On the importance of Deep Quacks

Askja III caldera in the background behind Viti volcanic vent. Photograph by Boaworm, Wikimedia Commons.

Back in early 2011 I was sitting down for a late light evening read of “Lower-crustal earthquakes caused by magma movement beneath Askja volcano on the north Icelandic rift” by Soosalu et al. As I read angels started to sing a glorious hymn as I had an epiphany and my view on how volcanoes operate changed forever.

For me this is the single most important paper in how to understand volcanoes, and I have been meaning to write about it for almost 8 years. So, a bit overdue, and with some mighty rambling detours I will describe the paper, the implications, and the current tidings of Askja.

 

The paper

Heidi Soosalu, image from www.karolinafund.com

The paper is straight-forward and easy to understand, it describes the findings of two seismic studies done in 2006 and 2007 of Askja volcano. It was done with 20 seismometers working in conjunction with the national Icelandic network.

In 2006 this highly augmented network detected circa 100 deep earthquakes between 14- and 26-kilometres depth. In 2007 the same network detected more than twice that number, some as deep as 34 kilometres deep.

This was interpreted as short magma dyke intrusions caused by increase in magma pressure, presumably as magma moved upwards.

The earthquakes were not of the same type as the upper crustal tectonic earthquakes, instead they had a lower frequency with a perceived coda produced by reverberations presumably from adjacent magma bodies.

In Soosalu et al they perceived this as short dykes being a few metres long, or as being brittle quakes in hot ductile material caused by increasing magmatic pressure.

After this paper the model was proven to be correct as Askja was seen as partially inflating, a change from the previous state of long-term deflation. This was also found by Hazel Rymer in a study of gravimetric changes.

 

Epiphany and Vivaldi

I remember that I put on Thomas Wilbrandt’s reinterpretation of Vivaldi’s Four Seasons on my Bowers & Wilkins Nautilus speakers and sat down for a think.

As I was thinking about deep stuff I decided to start very deep indeed and work my way up. I started with the Icelandic plume, pondering that it was cyclical in nature, and how that might show itself as and when a new cycle emerged.

Since we are talking about something akin to treacle moving at the speed of an inch per year, I thought that it would be a gradually emerging event moving at glacial speed. Sort of like if a pillow was hitting a foam mattress in slow motion from below, slowly pushing itself up into the cracks and nooks of the Icelandic volcanoes.

Then I started to ponder how that would be evidenced in light of the paper I had just read. And I thought that this would give a very spread out and diffuse amount of deep earthquakes centring around Kistufell, since this is the volcano sitting directly on top of the plume head.

At this point I connected this to another thing floating around in my head. All the volcanoes around the plume head had been erupting magma from the previous plume pulse roughly 250 years before.

Grimsvötn was a stunning example of this, it had been coughing up ever staler dregs after the eruptions it had back around the Skaftár Fires in 1783.

Grimsvötn had then violently changed in 2011 when all of a sudden fresh hot magma filled with large amounts of volatiles pushed out in an eruption bordering near the VEI-5 range. At this moment it all clicked in my head and I felt pretty sure that the magma pulse had started not long before the 2006 survey in the paper I had just read.

It then dawned on me that clumsy me had stumbled on a theory that could be a way to prognosticate something never seen on instruments previously, and that was eruptions caused by a plume pulse, and that if I was correct these deep earthquakes would coalesce on the volcano that was the easiest to break through at. Ie, at the point of least resistance.

This lead me down a two-and-a-half-year long hunt for deep earthquakes in Iceland, much of this was possible thanks to Lurking as he introduced the world to do-it-at-home volcanic plotting as a prognosticative tool.

 

El Hierro

Flaming Restingolitas over El Hierro. Photograph by Stavros Meletidis, IGN. Wikimedia Commons.

As chance would have it, I got to test it against a more unexpected plume pulse over in the sunny Canary Islands as El Hierro decided to become festive.

There we could see initial deep quakes turning into sill-formations as magma pushed itself into the dormant volcano of Tanganasoga, before it all went down into a fissure swarm and erupted harmlessly out in the waters to the south of the island.

I must admit that I at that point did not see this being copied so exactly on a far grander scale two years later in Iceland in such exacting detail.

 

Prior to Icelandic festivities

Holuhraun Baugur vent. Photograph by Joschen Bacher. Wikimedia Commons.

As the eruption of El Hierro ended I turned back to my hunt for deep earthquakes under Iceland with new vigour, feeling that the model I had envisaged would work. Soon enough the earthquakes started to coalesce around a fairly unknown volcano named Kistufell, known to be situated directly on top of the plume head.

In 2013 the activity had increased quite a bit and I was convinced that either Kistufell would erupt, or we would have a shield formation north of it, or that Bardarbunga would erupt, possibly as a rift eruption.

Since I did not want to sound like a crazed loon I discussed this behind the scenes with my fellow moderators, especially Lurking, so that things would be saved for history if I was correct. I also started a rather long-term series of articles about that part of Iceland to give the readers a backdrop to the eruption I by then knew was coming.

Quite a few people starting to wonder if I was off the rockers writing incessantly about Icelandic unknown volcanoes and volcanic features that was doing absolutely nothing in the eyes of the average reader, even though I hinted quite a lot about something being in the making.

As the months progressed, I could refine the prognosis until I could accurately and publicly state that an eruption was imminent. In retrospect this was my 15 minutes of volcanic fame.

Obviously, I would not have gotten it right without having a bookshelf with volcanic papers in the loo, complete with the marvellous paper by Soosalu et al. All honours where due. By the way, am I the only one on the planet with a bookshelf in the loo?

 

Enter the Dragon

Herdubreid trying to steal Askjas thunder as usual. Photograph by Icemuon, Wikimedia Commons.

As things have it the Icelandic national network picked up 23 deep earthquakes at Askja last week at the same NNE corner of the volcano as Soosalu et al described in that paper indicating that once more the pressure is increasing over there.

I should here say that there were probably hundreds of them, but due to technical reasons most of those could not be detected due to the minor number of seismometers in the vicinity.

It was indeed followed by minor changes in the GPS-trajectories. And with minor I really mean minor changes, but they indicated inflation over a wider area tilting the volcano ever so slightly indicating a root-fill episode of the volcanic system.

I should here go into some detail of the state of the volcano. First of all, it is not one of the volcanoes producing high frequency eruptions, instead it goes through episodes of infill causing eruptive sequences interspersed by rather long dormancy periods. Sometimes these dormancy periods last far longer than a millennium, but as and when it has an eruptive cycle it is not uncommon that it goes caldera, something it has done 3 times since the end of deglaciation.

It last erupted in 1961 and has suffered from a long-term period of deflation caused by evacuation of magma, possibly influenced by the Krafla Fires, since the deflation started at that time.

This long-term deflation means that the volcano is fairly depleted of magma and is in a low-pressure state. The rate of deflation was deemed to be around 50 centimetres per year at the caldera centre by Hazel Rymer, a quite staggering amount.

This means that it will take quite some time before the volcano is refilled enough to erupt. It all depends on the rate of the intrusion, and how much of the available plume derived magma that will end up inside Askja in competition with other nearby volcanoes.

Bardarbunga is currently taking up quite a bit of the available magma, so is also Grimsvötn as it preps for its next eruption. Same goes for Kistufell and Trölladyngja, the latter is a bit of a mystery since it officially is a single eruption shield volcano officially not counted as a central volcano. It was though also quite active prior to the Holuhraun eruption from a seismic standpoint evidencing the possibility that it is an emergent central volcano.

To the north-east of Askja you find Herdubreid, a volcano that last had a minor eruption in the early Holocene. Herdubreid has been highly active in the last decade and is inflating as magma is entering the system.

Here comes a problem with the GPS-trajectories, it is a very noisy environment with all these volcanoes acting on the stations at the same time as tectonic swarms alter things, and at the macro level you have the continental rift running through it all.

Now combine that with the after effects of the Holuhraun eruption and you need to be the Gandalf of all things GPS to be able to divinate minute changes caused by Askja, and up until now nothing has been possible to see, and even now it is so minute that it is hard to state where and what is happening at Askja. All we can say is that something seems to have happened.

In the end Askja is a very big volcanic system, even for being in Iceland. It also tends to go for big eruptions instead of frequent eruptions. This means that it will take quite a bit of magma for it to erupt.

On the other hand, we are in the middle of a plume pulse with prodigious amounts of plume derived magma arriving into the Icelandic volcanoes, and if a sizeable portion is going up into Askja it could be cocked and ready to fire quickly.

Right now, we are looking at about a decade of inflation, with not much showing for it since the system was low pressure at the beginning. And until we start to see larger swarms, we know that the pressure is not high enough for an eruption to be possible.

Question right now is if that will happen next year, or in a millennium?

The answer is that unless the amount of magma entering the system increases rapidly, we are in for quite a bit of a waiting game.

A couple of weeks ago I was asked if the eruption of Holuhraun would have any influence on Askja. The answer to that is that it is highly unlikely. Holuhraun was a distal eruption caused by a rifting fissure.

The last time that Holuhraun erupted was in 1797 and it took 85 years until Askja erupted, so at least back then it had no effect.

Anyway, Askja is indeed doing interesting things and it is on a runup, but it is still a bit early to say when it will be interesting enough to erupt.

CARL REHNBERG

http://www.ene.ttu.ee/maeinstituut/artiklid/2011/Soosaluetal10.pdf

http://www.norvol.hi.is/pdf/2005_deZeeuwvanDalfsen_Rymer_Sigmundsson_Sturkell.pdf

https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3121.2010.00948.x

 

 

230 thoughts on “On the importance of Deep Quacks

    • Nope, I meant to write Quacks.
      It comes from a certain professor of volcanology who pronounces earthquakes as Earthquacks. And the blasted thing is stuck in my head more than 10 years later, I often stagger when trying to pronounce earthquakes in a normal fashion to this day.

    • Also, these deep earthquakes have a look of a quack to them due to the spectral coda.

      • Strangely I have never been able to directly reply to a new post.
        Anyway, yes of course doesn’t everyone have a shelf of reading matter in the loo?
        Nerdily mine is New Scientist and Scientific American.

        • Mainly Viz magazines with the occasional kids story book that nearly ends up being posted into the bog…

        • I dumped SciAm since they kept adding syllables to my last name. At 3 I told them to pack sand.

          • I am now freely admitting to being curious about what syllables they added and where. I probably have to much imagination and to much spare time on my hands.
            Or, I am procrastinating as usual.

          • It will be in the back channel tomorrow after I get the dog measured and poked at. (He doesn’t know it yet)

  1. It hardly seems like anything is happening at all in Iceland at the moment. Can’t recall anything particularly notable in the last 6 months. The 4-year non-eruptive gap doesn’t seem likely to end anytime soon… In saying that it isn’t that surprising considering there have only been 8 eruptions since Krafla’s last one. Almost seems too quiet! Will there be a sudden flurry of eruptions or only a subtle increase? Will there be a complete surprise? Will Brexit actually happen before the next eruption? Is the source of Icelandic eruptions really a duck?! These are the big questions…

    TL;DR: I have nothing to contribute.

  2. Thanks for the catch up on Iceland…. something better happen there soon… or the grocery checker will think i’m a quack.
    i like the duck comment…
    Best!motsfo

    • Odd, when my grocery checkout clerk asks me how I’m doing I cheerily respond “Like shit, Yourself?” This usually puts them on their heels because stating “The Same” would get the ire of their manager. Usually I just get a giggle. 😀

      Note: For maximum effect, you have to be as upbeat and cheerful as can be. If not, they just think you are a bitter and grumpy old person. Ideally, your outward attitude should not matching what you just stated. Be as courteous and as polite as you can be… that will leave them wondering what just happened for the rest of the day.

      …Oh, and be sure to use the honorific “Yes Sir or Yes Maam” as appropriate, especially if they are younger than you. That torques their brain quite a bit and is a good touch to end the encounter. In the deep south, that is customary when talking with someone in authority or older than yourself. Since they are the clerk, it only makes sense to be deferential to them since they are your official interface with the store. (Well, that was the line I used when a young girl in her early 20’s took issue with me calling her “maam.”)

