Volcano World Cup 2018: Quarter Finals

So we’ve now reached the quarter final stage of the Volcano World Cup and this is where the competition starts to tighten up when serious volcanic nations come up against each other. Do the usual, vote for whoever you want to progress to the semi finals.

 

Russia vs Peru

RUSSIA

Chirinkotan Volcano. SOURCE: www.openarium.ru

I thought I’d make use of the Kurile Islands and pick Chirinkotan to go up for Russia. This small island consists of an above the water summit of a stratovolcano which has a small caldera breached to the southwest. Historical eruptions date back to the 1800s but the most recent eruptive period occurred during 2016-17. Lava flows were witnessed in the 1880s.

PERU

Huaynaputina Volcano. SOURCE: radioamericana.com.pe

For Peru I choose Huaynaputina to go up against Chirinkotan of Russia. Huaynaputina has only had one historical eruption but was a mighty VEI 6 eruption which occurred in 1600 resulting in the construction of three overlapping ash cones within the depression breached to the east and pyroclastic flows which travelled 13 km east and southeast. Lahars reached the Pacific.

 

Costa Rica vs Colombia

COSTA RICA

The main crater of Volcan Irazu. SOURCE: www.pointswithacrew.com

I choose Irazu to represent Costa Rica going up against Colombia. Irazu is a large 3432m high stratovolcano which is located east of the capital San Jose. Frequent eruptions have occurred since the 1700s but the most recent eruption came in 1994 when a phreatic eruption occurred on the upper northwest flank. A significant eruption during 1963-65 caused a lot of ashfall which disrupted the surrounding areas.

COLOMBIA

Purace Volcano. SOURCE: www.parquesnacionales.gov.co

Purace will represent Colombia to go up against Costa Rica. This volcano has had numerous eruptions dating from 1816 going right up to 1977 with the largest eruptions occurring in 1849, 1869, and 1885.

 

Spain vs Iceland

SPAIN

The 2011-12 underwater vent eruption of El Hierro. SOURCE: sge.org

I will pick El Hierro in the Canary Islands to go up against Iceland. This island contains numerous cones and a massive collapse scarp which is present to the northwest of the island caused by the gravitational collapse of the El Golfo shield volcano. A recent eruption occurred during 2011-12 from a submarine vent to the south of the island.

ICELAND

Surtsey, a volcanic island born out of the sea in 1963. SOURCE: dosecc.com

For Iceland I choose Surtsey to go up against El Hierro. This small volcanic island emerged from the sea in 1963 producing phreatomagmatic explosions before eventually building up high enough to prevent the sea from washing away the loose materials, enabling the eruption to become lava fountains producing lava flows which formed a hard shell on the new island preventing erosion. The eruption ended in 1967. Surtsey is part of the Vestmannaeyjar submarine volcanic system.

 

Mexico vs Japan

MEXICO

The huge crater of El Chichon. SOURCE: www.mexicodesconocido.com.mx

I choose El Chichon to represent Mexico for this one. The only historical eruption was in 1982 when a huge VEI 5 eruption occurred blowing apart the lava dome that once made up the summit area of the volcano, forming a 1 km wide crater. Pyroclastic flows occurred devastating the area within a 8 km radius plus destroying the village of Francisco Leon in the process. An acidic lake now occupies the crater floor.

JAPAN

Unzen Volcano. SOURCE: www.photovolcanica.com

For Japan I choose Unzen, that volcano which claimed the lives of Maurice and Katia Krafft during a pyroclastic flow. It is a complex volcano located in southern Japan which had much of it’s historical activity on Fugen-dake but also on the Mayu-yama lava dome complex. The most recent eruptive period came in 1990-95 (and later 1996) when a lava dome grew in the crater and caused large pyroclastic flows which caused fatalities and damage to populated areas.

 

Polls will close on the 8th July.

177 thoughts on “Volcano World Cup 2018: Quarter Finals

  1. Wait Iceland made it? I thought they were out after losing to Nigeria.
    I know who I’m going for now… 😉

  2. This is all of the deep quakes at kilauea in the past month. The ongoing robust swarm at the mantle source is very telling…

    About 90% of the quakes are above 5 km so they are basically just from the caldera faulting, its the stuff below 15 (which is in the upper mantle) that is the really important stuff as that is caused by moving magma. What surprised me is that while the Pahala swarm is really obvious there are deep quakes all over, one of them just east of kilauea iki is 52 km deep. In a pdf I found it said that a few (~20) deep quakes north of kilauea in 1953-55 were probably the early signs of the 1959 eruption and its very hot lava. If a massive surge of really hot lava comes into kilauea while there are new weak caldera faults and a rubble filled hole in the caldera lid, I dont think much is going to stop it.
    I’m curious as to how the seismic southwest rift will react to all this. I dont think that rift or the existing koae fault scarps, or any of the vents on either of them, are older than 1500 so it seems to mostly or entirely post-date the last really high magma stand in the 1400s. If the ~1000 m3/s eruption rate of the Dec 1974 eruption is any indication then it could be a massive wild card…

    • Major plumbing system changes that could take place during this event are two: drainning and collapse of the ERZ and relocation of the summit vent. The first one we have already talked a lot about but the second will also have implications for mainly SRWZ volcanism if it comes to happen. The largest reservoir of the summit is at the southern rim of the caldera, where the Seismic SWRZ starts if it collapses that will probably be the deepest part of the caldera and a possible new location of the summit main vent, we already know its location is unstable and has moved south since the Observatory Shield times. The Seismic SWRZ is likely to keep the same activity it has had throughout the last two centuries or maybe to increase with a more direct connection to the summit but what I am more interested is in what will happen to the Volcanic SRWZ and Kilauea Iki, if the vent moves to the south the shallow radial connection between the old Halema’uma’u and the two sub-rifts will be lost and activity could fall considerably or maybe even end, both seem to be weak-lines associated to the Kaoiki and Hilina slumps/fault systems but I highly doubt magma will intrude north from the summit, going preferably to the probably younger Seismic SRWZ, ERZ and Koae. We could also see some Koae intrusions and maybe also associated Kamakaia Hills eruptions and that would be really interesting.

      • I think that while the main chamber is still under the existing caldera the vent won’t relocate that much, however if the current eruption somehow drains out the magma chamber entirely and a situation like the powers caldera happens, then the deep conduit will just rise up into nothing and probably relocate a bit further south in the way you describe.

        Kilauea iki seems also to be connected to the seismic southwest rift so I think it will be sticking around for a while longer and there will probably be an eruption in or near it this century, but the volcanic southwest rift (or at least the bit above mauna iki) might be on its last legs and might not make it through another full scale caldera collapse.

