in general both where very fluid and fast moving in the vents.

      Here is a overview of Holuhrauns compostion according to Haskoli islands
      “The basalt is vesicular and with about 2 volume % (vol.%) ofvisible plagioclase crystals, reaching up to 3 mm in diameter along with trace amount of clinopyroxene and olivine crystals. The groundmass is dominantly composed of brown silicate glass, but microlites of colorless and elongated plagioclase, short prismatic clinopyroxenes and olivinesare presentas well (see photomicrograph). These crystals are randomly oriented and make up about 20-25 vol.% of the rock. Sulfide blebs are present in trace amount (<1 vol%).Element concentration maps produced by scanning electron microscopy show that the sulfide blebs are Cu-Fe-sulfides"


      "The high vesicularity of the basalt indicates degassing at shallow depth in the conduit and at the surface. Loss ofvolatiles (mainly H2O)raises theliquidus (i.e. melting) temperature of the silicate melt, which promotes enhanced crystal nucleation without drop in temperature and results indegasing-induced crystallization of microlites. This abundance of microlitesexplains the relatively high viscosity of the basaltic a’a lavaformed by the 29 August 2014 event."

      The high eruptive rates during these 2 eruptions generaly forms only massive Aa lava flows.
      In Hawaiian eruptions high fountains and fast open moving lava rivers is what makes Aa lava flows.
      Fast eruptive rates makes Aa lava, and the two lava fields consists mostly of Aa lava.
      Fast eruptive rates makes Aa lava and smooth lava channels.
      In general the two eruptions where very similar with fast eruptive rates and massive lava channels and mostly Aa lava flows and fluid dome fountaining in the vents.
      Both Holuhraun and Leilani and Puu Oo formed generaly Aa flows as the lava cooled and never allowed to form tubes and shearing the crusts into rubble.

    • In general fast moving eruptive rates = Aa lava
      But as the data says.. Holhuraun coud have been somewhat more viscous than Leilani
      despite both where very hot

    • Something I did notice with my gif is how the eruptions seem to generally trend up the east rift starting in the pu’u o’o area and then going uprift more. I dont know why this is exactly as it also coincides with an increase in activity (not decrease like might be expected) but that could be seen as another support for activity resuming below pu’u o’o in the more long term.

      Places that I think are most likely for the next eruption,
      summit/halemaumau – 90%
      summit-elsewhere – 50%
      swrz – 10%
      upper east rift (hi’iaka-makaopuhi) – 40%
      mittle east rift (makaopuhi-pu’u o’o) – 70%
      lower east rift (pu’u o’o-heiheiahulu) – 70%
      lower puna – 20%
      anywhere else is very low.

      Also, something regarding the plumbing and connections within kilaueas east rift, during the deflation associated with this years eruption, the summit sank, as did the rift between mauna ulu and heiheiahulu (where I think there is a lot of shallow magma and where there is widely believed to be an open conduit), but the part between mauna ulu and the summit did not deflate abnormally, which means that this area has no shallow magma and probably also no true conduit, and this area doesn’t erupt either so that is another line of evidence. The east rift probably derives its magma from a somewhat deeper connection. This is supported by the recent trend of eruptions beginning on the rift without any summit eruption first, and by earthquakes often not appearing until well down the rift and distinct from the summit. The two are connected but it must be at a pretty deep level and with different structure than the simple assumption of a direct path at about sea level (which is too shallow anyway for how powerful some of the eruptions on the ERZ have been.

  11. Just a note:
    The 2010 event in El Hierro formed a new cone (which was informally called “Bob”) that already has an official name: “Tagoro”. However, it is correct that you refer to Tanganasoga, because it is the main volcano and the new cone is only another one, part of the same volcano (as the other 500+ El Hierro cones).

    And, since I’m writing, a little question:
    There is a lot of seismic activity in the “volcano of Enmedio” (“enmedio” means, “halfway”) between the two main islands (Tenerife and Gran Canaria) … Could it reach the surface (although it will not be seen by my eyes)?

    • To be exact, the seismic crisis started on the 17th of July 2011, and the eruption on 10th of October 2011. At the time there was no name for the vent, so we named it Bob. The official name was if I remember correctly assigned a year later after a mythical fish.
      It is the common form to state the parent volcano in general and the vent for the particular eruption. Problem comes with those few cones that tend to erupt often. That is why we say the Holuhraun eruption often instead of Bardarbunga, since this is the third known eruption at the Holuhraun volcanic fissure swarm.

      Enmedio is an interesting volcanic feature. It would obviously take a few eruptions for it to poke up through the surface. But it is definitely a possibility that it will occur in the distant future.
      As far as I know there has been no clear volcanic signals and that could be a sign that this is a tectonic event. But, as we know from Iceland, tectonic events on top of a mantle plume has a tendency to turn volcanic if they continue for an extended time.

      • Thank you, Carl… My fail: it erupted on my birthday but in 2011!

        • What a lovely gift, I wish something would erupt on my birthday. 🙂

          • Carl you will hate me for this then, but heklas last eruption started on my 1st birthday… 😉

  12. Very nice post!

    Cloud rings are not uncommon but the explanations are varied. The come from explosions, but that doesn’t narrow it down much. Etna blows rings. I have seen one covering quite a fraction of the sky that late was found to have come from a re-entry of a rocket. It caused an explosion high in the atmosphere. Meteors can cause cirrus cloud rings. Supersonic aircraft can do it without exploding if they cross a cloud layer. The one below was caused by a fireworks.


    • Explosive eruptions will generate really big cloud rings, tipically at the onset of the eruptions forming the head of the plume as it rapidly rises. The ring is not so well appreciable but it is the same process of a ring vortex behind it. It is present in many different situatuions, in growing cumulus clouds or downbursts hitting the ground. All that you need is a mass of fluid with a spherical or cylindrical shape moving through another fluid and tipically for this to happen a density diference is required, in downbursts it is a blast of cold air and rain dropping from above while in an old lamp I had and in Etna’s rings it is an overheated fluid rising through another one. Alternatively meteors, airplanes or rockets can obviously generate movement of the air without the need of this difference in density

  13. Jesper, have you compared the volcanocafe map with google earth? The google earth image is taken before the eruption. You can see that the crater row existed before and was reused from the previous eruption. There are some new features now that are not in google earth: a couple of new craters, the large older crater to the south is partially filled with new lava and there are visible cracks in the ground running all the way towards Vatnajökull.

    • In Google Earth Holuhraun cannot be seen only the older pahohoe flows thats covered in Fjöllum river sediments.

      In Volcanocafe globe a large part of the new lava field can be seen
      But the Baugur main vent is missing.

      • Ah, I see now the stitching is a bit strange. The bottom part of the crater row is new, but the top part is from before the eruption. Still, the eruption reused and remodeled the old crater row.

        • Nope its the same old crater row
          Just that the right one is higher resolution

        • Thats the same old crater row in both photos
          The right one is just more detailed a better satelite shot of it

          • I marked where I beleive the stitch between old and new is. There is a distinct difference in detail on the different sides of the red line.