      We may not have as formal an interaction ruleset as the Japanese, but we can at least have fun with what we have right?

      Note: I can get away with this because I am very greyed.. borderline of being white haired. I discovered this at my last haircut on the ship. I looked down and saw what appeared to be little tuffs of chaff on the cutting apron. To my horror, it was my hair.

      Chaff: A decoy material used to cause false targets. It can be the consistency of tiny strands of grey hair.

  3. This is an amazing article Carl!
    Thank you alot.

    Was Grimsvötns 2004 basalt ash compositions diffrent from 2011?
    More crystals in 2004 and 1998 ?

    • It was a mixture. Some of it had cooled further than any Grimsvotn magma since Laki, so that was the stale stuff. But there was also a new component which appeared to come from a recharge of the 15-km magma chamber. Possibly the same recharge that later caused Holuhraun. It would be the first fresh magma into Grimsvotn since Laki.

      • 2011 seemed extremely fresh from the mantle
        Just as Holuhraun was
        Holuhraun was almost 1200 C making it the hottest Iceland eruption so far caught on camera.
        Grimsvötn likley similar for 2011 s magmas

      • Albert is correct. And the mixture changed as the eruption went on. As it went on the mixture favoured fresh material more and more.

        In the broader scope it was most likely due to the ongoing magma pulse that also caused Holuhraun and is causing the ruccus at Herdubreid, and the refill at Askja.

        • 2011 was likley 1200 C below the gas nucleation depth in the conduit
          A crystal free thoelite basalt fresh the the plume source
          Grimsvötn is strongly thoelitic due to the high ammounts of partial melting under Vatnajökull
          If partial melting is high enough picrite basalts can form too as they can be found in Iceland rift zones

          Holuhraun was also very strongly thoelitic another sign of a high level of partial melting, it was hot too 1185 C

          • The 2011 ejecta contained 5% of crystals. It was not crystal-free

          • What temperature was it
            At least 1170 C right?

            Below 1100 C It turns into crystal rich melt

          • The temperature that is derived from crystals is the temperature inside the magma chamber. It is NOT the eruption temperature.

            For the 2011 eruption the ‘crystal temperature’ was 1110 C, and it had cooled by 0.1C/yr for 200 years. That applies to the part of the magma that crystallized. The ‘new’ magma is not included.

            The eruption temperature is not very meaningful for 2011 as little lava was produced. It was mainly tephra, and the decompression during the explosion causes fast cooling.

          • Im pretty soure 2011 was hotter than 1110 C here is my own opinion
            Im pretty soure Grimsvötn 2011 was much much much hotter than 1110 C in the magma conduit gas nucleation bubble froth level. As I told before 2011 was completely crystal poor ash and lava pieces as far as I knows. A crystal poor basalt cooled very quickly and.. was very hot at birth. The huge gas content and few crystal nature suggest a very fresh origin for the 2011 materials.
            Grimsvötns magmas are formed by very high levels of partial melting
            And are strongly thoelitic in nature.
            Holhuraun at 1185 C had similar crystal contents if not even higher
            yet at much hotter than the numbers you propse for Grimsvötn 2011.
            Holhuraun at 1185 C had quite alot of crystals
            yet grimsvötn 2011 at 1110 C had almost none, doesnot sound logical at all. Strongly thoelitic magmas like Iceland and Hawaii haves high temperature requirments to be crystal poor

            ( my own opinion on 2011 temperature in the conduit just before when the gas blows magma to pieces is around 1200 C to explain the crystal poor nature of the ash glass shards ). The extremely quick cooling in 2011 explosive ash fragmentation preserves the original 2011 Grimsvötn magma composition very well.
            2011 basaltic ash and materials had almost all minerals melted at Norman L. Bowen series. This is often the case at 1180 C
            reaction mineral seriers for that Grimsvötn magma and that requires little above 1200 c.
            2011 likley asceded quickly from the deeper resovair in Grimsvötn and erupted with force.

            Crystals in erupted magmas are often very small ( erupted rocks are fine grained cools quickly )
            Had the 2011 magma been 1100 C there woud be numerous small phenocrysts ( tiny crystals of olivine and alot other plagioclases ) under the microscope in the magma. 2011 that was not the case, it was almost pure glass with all the minerals molten at start. ( at 1100 c many basaltic magmas contains alot of crystals, 2014 Pahoa viscous pahoehoe flows was a coarse crystal mess at 1130 C where they stopped ).

        • Holuhraun was the hottest Icelandic eruption so far got in camera.
          Holhuraun at 1185 to a maxium of 1195 C in thermal measurement by IMO was just cool enough to produce some tiny crystals of olivine in the melt but otherwise no other crystals.. this is why Holhuraun was so fluid.
          Hot and low 49% sillica and few crystals.
          Very fluid was Holuhuraun.
          Im supprised of the rather grey colour of the houhraun basalt despite its low sillica content, coud be a mineralogy thing.
          I expected to be almost black

          Its worth to notice that Holhuraun magma spent some time underground and cooled a bit. The orginal Holuhraun magma was likley chemicaly identical to Grimsvötns 2011 batch with no crystals at all

        • Holhurauns 1185 C to almost 1195 C are pretty much good proof that Icelands hotspot is quite hot. Holuhraun was the hottest Icelandic eruption seen by cameras so far. Thats why it was so fluid, baugur boiled like an upset foamy sea in September 2014.
          The magma that was intruded from Kistufell was likley even hotter than the already hot lavas in bardarbungas chamber.
          Im also curious on your comming article on Mauna Loa what you haves to say there.

        • Carl : D did you knew that I haves a jar of Grimsvötn 2011 ash?
          Bought from volcano huse Iceland.¨
          The very mafic basalt 2011 ash is pitch black almost and fine grained and smooth in the hands. It looks alot like black powder.
          To prove my theories Im prepared to melt a little of it… in my furnace at 1185 C and 1110 C and then take it out and instantly cool and look under microscope for crystal formations when I can get my furance and right equpment fixed again.
          Im pretty soure at Alberts 1110 C its a crystal mush thats not like what seen in 2011

          • Don’t forget to do this under a pressure equal to that in the magma chamber, i.e. underneath some kilometers of rock. Or better not: high pressure vats are dangerous beasts, only for the professionals with reduced life expectancy (universities would like to spend less on staff pensions). If you do it at room pressure, you’ll get different results.

      • The Kaku stale dough in Askja will be found inside the main crustal magma chamber where the rising basalts diffrentitate into Ryholites.
        But I guess much of the current Ryholites in Askja where evaculated during 1875 eruption
        Likely not much eruptible ryholite for now inside Askja

      • If the next Grimsvötn eruption becomes even hotter and more crystal free
        Then the plume pulse is a confirmed theory!
        Im waiting for stinkvotn to blow again and analysis of the ash glass

      • Carl do you agree with me on Grimsvötn 2011 tephra?
        I knows some serious geology too but this is just an opinion from myself on Grimsvötn 2011 tephras.

        Albert coud very very much be correct about the low 2011 ( 1110 C temps )
        Its a bit supprising if thats a reality thats same temps as Etna when she is fresh

        • Albert is correct, and debating the eruption temperature is a rather moot point since it was barfed up through 700 meters of water and 500 meters of ice.

          • Carl I meant the Grimsvötn eruption temperature inside the conduit dyke below gas bubble nucleation depth
            It must be hotter than 1110 C for souch crystal poor and very very mafic basalt
            I suggest around 1180 C at least
            Grimsvötn 2011 is similar in compostion to Iki 1959 lavas
            2011 was one of the most primitive and mafic basalts Iceland so far

          • If next Grimsvötn Eruption coughts up even more crystal free melts and same very mafic basalt trend as 2011.. the plume pulse is indeed confirmed.
            The 2011 is already good proof

          • Are you soure Carl that Grimsvötn 2011 was only 1110 C in the deep conduit? Souch crystal poor and mafic basalt should be much higher in temperature.

            what was the temperature of 2004 and 1996 then underground
            Im very curious

          • Those where less warm.
            I should though state that basing temperature in conduit by crystal percentages is a bit iffy when you are talking about a system like Grimsvötn.
            You have mantle derived crystals (garnets) that form at extreme temperatures, you have cooling crystals formed in situ in chamber, you have xenolith crystals formed in crustulorum (latin for bun) and so on and so forth, all of this can in turn be mixed into hot fresh material.

            So, I do not agree with neither you, nor Albert, for the simple reason that no intrument has given data about it. I am well and truly an “instrumentalist” on this.

          • The crystals give the temperature/pressure where they formed. Now eruptions may not source all their ejecta from the a uniform chamber. In fact Grimsvotn didn’t: it had recently acquired a secret stash of hotter magma. Once the cold stuff was out, it changed to a hotter personality. There may be a bit hotter magma to come.

          • Here: official temperatures. 2011 was around 1120-30 C, though some of it was even as low as 1075 C, with some similarities reported to samples from Saksurnavatn. The eruption was more evolved than Holuhraun, near the upper end of basalt (as I would expect). It also gives a higher eruption size for the 1873 eruption- 0.5km^3, so very similar to 2011.

            https://hal-clermont-univ.archives-ouvertes.fr/hal-01713309/document

          • What does this analysis give for ash erupted in 1783? I would expect lava erupted out of laki would be different slightly to the lava erupted at grimsvotn but if that stuff was really fresh out of the mantle then it was probably very hot and much hotter than those temperatures for 2011, something more similar to holuhraun or most of kilaueas recent lavas especially 1959 and 2018 which were over 1200 C at some points.

  4. For those who thought that Mayotte was erupting…
    Eruption started a couple of days ago according to the seismometers, finally the GPS trajectories are in accordance with what everyone said happened half a year ago… Sigh.

        • Is it even in shallow enough water to be able to affect the surface? (If it is indeed erupting- could be a while before official confirmation!)

    • GPS trajectories have long been in accordance with an eruption.

        • In the last post you explained your model where the deformation of the GPS was due to dyke intrusion giving a distal effect and then I asked why would the model of Pierre Briole, author of the 2018 publication in french be wrong: Deflation of a deep magma body causing the deformation, intrusion from May to July, possible start of eruption around July 10 and continued effusion up until now. The question was left unanswered.

    • Hi everyone,
      Luke here. Been hanging around for a while, following your discussions and admiring your knowledge. Didn’t feel the urge to join.
      But now I got a question:
      @Carl: How come you’re saying something’s changed in these plots a couple of days ago? To me, the plot only shows a change somewhere around May 2018.
      What’s the red line anyway?
      I have to say, I’m an educated beginner.

      Welcome! The systems puts every new commenter into a holding queue (the ‘dungeon’), for approval. Once that is done, further comments should appear without such delay. – Admin

      • That is a really good question Luke.
        Normally that is an averaged line over a set period of time. Here it is not, and I have not been able to find an explanation for it either.
        My best guess is that it is a leveling line measurment. But I freely admit that I am probably wrong.

        • Carl, don’t misunderstand me. I don’t dare questioning your argument. I just don’t see the change in the plot. What are you looking at?
          Just trying to learn.

        • The red line is a fit to the ‘north’ movement. It only applies to the middle panel. The parts before and after the onset of the magma movement were clearly fitted with the same wiggle (and same amplitude(, but inverted and shifted. You can see from the fact that the wiggle has alternating higher and lower maxima, that it is actually a sum of two wiggles, one twice as slow as the other.

          For the other panels, they did a similar fit but now the procedure failed rather dramatically, because you can’t use the same wiggles before and after. They are entirely different functions. That is what you get with automatic routines.

          Regarding Luke’s question, the initial GPS trajectories showed that magma was on the move, and probably went a considerable distance. It could have erupted but there were no other signs of that. The points from the last 10 days (I assume it is one point per day) show a very different behaviour. But it is possible that they still need calibrating. GPS measurements can be improved if you know the exact position of the satellites. That model is normally run a few days later. In Hawai’i too, the GPS points can sometimes be changed after a few days.