        I think if there is a really big surge then unless it happens before the current eruption finishes it will go right up into the caldera and erupt. The volcano is deflated but if the magma rises fast enough it might just directly erupt without inflating much before, and considering all the new weak spots at the summit I don’t see why it would actually be hard for it to find an opening somewhere. Obviously the bottom of halemaumau is the most likely spot but the large fault going next to CRIM is also a risky area and so is the spot just to the south of the caldera where magma intruded in 2015. If it is too big then more distant eruptions on the upper rifts and kilauea iki are possible too.

    • On hotspot strenght Iceland VS Hawaii
      I think… Hawaii is a much hotter and larger hotspot than Iceland.
      Thats how Hawaiis giant volcanoes grows so large so fast.
      And how these islands can build large from the deepest abyssal ocean plain on earth. Hawaiis inner Plume head is estimated to be 600 kilometers wide and 1100 km wide plume swell and having a temperature perhaps 1520 C

      Iceland.. is larger than Hawaii .. beacuse the seas are more shallow. Iceland plume is generaly agreed to be 1470 C I think
      The shallow mid ocean ridge allows Icelands hotspot to lift up more land from the sea. Ridge and Hotspot combination is an excellent way to grow a large island.
      Icelands hotspot.. seems rather cool and “wet- volatile” magmas compared to Hawaiis hot dry plume. Still Holhuraun that came from Icelands hotspot was very very hot 1185 C and fluid.

      Intresting topic : )
      Both Icelands hotspot and the Hawaiian one are very powerful.
      The 2 most powerful oceanic plumes on this planet.
      Whats your own opinion? what plume is most powerful?
      Iceland or hawaii?… I knows Icelands hotspot haves a boost with the mar ridge
      But I say Hawaiii

      • Hawaiian hotspot is currently bigger and hotter but the Iceland hotspot is probably still forming and will likely overtake it when it peaks. Hawaii is probably very old, it is at least 75 million years old (meiji seamount in the Kamchatka trench) and appears to have been already very established at that point so it could date back to the mid to early Cretaceous, or even the late Jurassic. The Iceland hotspot is possibly only 30 million years old, Carl has a post on that which is from some point a few years ago now and is worth reading if you can find it.

        The Galapagos and Afar hotspots are also quite powerful but nothing like Hawaii. Both of them generally fail to produce frequent large eruptions in the way kilauea or mauna loa are able to (although both can produce very big individual eruptions, as sierra negra is showing now). Kilauea erupts the magma equivalent of a VEI 4 every year when it is dominant like it is now, over half of the volume of the pu’u o’o eruption is younger than the year 2000, despite the generally less intense eruption eruption rate compared to the 80s and 90s. Mauna loa is much less active overall (it isn’t usually actually in eruption) but its eruptions are generally very big and so the total amount of lava erupted by them is similar (kilauea probably a bit more overall). Note that kilauea isn’t currently in ‘surge mode’ either, it could be even more active (which is what my theory suggests is in the immediate future)…

        Hawaii is probably similar to what Iceland would look like if it was just in the middle of a plate. Particularly after Maui Nui started forming about 2 million years ago the volcanoes went from being singular radial shields to rift dominated ‘super’ volcanoes (there really just isn’t a better way of describing them, none of the other active volcanoes even come slightly close in volume).

    • Yea I always tought Hawaii was the most powerful. Then Carl is wrong when he says that Grimsvötn haves the worlds highest magma supply.

      That title sourely goes to Mauna Loa and Kilauea

      • Perhaps not a fair comparison. The magma supply to Iceland is easily calculated, as we know the spreading rate and thus know hiw much magma is required to fill the hole per year. That gives 1 km3/yr or so, far in excess of Hawaii. One can argue how much is attributable to Grimsvotn as it shares its magma supply with the othe Vatnajokull volcanoes and with the spreading ridge: it is little more than one channel of the chimney. But hotspot versus hotspot, Iceland wins. However, how much of the magma should be attributed to the hot spot? As this is a spreading centre, the magma would still come up without any hot spot. The hot spot only adds the height above the local spreading ridge. That probably reduces the amount to a quarter, or 0.25 km3/yr. Now we are very similar to Hawaii. Of course, in Iceland only a small part of the magma becomes lava. But we were comparing magma, not lava.

        But in the end the two regions are fundamentally different. Iceland is a warm area attached to the ridge, probably dating from when America split from Europe, 60 Myr ago. Hawaii is an independent hot spot which therefor must have much deeper origins.

        • Are you really soure?
          Hawaii burps out the majority of the worlds lava: Mauna Loa have done 4km3 since 1840
          Kilauea 5km3 for East rift zone and 3km3 for Halemaumau.

          Thats 12km3 erupted since year 1840!
          12 Holuhraun volumes Hawaii have put out in recent history

          • I think that is an illusion caused by the probably at least 80% eruption rate of Hawaiian volcanoes (meaning most of the magma that leaves the hotspot erupts onto the surface eventually). As Albert said a lot of Icelands magma never surfaces. Assuming 0.25 km3 is intruded from the hotspot every year then there has been about 90 km3 of magma that has derived from the hotspot under Iceland since 1840, and if that is 1/4 of the total then the total is therefore about 360 km3. Only about 1/50 of that has actually erupted (about 7 km3, half of that in grimsvotn 2011+holuhraun) though so it gives an illusion of Hawaii erupting way more. There are some other people here that know a lot more about Iceland than I do though and will probably give better numbers, I’m much more knowledgeable on Hawaii as is probably really obvious by now… 🙂

            Also I would add maybe a few km3 to both of those numbers for what kilauea has erupted since 1790 (‘historical time’).
            Pu’u o’o is about 4.5 km3, mauna ulu and 2018 each are about 0.5 km3, 1790 is at least 0.3 km3, 1840 is about 0.25 km3, 1960 is 0.2 km3, 1955 is about 0.15 km3, and the other small eruptions are about 0.1 km3 added up. That gives 6.5 km3 for the east rift since 1790. The 1823 eruption on the southwest rift was also very big, probably at least 0.1 km3 and possibly several times higher based on the affect it had at the summit (the entire caldera collapsed about 100 meters to within 50 meters of the water table).
            The amount of lava erupted at the summit between 1820 and 1840 was about 3-4 km3, and the amount between 1790 and 1820 is about 1 km3 (although it was probably more because a lot of those eruptions escaped the caldera as high fountains, so probably closer to 1.5 km3). The amount erupted between 1840 and 1924 is also about 1 km3, and the amount erupted from the summit after 1952 is about 0.3 km3. That gives about 7 km3 since 1790, and the apparent extra is because there were multiple and sometimes large collapses over that time (1790, 1823, 1832, 1840, 1924, 2018) that consumed some of the caldera and required additional filling, as well as a lot of the stuff before 1820 as well as in 1959 leaving the caldera.
            As you can see, after 1790 and before 1840 there was a LOT of lava erupted at the summit, that is what I call ‘surge mode’.