            Top part of the crater row is pre eruption, but bottom part is new.

        • amazing the details are
          But its the same crater row just under diffrent ligthing conditions and camera.
          The satelite is many 100 s of km abobe earths surface.. I woud enjoy even more detailed space photos.
          Thomas A: is there any ground photos from there before the eruption?
          I guess its an arera very rarely if ever visted at all

    • In September there were some high definition satellite photos of some parts of kilaueas eruption that could be added to the volcanocafe map until google earth updates, it includes all the main fissures except 17 and 18, and also where kapoho was. They are on HVO website.

      On google earth you can go to dates after 2015 and see holuhraun in full, why it isn’t the default I don’t know because it is cloud free.

      There still isn’t a full picture of kilauea after this year, but the latest pic is from May 19 and actually shows an erupting fissure with lava rivers flowing from it (I think it is fissure 20). It is always interesting seeing eruptions on google earth, there is a good view of nyiragongos lava lake too, and kilauea, and I think also villarica.

      • The later images of Holuhraun do not have full resolution. You can’t zoom in. That’s probably why they are not default.

  14. Look at the bottom big one. It’s partially filled with new lava in the right picture. Directly above, there are three new craters not in google earth. The google earth image has a lot more detail if you zoom in a bit more.

    • I think I’ll just stop trying to use my phone for comments. I don’t want to break the flow of every single comment tree.

    • same here.. it does the same
      I just blame trump and my old school bullies why nothing is working for me
      I hopes this vc issue gets fixed soon enough.
      Volcanocafe commenting can be very glitchy for me too.

    • Current VAAC (Darwin) shows FL250. That works out to about 83.69 m³ DRE/s. (using Mastin et al and yields similar results to Sparks et al)

      For them that don’t know, DRE = Dense Rock Equivalent. Tephra (ash) can be as much as 3 to 4 times the volume of the Dense rock. Ash is essentially pulverized rock.

      Note; Both Mastin and Sparks equations are based off of the heat energy needed to generate the buoyancy of the plume. Though it may sound fancy and precise, it is not. Per Mastin et al, the value calculated can be off by a factor of four. However, I have used Mastin et al over a series of consecutive VAAC reports and come pretty close to calculating the resulting VEI after it’s all done and over with. Right now I don’t have a good source for all of Manam’s reports. Darwin has rearranged their site.

      My method for doing the VEI calculation is to use linear interpolation to fill in the missing data on a second by second basis and then doing a integration of the values. Yes, this leaves a lot of room for more errors, but it gives a decent ballpark estimate of the VEI. Quite suitable for our purposes. (general discussion) I’m guessing their site rearrangement was due to inadvertently affecting airline travelers, so I’ll echo their statement about volcanic ash reports.

      “Any enquiries regarding interruptions to scheduled flights as the result of a volcanic event must be directed to the relevant airline/s”

      The last report they have shown for Manam is DTG: 20181209/0315Z

        • Well, people get excited and tend to emphatically state what they see. Sometimes they get it wrong, sometimes they get it right.

          Fact: Volcano go boom. That was reported correctly. While we may not get overly excited by a vulcanian blast, a first hand viewer would be suitably impressed. I know I would be. I’ve never seen a volcano up close and personal… it’s part of my life mantra of “Don’t be there.” (It’s a survival mechanism. So far the most energetic thing I’ve seen is 16″ battery doing gunfire exercises off the Socal Oparea while in the firing line. We were a ship or so back of them.)

          • Exactly why I made sure to mention the near-certainty of VEI 3 in my VD report (and decided against mentioning “large” in the title)! Seemed to do the trick…

          • Almost certain to be VEI-2 or even VEI-1, a VEI-3 is more substantial.

  15. I remember the seismic crisis and its strange path under the island before the eruption, but the locations of the swarms occurred after it were even stranger…

    The name Tagoro comes from a berber word that means “a circular place to gather” that probably was given due to the approximat shape of the undersea cone. And extending to the fact the eruption gathered many social and scientific attention.


  16. v

    All the lava flows on kilauea that I have been able to find that date after about 1700. There are other flows in the 1600-1700s range further up the rift but poorly exposed, so I ignored most of them except pu’u honuaula, kapoho crater and heiheiahulu. The rest are maps released by USGS and pu’u o’o and 2018 are traced by me.

    /Right place? Not so much! See comment below.

    • (This is actually meant to be on its own, it is just a gif I wanted to post and it is better placed on its own so it is more visible and allows for separate discussion)

      /See the new rule. One thread per topic.

  17. A quick reminder, try to stay in the comment thread/tree.
    I cleaned away a couple of redundant or misplaced comments.
    We will leave anything that is containing good information/reasoning, but if it is misplaced and redundant we will ever so gently mop up a bit.

    • To expound a bit here.
      Kilauea is a nice volcano, but due to the shear amount of commenting that is done by a few commentators it kind of took over and hid all other discussions about volcanoes.
      As per usual we will never curtail discussions in here. But, we felt that something in the end needed to be done.
      Therefore we decided to try a solution, and that ended up being the Kilauea rule. You can discuss it to high heavens, but 1 thread per article. Feel absolutely free to make it a kilometre long tree if you wish.
      This way all the other discussions don’t get lost in the flood.

      We will not spank anyone for a mistake, that would break our own “be nice” rule. And trust me that even I am not exempt from the be nice part. My colleagues are quite adapt at yanking me in the ears if needs be. Rules are for everyone.

      • To encourage keeping related comments in the same tree, is it possible to:

        1. Increase the number of reply levels (with reduced indentation so they will still fit on the page). Now there is a maximum of 5 levels after which you have to go back and reply to a comment higher up the tree to get your comment below the current discussion. If no more levels are desirable, then a reply link that creates a new branch at the same level (i.e. equivalent to manually going up the tree to find the last functional reply link) would be helpful.

        2. Add collapse/expand to comment trees and branches.

        3. Find the bug that makes my comments end up in unwanted places 😉

        • 1. We can’t change the identations, so five is about as many as we can fit.
          2. I do not know if we can do that.
          3, Those of us who are not codiots like are looking at it, but there is a risk that it may be related to your phone.

      • There isn’t much going on at Kilauea right now either but what if there was to be a big eruption or particularly interesting event for some reason or another. I imagine that in a situation like that, like the Leilani eruption this year, there would be many commenters wanting to talk about very different topics. How should the rule be applied in a situation like that?

  18. Etna is still erupting from the new south east crater.
    Mild strombolian actvity and spattering and short Aa lava flows.
    The Puttisiddu vent is building a new scoria / spatter cone inside that crater.
    Magma is high and open now in Etnas magma system.