          As to how Carl knows the eruption started, I must admit ignorance. He probably ran the seismographs through this speakers.

          • No fish entrails, nor quixotic speakers, was involved.

            If I have time I will write an article about it. But probably no article from me this weekend.

    • Do the quakes give any indication of where this probable eruption is? Im assuming it is deep underwater but if the quakes are instead showing a rising intrusion under the island itself that is a whole different story and i guess we will find out soon…
      Mayotte I think has erupted several times on land in the holocene and last time about 3500 years ago, it is probably in a similar stage of life to the old hawaiian islands like oahu, while karthala is like kilauea and very active though the comores track is a lot less direct than for hawaii.

      • There is to the best of my knowledge no public seismometers available, and I have looked like crazy. The nearest available is a station at Kilimanjaro.
        I guess the french send their data via radio-link and not via ip.

    • https://www.emsc-csem.org/Earthquake/earthquake.php?id=754109#summary

      Magnitude mb 4.6
      Region MAYOTTE REGION
      Date time 2019-03-28 01:40:06.9 UTC
      Location 12.82 S ; 45.30 E
      Depth 10 km
      Distances 9 km SE of Mamoudzou, Mayotte / pop: 54,900 / local time: 04:40:06.9 2019-03-28
      255 km SE of Moroni, Comoros / pop: 42,900 / local time: 04:40:06.9 2019-03-28
      716 km N of Antananarivo, Madagascar / pop: 1,392,000 / local time: 04:40:06.9 2019-03-28

      There are a considerable number of felt reports under Testimonies above.

    • On the static map you can now use the depth slider to isolate quake within a depth range

    • Zoomed out on the second one to see the whole area. Very cool.

      The area to the north around Grímsey island is pretty active too.

    • Three holders… Is that for three different types of bog roll? 2 ply, 4, ply and eiderdown?

      • In the Military, toilet paper is not typically categorized in ply. It is best described by Grit.

        • Grit! Brilliant! Will remember that.

          Ever unimpressed by stupidly expensive speakers, I build my own enclosures to suit the location. If there is one thing you ought to do to improve your sound system its have active crossovers and one amp per speaker unit. This for a whole lot of good technical reasons. Modern switched mode amplifiers are exceptionally high quality and absurdly cheap. MY current rather modest system has 5 units and 5 amplifiers with active crossovers.

          Once off the budget speaker units its all marketing and no improvement but it does impress the ignorant.

    • Two comments, I bought them on a bankruptcy auction. But if not available cheaply I would have bought them, or another set with equal measuring data. Because I need them more than I need a red two seater sports car.

      Secondly, since I am an acoustics boffin working professionally with sound (of sorts), I can attest that unless your name is Nelson Pass, you can’t build enclosures tracking like these ones.
      Are they worth the dosh? Nope, not at all, unless you are insanely into hifi, music, or acoustics and willing to spend the same amount on Hihi as regular middle aged men do on red two-seater sports cars. Or they spend on unobtanium fishing rods.

      For me it is simple, I need a reference system for my work, I got one.
      And for boffin-reference, I once used the actuators from a small space-craft to build a chair that could emulate the vibrations of earth rumbles to better understand volcanic eruptions and seismology.

      • Middle aged men get much more from red two seater sports car, full 100% bang for your buck, most MAM (middle aged men) cant even hear most of the frequencies those speakers put out.

        Lesson, buy sports cars not speakers

        • Ahh now there I have to disagree with you.
          I think I qualify as a “Middle aged man, being as I’ll be 56 in a few weeks time.
          I’ve experienced the power of high performance cars… And it’s ok.
          But only ok.
          However, as a keen amateur home recorder of music and sound, utterly reliable, honest (bias free or even just bias reliably known) reference speakers are absolutely essential. The more accurate the better.

          I’d take the speakers every time if I had that sort of money.

          • OK

            This is so off topic but I have to chime in again.

            I am an avid fisherman…fished in the Arctic (my personal record is a 45lb lake trout) no fly fishing, too much work

            Have a great set of speakers, not top level but medium, enough to shake things off the walls

            I own 480hp of V8 muscle, a convertible with a subwoofer in the trunk.

            If I had to give up one of the above, there is no way the car goes. * if it wasn’t a convertible, maybe the car goes and the sound system stays

            😀

          • Be careful in Neptune Beach Florida. They have an ongoing war with Seismicly Acoustic cars.

            (South of Mayport near Jacksonville)

        • Now all we have to wait for is for one of our fly-fishing aficionados to chime in on how utterly ridiculous both the car and speaker MAMs are.
          I have no doubt we will get a lecture on the joy of using a boron-doped buckminster-fullerene fishing rod.

          • I don’t fly fish. My last rod was a solid core saltwater rig. The only thing I wanted from my rod is the ability to not auto disassemble while fighting a mackerel.

            But I gave up on that hobby. Friken pelicans piss me off. Catch one on 35 pound test and you’ll understand. A fish leaping from the water while fighting is cool, but a pelican flying off with your bait is a different matter.

      • Oh, don’t get me wrong – if I win the lottery, I’ll be buying them!

        I’ll put them in my music room in the opposite wing of the mansion from my dual Digital Laser IMAX 3D /IMAX 70mm tv room – as that comes with its own twelve channel surround system I’m told.

        • With or without available dosh I wouldn’t buy any of these. I have no interest in impressing anyone, not even myself. I might buy some lessons allowing me to do time speeding round a racetrack (or do insane things in a plane) and I might go to some live gigs (but after 1964-75 why bother?).

          As for thrills in general many good ones are available at your local theme park, although most are rather unimpressive once you get on.

          • Volunteer Firefighter is a good way to get an adrenaline fix.

            (Make sure you get any and all training that is available) that helps to keep you from getting dead.

  5. Excellent article, Carl. I note though that your comments (as well as others) are stressing magmatic inflow as a principle causation for inflation under Askja. However, is not also possible that there is rapid remobilization of crystal mush going on? There were several papers on the subject with the most notable being Rapid Remobilization of Magmatic Crystals Kept in Cold Storage (https://www.ncbi.nlm.nih.gov/pubmed/24531766), which was referenced in a recent (Dec. 2018) Scientific American “article” about Laguna del Maulle and it’s potential to rapidly remobilize it’s sizeable cold storage chamber and erupt to near “supervolcano” levels. The jist of what I’m saying is that maybe it’s not so much magmatic inflow (there is some, fer sure), but rather sudden heating from below that’s causing the upper magma chamber to remobilze/melt thus increasing pressure?
    Just a thought…

    • I love it when people come with a really bright comment.
      This one deserves an entire article to go in depth of it.

      At Askja those remobilizations happen, last time it did was 1875. But since this is really volatile magmas to begin with, and the magmas are hotter than usual, you get explosive remobilization in a very rapid manner.
      1875 probably went from the inital intrusion to explosion in hours, if not minutes.

      But, your darn comment need an entire article to be answered better. 🙂

      • Geee, thanks! Would really like to see your thoughts on the subject….since it’s been the knowledge that I’ve gained reading VC that I even became curious.
        Referring to the SciAm article, I was astounded that the potential re-mobilization rate could (in theory) activate a reservoir the size of Yellowstone (or to a smaller extent Laguna del Maulle) in a matter of decades..and as you mentioned, activate smaller magma chambers in much shorter times. Also, there are different mechanisms for the re-activation depending on whether the volcano/magma chamber is subduction-driven or sitting over a mantle plume. This makes me think that while the article focuses on this Chilean time-bomb, there may be some value in better understanding how Iceland’s volcanos eruptions are triggered as well…and there may be few on the planet who would know better than you.

        • Forgot to add that in both models of re-activation, crystal formation/phase change leading to volatile release and heat transfer are key elements to the pre-eruptive process of magma reactivation.
          Maybe Albert might have some further insight on these mechanisms to dovetail on what he already wrote earlier on crystal formation and their relation to time/temp/and pressure that would be needed to form?

          • Urrrp, I meant “crystal melt” not “crystal formation”. Damn wish you could make typo corrections!

    • And if you do, cover yourself well in Katsup for the dragons.

  6. Askja was very active in 1920 s and produced many small thoelite flows in the caldera
    Including a larger event on the south side I think
    he Askja volcano erupted a few times in the 1920s.
    1919, 1921, 1922, 1923, 1924(?), 1926, 1938, 1961 its been small eruptions there

  7. National Geographic appears to be a keen follower of VC! This adds more on the events of 536 and after.

    https://www.nationalgeographic.com/culture/2019/03/ancient-garbage-dump-elusa-reveals-surprising-city-collapse/

    Although I can’t help but point out that there was also a big drought in the area, which started a decade before the first volcano went bang. Also, it seems very unlikely that volcano was in Iceland. They should have read VC a bit better..

    • They recently noinked wildly from my articles about how boring supervolcanoes are. I wish they had quoted me at least, or otherwise referenced me.

      • Africa where a huge mantle plume is decompressing and finding its way into a rift
        Is the place for the next LIP event
        There have already been an earlier LIP in Etiophia as Afar Plume surfaced
        Now we are waiting for the real show, but as large as Pangea Basalts it wont likley get
        This is effusive VEI 8 events

      • This is usual. Reporters just steal or worse, miss-credit. One of my ideas got a full front page in the Grauniad and I wasn’t even mentioned. That’s the beauty of the internet, ideas can get stolen all over.

        • …Grauniad; you must be a Private Eye reader, Farmeroz. Chapeau.

          Can anyone tell an ignoramus such as me if the recent swarms in the Tjornes fracture zone are tectonic, magmatic or both? They appear to be very shallow.

          Cheers, now.

    • Sillica Rich explosive Supervolcanoes are boring beacuse they never do anything
      Yet its still so much hysteria over dead-llowstone and Michios dough inside
      But for soure large resurgent calderas like Long valley and Taupo and Flegeri is fun fo soure.
      The only VEI 8 eruption I wants to see is a basaltic lava flow = Flood basalt
      the larger the more fun

      Africa where there is a large mantle plume is rifting and decompressing is able to generate enromous ammounts of thoelite basalt magmas
      African Rift coud be the next arera where the nexst LIP happens
      African Superplume is not at all as powerful as Pangea Superplume, but its still mighty.
      Im very supprised there have not been any large basalt eruptions in many km3 range recently in Africa

      • Jesper you are rambling on a bit! Anyway, wishing for a catastrophe is not really agreeable. A moderate eruption from one of the Basin and Range volcanic fields (where there isn’t a large population), sure, or minor activity at lesser-known volcanoes in say Alaska or Kamchatka, but not a FB! The individual events on their own would be disastrous!

        • Terrfying and amazing
          Must have a timemachine😏😏
          Now Imagine the very largest flood basalts
          Like largest flows from Deccan and Siberian Traps and Opening of the Atlantic.😁😊
          Imagine single lava flows the size of Scandinavia and UK for worst cases

          Souch individual flows coud have volumes of 7000 to 17 000km3 or larger!. This is a VEI 8+ effusive eruptions. In the most scary examples you can have fissures ( 300 to 600 km long ) Some old dykes in earths crust are many 100 s of kilometers long some over 1000 for old Canada LIP dyke swarm I think. These fissures with huge lava fountains roaring kilometers high all over its lenght. Lava flow rates like the biggest jökulhlaup you can ever Imagine.

          Beacuse major LIP flood basalts caused global warming and Mass Exctiontions
          We can be pretty soure they went on very fast with collossal gas output.
          and the media image of magmageddon is likley quite true.

          Generaly true flood basalt lavas, are thick and uniform and massive: No lava tubes or small scale lobes: its fast and massive.
          A true massive ( 1000km3+ ) flood basalt
          Is likley a huge oversized channelized Aa flow
          With fast smooth Leilani like lava channels
          Flowing like mad crazy it must have done
          In the largest chase these channels coud be many 1000 km long and maybe 100 km wide. Some lava flows from Deccan Traps flowed 1500 kilometers from their vent sources.
          The CAMP lava flow fields extended for over 5000 km over Pangea. It makes Holuhraun look like a little fart.