    • Hawaii can do crazy stuff too.
      1400 years ago Mauna Loa drained an upper chamber or magma column, it erupted in the North Rift Zone the PanaEwa flow have a volume of 6 to 10km3 and was emplaced Very rapidly. Knowing recent large Mauna Loa flows we knows How mosterious it can get. The PanaEwa flow. likley had eruptive rates as large or larger than Laki. The flow covers most of the central North Rift Zone and formed Hilo Penninsula.
      This is the event that formed Mauna Loas current caldera one of the larger recent historical lava flows. If my words are correct here.

  3. Why did you pick an obscure Kurile volcano for Russia? (even if, in all fairness, it’s a pretty cool strombolian erupter, but not a real jaw dropper)

    There are plenty of Kamchatkan middle range stars, some of them quite nice like the ever-erupting Karymsky, a very beautiful symmetrical andesitic cone which displays constant Vulcanian explosions. A Russian Reventador.

    Another good one is Russian Vesuvius, Avachinsky, very near to the city of Petropavlovsk which is in the direct line of fire. A temperamental Somma-type volcano which usually erupts with Strombolian projections and profuse lava flows (the whole crater is filled by a congealed lava lake), but it can explode with significant violence.

    And then, for the next round, where the competition reaches dog-eat-dog level, let’s pull out the real Russian superstars. There are two lesser ones, and two absolute top-notchers.

    Plosky Tolbachik, because it’s the Russian version of Kilauea (with a bit more explosivity, but very similar). This is for me one of the lesser ones, because it lacks the super-explosive behavior of the next 2, and the staggering uber-hyper gigantism and overall “wow” of the last. However, being able to erupt 3 km3 of basalt in one year is no small feat. Well done, N°4.

    Bezymianny, because it’s Russian Mount St Helens. The exact same. Except it didn’t have a name.
    Tough to rank it. It’s in a tie with the next one, because of its pure explosive fury, but it lacks a bit in majesty. Let’s give him N°3.

    Sheveluch, because it’s a cross between Mount St Helens, Soufriere on steroids, a bit of Chaitén, and a sprinkle of Augustine, all mixed up in a mish-mash of andesitic dome-forming goodness and then made angry. Super angry.
    IT’s much bigger than Bezymianny, and although it didn’t reach the almighty power of the 1956 eruption, it’s the gift that keeps on giving, always crackling with Vulcanian eruptions, some of them reaching more than 20 km high. And it’s incredibly productive for a subduction volcano, erupting some very bizzare stuff, adakite which is primitive andesite, pure melted subducted plate. That gives it the N°2. It only has a very bad PR agent because nobody talks about him.

    And Klyuchevskoy. Ah….this one. Man I love this volcano. What a BEAUTY.
    This is the basaltic stratovolcano that would make any other basaltic stratovolcano crumble into tears. 4800 m high. Capable of basaltic plinian eruptions. Central, lateral, fissural, excentric activity, you name it. Covered in parasitic cones like his lesser lookalike Etna. Permanent strombolian explosions at the summit. 4000 m prominence. Makes Mayon look like a dwarf, Villarrica look skinny, and Fuji Yama look like he’s trying too hard. Definite N°1.
    AND IT’S 6000 YEARS OLD????!!!! Extra points.

    I need to calm down I’m getting way overexcited 😉

    • I wanted to save the best Peruvian volcanoes for the final matches should Peru have got through, so I needed to balance out the competition a bit as I picked Huaynaputina for this round.

      • I am still getting some of the polls not showing, this time its the Russia/Peru one. Its platform and browser independent., as its the same on this Linus box as it is on my windows machines.

        • Are they both using the same internet connection? Can you try via a mobile data connection or at another house with a different ISP?

          • It is missing even on my phone’s browser (chrome), using mobile 4g. The other polls are fine as well. Weird bugs are weird.

    • Funny you should mention Sheveluch, it seems it hasn’t erupted since January! Waiting to see if/when the eruptive period that started in 1999 will be declared as finished, like Sakurajima in 2016.

    • If this competition was based on the power of the volcanoes and not what country they are in, it would be Iceland or Russia way in front. The volcanoes of the Americas and Japan are individually large, but Iceland in general is a monster, and so is the klyuchevskaya group.
      Iceland is a tiny fraction below being a genuine flood basalt, and klyuchevskaya behaves like a mantle plume crossed with an already very active subduction zone.

      I think Iceland, Kamchatka and Hawaii are also places where the base magma supply rate exceeds 1 km3 per decade in a relatively small area, although in Iceland and Kamchatka I think a lot of it doesn’t erupt directly and remains as intrusions that might erupt later..

      • Don’t underestimate Japan. There are real beasts there. Aso San may look like a small pimple, but it sits in a 20 km caldera.
        There’s also our beloved Sakurajima, which belongs to the mighty Aira caldera, one of those elusive VEI-7 producers. I really have a soft spot for this volcano, first of all because it’s very active and the vulcanian activity is absolutely amazing to see.

        But the real reason I love Sakurajima, is a technical one. It’s rejuvenating itself.
        In fact, the volcano started out as a rhyodacitic complex of domes, then the eruptions became less and less silicic, until now when it’s about 55% silica, bordering on basaltic andesite. This is a reverse trend compared to other volcanoes which become more and more silicic over time, until the magma becomes so viscous they block up, build pressure and go caldera.

        Since Sakurajima is fed by the magma chamber under Aira caldera, this means the system is constantly recharged by fresh basalt which mixes with the residues of the big VEI-7 eruption to produce andesite.

        We can already see the effects of this by looking at the 1914 eruption. Although it was andesitic, it behaved a lot like what you could find in a basaltic stratovolcano. After the initial explosive phase, the volcano cracked open on its flanks and started producing large, fast moving lava flows accompanied by huge lava fountaining and powerful strombolian activity.

        • I know Japan has a lot of very big volcanoes, especially Kyushu, but the source is nowhere near as productive as Hawaii or Iceland or CKD. In the new decade volcano article on here from a few years ago it mentioned an average supply rate of 0.0005 km3 of lava per year or about 20,000 years between VEI 7s. At the current supply rate kilauea could do a VEI 7 the size of aira every 2500 years. For Iceland, if it only fed one volcano and there was no rift zone, it could easily do that every 500 years, which is a sobering thought…

          I have read that sakurajimas 1914 eruption was largely subplinian while the later stages involved thick magma that formed a big viscous flow. However last year it did erupt some much more fluid looking lava which looked similar to the hot andesite from fissure 17 so I dont know. I would like to see the source for the sort of activity you describe, lava fountaining and fast flows like that is rather unusual for an andesitic arc volcano (although fairly standard for hekla).

          • Hekla is a critter unto itself. A fissure cone-row that is mimicking a stratovolcano.

          • Yes, but in that I was more talking about how its lava is technically andesite but it is fluid and flows quickly and typically erupts as a more effusive eruption than an explosive one like most andesite volcanoes.
            It is quite an interesting parallel with the fissure 17 lava, also an andesite but with little difficulty flowing or fountaining. Maybe most andesite volcanoes (like sinabung, soufriere hills or shevluch) are just erupting cold andesite, and hot andesite at 1000+ C is actually not that different from basalt.