  19. High-altitude clouds can be Vulcanian (like this or Redoubt) or even Strombolian (Rabaul 2014). And I said VEI 3 because 6 hours at 45,000ft is quite strong and it did also have a 50,000ft event in August and activity has continued regularly since then so it is the same eruptive period; but the VEI scale isn’t typically assigned exactly when below 4 anyway as these are of course not considered as major eruptions. There is a video of this event by the way:

    • Hmm looks like I’ve been hit with the replying issue, this was supposed to be a reply to Carl…

    • Toba and La Garita must have been an completely crazy sight…
      Imagine all the volcanic lightning flashing everywhere!
      Toba and La Garita was an show in empty theatres… playing infor empty public….
      No photographers where there to see this awsome sight.
      We needs a timemachine.
      Imagine a really long exposure photo of Toba in action: lightning mania!
      Likley so much lightning in the skies thats its hard to see what it is when the photo is done.
      Puyehue, Calbuco flashes are sourely nothing compared La Garita or Toba flashes.
      The deadly Tambora was flashy too: but beaten in an instant by Toba and Garitas ash flashes.
      I wish there was a program that coud simulate the Volcanic Lightning in VEI 8 explosive eruptions.
      As fast as VEI 8 plinian and explosive eruptions can be the convection is very strong: they likley made Superbolts similar in strenght to jupiters bolts.

      I imagines ashcloud shields to bringed darkness to much of South east Asia and North America.
      And the pyroclastic flows.. a grey angry cauliflower wall from horizon to horizon.
      In La Garita a 100 km wide area sanked maybe 5 km as the 5000km3 dacite ash plinian was erupted and the caldera formed as the magma chamber emtyed.
      Of course +VEI 8 explosive grey eruptions impress me too.
      Toba, Yellowstone, Taupo, and La Garita: lightning mania!

      • I have read somewhere that Toba ash has been identified in sediment layers in Africa’s Lake Malawi – that is nearly 7300 km from Toba Caldera itself. Ash was being blown westward well over the Indian Ocean – remember that trade winds within 25 degrees of the Equator blow in this direction – from east to west, except maybe during El Nino events. I also remember something about ash from eruptions in what is now Yemen about 27-30 million years ago having also been detected in the seafloor of the Atlantic well off the west coast of Africa.

        If one applied the same logic for La Garita, it’s likely that ash from there could have gone well over the North Atlantic and perhaps as far as what is now the UK and Germany! Remember this was – and still is – outside the trade wind belts.

      • I thought there was evidence of most really huge calderas being formed out of effusive eruptions, eruptions that were basically flood basalts but made of silicic magma, but erupted at such high rates that they flow like basalt, with plinian activity being on the same scale as a more normal VEI 7. Tambora ash went a very long distance and an eruption 3-4 times bigger than that would still be relatively similar in overall scale but larger volume.

        This idea is entirely based on the post Albert made about toba though so i dont know if it is generally accepted, though it is a very interesting concept.

        • Toba must have been a totaly sick sight.. The ash column going up to space almost the overshooting top going up to 50 to 60 kilometers maybe
          Up there the air is just a few 1000 s of earths surface pressure.
          The air is extremely thin.. and the ash particles likley falls down to the stratopshere where they can float on the denser air there.
          Year after Toba event a thick layer of ash hovers just above the tropospause.
          The global cooling in short terms coud be 10 C but the volcanic Ice Age woud be short lived as the ash is washed out the atmosphere.

          • The Toba ejecta did not go up that high. It was mainly effusive, and the high latitude ejecta was mainly co-ignimbrite, carried by air heated by the lava flows. The lava flows were enormous, reaching both oceans. But the ash was limited for such a large eruption (a Holuhraun every 10 minutes!). Effect on climate was also minor, showing it wasn’t (largely) explosive.

          • I think at the time of the eruption the earth was in an ice age though, so it would have been far inland when it happened

          • Turtlebirdman is right – the Toba eruption was about ~75,000 years ago, placing it during the last ice age, which was from about 120 kya to 11 kya.

            While sea levels were indeed significantly lower than today, the western coast of Sumatra (and Java) didn’t extend much further west because of the Sunda/Java Trench and subduction zone. But to the east of Sumatra, the Straits of Malacca and the South Shina Sea were indeed land at the time of the ~75 kya Toba super-eruption.

          • ” Effect on climate was also minor, showing it wasn’t (largely) explosive.”

            Then why are the cretins on the catastrophe shows always hopping up and down about a population bottleneck at 75kyr? I can see not being able to find a bottleneck in Neanderthal from Campi since they didn’t make it around long enough to be examined in detail… but the 41kyr Campi event occurring right in the middle of their home range had to have an effect.

            I was watching a program about Campi earlier today and they noted how some of the Ignimbrite had flowed INTO a cave several km away and established a horizon over hominid artifacts and remains with no sign of occupation above the layer.

          • I don’t see evidence for a Toba population bottle neck. There was a division across India but later occupants showed the same culture as before the event, so the culture survived. There was some separation of population east and west of the eruption. As for a genetic bottle neck, that happened during the migration out of Africa. Almost all the genetic diversity in Sapiens is in Africa. Reportedly, a village in Africa carried more genes than all of Europe.

            The idea that Campi Flegrei impacted the Neanderthals is interesting. Of course, it was quite cold and the following period was the coldest of the ice age. They had more problems than just the volcano.

            but how did the lower water level in the Med affect the Campi Flegrei area? I wonder.

          • That’s a good question. I imagine most of the bay of Naples was dry land and the caldera itself was subaerial. Hominids hanging out next to the land near the coast would have had a rude awakening.

            As for the bottleneck thing, NPR is one of many who have written about it. Their source is Harvard biologist E.O. Wilson, but I don’t know if it’s just book hype.


            As for the Neanderthal thing with Campi, I ran across that idea from a documentary named “Neanderthal Apocalypse.” In other scribblings and videos, the range of Neanderthals is noted as going at least as far as the altai mountains, with the most genetic diversity of the group being towards that end of their territory. Dunno if the mountains served as a natural barrier between them and the Denisovians. Campi’s ash dispersal pattern blanketed pretty much the central and eastern areas of their home range. If it was evenly populated, that’s pretty close to about 66% of them being affected by the ash. If Campi was a stratosphere popper, then global temps would have worsened. (and with already being in an glacial maximum, probably not a good thing)

            Approximate shoreline at 120meter lower sea level. ≈21kyr

        • Yemen and Western South Arabia was home to large flood basalts as the large mantle plume punched into the lithosphere before the Red Sea formed
          I think that’s when the Afar Plume was young and powerful.
          Ethiopian highlands were also formed by large flood basalts that are associated with mantle plume activity. The same hotspot feeds Erta Ale and Jemen Red Sea islands. Soon the Afar Depression will flood and form a shallow salty very very hot sea that’s likely to reach the 35° C surface temperatures as the Arabian Gulf waters do in summers.

          GL Edit: “Soon” as in geologic time.

        • Then where are the massive sillic lava flows erupted by Toba then?
          I think this is an explosive VEI 8 eruption
          Thick viscous and gassy magmas tends to explode into an ashcloud

          • @Jesper → If any of my editing changes your comment from what you intended, please let me know.

            I tend to wander around fixing readability issues as I find them.


          • I usually only change things that pop out at me. Most of the time I try to leave it as is. I’m not a grammar twit.