          At the distant edges of the ( +1000km3 ) Roza and ( +11 000 km3 ) Rhajamundry flows you likley have a massive wall of Aa lava moving quite fast 40 meters high and with some mouch faster breakouts that happens at Aa edges
          Or where the main flow front breaks thrugh the rubble.
          Behind the flow fronts is the main flow and open lava channels that looks like a lava sea from Closeup. The open lava channels goes up to the vent rift systems far away.

          The nightglow from these LIP events must soure been impressive red skies for 100 s / 1000 s of km photographers dream
          The initial startup of a (+ 5000km3 ) flow must have been an impressive sight for soure if its in the fast model the start up itself may generate A few VEI 7 volumes of tephra.

          But we all woud choke and sulfur smog everwhere and mass starvation
          If I gets it, I gets more than I can bite in
          Maybe its better that Flood Basalts are not Todays news

        • 🎶🎵🎶🎵 the Flood Basalt superplume magmageddon dances on the table 🎶🎵🎵🎵🎶🎵

        • For the Basin and Range, I’m surprised there hasn’t been more activity with how thin the crust is getting.

          • Activity is very episodic (rift episode(s)). Last time was Markagunt Plateau in 1050 followed by San Francisco Field in 1085 and Uinkaret in 1100. Then around 1300 was Black Rock Desert and nothing since then. Before 1050 the last eruption in that region was Zuni-Bandera in about 1170 BCE.

  8. OT…. collecting accurate data is very important… keeping an open mind about unknown influences is also important. for example: Hubby comes into kitchen (i’m baking bread) and asks… “Were you running the hot water.” humm me: “Why do You ask?” he: “Because this sink is warm.” (sink is stainless steel and facing a window to the west and it’s 4pm) “nooooooo”, i put my arm around him reassuringly and looking out of said window say. “It’s the sun, or the dragon of the north.( re: Erik the Viking) ” those of You married to Norweigns will understand.
    Best!motsfo

  9. Kilauea has returned to sleep….

    The mountain’s status has returned to Normal.

    Remarks: Current state of the volcano

    Kīlauea Volcano has maintained a low level of non-eruptive unrest since the end of the lower East Rift Zone eruption and summit collapse in early September 2018. The past nearly 8 months without active lava at the surface of the volcano marks the longest time interval without eruption since the 17-month period between November 1979 and April 1982.

    The total combined sulfur dioxide (SO2) emission rate from the summit, Puʻu ʻŌʻō, and lower East Rift Zone fissure vents is currently less than 100 tonnes per day, well below pre-2018 levels.

    Seismicity remains relatively low and steady across the volcano. Although weekly earthquake counts are elevated above pre-2018 eruption levels, they do not reflect shallowing of magma that typically occurs prior to eruption outbreaks. Most of these earthquakes are aftershocks of the May 4, 2018, magnitude-6.9 Kalapana earthquake, and they will continue at declining rates. Earthquakes such as the March 13, 2019, magnitude-5.5 south flank event reflect ongoing south flank instability and are not a sign of renewed eruption potential.

    Ground deformation continues, but at rates below those during the period of major eruptive activity in 2018. Deformation rates on the East Rift Zone and at Kīlauea’s summit are still higher than they were prior to April 2018, but have been slowly decreasing. The middle East Rift Zone between Puʻu ʻŌʻō and Highway 130 continues to show ground motion that likely reflects slow refilling of the deep rift zone. Deformation rates may remain high, as magma entering Kīlauea’s system is stored, rather than erupted. Motion on Kīlauea’s south flank is higher than before May’s magnitude-6.9 earthquake. This motion is consistent with increased sliding on Kīlauea’s décollement fault in a process called “afterslip,” which is expected following a large earthquake.

    What is next at Kīlauea Volcano?

    Since the early 1800s, when written records of Hawaiian volcanoes began, Kīlauea has had infrequent periods during which no lava erupted. The longest known eruptive pause was in 1935-1952, ending with eruption in the caldera.

    Neither this 17-year pause, nor any other shorter pause, followed partial collapse of the caldera such as the collapse that occurred in the summer of 2018.

    After partial caldera collapses in 1840 and 1868, lava returned to the caldera within days to a few weeks. The length of the current pause already exceeds those earlier post-collapse pauses.

    Following partial caldera collapses, the first eruption outside the caldera took place on the East Rift Zone 17 years after the 1823 collapse, on the Southwest Rift Zone 28 years after the 1840 collapse, and on the Southwest Rift Zone 52 years after the 1868 collapse.

    On the basis of these observations, we think it most likely that the next eruption of Kīlauea will take place in the caldera within a few years, and that the next eruption on one of the volcano’s rift zones will be in a decade or longer. This prognosis assumes a return to Kīlauea’s general style of behavior for the past 200 years.

    There remains the possibility that Kīlauea’s behavior may return to the dominantly explosive 300 years preceding the early 1800s. Monitoring and ongoing analysis by HVO may be able to determine in advance which style of behavior will eventually prevail, but it is currently too early to tell.

    Importantly, current monitoring data do not suggest a return to eruptive activity or summit collapse in the coming months. However, Kīlauea is one of the most active volcanoes in the world, and additional eruptions will occur. Residents should remain informed of the volcano’s status, learn about long-term hazards, and understand how alerts and warnings of volcanic activity are distributed.

    • ‘Returned to sleep’ is an interesting way to put it when kilauea has actually been actively erupting for more than half the time since 1952.

    • For now it is sleeping. I however don’t think the ERZ will remain dormant for such a long time, the past large partial collapses (1823, 1832, 1840, 1868, 1924) all took place during a period when events in the rifts were rare and summit activity continuous. Since Kilauea emerged from its longest dormancy period in 1952 activity has been centered in the ERZ even though the 1924 collapse (Halema’uma’u crater) was never entirely filled. After the 2018 eruption ended reinflation of the ERZ resumed and the summit kept deflating, I have interpreted this as a sign that dominance of the ERZ will continue through the next decades and an eruption there could be expected in the next few years though there could be a summit eruption meanwhile. Of course there is no sign of eruptions in the coming months and it remains to be seen if inflation of the ERZ will keep going.

      • Sleeping is a bit overstated.

        There are lots of deep “quacks” that continue from 10km to 30km spread out all over the area under the big island of Hawaiʻi.

        Not sleeping, just re-grouping for the next time…whenever that is. More than likely the exact timing and location be a surprise.

        • No Hawaii haves not a 21km3 supply every year to its 3 active volcanoes
          Hawaii woud go crazy if that was the case

      • I would suspect the next ERZ eruption will be preceded by summit eruptions though, if there was somehow no summit collapse during 2018 but the rift kept inflating because of the initial downrift intrusion (I guess a hypothetical situation where the may 4 quake never happened so it was just the initial intrusion) then probably the area would have already erupted by now and become a stable long lived vent near heiheiahulu but it will likely take several years at least before another sizable ERZ eruption takes place after such a big drain out as last year, over 1 km3 of magma. 1955 was followed by 4 years, and 1960 was followed by 5 years until proper large eruptions took place afterwards (in 1959 and 1965 respectively). 1975 quake took 8 years to recover from, with the shield building characteristic of mauna ulu resuming at puu oo afterwards quite perfectly with how long it would take kilaueas supply to refill the 1975 quake space. Doing the same for now reflecting on the may 4 quake last year predicts an eruption like puu oo could occur in about 5 years at heiheiahulu or nearby, meaning in about 4 years now.

        As I pointed out earlier though probably a lot of times the bottom of halemaumau is actually at the same elevation above sea level as the rift zone where the 1977 vents are, which is the area in question that is recovering quickly. There is open magma down past puu oo but it has to be at least pretty deep to not just leak out everywhere, probably between 2 and as deep as 6 km, nothing less than that though because no SO2. Halemaumau is probably only about 1.5 km above the top of the magma column now, enough to reduce SO2 but such a massive hole surely will not be ignored even in an otherwise ERZ dominated eruption cycle.

        Whatever does happen though it will definitely not go unnoticed, the deep system has been very active recently and based on several larger quakes a large pulse of magma is most likely on the way, it might take years to appear but last time a similar situation to now happened was after 1955, and 1959 was a real monster of a summit eruption. To put it straight, if the 1959 pulse didnt intrude most of its volume into the east rift in late december and over the new year then that eruption in kilauea iki probably would have gone full blown basaltic plinian on the same scale as 1790 or even the massive eruptions around 600 AD (1959-1960 total volume of pulse is 0.07+0.2*+0.15 = 0.42 km3 of magma, which could have been a small VEI 5 if it was all tephra). While now the east rift is even more open than it was in 1960 (meaning a big pulse would very likely go there before all of it blows out the summit) I would expect that with no gas release vent anywhere on kilauea anymore and a lot of new magma on the way things will get quite lively in the coming years.
        I also think the often compared situation of mauna loa erupting more after 1840 eruption at kilauea should be taken as an inconvenient coincidence of when historical records began, the volcanoes are very separate after the source region and do not really influence each other at all apart from massive flank sliding quakes like 1868. The last time mauna loa had an activity pulse was before 1500 and kilaueas activity was pretty different then than it has been recently (extensive summit overflows) so I would highly doubt they influence each other that much and it is just a product of a short and probably very incomplete written observational history for kilauea prior to 1868 (see paper I linked earlier). Mauna loas 1840 to 1950 activity period was indeed caused by mauna loa getting more of the hotspot at depth (30-60 km deep) but that had nothing to do with the 1840 kilauea eruption that was within the upper 8 km of the crust 50 km away from and totally detached from mauna loa.

        Turtlebirdman long hawaii comment #43 or something like that… Well I made it a week I think thats a record :>

        Quite an exiting time we live in right now, to have both iceland and kilauea going through periods of heightened activity, and now it looks like the virunga volcanoes are trying to join in too. We wont be short of lava anytime soon… If only nyiragongo was better monitored like hawaii so we could see it in real time.

        • Kilauea and Mauna Loa seem to alternate in short periods of dominance over the hotspot but the exact way they do remains unclear, my theory is that it has to do with the east rift of Kilauea as it has a marked episodic character of activity. It is not the first time I mention this but I would say that when the ERZ is more active Kilauea takes more magma from a shared source or a souce located nearby to Mauna Loa’s and influencing it by reducing the supply to this volcano. This model agrees with the evolution of supply to the systems during the historic period and would predict that the supply to Kilauea will keep going at high levels or rise more while the supply to Mauna Loa keeps lowering until the current episode of ERZ activity ends. According to this model the intepretation of the 1840 events would be that the supply to Kilauea was already in decline from a peak around 1790, and continued after 1840 with Mauna Loa activity rising meanwhile.

          • I doubt that there is a direct connection between the two. They act from separate magma chambers. But nearby volcanoes do affect each other: see for instance the Holuhraun eruption inducing a silent period of two years in Grimsvotn. It probably acts through pressure. As one magma chamber drains, the stress field changes. Or it can be through the bottom of the crust, as in communicating vessels. It is too fast to be actual magma transfer, so it has to be an indirect effect.

          • HVO have done studies on stress fields between the two volcanoes and they are not strong enough to induce that sort of connection as an explaination for their behavior. Most likely it is simply where the majority of the magma is going up. Due to the shape of the underside of the island that means unless it goes up directly under mauna loa it will be deflected south to kilauea

          • This interaction would most likely be taking place at around 30 km depth, to where the conduits extend vertically, the conduit of Kilauea then extends laterally to the south, with Mauna Loa it is not well resolved.

          • That is the main conduit, at the center of the plume, but all the volcanoes receive magma from all around. 1924 deflation apparently indicated a source on the other side of kilauea to the east and slightly north, and 1959 got most of its magma from deep under the island north of kilauea, so the pahala source is not the only place kilauea is fed from. Mauna loa likely has a more restricted source area as its summit is overlying the thickest part of the island, which again will most likely channel magma down southeast towards kilauea and to a lesser extent loihi. This is actually exactly the sort of motion the magma seems to be taking when it is described that magma moves laterally under the crust from pahala to kilauea.