  4. Agung deflated a bit after that strong explosion, so I guess it isn’t building up to a major eruption at least for now. It seemed it was about to return to the situation of last November. Still wondering if the threat of a repeat of 1963 will eventually be realised in this eruptive period. Or at least if the crater completely fills (recent events have filled it from 1/3 full to a half) which could cause a Sinabung-type situation. Anyway, so far since Calbuco we have had potential VEI-4 “scares” from Cotopaxi, Sakurajima, Manam, Katla, Momotombo, Oraefajokull, Agung, and Sinabung, one of these days the next VEI-4 will actually happen surely haha! Maybe (don’t jinx it) the current wait will end up being like the eight years from Rabaul 1937 and Avachinsky 1945 (Paricutin doesn’t really count since there was no Plinian event I suppose) or the six years from Rabaul 1994 and Ulawun 2000. Hmmm, the wait continues…. (*boom* dammit I jinxed it or did I? muahaha!). Something like that 😆

    • Having looked at Jons blog yesterday and what people had to say about it, I think the situation at oraefajokull is far from over, and was also never likely to actually erupt a VEI 4 from that first intrusion. Same with sakurajima, it is probably on a slow road to the big one.

      On the other hand I could say that the current eruption at kilauea is a mid sized VEI 4 in volume or a VEI 5+ in energy release, and the eruption at sierra negra would be in the same size range (honestly wouldn’t be surprised if it is even bigger based on the few pictures). Basically it is the effusive equivalent of when pinatubo and cerro hudson erupted together in 1991 with a comparable energy release…
      The problem is that just like holuhraun both of these very big eruptions will be branded with the impressive title of ‘VEI 0’ or maybe 1 if they are really lucky, while the comparitively insignificant explosion at agung the other day will score at least a 2…

      Global volcanism program also lists the June 2015 eruption of volcan wolf as a VEI 4, I don’t know where they get that from but that eruption was definitely not small so they might have a point. That would make it the most recent example.
      Also extrapolating from the idea that the current situation on kilauea is (very) similar to 1790, then there could be a VEI 4 scale eruption from kilaueas summit in the (very) near future, think 1959 on steroids…

      • For Wolf, it is definitely a mistake, it was really probably a VEI 2, there was a large steam plume with minor ash that went to 50,000ft (that was at the very beginning), but after that it was almost entirely effusive.

        • And for that matter, they also list Tolbachik 2012-13 as VEI-4- it was VEI-3 at best.

          • I guess the question is whether a really high lava fountain that mostly falls as tephra can really be called an effusive eruption.
            Some of the fountains in the 1959 kilauea eruption (particularly the last couple which included the 600 meter one) didnt really add much new lava to the lava lake but created massive tephra fallout to the southwest. Same with many of etnas eruptions, the 2015 fountain at villarica, and also the 1600 meter fountains at izu oshima in 1986. All of these were basalt similar to Hawaii and could have formed extensive flows if they erupted quietly, but they didnt flow, so does that really count as an effusive eruption?

          • @TurtleBirdMan…

            High lava fountains shouldn’t count as effusive eruptions. They’re a spray of fragmented material that falls down as scoria and ash.

            If it smells like a rose and looks like a rose…..

            When talking about Etna and Villarica’s fountaining eruptions, they behave as sub-plinian, with high eruptive plumes sometimes 15km high, volcanic lightning and heavy ash falls. That’s not at all effusive activity.

          • That was the point I was making, really high fountains are more like explosive eruptions than effusive eruptions. I read something that said the 1959 kilauea iki fountains behaved more like a subplinian eruption than a typical lava fountain, namely that the lava was being fragmented at some depth before reaching the surface while in normal fountains it starts near or at the surface. There doesnt appear to have been an eruption column associated with the 1959 eruption but glowing tephra was apparently visible at heights several times higher than the obvious fountain so it was a serious eruption, although there is no confirmed video of the 580 meter tall fountain. That is also what seems to have happened at izu oshima – there were only small flows but the lava fountains were almost 3 times taller than the kilauea iki fountains and formed a tall eruption column that reached almost stratospheric heights.

            I think a lot of the eruptions that produced the keanakako’i ash were probably eruptions like this, except 1790 which was phreatomagmatic. Some of the earlier uwekahuna ash was deposited by actual completely magmatic plinian eruptions though, which was only discovered in 2011…

          • Just having a deep look at it…

            https://youtu.be/HRjLw1x8Q3o?t=143

            Based on current knowledge, you have to be utterly NUTS to stay where they were. This is no mere “lava fountain”, that is a gas jet spewing zillions of tons of scoria/basaltic pumice very high. That’s a subplinian activity.

            https://youtu.be/HRjLw1x8Q3o?t=260

            I’m surprised there was no lightning in the plume… Yet ballistics are falling all over the place.

            Just imagine for one second if the column collapsed on them or if a directed explosion occured towards them…

            https://youtu.be/HRjLw1x8Q3o?t=318

            You can see stuff already beginning to cascade from the lip of the crater…

          • I came up with the term ‘ultrastrombolian’ to describe events like that. It is the point roughly half way between hawaiian and subplinian activity. It is called ultrastrombolian because it is not really the same as a hawaiian lava fountain but it is continuous unlike a strombolian eruption. Typically there are not large flows directly from the fountains in these eruptions.

            These big lava fountain eruptions are common on basaltic stratovolcanoes like etna (as your linked videos show), but I think kilauea is one of the few shields known to erupt that way, along with some of the Galapagos volcanoes. These might be borderline cases though as significant lava flows were generated by the 2015 eruption from wolf, and the kilauea iki eruption did seem to be more fluid at times, but whatever eruption sent scoria into Volcano 500 years ago was probably a genuine example.

  5. The last few houses at Kapoho are about to go. I wonder if they’ll rebuild this time, like they did after the last eruption destroyed it? It looks like part of the delta flow is favouring the northern edge.

    • Realistically they shouldnt, but because the blocks of land are still under posession I think at least a few will build on the new lava. Same for the parts of Leilani estates that have been buried (except maybe for the cinder cone which might be kept intact as a monument) and the properties buried by pu’u o’o lava in Kalapana and Royal Gardens.

      • I remember an interview with the local Mayor of that area (I think he was the Mayor)
        He said he and other officials did not want a rebuild but were pushing for a re-location area further North near the coast, he even showed a proposal map. He was also proposing turning the whole area covered by lava into a conservation/tourist park with viewing areas and trails, as he referred to a previously covered area to the West.
        I think it was, Big Island Video News, on YouTube.

    • That is expected now that the flow here has gone underneath. It spreads out, thickens the lave flow and pushes out along the edges. This area was likely to be affected by that. It is not happening on the southern side because the lava does not reach as far, and because the land is higher against the old cone.