  20. Hi Folks,
    Long-time lurker here with just the occasional post. As the lull between Hawaiian and Icelandic eruptions continues perhaps we can solve our Eruption Withdrawal Symptoms (EWS) and chat about a broader range of volcanoes. I’d love to hear more about the European mainland volcanoes outside of the big four, (Vesuvius, Campe Flegre, Santorini, Etna (Although I would welcome more about Etna’s internal plumbing. As far as I am aware I think the magma comes from deep, is this unusual for its location?) In an earlier article the Spanish mainland was mentioned as being interesting, Frances Massif Central, Alban Hills and even Germany’s Eiffel. I love this blog, its inclusiveness and reasoned science but it may have become blinkered (possibly deservedly to Hawaii & Iceland).

    Yours in Science

    • I know nothing about these, but I would love to.
      And this is my opportunity to congratulate the author of the post. I love it.

    • Technically the only European mainland volcanoes on that list are Vesuvius and Campi Flegri. Etna is on the island of Sicily and Santorini is an island itself. However the sentiment is one that I would support, along with an exploration of more of the volcanic past of the Aeolian Islands. After all it’s not just Stromboli that is an active volcano in those islands: the very prototypical volcano itself (Vulcano) forms part of the group and last erupted in the 19th century, and there are are also other islands that might have interesting eruptive histories as well.

      • Very good list, but even when leaving Iceland, the Canary Islands and Azores out Elbrus and Kasbek are still dwarfed by some European volcanoes. Of the currently active volcanoes Etna might be the biggest one. Elbrus covers a surface of 260 km² (according to the GVP, if I use a geologic map and Google Earth I get much less), Etna covers, only subaerially a surface of 1200 km² and also seems to be taller than Elbrus above its base, it has also 1/5 of the age Elbrus has. Another very big volcano of the continental Europe is the now extinct Cantal stratovolcano which covers a surface of 2500 km² though it was probably not as tall as Etna.

        • Fair point, and Etna erupts much more frequently. The volcanic zones are very different. Still, Elbruz and Kazbek are much taller (which is what counts in the tables). Kazbek also is far ahead in the recent casualty numbers – even though it is not normally included in those lists – and Elbruz is not as far behind Kazbek as one might wish.

        • Etna is one if those volcanoes that seem to have a continuous feed of magma from depth, similar to Kilauea and a number of the Icelandic volcanoes (probably also sierra negra, erta ale and the virunga volcanoes too). I don’t know what its yearly supply is, it is far less than kilauea, but that isn’t saying much really. The best guess I can get is that if etna really goes for it it can do about 0.1 km3 per year, as its 1614-1624 eruption has a volume of about 1 km3 and lasted 10 years. Etnas magma source is pretty weird too, it’s not really a subduction volcano but it also isn’t a hotspot, but whatever it is it must be very robust to do what it does. The magma isn’t as hot as the over 1500 C hotspot under Hawaii but it still erupts at an impressively high temperature, some of the lava flows in 1971 were very fluid, looking like the pahoehoe lava rivers in Hawaii and apparently erupted at about 1200 C. Given the characteristics, I wouldn’t be surprised if the 1669 eruption that destroyed part of Cantania was similarly hot lava.

          The 122 BC plinian eruption also erupted picrite with <50% SiO2, picrite magma seems to be a common element among basaltic plinian eruptions.

          Actually, I don't think there has been a post about etna on here at all, at least not since the old site, surprising. There hasn't been any posts on the afar region either, which is more understandable given that until recently it was very dangerous but that still doesn't remove speculation. Erta ale might be a modern day example of a monogenetic Icelandic-type lava shield, at the rate it is going now it is likely only a few thousand years old and has probably never really stopped erupting.

          • Iceland is pretty hot too, 1490 to 1510 C is predicted for the deep magma inside vatnajökull
            That makes the Iceland hotspot almost as hot as the Hawaiian one

            Etna is a decompression slab window astenopshere upwelling and slab rollback in a complex subduction – fault collision setting
            This is basicaly the astenosphere melting at avarge temps.
            Etnas. 1970 s and 1992 and some 2000 Etna flows where quite hot and fluid

          • But for most basalts Etnas lavas are quite viscous and stiff and makes strombolian activity. The lavas erupting now fron New South East Crater is one of the more viscous ones from Etna in the recent years

          • The volcanoes of Afar are very interesting, but are not well studied. Erta Ale seems to be the only volcano in the region that has a tendency towards producing lava lakes and long-lived eruptions, it is though very old, much older than any Icelandic shield, Kilauea shows that basaltic shields can have eruptions lasting centuries and maybe one that lasts milennia could be possible. If Erta Ale has had lava lakes for that long then maybe it could be considered one eruption but I really doubt that to be the case.

            The other 2 volcanoes of Afar that are seemingly very active are Alu-Dalafilla and Alayta. Their surfaces are comparatively young to other nearby volcanoes and would be great to know more about their eruption frequency but that doesn’t seem possible. But some of their recent eruptions indicate high effusion rates given the width of the channels and the high fountain deposits around many vents. Of course there was no one there to see the Alu-Dalafilla eruption of 2008.

            And there is Manda Hararo too which may have produced some of Afar’s biggest quaternary basaltic eruptions. The shields of Unda Hararo and Gablaytu might be better examples of Icelandic monogenetic shields. The events of 2005-2010 also show that Dabbahu and Manda Hararo are part of the same plumbing system, forming a 121 km long rift with a deep source and shallow reservoirs under Dabbahu. Fissures from this system can get very long, the most recent “big one” was 25 km long though the flow extension is of 81 km². Big eruptions seem to happen in the southern part of the system including the small shields but are really really unfrequent. More frequent eruptions are small and happen in the northern rift like 2007, 2009 and 2010.

          • Would you like to write a post on this? (Hint, nudge, promise of sweets and everlasting glory)

          • I think the only volcano I could write a post on is kilauea, for obvious reasns, but I think I have also said exactly what that post would be at least 10 times since August so it might not be necessary for a while… 🙂

            As for etna, I think there is someone else who I have reason to think is a lurker on this site who would be a much better person to ask about a post.

            For erta ale, I dont think it is more than a few thousand years old, at the rate it is going now it could have formed in 2000 years. And technically, I dont know if there is any way to actually prove some of the icelandic shields didnt last similarly long, with an open magma system but no active effusion for long periods.

          • Confusion… Alright I thought Albert’s comment was an inmediate response to the comment I had just posted. But I see turtlebirdman is up in the comment line and mentioning that there aren’t any posts on Etna and Afar. I am still not sure of who was Albert talking to, but I think to turtlebirdman?

          • I think Albert was talking to me but I dont really want to make a post

          • However, should kilauea start erupting again, I’ll be happy to write a very extended comment on it as usual :> Even if it’s just a small lava flow on the UERZ or caldera. If it happens in either of those places though I think it will be viewed by millions almost instantly with the several thousand people in the park at any time.