          • Considering that Hawai’i has probably moved a “whopping” 2 km to the NW in the past 20,000 years (aka considerably less than the rim-to-rim distance from the NW to the SW edge of both the Mauna Loa and Kilauea caldera craters), literally any combination is possible.

            The long-term .21 km3 / year average supply rate for Hawai’i over the past million years has probably not changed too much and near-term future growth (geologically near-term) will probably be on about that same scale.

            Both Mauna Loa and Kilauea are 100% active and both will erupt a lot in the future.

          • Dear BadWolf ..
            21km3 for Hawaii every year as supply ?!!??
            Thats flood basalt range
            And way too large number

            Hawaiis total magma supply for all volcanoes maybe 0,4km3 every year and 0,2km3 for Kilauea

            Had Kilauea and Mauna Loa had 21km3 supply every year
            They woud go totaly nuts
            And become Ontong Java Plateau

            The deep partial melting region 200 km under Hawaii generates many many km3 of magma yearly and a some ammounts of that gets feed to the shields

          • note that the 21 has a point in from of it meaning 0.21 km³/year which is the long term growth rate (or in other words supply) to the Big Island, most of it is taken by one volcano Kilauea or Mauna Loa depending on which is dominant at that certain time. During Kilauea periods it seems to take almost the full amount or even more at times.

          • Yup, while it is certainly possible that, in building up a 200,000 km3 pile of lava over the past million years, Hawaii’i’ has indeed had a few really rough years with 10’s of km3 or more in an individual year, an average of 21.0 km3/year over a million years is not a realistic output for a planet this size. That would have filled about 1/3 of the entire North Pacific or completely filled the Gulf of Mexico ~10 times or the Mediterranean ~5 times.

            0.21 km3/year is still quite a lot.

          • Badwolf its not anything to do with the relative motion of the island, its to do with the topography of the underside of tge crust beneath the island. The lava thickness under kilauea is about 10 km, while the thickness of the island under mauna loa is more like 18, and its probably a pretty cobsustent number between 16 and 20 km going up the chain to oahu where the modern configuration of the islands starts. Kilauea is above tge part of the island with the least mass so the bottom of the crust will be angled upwards to the southeast, and tge location of the plume head means all the magma is basically being channeled towards kilauea. Maybe occasionally the rising magma in the plume will rise into mauna loa directly and not move south to kilauea, that probably happened between 1840 and 1950. However the two volcanoes do not alternate at century intervals, the last period before 1840 that mauna loa was very active was before kilaueas caldera formed, probably 600 years ago, so most likely kilauea will keep doing its thing for the rest of our lives and then some. Mauna loa will indeed erupt in the next decades, by world standards it is still extremely active (hualalai or haleakala could also be considered very active volcanoes by world standards though) and it is still being fed magma, but like 1984 this will be a one off that takes decades to refill to again.

            Everything right now currently suggests kilauea will only continue to grow ever more dominant of the plume for the forseeable future, and that if any volcano is going to take it that volcano will be loihi not mauna loa. Mauna loa still erupts tholeiite but the transition from shield to post shield is long and not exactly linear, and likely mauna loa is entering this stage now while kilauea is at the start of its massive growth stage, where it will ultimately become a true giant probably even bigger than mauna loa if the length of the rift zones is any correlation to total final size.

          • Eh, for research and analysis I am focused on, I’m personally not all that fussed about which rift zone or caldera is next or will be most active over the short run.

            Caldera or rift zone areas are most “normal” but pretty much anywhere on either mountain is a possibility and has happened before.

            Overall supply rate is more interesting to me than where, specifically, the next eruption is located.

          • While the topic is open though, I have thought of a possible explsination to the reasons hawaiian volcanoes behave the way they do in their lifecycles. First is the current situation on the big island. Kilauea is the thinnest part of the island, the lava thickness northwest is thicker, probably around 17 km on average but kilauea is only 10. This means the crust flexes down less below kilauea which will direct nearly all the hotspot towards it. Mauna loa has not grown much in tge holocene, it is not really ‘shield building’ anymore despite its activity. This is probably because its feeder is not receiving much magma. The point im making comes into play when you consider that in its youth msuna loa would have been in the same situation as kilauea, a thin crust where the hotspot is diverted to it by the older thicker crust of hualalai and mauna kea. Thus leads to rapid growth and fast subsidence rate until eventually it falls to the same level as the other volcanoes and the hotspot diverts to the next volcano. Now that volcano (kilauea) will start rapidly growing, only rarely and incompletely challenged by its declining predecessor. Some day probably in around 200,000 years kilauea will be a volcanic behemoth that gives way to loihi in this manner. Of course the old volcanoes still receive magma and can erupt at low rates for over a million years after their shield stage and infrequently even later but the initial bulk growth stage is short lived and very voluminous, most of mauna loa probably formed within about 200,000 years ending maybe only 20000 years ago and kilauea might have only taken the hotspot for good 1500 years ago.

            Basically a new hawaiian volcano is thin crust so magma will flow towards it rather than to its older neighbors that have thinner crust, and that will drive vigorous and frequent activity, increasing its suze until it too sinks to the level of its neighbors and the next volcano in the series gets a boost while the older volcanoes erupt from more minor melting. This is suppirted by current seismic data about the pahala swarm. In hawaii today the plume center might actually still be closer to mauna loa, so in the future kilaueas already high activity could increase even further as it ends up on top of the hotspot. By the time it is at the end of its shield stage the current ground at halemaumau could be 8 km below its summit at that time, or even more.

        • Just wait until the African Superplume
          Really Gets through the East Africa
          Earths largest mantle plume
          It may have the capacity of a Deccan Traps sized event

        • Mauna Loa is around 300 000 to
          350 000 years old
          All of Mauna Loa thats above sealevel
          Formed in around 170 000 years I think

          • Mauna loa is closer to half a million years old, but most if its growth was in the last 200,000 years. Hualalai and mauna kea are about the same age and broardly overlap (hualalai is apparently slightly older), and both started growing about 900,000 years ago, and kohala about 1.2 million years ago. Kilauea is about 250,000 years old and loihi is most likely less than 50,000 years old. Kilauea now is about as old as mauna loa was when hualalai and mauna kea started their post shield stage.

            The next hawaiian volcano will very likely be east of loihi, and will probably form in the next 200,000 years. It has already got a name too, keikikea.

        • Had the African Superplume been oceanic we have have had an active Tamu Massif version today

          But that plume is not as strong as Ontong Java Event or Pangea Superplumes

        • Turtlebirdman I visted Kilauea and Mauna Loa my favorite volcanoes this christmas the coldest month
          Im supprised how warm Hawaii is in winter is on sealevel
          Despite its 2000 km north from equator and completely oceanic

          In Kailua Kona I got 34 C in shadow at sealevel at noon in coldest month of the year. I expected it to be mild 24 to 27 C

          But the Kona Nights on sealevel in december where acually quite chilly
          Global warming will make Hawaii uncomfortable as heck and places like India thats contiental will boil in a warmer worlds summers

          • Kona is probably hotter because its more arid, it rains a lot more on the east side of the island and its probably colder there. Its also cold above 1 km altitude there has been frost and below 0 C temperatures at HVO before, and obviously it snows on the taller mountains. In the ice age it probably snowed to maybe 500 m elevation, meaning all tge volcanoes would gave been snowed over and the highest peaks with glaciers.

          • Manu Kea is the only Hawaiian peak that has ever been ice capped.

            There is evidence on Manu Kea from as many as 3 or 4 separate ice sheets over the past 250,000 years extending down to as low as a 3200 m elevation.

            Manu Loa was either too short and/or too hot and erupting during the last ice age to have been ice capped.

            While it is possible that, over the the entire Pleistocene Epoch, that a snowflake or two may have drifted down as far as 500m elevation in Hawaii area, it is not likely that it stuck to the ground for very long anywhere but on the peak of Manu Kea.

          • Or any evidence of Mauna Loa being glaciated has been erased. Practically all the volcano has been resurfaced in the Holocene, the only exceptions being a few coastal areas.

          • Mauna loa almost certainly had glaciers, it was basically as big as it is now in the late pleistocene while this was happening.

            Basically about 80% of the southern half of the big island is covered by holocene lava, about 80% each for mauna loa and hualalai, 5-10% for mauna kea and over 99% for kilauea. The south side of kilauea is also not likely to survive the next series of summit overflows that will probably happen in the coming decades to centuries, especially if that activity comes from a vent further south than the caldera now as would be favored by long term trends.

        • Hawaii is 2000 km from equator
          Turtlebirdman

          During the glacial maxium peak
          30 000 years ago
          Maybe Hawaii at sealevel had same climate as Azores and Madeira today?
          Humid mild Subtropical instead of todays
          Tropical Hawaii?

          • Most of the big island isnt tropical, its too high up, only the low parts of tge islands on the east side are tropical the rest is either arid or anywhere ranging from temperate to sub arctic. As said before even on kilauea it has got to freezing before, and most of the rest of tge island is higher than that as well as far from the ocean. It is hot lower down even in winter as you have experienced personally but higher up it is probably rarely above 10 C in winter, and probably never gets above freezing on the high summits.

            The occurence of copious clouds over halemaumau in the morning right now is evident to the night being cold at that altitude, the air at the bottom of the crater is probably very hot but it rises into cold morning air and condenses and makes clouds like when you breath out on a cold day.

        • Turtlebirdman: I knows that, Big Island haves around 10 climate zones
          And frequently snows on Mauna Loa and Mauna Kea summits

          But sealevel is warm tropical
          How warm was Hawaiis sealevel during the glacial maxium?

          • Most, if not all, of the state of Hawai’i is technically not tropical at or near sea level. I’d call it subtropical, actually. Temperatures aren’t always that hot year-round. January to February typically see daytime highs in the mid-20s (C, *not* F!), though it can occasionally get in the upper 20s. Which is good, because it can be very humid, even in the winter months. It can also get surprisingly cool at night sometimes, esp. if you’re at the beach, to the point that a light jacket would be a good idea. Remember, this is based on my travels to Maui, where I go every year in January or February.

          • I have to add that the eastern part of the Big Island *is* indeed technically tropical in the coastal parts in places like Hilo. In fact, the eastern slopes of Kilauea has tropical rainforest (likely nowhere near extensive as it used to be before Captain Cook came along – humans are very, very bad news when it comes to such ecosystems). Hilo gets about 127 inches (3219 mm) of rain per year – this is more than enough for a tropical rainforest. Probably the only place within the 50 United States where one can find actual tropical rainforest!

          • Dunno, Puerto Rico has a fairly well touristed rain forest in the region near Roosevelt Roads.

            Though technically not a state, they enjoy the benefits of citizenship without the burden of statehood… They like playing both sides of the card.

            if I continue, I will wind up breaking the “be nice” rule.

          • Big island haves many climate zones: Artic Summits with almost permanent freeze
            A cold temperate interior
            A temperate lowver interior
            Tropical Semi Desert and Savannah In Kona and Kohala south sides

            Tropical rainforest climate in Hilo and Puna and Kau
            And temperate Woods higher up

          • Yes, there *are* indeed different climate zones for different altitudes in Hawai’i.

            As a matter of fact, I went up to the summit of Haleakala a couple of years ago as a part of a tour group. Of course, this meant getting to see the different ecosystems at different altitudes. There are even eucalyptus forests (certainly not native to Hawai’i – they probably got imported from Australia), I went into one of those, and it does indeed look like somebody put a piece of southern Australia and plunked it onto Haleakala’s slopes. This is about 3500-4500 feet ASL. You could even see that distinctive bluish haze coming from the those trees as well as that distinct smell of eucalyptus oil. Higher up, the trees become shorter and sparser. Then there’s the tundra terrain on top, where the only large plants are the famous silversword plants.