  6. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/97JB01426

    This is some very good analysis on the 1790 summit eruption. It is from 1997 so some of it might be a bit outdated compared to current knowledge, but it is interesting nonetheless.

    Apparently the eruption started on dry land but had a pause which allowed the vent area to subside below the water table before it resumed under the resulting lake which formed. There is no soil layer or any other evidence of a significant gap between the early phase and the main explosive eruption, so this lake must have formed in only a few weeks, which suggests the reason why a lake doesnt exist in the currently formign crater is because it isnt actually deep enough to intersect the water table. After the explosive eruption there were more lava fountains, and it also included some lava erupted from outer caldera faults, although I think only some of that is sort of visible now near the Dec 1974 fissure. Again, this happened less than a year after a major rift eruption and draining event comparable to the current eruption, so the normal assumption of a prolonged inactivity after a draining event is not really applicable to kilauea when it is in a heightened state of activity like it is now.

    The descriptions of 1790 given to Ellis in 1823 indicate that the major eruption was probably close to stratospheric in height, and it was largely new magma as the eruption column was reportedly glowing (some of this could be from lightning though). This is again evidently very different from the 1924 explosions, or from what we have observed in halemaumau now, which were vulcanian eruptions driven by build up of gases under the surface and contained little new magma. It also seems to contradict a lot of the general information about how this eruption was a result of water contacting hot rock in a collapsing caldera.

  7. Also an even more important and completely up to date, a new paper released by HVO/USGS last week.

    https://volcanoes.usgs.gov/vsc/file_mngr/file-184/Summit%20scenarios_7-5-18.pdf

    It seems like HVO has also seriously considered the similarity between 1790 and now, which means way more than when I talk about it because while I am an anonymous avatar on a website who has maybe been seen by a few thousand people (not sure actually how much traffic this site gets), they are literally the #1 primary source of anything to do with kilauea and millions see their work every year, especially now. If they are catching onto this idea then suddenly it is a reality and not a theory.

    Honestly I thought kilauea would just keep going on at its slow pace for years for the rest of my life, eventually abandoning pu’u o’o and just overflowing the summit. I never thought that within a few months it would be giving holuhraun a run for its money or threatening to return to huge violent eruptions again. This will really screw up the base model of how basaltic shield volcanoes should behave…

    • “More powerful explosions accompanied by ground slumping and ash emission
      began on May 16. The most notable explosions – and the type discussed here
      – have produced relatively high levels of ground shaking, are apparently associated with abrupt pressurization of the magma reservoir, and through late May emitted relatively vigorous ash plumes. We here refer to these
      as Collapse/Explosion (CE) events
      .
      Early CE events (before late May) ejected ash and gas to heights above 25,000 ft. and large (ballistic) fragments tens of centimeters in size to the area immediately surrounding the vent (Figure 1). Observations and preliminary models suggest that these explosions may have been caused not by interaction of magma with groundwater, as previously believed to have occurred at Kīlauea in 1924, but rather by exsolution, expansion, and release of gases which were dissolved in the magma. CE events have occurred semi-regularly with repose periods (time between events) of roughly 1/2 to 2 days. Seismicity increases in the hours preceding explosions, leading to cycles of earthquakes that are felt in the summit area. The mechanism producing CE events is not well understood. “

  8. youtube.com/watch?v=66Q5jlq8fOU

    Apau Hawaii tours this morning.

    Looks like the hot lava has scoured deep an is largely out of sight. like a cave erosion,in water not lava. In my opinion. Still flowing alright,

    • After taking hours to check and post it they now decide it was very wrong. Latest

      M 3.7 – 5km WSW of Volcano, Hawaii
      2018-07-06 18:42:25 UTC 19.416°N 155.277°W 0.7 km depth

      Interactive Map
      Contributed by HV1

      • For all. Picking seismic waveforms isn’t the prettiest thing. It’s half science and half practiced art. Get the pick off by a microsecond and the solution can move by miles.

        • Someone commented in a youtube chat that they thought this was maybe an automatic estimation that had been held back but got mistakenly released as reviewed while they were in the process of putting out the real manually reviewed version. Their reasoning for that was that the location uncertainty was far too high for a true manual review and the correction came shortly afterwards.

          I don’t recall the original uncertainty myself but if it was as they said then that sounds at least another possibility.

          In case anyone wonders I fully appreciate USGS/HVO and the immense workload they must be under at the moment.

  9. I have been thinking recently about the eruptive history of Kilauea, these last days or weeks we have speculated about some things like of how Puu Kaliu eruption possibly followed Kane Nui O Hamo shield formation at the middle/upper ERZ (Puu Kaliu as an analogue to the current eruption and Kane Nui O Hamo to Pu’u’o’o) and given an aproximate date for both eruptions of 1300, the publications I have seen on the matter also place both eruptions being less than 750 years old. But I was having some problems with this, the first is why when 1790 was a smaller eruption than Puu Kaliu it was able to produce an important caldera collapse and associated explosion event while Puu Kaliu if happening around 1300 wasn’t. Another problem is the probably long time interval that must separate Puu Kaliu from the flows dated in 490 BP, turtlebirdman talked about how the picrite eruption that overlays Kaliu flows probably came much more time after than 50 years. This is because after the eruption of 1790 (analogous to Puu Kaliu) 50 years passed before the 1840 picrite eruption took place, three picrite lava eruptions are exposed at the LERZ (The one that followed Puu Kaliu, Halekamahina and 1840), the thing is that the 1790-1840 effusive phase at the summit wasn’t even able to overflow the caldera while the effusive phase following Puu Kaliu must have included the Observatory Flows that completely overflowed the previous caldera and maybe Aila’au too, it may have taken a few centuries for the two to form, If 1840 can be compared to the picrite eruption following Kaliu then a long period of summit activity must have happened between it and Kaliu, and another relatively big eruption happened afterwards the picrite eruption and before the 490 BP flows, and this is just in the central part of the LERZ, I think this large number of events and the voluminous summit activity before 1500 sends Puu Kaliu much before 1300. Another thing that was bugging me is that while at the LERZ there seems to be three phases of high activity in the 1250-1790 period: Puu Kaliu and previous eruptions, the one that includes flows dated at 490 and 440 BP and the last one that includes Puu Honualua dated at 350 BP, Kapoho Crater, 1790 and others. While at the upper portions of the ERZ only two phases can be distinguished: Kane Nui O Hamo and Puu Huhulu-Heiheiahulu.