            Speaking of that, there was a general increase in the rate of uplift on the pu’u o’o tiltmeters, its still pretty small scale but the tilt is increasing twice as fast as a week ago while the summit has subsided a bit, maybe related to this, the jonika station is rising a lot slower recently, so maybe this partof the system is fully repressurised and the magma is filling further up the rift, and when it reaches the summit is when things get primed for eruption.

            One other thing I’m curious about now is whether HVNP will make pu’u o’o accessible by road, right now the road stops at mauna ulu because until now there has been no real reason to have it go further and so most of the ERZ is inaccessible until HWY 130, but the original road before 1969 went to makaopuhi, and a road to at least near pu’u o’o would probably boost tourism as everyone will probably want to see it in its final form after it had a hold on the island for so long and became such a big part of everything.
            In 50 years it will have probably stabilised completely and look like a bigger and steeper version of mauna ulu today, and with maybe even some forest growing on it on the tephra, it will look quite nice 🙂
            By then I think quite a lot more eruptions would have happened including some more shields and LERZ eruptions, but those are separate events. I doubt they are likely to last as long as pu’u o’o did though, maybe a few years to about 10, similar to mauna ulu and maybe with similar eruption progression.

          • The request for a post was in immediate response to the Afar information (but not listed as such as the comment tree has reached the end of its allowance). However, a post on Etna, Kilauea, or any other volcano from either of you (or others) would be most welcome! Best way to contact us is through the email above (volcanocafe.org@gmail.com). We won’t contact you on your registered email unless you specifically request that,

          • Actually I do have one other thing to add.
            A lot could be said about kilaueas December 1974 eruption, maybe not enough for a post of its own, but this eruption has some seriously impressive statistics when you look at it.

            Here is a picture:

            This eruption started in the night on the last day of 1974 only a few hours before the new year, ending a particularly active year on kilauea, with eruptions happening on all of the upper parts of the volcano. In total about 15 million m3 of lava was erupted, which doesn’t sound like much. However, the eruption lasted only 5 hours, meaning it had an eruption rate of about 1400 m3/s. The eruption is also noted to have been most intense over only a 1 hour period, so this average rate significantly underestimates the maximum which might have been twice this number.

            The other notable thing is the location, the only historical eruption within the seismic SWRZ, and almost in the koae fault zone. It lines up pretty well with the August 1971 and July 1974 fissures, and the later 1982 fissures, and those line up with a ring fault that intersects kilauea iki right where the main vent of 1959 was, and to me this is not a coincidence. The vents near keanakakoi erupted hot but evolved magma that was stored under the area, but the 1959 eruption was picritic, and December 1974 was almost so. This could be a connected system, and also connected to the east rift through complicated means.

            Most of the lava flow from this eruption actually happened after the eruption stopped, if the eruption lasted even 12 hours then it could have resulted in an ocean entry. An eruption like this but on the geologically almost identical UERZ or south caldera would be a potentially major hazard for the thousands in those areas at any time.

    • I’m still fascinated by Campi Flegre. It played a HUGE role in literally decimating the Neanderthal population by erupting right in the middle of their home range at ≈41,000 ybp. All that were left were relic populations on the periphery of their inhabited territory.

      • It left an impressive caldera, and perhaps not the best place to build a world-class city. But nothing is imminent apart from the common minor eruptions inside the current city limits. We actually don’t know what the run-up to a caldera-forming eruption looks like. What warning did the early mammals have before Siberia created its traps? It is plausible that there is 1500-2000 meters of inflation over a wide area before a Columbia-sized eruption. That must take 10s of thousands of years.

        • In all of my research on Hawaii, I found that it would theoretically take anywhere between 5000 and 10,000 years for kilauea to accumulate 1000 km3 of magma, though kilauea likely exceeds the average cenozoic eruptive rate of the Hawaii hotspot by at least an order of magnitude.
          In Hawaii this will never happen though because the volcanoes are too unstable and at best maybe a few km3 of magma can accumulate within kilauea before an eruption happens for certain somewhere, maybe 3 times more for mauna loa in proportion.

          Columbia river province is about 2/3 the volume of the big island, and lasted twice as long (2 million year peak) so the times between the big flows could have been something like 60,000 years apart. This is about 10 times faster than the hotspot does right now at yellowstone but pretty average in the grand scheme, and something completely possible today with the right circumstances (the very active virunga volcanoes with deep sourced alkali magma sit on an area of domed crust which is also rifting, the perfect storm for a flood basalt right now, just throwing it out there…). There are also fossils and sedimentary rocks between the flows too.

          I would imagine that small eruptions of normal scale would happen around the central hotspot in between flood lavas though.

          Something I am interested in knowing is what happens when flows of that magnitude reach the ocean. The fissure 8 flow is the only recent and well observed example of a flood lava flow (>100 m3/s) entering the ocean for any long duration (mauna loa 1950 ocean entry was only at that rate for 4 days and I can’t think of any other examples), it basically flowed into the shallow water of kapoho bay as though it was still on land. When the 100 times bigger roza flow went into the similarly shallow ocean at the Columbia river delta it must have just shoved the water out of the way and flowed down the shelf unimpeeded. I read that the flow also eroded the delta, or sank into it and re-erupted at several points with these weird rootless plugs being still exposed now.

          The really huge Deccan traps flows must have been similar but even larger, unlike the really long flow that went east, the majority of the flows (likely comparable in size) would have gone to the west and so their full raging volume would be discharged into the ocean. At that time the tethys ocean was still a large body of water as opposed to the small and almost landlocked basin it is now, and was a center of diversity for most large marine animals (most mosasaurs had a tethyan distribution from their fossils for example) and so having that much lava flowing into the ocean probably almost non stop would be a real problem.

          • I remember reading that the slope was a determinant factor on wether the flow got destroyed or flowed underwater.

            An ocean entry of this dimensions would have produced massive laze plumes and cause a rainy weather downwind. We saw this in a smaller scale with fissure 8 and I also was surprised to see that in the Pele-Hiiaka legend, in the parts regarding the presumed eruption the rain always came up.

  21. There were two earthquakes along the Veidivotn system this evening. But they haven’t been verified yet. Possibly deep quakes and around M1.5-M2. Interesting… But per se, it does not mean anything.

      • Looking at the drums there is a glitch with lost data at that exact moment. Probably caused a false detection by the automatic system.

    • Most likely cheeseburger quakes.

      (Meaning that the energy released is in the realm of the food energy contained in a cheeseburger)

      As opposed to my twinkie scale.

      • Most likely nothing. The first one is registered at 22:01:20. That is the same time as the signal is lost on all nearby drums. The next is registered at 22:02:32. That is the same time as the signal comes back. I don’t think this is a coincidence.

        Switching a signal on or off makes an artificial signal with a wide spectral content. The same signal appears on many stations at the same time and fools the automatic detection algorithm. The algorithm sees something, but also registers that something is not quite right (there should be different delays on stations at different distance) and gives it a very low quality. Those that are around 30% almost never make it all the way into the list of manually confirmed quakes.

      • “Most likely nothing”

        Which was the purpose of the twinkie scale. It came about a few years ago when commenters were getting overly excited about every little twitch that Iceland made. The purpose was to illustrate just how small some of those quakes were.