        • Alternative History 😉
          Had Hawaii been in latitude 65° South Pacific
          Almost the whole of each of Hawaii Islands would be Ice-capped.. glaciers would cover 85% of Big Island as Hawaii is rather tall above sea-level everywhere. A large Icecap woud cover most of Big Island. Only Hilo bay and Puna Lowlands would be ice-free and look like Iceland’s cold harsh rift zones.
          paradise would be no more. And glaciers spilling down to sea-level on many sides on Big Island. Hawaii would be very very cold indeed if it was in latitude 60° in South Pacific
          Latitude 60+ south in South pacific is even colder than Iceland’s beacuse of lack of Gulf Stream. Big Island woud be totaly icecapped
          Instead of a clear blue ocean…
          its green full of plankton and rich in Kelp
          Pengiuns and Elephant Seals crowds Kilaueas coasts and seabirds in their millions.
          Icebergs are frequently seen between the islands. The climate is mild oceanic polar with never very cold and never warm.
          Around – 10 c in winters and around + 8 C in summers and – 20 c at summits constantly
          Onshore its treeless with only moss and some grass and hawaiian icecap
          And there are no humans and no history
          Only explorers and whalers have visted that Hawaii in history and in 2018 only some volcanologists and biologists visits these remote cold Hawaiian islands

          If that was the case Turtlebirdman almost none would care about Hawaii down far south in Antartica Ocean. Only geologists do
          Unkown, mysterious, uninhabited. only visited by scientists once in a while.
          Cold and windy and rainy and miserable too. Only us volcano-fanatics would care about Hawaii if it was in latitude 65 south pacific. And the island would only have been discovered by brave explorers in 1730 S




  10. Discovery Channel has a new program: “Sinkholes: Swallowed Alive”

    Watched a couple of them. It is a full on PATHETIC program. The one featuring the Bayou Corne sinkhole appears that they didn’t even consult the research papers on the thing. 80% of the program talks about UK sinkholes…. just like the one about Florida sinkholes.. which they also seemed to gloss over. Lots of repeated footage and not very informative.

    On a ten point scale, I give it a “bleh”.

    • Btw, Florida sinkhole systems tend to roughly follow the traces of the transform faults left from the opening of the Gulf of Mexico where it has fractured the limestone basement rock.

      Stevens et al is a good reference for that. (Basement Control Structures of the GOM basin)

      And the only reason my interest has perked up on the matter, is a collection of about 6 quakes near here in the last couple of weeks. (The largest had the energy release of about 1750 hostess twinkies, but most were in the 200 twinkie range)

      Responsible fault? The Port St Joe fault. (Runs from there up to near Century Florida.)

      • I’ll put together a comment with details soon.


        The Twinkie scale is an arbitrary construct that I came up with due to people becoming quite excited over every little quake that occurred following the Eyjafjallajökull eruption. Reporters try to embellish the size of explosions with equivalent units of “Hiroshima bombs,” ostensibly to give the reader a familiar frame of reference, but sine no one really knows the full extent of Hiroshima, other than a city being destroyed and to push the myth that nuclear anything is ‘bad’, the tactic is not a useful reference and has no actual meaning other than that. So, it’s now just a hype tool to get more attention. My intention was to go the other route. Not all quakes are meaningful when it comes to Volcanoes. “Wet Quakes” (Carl’s term) and “Poppers” (my term) have an actual meaning about a volcanoes undergoing dynamics.

        How the Twinkie scale works. All earthquakes are a release of seismic energy of some sort. Generally, the intensity is given on a magnitude scale. The first problem is that there are several magnitude scales in use by geological organizations across the world. Some of these scales are based off of the maximum deflection of a seismo, others take the length of a quakes coda into effect. (Mglb). As a quick way to find the energy release, I use an tool such as this. The result is in Joules. For the conversion to Twinkies (something many people are actually familiar with) I use the post bankruptcy 135 Calorie Twinkies. 135 Calories is the “food energy” that you get from eating one of those sugar rush wonders. That’s equivalent to 135 kilocalories, or 630 kJ.

        Since it is my scale, I can denote it’s useful range. Anything above a Mega-Twinkie is defeating the purpose of the scale and probably indicates that there is something probably significant about the quake. Remember, Twinkie scale is meant to downplay the severity of a seismic event so that more rational thought and discussion can take place about it’s meaning. It doesn’t mean that it’s insignificant, just that there is probably NOT a calamitous event signaled by it. You can make Twinkie sized events in your back yard just by dropping an engine block onto the ground.

        Note: A “Wet Quake” is a quake that has a drawn out coda and seems indicative of some sort of fluid movement following the initial fracture.

        A “Popper” is a short duration Tornillo style waveform. Tornillos as seen at Galeras are screw shaped and last more than about 10 second or so. “Poppers” are not a scientifically recognized or used term. My interpretation of them are they are the creaking and popping of a dike intruding into rock. They also have a small “wet” signature in the coda.

        • The problem with the twinkie scale is that the twinkie is not a Universal Constant, but Bic Macs are everywhere.
          That is why I asked for the conversion ratio from twinkies (imperial) to big macs (metric). 🙂

          • Hang on. That makes 10 big macs approximately equal to mag1 according to the above graph. Now that’s a teeny amount of energy I’ve known hen parties manage vastly more just in alcohol consumption.

            Is it right that this little energy is enough to stop fracking in the UK?

            Unbelieveabubble….

          • Yes, that is correct. I make it about 5 mars bars for one M1 quake. Tells you everything about mars bars.

          • … and according to the local “news” Geologists are in the area to study the ongoing “sort of a swarm” that we have in progress.

            I was thinking about heading up to Century to drop a couple of 3 axis accelerometers and hang out for about 2 hours collecting some data myself. You know, time sync them and bring them back for audio processing, Carl style 😀

  11. Nyiragongo keeps having a huge thermal emssion from space: lots of yellow and red squares in the satelite instrument.
    This is the lava lake and all overflows into caldera floor.
    Pressure is high now in Nyiragongos magma chamber

    • Its probably not going to do any big flank drain out yet though, the lake is quite low. It will probably keep this up for a while filling in its crster up to at least the inner ledge and maybe the 1977 ledge, or even higher, but it will take a bit to get gravitational collapse. Its probably a similar situation to puu oo in 2011, with a big lava lake filling the crater and when it rose high enough to overflow the crater it broke out the side of the cone and drained out mostly in the first few hours though continued at high rate for a few days. The key point being that the lake will likely have to either get a lot wider or much higher to collapse.

      Both the virunga volcanoes will probably be doing some interesting things in the next decade though with their high lava stands and prolific magma supply (probably 3rd in the world behind hawaii and iceland), and this area in general is also a serious contendor for a future big flood basalt and is probably even now capable of holuhraun or fissure 8 sized eruptions, which is not a great situation to have a rapidly growing city of at least 2 million next to… Goma has seen the relatively very small 2002 eruption but nothing else (it was much smaller in 1977) and a way bigger area is covered by lava from a few hundred years ago, and nyiragongo might have only started erupting its current ultra fluid lava in the last 500 years and that is too short to be subject to geological time. If there is a study on what sort of rocks nyiragongo is made of that would help but im willing to bet most of it is not nephelinite.

      • Nyiragongo is likley very Young
        Its a small and steep stratovolcano
        Very very youthful looking in the hot tropical climate and constant rains.
        Nyiramuragiras 550km3 shield is similarly youthful and crisp looking in this wet rainy climate. The two volcanoes likley started forming in late pleistocene maybe much younger
        Infact the whole Nyiragongo – Nyiramuragira is Area likley less than 25 000 years old
        ( but the older Virunga volcanoes are older )
        2 million persons living near two volcanoes are indeed problematic.
        There are lots of monogentic vents and 10 s of cinder cones in Goma arera alone.
        A full blown cone building flank eruption at (0,1 to 0,6 km3 ) range is a full possibilty for soure in middle of Goma today. An invasion of Superfluid Nephelinite lava will certainly happen again.
        Goma is growing rapidly and the volcanic damage becomes larger through that.
        Nyiragongo flank eruptions are rarely very large but the eruptive rates are enormous combined with super – fluid Nephelinite and steep slopes. And densely populated arera
        2002 had eruptive rates of 6000 cubic meters a second the first hour! And the lava rapidly flooded Goma and rushed into the Kivu lake
        It all was over just in a few hours.

        The current lava lake in Nyiragongo is growing higher and higher and overflowing the caldera floor building the caldera floor higher and higher perching itself like Puu Oo in 2011 and Erta Ale 2017. As the lava lake grows higher the pressure in Nyiragongos conduit increases the chance for intrusion and flank eruption.

        Indeed Nyiragongo haves the wrong shape for its madely runny superalkaline ultrabasic Nephelinite lavas. Nyiragongo haves always been alkaline but earlier lavas where likley sillica rich viscous alkaline rocks like Trachytes, Phonolites and Tephrites.

        Only recently Nyiragongo haves changed to its ultrafluid and ultrabasic superalkaline Nephelinites. Nyiragongo is 34% sillica today and around 1260 c to 1300 C
        2002 was 1370 C at upper vents, the hottest lava ever known so far. ( Hawaii during Iki was almost as hot )
        The 2002 lavas from Nyiragongo when lava lake was reformed was totaly free of any crystals just glass bubbles in black glass matrix, very fresh from the source

        • This large mantle plume and continetal rift
          Makes this arera a serious candidate for future moderatly sized basalt floods ( a while in the future )
          Nyiramuragira already does very fast and large fissure eruptions ( 2011 was quite big ) there are also huge scoria cones and monogentic tuff cones in Virunga, its another sign of gas rich large lava eruptions.
          It may not have Icelands or Hawaiis maxium capabilities yet
          But thats a serious possibilty when time passes. ( wait 700 000 years )

          Nyiramuragira haves a very smooth shape and mostly consists of pahoehoe lavas of basanite composition
          Cannot see any older Aa flows of fast fissure eruption on it.

          Only recently ( last 1000 years ) it seems to have producing fast fissure eruptions with Open lava channels and Aa flows.
          Today its doing lava lake activity again.
          Nyiramuragira is high potassium basanite and product of sligthly higher partial melting than Nyiragongos Nephelinites.
          Still Nothing in the Albertine Rift is anything close of Subalkaline.
          This arera is the most alkaline sillicate lavas on Earth combined with Mount Erebus and other African volcanoes.

      • Supprising superalkaline magmas like
        Melinite -Nephelinites are made in souch wast ammounts that permanent lava lake is possible in Nyiragongo

        Souch extremely alkaline magmas are products of very very very low degrees of partial melting in the mantle
        Nephelinites are typicaly never ever produced in any large ammounts.
        The Ohau seafloor flows are extremely supprising ( nephelinite flood lavas )

        Most flood lavas are very thoelitic basalt in composition and product of very very high ammounts of partial melting.

        When I thinks of Nephelinites
        I think of small monogentic Fields of extremely alkaline cinder cones and small lava fields

      • The oldest lavas from Nyiragongo are similar in composition to current ones, in fact they were more SiO2 poor about 36-37% the reason why the cone is so steep is that most of these even though very fluid were erupted explosively, there are even large blocks a few meters in diameter exposed in the caldera walls. The cone was later draped in thin lava lake overflows meaning that the lake sometimes may fill the caldera all the way up to the rim.

        • Sounds like it is more of a scoria cone that is the size of a stratovolcano, rather than an actual stratovolcano. Would explain why it behaves the way it does, like a gigantic version of pu’u o’o.

          • Sounds as if it kicked off as something like a kimberlite pipe, then just sort of carried on growing

      • Still Nyiragongo and Nyiramuragiras relativly small sizes.. fits well with being superalkaline and low degrees of partial melting deep down.

        Activity in Albertine rift is on an increase
        The local mantle plume there have uplifted a 600 km wide round arera , 1,6 km above sealevel
        The plume will and is rapidly decompressing.

        In the future activity will increase and partial melting too. The arera will likley change to more subalkaline magmas in the future.