    After some headaches I think a way to solve the three problems and that doesnt come into conflict with other things is that Puu Kaliu is older than what we had thought and that where some old studies (but the only ones that get into this) place it, I think it could have happened around 1000 AC just before the last of the explosive events grouped in the Uwekahuna tephra, the one that I think is called Kalanaokuaiki Tephra and before the Observatory Shield actvity which is thought to have started shortly after this date, that also means that Puu Kaliu was not associated to Kane Nui O Hamo which may have happened more close in time to the 490 BP flows or not, both Kane Nui O Hamo and Puu Kaliu havent really got absolute or relative ages that can bound them to a determinate date so that leads to speculation. This is something to consider for the aftermath of the Leilani eruption, it is only a possibility but given that the current eruption may have already surpassed 1790 in volume that means it could be foretelling future summit explosion or high fountaining events and even more if Puu Kaliu really preceded the Kalanaokuaiki tephra.

    • Regarding the 50 year gap between 1790 and 1840, I was more meaning that the summit draining event in 1840 might have happened before it would be expected to, not that there will be a large picrite eruption 50 years after every large tholeiite eruption. If the previous history of kilauea was as well known in 1823 as it is now, then anyone there at that time would have assumed this activity is going to fill the caldera to overflowing and be the new aila’au, but that never happened. Likewise if the current eruption is equivalent to something like 1790 then the big summit draining eruption equivalent to 1840 might not necessarily happen for a while. The main reason why this eruption is bigger than the 1790 rift eruption might be because in 1790 the caldera was still deep, not deep enough to contact the water table (the summit eruption started on dry land) but much deeper than the caldera of April this year. This might have the affect of the large mass of the caldera floor falling into the chamber a bit more and pushing out more magma, pu’u o’o was also a bigger eruption than heiheiahulu so this period of activity could have just been bigger in general than the 1700s one. That could indicate the summit response might be bigger after this too, as you said…

      Also while the eruption itself isn’t that well studied, or at least well published, pu’u kaliu is at least well dated, and it happened around 1300 with a 50 year margin of error, or close in time to kane nui o hamo and maybe just after the earlier caldera had reached a point that it could overflow (but before the main overflows). If pu’u kaliu was really much older than that I think HVO would have noticed. If it was as big as the current eruption is then it would have collapsed the summit to some extent and could have also formed some of the chain of craters (although some of them post date aila’au so this is very rough). After that it appears activity went into overdrive again and then the major summit overflows happened not long after.

      It is possible that the pu’u honuaula eruption was the initial activity that opened up the rift, something like in 1955, and then the kapoho cone eruption might have been more like the 1960 eruption. These events were more than 5 years apart but both were maybe a lot smaller than the current eruption, despite making sizeable cinder cones. The rift seems to have been more active in its lower sections during that period than it was between 1955 and now, maybe that also has something to do with the relatively larger eruptions of this period than the 1600-1790 one.

      As for completely destroying the summit chamber with a total deep caldera collapse, that isn’t going to happen now, the eruption is too high up in elevation so even if the summit drains out entirely up to level with the eruption (making a caldera 700 meters deep) most of the magma chamber will still be there. There must have been a really huge deep intrusion and hidden submarine eruption that formed the powers caldera, because that apparently did destroy the magma chamber if most of the eruptions were sudden explosive eruptions of very primitive lava, and lava flows didn’t restart for over 1000 years afterwards.

      • Just a random comment I have been intending to make for a while.

        I imagine there was a significant volume of magma inside kilauea which had been there for a while but which originated from significant depths. I also imagine that this magma contains significant potential volatiles that are capable of coming out of solution should the pressure drop.

        I imagine that at least in part it is this mechanism which is powering the effusion of lava.

        If the pressure drops to the point where some dissolved fractions convert to gases abruptly (eg like a phreatic, but this need not be H2O generated) then an explosive event could occur.

        It also seems to me that effusion vs explosive is related by how quickly the magma-gas mixture can exit. If it exits through a small hole(s), pressure will fall relatively slowly and safely but if there is a large hole, eg caused by collapse destroying part of the chamber roof, then depressurisation may be explosive.

        Just in passing its worth remembering that for magma, even a few hundred meters of reduction of column height is a very very substantial pressure drop indeed.

        • SO2 only leaves the magma at depths of less than 1 km usually. The SO2 measurements show levels equivalent to before the summit eruption happened, so I guess anything that happens would be considered a new eruption, but that also means there is no magma under halemaumau at less than 1 km. Water leaves the magma at a much greater depth including in the magma chamber itself but I think in Hawaii most of the eruptions are relatively anhydrous and water only plays a role in phreatomagmatic eruptions. CO2 is similar to water and this is also detected in fumaroles around the volcano.

          Basically at this point it is equivalent to being only a flank eruption again.

      • I dont recall HVO ever giving a date for Puu Kaliu, the only thing that is known as far as I know, and I have tried to find all information possible on Puu Kaliu, is that it is older to the 490 BP flows which were dated around 20 years ago or more, so it would be 510 BP now. There are two other flows between Puu Kaliu and 490 BP and it is probable that Aila’au and at least a large phase of the Observatory Flows happened during that interval. The most likely reason for Aila’au to have formed there is because there was a large shield that had reached its maximum possible development and there are no overflows from the Observatory Shield after 1500, but still I am not sure about when did Aila’au erupt, there are a lot of different publications that give different dates.

        • The ~1300 date is on every LERZ lava flow map I have seen.
          It predates the major summit overflows too, although not by a long time.

          Also I finally found the original source I read for the kulanakauiki eruption. I guess they knew about it way back in 2001, but the main research was published in 2011.
          I didn’t realize how far it actually reached though, rocks big enough to kill you on impact landed as far as the south coast, and the eruption column reached the stratosphere 30 km up. They dont mention pyroclastic flows or surges but considering surges dont really leave deposits I would be surprised if there werent any. There is no eruption volume given as that is probably very hard to estimate with the limited exposure, but it was probably easily at a VEI 5 intensity if not an actual VEI 5 full stop. That isn’t something that will happen after the current collapse but it really shows how volcanoes can and do erupt in ways that we think they shouldn’t be able to. This eruption was south focused but something like that focused to the northeast could be a very dangerous situation.

          http://archives.starbulletin.com/2001/01/04/news/story2.html

          Also, I looked up the aila’au eruption and some of our pictures are on the google maps front page… That actually gives a really serious chance of someone from HVO seeing our discussions. Hello if you are 🙂

          • But I dont know where the ~1300 date comes from, Puu Kaliu has to be older than the 490 BP flows because it underlies it but it doesnt overlay any dated flow so I dont think there is a maximum age for Puu Kaliu. I dont know if maybe paleomagnetic studies were conducted but I dont know how accurate are those for eruptions so recent, vegetation cannot be used for flows that are older than a few centuries, 300? at max because everything begins to look the same before that, at least in the wet areas.