        • Well, even a twinkie quake is a lot more than a false detection, especially out in the dead zone, but I agree with your point.

          • My only reason for bringing it up was to premptivly curtail someone using our conversation as a basis for alarmist rhetoric somewhere else.

            Here, most of us recognize the quakes for what they are and understand the relative power involved. The point is that just because we are talking about them doesn’t mean they are overly significant.

    • As a general rule, twinkie and cheeseburger quakes are hard to localize… unless you see the pallet fall off the truck.

    • They don’t have to be Brit to be frothing rabid alarmists. The US press gives them a pretty good competition for endemic stupidity.

      • yup once science enters the journalistic world it seems to become a popularity contest as to who can come up with the worst scenario. Unscience in a way.

  22. Gorgeous picture of Mt. Semuru with the Tumpak Sewu waterfall infront, obviosuly taken with a drone, picture by u/ababsy over on reddit.

  23. Very Pretty thats Mordor after the war of the ring
    Fires of Orodruin/ Mount Doom have fallen silent forever
    The once dark black hostile landscape now blooms with sourthen Middle Earth flora and fauna

  24. I think Carl’s proverbial magma pillow just gave Iceland a little nudge from below. Seven quakes today between 18-30km depth. One between Hofsjökull and Bárdarbunga, one under Öraefajökull and an entire swarm at Askja.

      • Nice! It has been an impressive year for volcanoes, possibly the best since Krakatoa. Although not so good if your lives were touched by one of the eruptions.

        This is the image of the year for me. It was a screen shot from a web cam

        • I really like the juxtaposition of a moderneque view into a Hadean like landscape.

          I have always been a fan of surrealism 😀

          Parts of Hawaii have stood in as settings for other geologic periods. (Kualoa Ranch acted as a set for Jurassic park)

        • Yes! i remember ‘reading’ him during the flow… he kept insisting he had a clear escape route…. and he did…. impressive to track it live. Best!motsfo

          • He still took extreme risk. His escape route relied on nothing unexpected occurring, for instance a break-out crossing the road, or a methane explosion starting a fire at the opposite side of the house.

  25. I read that Nyiragongo was 1370C at upper vents in 2002
    making it the hottest holocene magma.
    Its likley that Hawaii may get that hot as magma supply gets faster.
    Hawaiis magmas at depth is over 1530 C
    Whats Nyiragongo source depth temperature?

    • If the magma is erupting at such a high temperature it is probably similar to Hawaii, actually it is probably hotter because it rises under a continent and is insulated, so even though Hawaii is a more powerful plume its heat dissipates more due to being under an ocean plate. This area is a flood basalt in the making, the crust is rifting and domed up at least 1 km above what it would be normally, it is pretty much inevitable what happens next…

    • Yup Hawaii is a very powerful plume and its almost hot enough to do ultramafic lavas.
      The Hawaiian hotspot is undergoing a boost. If it grows stronger it may churn out some komatites as Galapagos plume did 90 million years ago when it was a very powerful plume.
      The partial melting under Hawaii is very very high.
      Hawaiis deep basaltic magma in the plume partial melting zone is around 1530 C thats almost hot enough to melt raw iron. Still Ultramafic hot volcanism is mostly a thing of the far past as Earths mantle have cooled.

      • Only the upper mantle has cooled, the lower mantle and core have not, actually the core solidifying releases a lot of heat through its heat of formation, so the outer core might actually be even hotter now than it was then. Of course nearly all volcanoes are getting their magma from the upper mantle, but a few are getting around that…

        I agree that kilauea could erupt some ultramafic stuff one day, or at least the hawaii hotspot will at some point in the next million years or so, the mantle is so hot that the crust is probably entirely melted under the centre of the big island, like a massive magma sponge feeding into the upper system. I watched a livestream by John Stallman on facebook before, and he showed an idea about the magma chamber actually being much bigger than the actual molten pocket, maybe with as much as 30 km3 of magma in the highest estimate but it is largely solid with liquid dispersed within it. I somehow think this is unlikely though with the temperatures involved, there is probably a completely open conduit of liquid running into the upper magma system from the deep mantle source, and into the east rift at least as far as pu’u o’o.

        • Earths inner core surface is around 6000 C
          Its as hot as a G class star inside our planet.
          Outer core is 5700 to 4900 C
          The inner and outer core will make you blind if you coud see them, they are that bright shines intensely.
          White hot …

        • Below our mild temperate worlds wet green surface
          Is an inferno, and the nulcear furnace drive everything we see on the surface
          Mountains, Volcanoes, Earthuquakes, Landscapes, the mineral cycle, rock cycle and geologic carbon cycle.. all is driven by the #heat within
          without life woud have never even got started

        • The middle of Jupiter is 50000 C at least, like an O star in full wolf-rayet mode before it goes hypernova…

          Small stars and massive gas giants are way more extreme objects than a lot of media depicts them, proxima centauri has a surface gravity that would squish any solid to a flat sheet and is 10 times denser than lead. Proxima is nearly 200 jupiters in an object that is only slightly bigger than jupiter.

  26. wow the sun is quiet these days… is in the minimum of solar actvity.
    Not a single sunspot is visible. Only solar granulation.
    Not a single sunspot. The magnetism in the sun is resting these days
    The magnetic field lines have not become twisted yet

    • The official number as listed over at Spaceweather.com is 12 though I can’t see anything on the image they have of the solar disk.

      What is interesting, is that the strange data accumulated by Livingston-Penn seem to show that magnetic field strength of the sunspots is starting to return to more expected conditions. Below about 1500 Gauss, the the magnetic flux is not strong enough to clear out plasma from the flux tubes that make up a sunspot. They use Zeeman splitting to derive the field intensity of light from the middle of the sunspots. (the magnetic field causes the emission lines to separate into distinct bands. In this case, I think they are looking at Neutral Iron.)

      Dr Leif Svalgaard maintains and updated version of the phenomena as detailed in their paper. Nagovitsyn et al offer an explanation of a possible cause.

      A word of caution to anyone digging around to do their one plotting and looking at long term sunspot numbers. Make sure you get the correct data set. It has been known for some time that the “official” sunspot spot count suffers from observer bias. Within the last few years, the heavy hitters in this field held a series of working groups to come up with a way of correcting the record so that the bias is removed. They produced a “group count” data-set that satisfies many of those concerned about what constitutes an accurate count. From what I understand, even Ilya Usoskin, who wrote one of the more definitive papers on solar grand minima and maxima was part of the working group.