        Thoelite basalts will likley emerge in that arera in the future and take over the current super sillicaundersaturated alkaline rocks

        • The virunga volcanoes are also the only active volcanoes on that stretch of the rift, the huge size and great depth of the lakes in those areas is a test to the length of time this area has rifted with no volcanism, many millions of years. Then entirely within the last half million years a set of stratovolcanoes appeared, and now two very active effusive volcanoes are growing rapidly at a rate orders of magnitude faster than the older volcanoes. Nephelinite is as you say an alkaline rock and those are the product of the early stage of a plume surfacing, the erupted volume of the two volcanoes might be as much as 700 km3 in the holocene, which is about 0.07 km3 per year, or 7 km3 per century, a rate about half that of kilauea but this is only in its early stages before the plume really opens the floodgates of hell. This is the perfect storm for a flood basalt, and the size of the uplift indicates this will be far from small…

          According to HVO loihi is only a few tens of thousands of years old, and it now erupts tholeiite as opposed to alkali basalt, virunga isnt hawaii but going on these timescales and the scale if this system, tholeiite will probably erupt within the next few thousand years at one or both of nyiragongo or nyamuragira, maybe even the next few hundred.

          • How Big is Hawaiis uplift?
            Hawaiis plume swell on the litosphere
            I learned its around 1100km wide?
            ( Hawaii and Iceland are the biggest oceanic plumes )
            I knows Hawaiis plume swell is very big.
            But being oceanic it wont do flood basalt armageddon so easly as continetal versions of it

            The Congo continetal plume swell is around 700 km wide

            Then you haves the African Superplume that hides under the Victoria and Tanazia and Kenya cratons ( the biggest continetal plume )

          • Indeed scary lavalicious stuff is on the horizon in Africas Rifts
            These are one of the bigegst mantle plumes on Earth
            specialy African Superplume thats the largest plume for now

          • The African Superplume haves an uplift of around 2300 km wide
            Its a monster.

            Its hidden beanth Africas hardest and thickest parts, under the ancient cratons and haves trouble with that
            Not even ancient Pangea Suerplumes penerated a craton
            only the weak seams between them

          • There is that Local Plume in Nyiragongo Albertine rift

            Then we haves the African Superplume
            And there is the African Superplume to the east of Congo
            African Superplume is a monster! that plume head is under most of North East Africa.. and dealing with a very thick old 280 – 330 km thick litosphere and 50 km thick crust on top of that: The superplumes focus is in Kenya, Tanazania, Congo.
            All geochemical data and gas analysis and radioactive data and mantle tomography by seismic waves.. points to a single Mantle Plume under East Africa.
            The African Suerplume haves huge trouble witht the old cratons and magmas trying to find a way through the younger eroded orogenic seams between them

            This plume is much much larger than Hawaii but its also dealing with one of earths coldest and hardest pieces of litopshere
            Some geologists think Nyiragongo is feeding from the western edge of African Superplume head where it reaches surface Between very ancient Victoria and Congo Cratons.

            But your and my theory is likley more correct
            Nyiragongo is another separate plume in the Albertine Rift
            With African Superplume being more East.
            here is a good video about the African Superplume:
            https://www.youtube.com/watch?v=3jpbArY2L78

            Still Hawaii remains the strongest oceanic plume on the planet

          • Africa is up for major flood basalt hellageddon IF the African Superplume finds a way through the surface to really decompress in the uppermost mantle. In the future an event like North Atlantic Igenous Province in Africa is not an impossibility.
            In Africa the conditions are ripe for magmageddon

  12. Lurker here. Apologies if this has already been mentioned – an interesting interview with volcanologist Clive Oppenheimer on the BBC Radio 4 The Life Scientific programme and podcast, interview by Prof Jim Al-Khalili, which went out last December but I’ve only just found it on the iPlayer

    • Oppenheimer is good. He’s quite knowledgeable and candid, very pragmatic

  13. Is there an eruption starting in northern Iceland? The blue tremor frequency is excited, and there’s an ongoing swarm at varied depths at the same general area.

      • It is within the Krafla Fissure swarm. But, currently no cigarr… 🙂

        • Oh right, I thought the swarm was a bit further east than it is. Is it really likely to have an effect on the system with it being right at the end of it?

          • Tightly to the east is Fremrinamar, and close to the west is Theistareykir. It can have an effect but that would take some serious shaking.
            As a reference, Theistareykir blasted off an M7 without erupting.

  14. well things escalated rather quickly at Tjörnes fracture zone. 3.9, 4.3, 3.0 back to back?

    some of it is really shallow

  15. The Kópasker swarm has intensified with a maximum earthquake set by duty officer at IMO to M4.2.
    The solution is not final since there is simultaneous earthquake at 3.9 at shallower depth on the same location that should be homologated into the main shock.

    In other words, a sinistral faultplane opened up from roughly 5km up towards the surface indicating sprungur formation. The best fit solution is an M4.5 earthquake. As such it is sizeable, but not a big one on the local scale.

    M5s are not uncommon in the area, and the largest recorded earthquake is an M7.2 east of the current fault that is active.
    The earthquake happened at the junction between Krafla Fissure Swarm and a fracture zone leading over to the Theistareykjarbunga Fissure Swarm.

    Currently there is nothing pointing towards an eruption being in the making, but this is Iceland, and the earthquake happened on a known active fissure swarm, so things can change at a later stage.

    The effect on Theistarerykjarbunga was roughly a 3 minute long low frequency reverberation, at Krafla the reverberation was 2.5 minutes long. This reverberation is caused by ecoing tremor in the respective magma bodies, which is normal after a sizeable earthquake.

    There is a minor risk for a secondary larger earthquake happening at this site, or on adjacent sectors of the above mentioned faults.

    Currently there is a raised low frequency level at Krafla, but nothing else seems to indicate movement of magma, so it is probably just local excitation.

    I hope this cleared things up. If needed I will update this.

    • Just as a quick pointer of how much LF interference this earthquake caused at Krafla.
      On the picture one can see that the LF tremor (red) is up 2000 units above normal.

      • Isn’t Theistareykjarbunga that humongous critter sitting at the landfall end of the Tjörnes fracture zone? I think you have described it in the past as a “brute.”

        • From Wikipedia:

          “There have been three dated eruptions, all VEI 0: the most recent eruption was around 900 BCE and the previous eruption was in 6800 BC. Around 9500 BCE, an eruption produced approximately 18 billion cubic metres of basaltic lava.”

          • The volume of the shield is 35km3, plus the 18km3 of the initial lava flood. All of this came out of the 9500BC eruption.

          • I am guessing that Theistareykjarbunga owes its flattened shape, at least in part, due to the fact that the 9500BC eruption would have probably been mostly a muddy, floody, sub-glacial mess, at least at the start of the eruption.

            That much lava that quickly would have left a much less icy landscape in that part of the island after it was done.

        • Theistareykjarbunga… I think my mouth would go on strike if I tried to pronounce that.

      • Humongous as in a giant flat pancake of a shield volcano.

        • Yes, humongous as in having had Icelands largest eruption in the holocene. About as brutal as they come without being renamed Godzilla.

      • Thank you for the explanation. I had thought the higher frequency was reminiscent of some eruption examples, but admittedly know nothing of how to read them. I wonder what it is like at the actual swarm site. It looks to be on the coast or in shallow water. Would one feel constant shaking at the site?

        • If you have your butt on solid rick you can feel the earthquakes above M2 if they are close. So, you would feel discrete shocks or rumblings, but not a constant tremor at all.

    • Carl I images the Theistareykjarbunga shield episode
      To have been very very long lived lava lake feed pahoehoe tube eruption. I imagines very much an Artic Version of Erta Ale
      Is this correct

    • Theistareykjarbunga Had a large lava lake when it was active feeding lava tubes too
      That likley circulated and bubbled for decades when it was really going

  16. We also had some tremor on the Big Island. Shows on many seismographs from 19:48 UTC 3/27/2019 till around 20:15 utc. This is stronger than the last one I think. There are two deep quakes south of Pahala that look like they might be associated with the tremor. They are in the same general area as the last tremor we saw.

    2019-03-27 20:01:02 2.1 24.9
    2019-03-27 19:54:34 2.6 26.7

    • Added a new quake and some more (but less intense) tremor. In the same area as the others.

      2019-03-27 23:51:06 2.1 24.7

  17. This is correct right:
    Carl I images the Theistareykjarbunga shield episode
    To have been very very long lived lava lake feed pahoehoe tube eruption. I imagines very much an Artic Version of Erta Ale Right?

    After the initial 18km3 flood basalt
    Theistareykjarbunga Became a slow lava lake pahoehoe tube eruption
    Only pahoehoe makes up Theistareykjarbungas lava shield

    • Personally, I’d like to see an accurate breakdown of the name from an actual Scandinavian.

      Gurgle Translate yields something like smoking bulge.

      • They used to be more practical in naming stuff back in “ye olden days”.

        Something innocuous like “Smoking Bulge” was probably a perfectly appropriate name at the time as it would not have been very interesting to the locals compared to Krafla just a few miles to the south. Krafla includes the crater Víti, one of two well-known craters by this name in Iceland (the other is in Askja).

        The Icelandic word “víti” means “hell”.

        Long Mountain and White Mountain are another couple of very practical names from ye olden Hawaiian days.

  18. Thats a vulcanian explosion… thick sillicous stiff magma builds a plug or lava dome and gas rich pressure builds under and blows it apart.
    This behaviour haves been the typical of Popocatepetl for many decades now.
    Popocatepetl constantly forms flat pancake lava domes and destroys them.
    The volcano haves a completely open conduit and constant magma inflow for now.
    If magma supply increases we can get either andesite flows spiling down Popocatepetl flanks or asubplinian eruptions if the gas is enough.

    Most likley it will do as its doing… making lava domes and destroying them with vulcanian eruptions
    Popocatepetl is incredibely dangerous upclose and I dont understand why persons even climbs it
    Here is a darwin award style video from a person that climbed inside

    • Popocatepetl summit climb
      NEVER attempt this! its crazy and this video was taken a while ago
      They likley climbed up just after a large lava dome destroying vulcanian eruption, knowing the voclano had let off some pressure.
      One can hear the intense roar from the fumaroles and at night the rubble in the crater woud likley glow in spots.
      This is the kind of grey explosive volcano that should not be climbed.
      had a vucanian eruption happened under the climb there.. they woud have no chance at all of escape. These kinds of viscous sillica rich subduction zone volcanoes are not friendly when gas rich

      • During Popo’s long (50 years and up) repose periods it’s been climbed by some Quite Famous people. Including Aleister Crowley and Che Guevara. And by a bunch of Cortes’ Conquistadores, who were after sulfur to replenish their stocks of gunpowder

  19. Scientists want to send a probe to study Io, Jupiter’s volcanic moon:

    https://www.space.com/io-volcano-observer-jupiter-moon-mission-proposal.html

    This should be very interesting, especially if the probe includes onboard cameras.

    Undoubtedly, the extremely dangerous radiation this close to Jupiter will make things very challenging. That kind of probe would require very heavy shielding and also require elliptical orbits not unlike what’s being done with the Juno probe.

  20. Just found one more volcano that is missing it’s top 2/3 and is very remote.

    Anahatan

    • This place looks crazy…… it could be straight out of a James Bond or Austin Powers movie as the villian’s secret island lab and lair.

  21. Taal apparently shows signs of awakening: The alert level has been raised from 0 to 1 due to a seismic swarm which started a week ago that showed around 50 events so far. Further the GPS shows light inflation, the temperature of the crater lake increased from 30.7 to 31.7 degree and the water level dropped by appeox. half a meter. Also Co2 emissions ramped up. Seems like a magmatic pulse?!

    • Uhh oh…

      Keep your eyes open for a fish die-off. Taal has a LOT of Tillapia aqua-farming operations.

      Per many tour guides… the island in the middle of the Lake is the Worlds Smallest Volcano. The problem is… THE LAKE is THE VOLCANO.

    • Latest early look temperature anomaly data based on GFS analysis is consistent with El Nino developing.

      The anomaly base years 1994-2013 in that chart.

      • Still the candaian winter high pressure still seems to be happy around Hudson Bay

        • The plot comes from moyhu’s blog. I don’t know why he used this base, but there is a case that now that temperatures are changing so fast, you should use the most recent base, while avoiding the exceptional en nino years around 2015 which would bias you. The plot in itself does not really show that an el nino is coming, but there are other indications that there is a weak el nino in progress. Whether it will become any stronger is speculation at the moment.