  10. @ turtlebirdman & Thedustdevil; I am really enjoying following along in your back and forth discussions about Hawaii. As a general rule, I perceived Hawaii to be a bit of a bore, but I have begun to find the place a bit more complex and intriguing from the conversation. Well done, and please continue. 😀

    • If I’l be honest I was starting to find it a bit boring too, despite it being a long term plan to go there, but after looking into the history and finding out how significant this sort of eruption is, I’m probably never going to find any other volcano as interesting ever again, It is kind of like Iceland condensed into one volcano…
      Among all of my research, it also made me realize how dangerously underestimated hawaiian volcanoes actually are, especially as at least 90% of people know it through what was actually a very unusual eruption with only 2 (maybe 3) comparable examples in the last 2000 years. That is compared to the at least 50 large to very large pyroclastic eruptions, 500 years of frequent extensive summit overflows, and probably well over 1000 brief lava eruptions over that same time period. I think kilauea has even erupted more tephra in the last 2000 years than the entire cascade range over the same time period.

      Effectively the amount of information the average person knows about kilauea would be like them assuming all of mt st helens’ eruptions are like 1980 and saying it cant erupt any other way because it hasn’t been observed doing anything else (last part not actually true but you get the idea).

      • VC didn’t do much on Hawaii, partly because of the lack of variation (Pu’u’O’o was a bit long lasting), and partly because it was difficult to add anything to what HVO had already written. This eruption has provided us with more material, and much more variety, that we could have expected! This is becoming a once-in-a-century event. But it has shown that the predictability of Hawaii came from ignoring its history.

        Hawaii is not Iceland. A spreading rift behaves different, and a Hawaiian Eldgja or Laki would be unexpected. But I have learned from this that the spreading off Hawaii, leading to the M7 quake, gives a stress regime that is quite similar. Hawaii still lacks a Hekla though.

        • It is more that elements of what can be seen in different parts of Iceland are all present at kilauea, except the silicic eruptions. However after this eruption it can be said to not only erupt basalt anymore with the andesite at fissure 17, and that could have implications for future activity. I guess fissure 17 is kilaueas hekla 😉

          It could actually erupt hekla-style if things really break down at the summit though. I somehow think that these early warning signs thaye are talking about are going to be very late warning signs in reality, magma has to rise only a few km through weak rock and faults, and most past summit eruptions, even big ones like 1959 and 1968, have been preceded by only a few hours warning so things are going to be tense. The best case is an immediate re-eruption in halemaumau with no inflation, anything else could be a big problem especially if the same sort of surge in magma supply happens as what occured in 1790.

          Also I would consider this eruption a once in 1000 year event, none of the eruptions since at least pu’u kaliu 700 years ago are as big as this one, and the only things significantly bigger are big shields like pu’u o’o. The current eruption is as big in volume as mauna ulu but in 1/30 the duration…

          • And that points at a potential resolution of the VEI scale vs purely extrusive eruption categorization problem. Adding a time element to the volume ejected. Mastin et al and the preceding work by Sparks both calculated a mass ejection rate based on the heat (energy) content of the ejecta. For an explosive plume, this is manifest in the column height. The higher the ejection rate in energy quantity, the higher the plume. Effusive magma also carries a thermal heat load in the mass that comes out of the fissures, so on a pure energy standpoint, they could be compared to each other on the same scale. The greatest difference would be in the energy per unit time, and that could offer a way to place them all on the same scale for comparison and allow the destructive explosive eruptions to stand apart from the more “sedate” effusive eruptions. (though I think lower Puna may differ in opinion of the term of “sedate.” Especially with the fissure 8 torrent of magma raging like a river in flood stage)

          • We need to be a bit careful about the 1 in 1000 years. We do not have a complete record that far back because much has been covered by later flows. We also could not have known (for instance) that the lava at Kapoho and the early flows to the south came from the same eruption. So it may be true, but we don’t know that.

          • I guess that is true, but it is definitely a more than 100 year event. The last eruption that is comparable in size is 1840, but that was almost a black swan and had a completely different mechanism to the current eruption. The last eruption with circumstances that are similar is the 1790 eruption, and before that is pu’u kaliu in ~1300, which is probably the closest in size and appearance. Pu’u kaliu and 1790 also possibly have a similar origin to how this eruption happened given their close age to kane nui o hamo and heiheiahulu respectively, in which case this eruption now might follow after pu’u kaliu and go into more episodic geyser-like eruption in its waning days and this eruption could go on for quite a long time…

            Also does anyone have a number for how many visitors this site gets in a day? Some of our stuff in on the front page of google images for kilauea so if there are a lot of visitors there is actually a really good chance someone from HVO has seen these discussions 😀
            I am speculating here but maybe they read mine and thedustdevils comments and that got them thinking about some of these things 🙂

          • As of right now, 139 for today, but generally it is in the range of 2000 to 3000 per day. And yes, there are a few clicks listed as volcanoes.usgs.gov

            That’s about all that I am willing to state. I don’t have explicit permission to reveal anything more than that.

          • HVO definitely would not use our discussions as their source of information. But they are interested in the public and have been very responsive to questions and suggestions by the public, including from us. At VC we can freely speculate, and sometimes we hit the jackpot – and sometimes not. The IMO also always was interested in what we had to write. At the time of Holuhraun, there was no good information source available apart from the doomsday press, and VC landed that role. Nowadays, there is much more available but it remains difficult to separate the good from the bad. We always have a big spike in traffic during a significant event, and it seems we are seen as a useful resource.

            The VC posts are widely read. We have around 4000 unique visitors per week. Fewer people participate in the discussions, obviously. The numbers Lurking quotes excludes commenters, by the way.

          • Oh no I know HVO wouldn’t use us as sources (it would basically be them referencing themselves…) but it has probably been seen by them and could have got someone thinking about the matter. Well at least it would be cool to think that I had something to do with it even if that is unlikely 😉

      • I am really enjoying this eruption and all the discussions here at VC. Right now I dont think I will ever find any other volcano to be as interesting as Kilauea either,

    • I have to agree with GL here. Your discussions have been informed, researched and fascinating! Thank you!

  11. I finally found the picture again, this is the 580 meter tall lava fountain of 1959. A repeat of this along any of the caldera faults is a not unlikely scenario in the next few years. Most likely it would be in halemaumau or to the south but if it is further north and without trade winds it could get scary if you live in Volcano…

    Also, if things really go nuclear, something like this could happen.