      And no, nothing I have read that carries any authenticity points towards us entering a Maunder like minima. Sure, some of my data plots hint at that, but I never got far enough with a curve fitting program to lend it any credence. And if I can’t convince myself of it… well, then it’s a pretty shoddy argument. And along those lines… it seems like the cycle length has more to do with the Global effects than the actual sunspot count itself. And in that, I haven’t really seen anything strange. (And you know I looked, I’m a Bond event fan and am always looking around for anything that could back my thinking on the matter. “Chiefio” claims ownership of the “Bond Event Zero” idea, but I’ve seen it in the plots and it should be right about now. No, the LIA was NOT Bond event zero. At best it was a half bond phenomena.) Is Chiefio right? Beats me. Actual Bond events were discovered from ice rafted lithic fragments and they seem to correlate pretty well to upheavals in society. They may be a Holocene interglacial representation of Dansgaard-Oeschger and Heinrich Events which are manifest in glacial max periods. How it all fits, or if it even does, I do not have a clue. This is the primary reason I came up with the “Don’t be surprised by anything no matter how unlikely it is.” idea. If there is a non-zero probability of it, it has to happen sometime, somewhere, to someone… eventually. (assuming infinite Bernoulli trials)

      And you can thank Carl for cluing me in on the idea of infinite probability. {And yes, this is me beating the Black Swan drum again} That’s the joy of volcanoes. You know it’s gonna happen, you just have to figure out where and when, and “Don’t be there.”

  27. https://www.youtube.com/watch?v=N-WqKmisAFU

    Wolf volcano during its intense opening phase.

    Being quite honest I dont find many volcano statistics very impressive anymore after my extensive research of kilauea, but this is something else entirely, the speed of that lava is utterly terrifying when you realise those fountains are at least 400 meters high…

    • Apparently between 450 and 540 meters tall based on the fall height duration as well as compared to the height of the volcano itself (1700 meters).

    • By my rough correlation that a 500 meter hawaiian-type fountain is about 1000 m3/s eruption rate, this part of the eruption was getting some rather large numbers, 7000-11000 m3/s, which is almost on the limit of being effusive. That lava flow in the middle, is moving at something like 30 meters a second, over 100 km/hr…

      • The problem with fountains is that they aren’t driven by heat flux snd the caculations from Mastin et al do not apply. Fountains have a more direct physically launched mechanism due to pressure and viscosity. Actual flow rates will depend heavily on orafice size, pressure and viscosity.

  28. I see that you are discussing how to better handle threads. Might I suggest Investor Village or Stockhouse format. The threads are much easier to follow.

  29. Just saw this after looking at the gps plot of the past 5 years, yes I know it is a new comment but this article is a week old and I assume a new one will be written in the next day. Also it is again about kilauea ;>

    The rate of inflation measured at uwekahuna is the same as before this years eruption, so far kilauea has reinflated about 20 cm, 200 microradians, and has kept a consistent inflation from resupply at depth, actually the rate might be even higher than before, one of several scenarios provided by HVO as well as speculated on here by me and others. It is also the one most likely to result in rapid reactivation and/or a large eruption of impressive scale. A number of the eruptions between 1960 and 1975 were associated with much less deformation than this, and the east rift has also been inflating too while the summit has, which means kilauea is not likely about to go into an extended dormancy but rather quite likely to erupt within the next year. However it could be some time before another large eruption happens unless it is a mass draining of the system again.

    Looking at this:

    The majority of eruptions on kilauea started after about 100 microradians, except the 1961 ERZ eruption that was just uprift from this years eruptions, which started after about 250 microradians. I think this years eruption is like the 1960-1961 gap, a big drain followed by rapid reinflation in preparation for another eruption within a year of the LERZ eruption, except this years drain was about 3 times bigger so it will take a lot longer to return to the ‘base level’, maybe about 3 years or so. That might be when new ERZ eruptions start happening, but I think eruptions within halemaumau will probably happen quite often and soon, maybe many times in the next 12 months and some could be quite large in the end. My guess is that the ERZ will reactivate once the summit is capable of eruption on a large scale, with a powerful eruption like 1959.

      • Yes, something like that.

        It could be a good time to say that 1959 was the first eruption after 1955, which happened in lower puna…
        It also happened after a significant magma surge, which seems to be happening now as shown above. It has been 4 months since the summit stopped subsiding, and in that time it has already risen by the same amount as it took an entire year to reach before April this year.

    • You are comparing tilt with length across the caldera. They measure different things. The GPS shows no inflation, and an east-west movement which is still notably different from before the eruption. Kilauea does till have magma: the new DI events show this. This differs from Pu’u’O’o which until last week was still going down: it seems completely drained. There is also slow cooling as the heat reservoir has left. The east rift has some refilling with magma but it is not clear where that magma comes from: probably higher up in the rift, perhaps even as far as Kilauea. HVO has written about the low stress regime along the rift, after the big earthquake, which makes it difficult to maintain high magma levels at Kilauea: less weight (head) is needed to push it into the rift. They expect years or decades with little summit activity, for this reason. But it is not straight forward, since if the exit path has collapsed, the magma still has nowhere to go.

      • The graph I used is the same as the one in that paper I linked to, it does indeed measure caldera width and not overall uplift, but periods of increase in width were followed by eruption on numerous past occasions, and in any case why would the caldera width increase this way if there wasn’t inflation.

        The graph you linked to also shows no increase before the drain, which we know definitely happened and was a long term uplift starting in 2015. The graphs you linked are most likely local uplift gps that measure when the bluff itself moves, and uwekahuna is outside the ring fault so it wont record the magma movements unless they are really large scale. Kilaueas resupply at current is by far the world record, before this year it was at 0.2 km3/year, now it could be 50% higher, maybe even as high as 0.4 km3/year right now (not official though, just based off my picture), but even at that rate it will never receive magma fast enough to make the round rise as fast as it fell during this years collapse.

        • This is the GPS which is used for the length measurement (at least one half of it). The pre-eruption inflation of the second half o April is visible in the motion east and north, but not in the ‘up’ which indeed was centred on the caldera itself.

          • The pre-eruption inflation was a long term increase though, it started a long time back. The graph in the paper from 1956 onwards is the same exact graph as the one that combines all those aspects, the same one that is now showing a rapid recovery.

            The graphs you link to show a smaller scale of deformation, the total drop is on the order of 1 meter, and each line is 10 cm apart, in the main graph it is 2.5 meters drop and 50 cm apart. These are not the same graphs, even if they are at the same place they are measuring different things.

            In any case, HVO puts the graph I used on their easily visible deformation page, the ones you found are only accessible through their map and are not highlighted on said map. This means HVO probably considers the one I found as the most useful graph, and the one that is best describing the behaviour. I might not agree on some things HVO have said, like the volume of pu’u o’o and mauna ulu (both of their numbers are way too small, mauna ulu is more than 4 meters thick…) but I have no reason to think their GPS is wrong…

          • It is the same GPS: the plot I linked is used in calculating the length. One reason HVO presents the length is that it combines two GPS’s and this removes some of the uncertainties. The data is recalibrated after a few days, and so the GPS data may change a bit retrospectively (not by much though). This tends not to affect the length and both GPS’s use the same calibration. Another reason is that rising magma can show up both as inflation and deflation, depending on where the GPS is and how deep the magma is. The length will increase in both cases. But the GPS shows the individual movements much better. To see what is actually going on, look at several individual GPS’s. I actually like the tilt best for single measurements as it shows what the direction of the action is (but it can’t distinguish inflation on one side from deflation on the other).