          • Also to clarify, I meant that the temp chart is consistent with the development of El Nino as it has progressed up to now – I didn’t mean to imply that it predicted anything about further development.

            And I also know the monthly data is quite noisy!

  22. I have a question that I may have asked before but I’m not sure. Is there a chance Mauna Kea will erupt again in the future?

    • Yes it will but it is very infrequent, it last erupted about 4000 years ago but longer gaps between eruptions have happened so it likely wont erupt at all any time soon. Its eruptions probably go from the mantle to eruption very fast though so we probably wont know until less than a week before it happens.

      • And it won’t be at the summit. There are many scoria cones a bit above the level of the saddle road, and a new eruption would likely add another such cone.

        • Eruptions seem to be clustered with many over a short period and then lobg dormancy. There are something lime at least 6 holocene cones on mauna kea but only 2 periods of known activity, at the start of the holocene and about 4500 years ago. Hualalai and haleakala also seem to work this way, hualalai erupted around 1000 AD and then again erupted aboht 6 times between 1780 and 1801. Haleakala last erupted in about 1650 but it erupted a lot more in the 700 years before that probably with multiple eruptions per century and some were pretty big, and so might not erupt quite so soon, maybe not in this century or beyond.
          This is a different mechanism to kilauea which is fed out of a much larger melt source, the hotspot center, where the rock is likely very nearly molten anyway and easily decompresses in huge volumes. Mauna loa is somewhere in between, not over the plume source but close enough that sometimes the plume still goes through it and where the general level of melting still generates tholeiite over alkali basalt.

          • Yup Hawaii leaves all other volcanoes in the dust when it comes to historical output and size.

            Only Iceland, Africa and Galapagos are the other plentiful erupters: But still far below Hawaii in supply and eruptive output in long terms

            But I wonder what kind of volcano will form when the African Superplume ( the largest mantle plume for now ) really finns a way through these cratons ( seams between them )
            The focus of the African Superplume is under Tanazia craton.
            This mantle plume strecth all way from Malawi to Somalia
            Imagine when it breaks through

          • It can’t be known for sure wether the recent flows of Hualalai formed in 1 or 6 eruptions, most likely it was 1 or 2 if you ask me. Hualalai is currently in a younger stage of life than Mauna Kea, though it has had 1 or more trachyte eruptions around 100 ky ago its more recent lavas are slightly alkalic or slightly tholeeitic meaning it is sort of in between, in a late shield or transitional stage which shows up in every older volcano that went postshield before it did it. Mauna Kea already had this phase of activity lasting from 300 to 70 ky ago, the Hamakua volcanics. The lavas during the late shield are more SiO2 poor than lavas of Kilauea or Mauna Loa, when a volcano enters post-shield it usually produces more evolved lavas ranging from alkali basalts to trachytes. Mauna Kea has progressed towards more silicic magmas starting with trachybasalts and more recently erupting trachyandesites, judging from other volcanoes it will probably erupt felsic lavas in the future. But each hawaiian volcano does it its way, actually only about half of the now extinct volcanoes had a postshield, Haleakala has spent about 1 million years erupting mostly alkali basalts, there are even flows low in the rifts that show pahoehoe lavas, West Maui instead went directly for the felsic end (trachytes)

        • Any future eruptions on Mauna Kea, especially at the summit region, would be bad news for astronomers. Mauna Kea is home to some of the largest ground-based telescopes in the world. There’s at least a dozen or so such telescope sitting on top of that volcano. Fortunately, such postshield eruptions on MK aren’t very frequent, and may likely not occur over the next several centuries or millenia.

      • Many most recent flows on Mauna Keas flanks are very massive and lobate and high edges in Google Earth
        These are large blocky Aa flows of Trachyte and Tephrite and maybe even Phonolite
        They are the very alkaline versions of andesite and dacite and ryholites depending on Sio2 content. Hualalai have produced even thicker flows a coulee and dome ( very viscous gas poor flows )
        Mauna Keas summit cones are alkaline basalts
        And most of Hualalai recent activity are sillica poor alkaline basalts.
        But Hawaiis fast magma supply and high ammounts of partial melting means
        99% of all that comes up during shield building stage is Thoelite Basalts

        • Hualalai used to be covered in even more trachyte, 100 meters thick flows have been found in drilling. Mauna kea is actually slightly younger than hualalai so it might still have a short lived stage of extensive alkali basalt flows covering over most of it before it goes to sleep. Some of its holocene flows have been very big, comparable to eruptions on mauna loa in scale. Kohala and mauna kea are relatively close to each other so maybe this is why kohala died without too much of a post shield stage even though it was once a huge volcano.
          While this is all speculative it does bring a new element of risk for long term plans in the north of the island. The old risk assessment map, with zones 1-9, would need to change. That map also needs to be changed right now though to account for changes in topography associated with puu oo. Eruptions north of puu oo actually will flow all the way north now and not just east like before, meaning more of kilauea should be in hazard zone 2 than before. It is not likely that a big eruption will occur at puu oos location anytime soon though so this might be more aesthetic at the moment.

          • Subalkalinity and alkalinty is fun too in Hawaii

            Over the hotspot ( Central and
            East Big Island ) very high degrees of partial melting and its hot Thoelite Basalts with similar compositions as the latest lunar mares
            And sometimes Picrite Basalts dragged up from the depths.
            These main shield stage lavas may have viscoities as low as 20 pas making them the most fluid among basalt.
            98% of a hawaiian shield volcanos mass are thoelite basalts rapid shield building phase.
            The plume partial melting pool under south Big Island is defentivly hot enough to melt all of the mantle pedriotite and form Komatite
            Kilauea Iki dragged up some very hot stuff.
            Hawaiian thoelites are known for their fluidity and high temperatures
            Eruptions are constant to near constant.

            West Big Island and Maui its farther away from plume focus
            And lower ammounts of partial melting. Kohala, Haleakala, Hualalai is alkaline basalts and trachytes depending on sio2
            Some lavas are very sillica poor and alkaline there. The 1800 s pahoehoes where pitch black alkaline basalt
            This happens when the moving pacific plate carries the Islands away from hotspot
            Alkaline postshield stage
            shield alkalic stage eruptions usually consist of large volumes of cooler gas-rich mantle xenolith rich alkaline lavas.
            Some old Hualalai flows are completely filled with green mantle pedriotite xenoliths. Rapid accent from great depths
            Eruptions happens every 1000 years to 1000 s or some 100 s of years apart

            The Post Erosional Rejuvenation
            Ohau and Maui is the last volcanism before an Hawaii island dies competely
            This is the very most alkaline magmas
            That acend from huge depths
            Partial melting is now very very low and of small degrees and that generates extremely alkaline rocks like Basanites, Phonolites, Tephrites, Nephelinites depending on Sio2 content
            Nephelinites / Basanites seems to be the base melt thats produced and may evolve on the way up
            Eruptive constructs are monogentic and only erupt once in Rejuvenation phase.
            The volumes per eruption can be sizable but eruptions are few and many tens of thousands of years happens between them

          • Haleakala is still in its post shield stage like hualalai and mauna kea, it has never had a really long dormancy, it just hasnt erupted enough to offset erosion after about half a million years ago. True rejuvenation eruptions are small eruptions that happen when the parent volcano is otherwise extinct with no shallow magma system at all, only the deep roots of the volcano, likely all of the islands are still within capability of erupting this way even kauai or ni’ihau. The prevalence of large volumes of evolved magma on post shield volcanoes, as well as the still large size of a lot of the eruptions, likely means these volcanoes still have a magma storage system where magma can evolve. The supply to hualalai is small compared to kilauea, but by world standards it receives magma at a rate that is much higher than a lot of large volcanoes that have no doubt got large magma systems, its last eruption was only 220 years ago, and it was a big one, likely at least 0.5 km3 or more in total. This to me, along with known cases of eruptions as big as 3 km3 of felsic magma, is a pretty good indication of large volume magma storage in hawaii inside post shield volcanoes, it is probably just stored at depth beyond where it can become a caldera.

            One other thing to consider regarding that, haleakala apparently has a significant portion of its post shield volume made of andesite, enough to underly almost all of its current subaerial part. This is not trachyte or phonolite, or any alkalic rock, just normal andesite, which is evolved out of tholeiite basalt…
            What this means is not really well known, but it evidently gives a much wider spectrum of what hawaiian volcanoes can do. With fissure 17 last year and basaltic andesite erupted at the kamakaia hills in the early 19th century though it is a little less surprising.

          • Yup of course Haleakala is a Classic postshield volcano
            I wrote wrong misstake

            Adims may Edit commentary above

          • Of course Haleakala is a postshield hawaiian volcano and the most famous example of it
            Even Haleakala is larger than all other subduction cones combined
            Woud not supprise if Haleakala, and Mauna Kea evolve a small ryholite batch later in its life from a stale andesite
            Or its alkaline equalent
            IF granite is ever found in the older eroded interior of older hawaiian Islands its signs of old small highly evolved chambers at the end of postshield stage.
            Even Dacite was found in Kilaueas ERZ zone from old stale evolved basalt

          • Something else to consider is the possibility of much bigger eruptions from older hawaiian volcanoes than generally inferred. It is only in the last year with the long considered far off formation of a deep summit caldera on kilauea that it is now generally accepted it can erupt violently, but even the biggest explosive eruptions on kilauea probably cant get above a borderline VEI 5, before magma either intrudes or erupts elsewhere or widens the vent to where the lava flows out effusively. The biggest eruptions on kilauea will always be dominantly effusive unless they occur down in the LERZ right on the shore at cape kumukahi and that isnt a common location.
            On post shield volcanoes I would expect possible mid VEI 5 eruptions or even up to almost VEI 6 if the old evolved stuff gets going. The puu waawaa trachyte eruption was mostly effusive but the initial eruption was mid size VEI 5, 3 km3 of tephra, then probably over 1 km3 of lava was erupted on top of that, and the same pocket erupted twice with another effusive eruption 50,000 years later. The prevailing idea with the lifecycles of hawaiian volcanoes is that after they go into post shield stage their magma systems solidify and eruptions are deep sourced and radial but none of the volcanoes actually show this on the big island, eruptions on hualalai are very rift oriented and for tge most part follow the same patterns as eruptions on kilausa or mauna loa, and same for haleakala that ended its shield stage before most of the big island was even a thing at all. Mauna kea is radial and erupts infrequently, but it never seems to have actually had rifts in the first place anyway and it is in the center of the island where there is more crust to go through. The only thing that really changes is the lava composition, becoming more alkaline, but that is actually quite common for basalt erupted outside of mid ocean ridges. Effectively the post shield stage is where the hyperactive shield stage volcanoes become ‘normal’ volcanoes again.
            Hualalai is low supply compared to kilauea, but so is almost every volcano, and looking at the averages for subduction volcanoes it actually isnt so low at all, it is far from a small dying volcano at any rate.

      • The glacial permafrost lake at Mauna Keas summit is rapidly melting and becomming less alpine: Before the industrial revolution co2 explosion Mauna Keas alpine lake likley froze really deep in Winters

      • Thoelite basalts can evolve into andesite, dacite, ryholite ( like fissure 8 s hot andesite ) and so on

        Alkaline Basalts evolve into the alkaline path
        Tracytes, trachyandesites trachydacites
        and very alkaline ryholites
        and Phonolites

        Very alkaline rocks like Nephelinites evolve into Tephrites tephriphonolites example

        If Haleakala haves subalkaline normal andesite its a sign its deep basalt supply is subalkaline thoelitic And makes sense… since it haves a rather large supply compared to other subduction zone volcanoes in the world

      • Turtlebirdman
        African Superplume is currently the largest mantle plume: Do you think its capable of a Deccan Traps sized event ?
        Something will happen when Africa rifts a bit more and the plume head decompresses enormously this plume head is under most of East Africa by geochemical and seismic analysis

    • Plenty of stuff to feed apocalypse fantasies fancied by some of our VC posters!

      • Obviously a controversial story with only one paper out so far. But a huge amount of data to to be published in near time. Let us wait and see when more is published before turning it down.

Comments are closed.