            Some of the current motion is recovery from the eruption and earthquake (which caused 5 meter of motion!). There is rebound and settling.

          • Really, the main point I’m making is that the graph I used originally is a continuation to the one on that paper, obviously they have used some other techniques since 1956 but the main GPS they show is a direct line from then.
            Regardless of what the signal is actually showing it doesn’t really work on short term, but when that line goes up it tends to end in a volcanic event, usually an eruption. Currently the line is going up, it looks small because the scale adjusts to show the massive drop, but it is actually on the same order as the recovery after 1960 already, only a few months after the eruption ended. The past 5 years saw the line go up a total of 50 cm/500 microradians, about 1/3 of that in 2015 when the pulse of magma pushed out enough magma to cause the first lake overflows, and then that happened again this year and that was when kilauea reached its highest point on the record, and probably the highest it had been since 1924 or even 1840, before dropping about 2500 microradians, and now it has recovered about 200 microradians. On that picture after 2015 there would be a sharp rise followed by a massive drop and then a very sharp rise again, what is happening now is not a volcano going to sleep. In fact here is just such a picture:

            Pretty rough, but as you can see, its pretty obvious something massive was going to happen when you get onto this scale… What is also obvious is how fast things are recovering, the fastest recovery out of all those other eruptions, and it looks to be accelerating slighty at the recent end of the graph. Again, it doesn’t matter what this graph is actually measures, it is tied directly to this long term signal, and thus is the same thing that has responded in that way to previous events. That line going up means things are recovering, very fast… It will take

          • You are extending the tilt plot with length data, correct? In general, that is a very difficult problem. You need to show how they are related, and if there is a clear relation, you need to compute the scaling constant – what value did you use?

            Clearly there was a change from around 2008, where magma began to pile up underneath Kilauea, leading to the lava lake. But in your plot, the total motion ‘up’ is roughly half the total ‘down’ from the collapse and that seems far too much. The collapse was enormous. There is some recovery going on, but it is not at the scale where the collapse would be undone in a year. And we don’t know how much is rebound and how much is refill.

            You can also look at the tilt data: it is available for a month back. None of the ones around Kilauea show significant positive tilt. They are flat to slightly negative (note that you need to look at both angles). It would be nice to have the plots over a much longer period and you can ask HVO whether they would be willing to show you. The one at the volcano observatory is sadly out of operation. (Note that the tilt is measure separately from the GPS – you could in principle get it from the GPS’s by subtracting the two ‘up’ components from each other)

          • Actually the lava lake appeared in 2011, before that it was just some deep set spattering vents that would sometimes overflow, but just prior to the kamoamoa fissure it rose up to become a real lava lake and stayed after then. It mostly stayed deep though, it was only after 2015 that it was consistently high, and that is when the inflation started. 2008 when the overlook vent opened was actually when there was deflation and a temporary lack of supply that lasted a few months, it probably formed through collapse of a shallow intrusion in mid 2007, but whatever it formed from it was not really a major vent for a while afterwards.

            Tilt isn’t going to work that well now at the summit, the shallow system is gone, all the deformation is coming from the south caldera chamber which is 3-5 km deep and partly outside the existing caldera to the south. That will cause gradual changes that are too big to see on that scale. Uwekahuna is also not over that chamber, and there is a ring fault between them to take up the movement. What will show is the gradual movements the GPS shows better, exactly what appears on the graph. The tilt in the caldera will pick up superficial movement caused by caldera settling though, which is still happening.

            Also to make that, I just measured off the scale on the picture already, it isn’t going to be perfect because it was drawn freehand in paint, but even if details are wrong the overall picture is not, what happened this year was on an entirely different scale to the rest of the past 70 years.

          • To put it to scale you need to use the same tiltmeter that is showed in the 1956-1999 figure. I don’t see any signs of imminent reactivation, I am not sure of why the distance CRIM-UWEV has grown, it could be just due to south flank slow slip and that would not be a sign of pressurization. Individually the GPS do not show any inflation, even AHUP and the GPS in the UERZ that are outside the ring fault system and should not be affected by any settling of the new caldera show if anything continuing deflation. There was a fast recovery of the upper LERZ with more than 10 cm of inflation in the 2-3 months following the end of the eruption, magma that I think most plausible came from the summit but as Albert says it could have alternatively just have been a transfer of magma within the rift.

          • After 1960 there was a long period of no activity for about a year, then suddenly a climb with that ending with another rift eruption, after that every eruption has been followed by rapid recharge. Assuming this is different because of scale is not really very sensible, especially when historical precedence in 1790 suggests it might take only a year or two for large scale summit activity to happen after a big LERZ eruption. I think at least some summit eruptions will happen to fill some of the hole, not many but something like in the 1960s.

          • I meant to add that 1960 was also different to a lot of the other eruptions because it started off this current rift episode, while this years eruption has happened at the end of it, or middle… Either way it has precedence and is behaving exactly as would be expected for a volcano fast recovering from a large eruption.

            Yes it is technically true that there are other options that would explain the movement, like sliding, but with this being kilauea with its historically enormous supply rate, and the same pattern being repeated many times in the 20th century on a smaller scale, the most plausible and most likely explanation for this movement is that magma is still moving into kilauea at high rate and is filling the system again. There is no reason at all why the supply from depth would have changed, fissure 8 was deep sourced but that is still only 10 km at most and probably less, far above the depth needed to alter the hotspot or deep feeder, which is between about 80-15 km deep. This eruption has some similarities to 1840, like the rapid onset of large scale activity once new magma started erupting (actually even before fissure 8 took over this years event was as voluminous as 1840 in half the time) and increase in lava lake activity at the summit, and 1840 lead to a reduction in eruptive activity on kilauea, but 1840 also happened when mauna loa was waking up and taking over, something that has since ceased and only happens pretty infrequently based on ages of the lava flows. Mauna loa is not waking up in that sense now, I doubt it will erupt frequently again for centuries, maybe only a few more times before 2100.

    • It did this in 2015 too, but there were no videos of that eruption. This looks pretty intense though, I dont think 1000 m3/s but in the 100s for sure

      • Ambrym is an amazing volcano
        It haves 3 or 4 lava lakes now 4 conduits connected at depth.
        Fluid basaltic Hawaiian activity.
        Ambrym is very much an oversized version of Masaya. Ambrym haves a gigantic caldera feature from a early holocene VEI 6 or 7 plinian event, inside thats is many later basaltic cones and craters and deep pits that holds the lava lakes.

        Ambrym haves a rift system too with many holocene cinder cones and scoria cones.

        Today Ambrym haves a very large magma supply and totaly massive gas output.
        Very impressive for a subduction zone volcano.
        In Ambrym the magma supply is massive and magmas rises quickly from depth, without evolving, Thats why it does fluid Hawaiian basalt activity in a Subduction Arc. Masaya, Villaricca haves similar magmas

  30. Eruption commences at Solputan. Ash to 25K loud roaring reported. Ash height uncertain due to clouds.

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