    This is (very) unlikely but not impossible

  12. Nice photo of Las Cumbres collapse.
    The Galapagos shield volcanoes are quite diffrent from Hawaiis in apparence and structure.
    The Galapagos Shields are smaller, and more rounded. Eruptions tends to occur in ring faults around the calderas. Many shorter eruptions are the reasons for the relativly steep slopes of the galapagoian shields.
    Galapagos calderas are often quite large and can be very deep. La Cumbre, Cerro Azul, Volcan Wolf and Volcan Darwin looks like this. I think this apperence is unique to Galapagos islands.
    Isabela and Fernandina islands are superfun to explore in Google Earth

    • That is true, but the 1968 eruption and collapse at fernandina were similar to kilauea now, a radial eruption and central caldera explosive eruption. The metaphor for describing that eruption as ‘nuclear’ actually isn’t an exaggeration either, the June 11 explosion was as big as castle bravo. Even for a silicic volcano in major eruption that is huge, let alone something from a basalt shield, really shows the power of water flashing to steam at 1000 C. That eruption also had high temperature base surges and was erupted through a caldera lake like what was predicted to exist at kilauea in 1790 and probably before 1000. The fernandina collapse is most likely the best recorded comparison to the 1790 summit events at kilauea, and potentially for the current eruption too.
      In 1790 kilauea also erupted lava from an outer circumcaldera fault on the southwest rift zone during the later stages of the explosive eruption, and it erupted lava fountains taller than the ~600 meter deep caldera both before the explosion and several times afterwards in the next decade, also from caldera faults. This activity is actually quite similar to the sort of eruptions the Galapagos volcanoes have, especially volcan wolf. I saw a source that the fountains at wolf in 2015 were over 800 meters tall…
      Some of the older Hawaiian islands, particularly Kauai, were also probably similar to the Galapagos volcanoes in shape, as they have large calderas and no dominant rift zones, a few older Galapagos volcanoes also resemble the Hawaiian volcanoes too.

      The Galapagos volcanoes are probably the most underrated volcanoes on earth in my opinion. In the recent and presumably ongoing eruption at sierra negra, lava flowed 14 km to the sea along the entire north coast of the volcano, all within a few hours. It is likely bigger than any eruption mauna loa has ever done and probably even bigger than holuhraun was at the equivalent age. There are vents erupting 300 meter lava fountains along a 10+ km long fissure, and a single large flank vent further down had an over 500 meter lava fountain for a few hours… I believe it is way less now but still, it’s insane to me that more pictures don’t exist, it is something that literally happened only 2 weeks ago…

      A year ago I would have said the opposite, but basaltic shield volcanoes are definitely 100% the most interesting volcanoes, and are far more variable in their eruption style than most sources give credit for. Most silicic eruptions are either small or completely huge, but basalt can span the entire spectrum of volcanic activity (except maybe for peleean lava domes).

      • “June 11 explosion was as big as castle bravo”

        15 MT or without the heat and nuclear radiation 15 000 000 tons of Trinitrotoluene (TNT)
        The great miscalculation of the nuclear test age, it had a yield 250% greater than designed at 6 MT

        You tube video:- youtube.com/watch?v=fd1IFjBNNVo

        Hawaiian volcanoes are definitely not boring.
        That June 11th must have been frighteningly exciting, to say the least.

        • Russel kilauea didnt do that eruption, just in case you didnt know or misread it. That eruption was on fernandina, from la cumbre volcano in the galapagos. It is an example of how violent an effusive basaltic shield volcano can be. The idea is that kilauea is capable of doing that too, and it likely has done so at least once in the last 2000 years.

          Also technically kilauea is a stratovolcano because it is made of layered tephra and dense lava. The same is true for the summits of most basaltic shield volcanoes actually. Ambrym is actually mostly made of tephra, so while it is basaltic, has fluid lava and is shield shaped, it clearly isn’t effusive…
          I think global volcanism uses the idea that a volcano that is steep is a stratovolcano and one that isnt is a shield. It is actually very misleading as it assumes all flat volcanoes are effusive and ‘safe’ when that is very untrue.

          • I did realize but omitted to say in my reply, my proof reading is bad!
            The stratovolcano by its nature has the water table mixed up on diferent levals deep within.
            Lowering of lava levels has caused explosive eruptions before in Hawaii, sounds pretty dangerous.
            If all the lava pouring out of fissure 8 lowers the lava table below the water table, I presume the Kīlauea Volcano Summit caldera will be the point of violent outgassing if not blocked or explosion if blocked.
            Hope its not 15MT equiv’.

          • The current depth of the crater might be just above the water table, so I don’t think a lake is going to form at the bottom of it and any eruptions in the crater as it is now are likely to be entirely effusive like in pu’u o’o. If pressure is allowed to build, then that makes things a bit more interesting, as that could allow some of the rock to saturate. That won’t cause a really violent explosion but will probably be dangerous to observe. The higher pressure in the magma chamber is also likely to increase the risk of a high fountain.

            However if the collapse continues for another 2 months or so as is considered a more likely scenario by HVO, I think some of it is eventually going to go below the water table unless a big avalanche from the side fills in the deep pit. I actually have no idea why the explosion at fernandina was so big (it is actually way short of castle bravo though, which I thought was ‘only’ 5 Mt when I wrote that other comment – the explosion at fernandina was 3 Mt), but I don’t think it was caused by magma simply contacting a lake otherwise there would be many such events in recorded history and any volcano with a lake would be a massive problem. Fernandina and kilauea are quite similar so it could be that the explosion was actually caused by a really huge lava fountain through the lake which exposed a lot of surface area at once (the most likely mechanism for kilaueas 1790 summit eruption). There are a lot of similarities between the two volcanoes so while the possibility is currently very low a major explosive eruption at kilauea can’t be ruled out because if it does happen then basically anywhere out to at least 5 km beyond the caldera is at risk of high temperature fast moving base surges (the kind that will set you on fire and send you flying)…
            Pyroclastic tephra and surge deposits have been found in the walls of pauahi crater dating back to when the previous caldera existed before 1000 AD, and pauahi is further from the summit than Volcano or the golf course, so there is a lot of inhabited areas at potential risk.

      • There are also those volcanoes that combine basaltic and silicic lavas, which would basically be the ones with rift zones that produce basalt eruptions and a central dome-stratovolcano complex, like Tenerife in the Canary Islands or Payún Matrún in Argentina. It depends on if you consider these to be basaltic shield volcanoes or not, but I think the predominant lava composition is basaltic and the general morphology is shield-like for both volcanoes, The global volcanism program considers Payún Matrú to be a shield but Tenerife to be a stratovolcano.

        Payún Matrú would be a good example of a shield volcano capable of producing eruptions that range from a VEI 6 trachytic caldera-forming eruption to a 181 km long basaltic lava flow that is the longest known Quaternary lava flow.

        • Payun patru is a really interesting volcano. At least to me it looks very similar to the mcbride/undara volcanic field in northern Australia. Both have infrequent but often very large and extremely extensive lava flows, and are very flat (mostly) and occur in places where there isn’t really an expected large source of magma.
          Payun matru probably erupts a bit more often on average (maybe every 5000-7000 years or so vs ~10,000 for mcbride), and has a much more varied composition and seems to have at least had a magma chamber at some point, but there are a lot of similarities.
          It could just be that the main activity at mcbride is younger so it has yet to become a larger and more obvious volcano like payun matru, it is possibly on the verge of becoming Australia’s first large polygenetic volcano in 15 million years.

          I guess really wide flat volcanoes like these are sort of the half way between normal volcanic fields and large scale igneous provinces. It would be quite a sight to see either of them erupt, with lava flowing 150 km from vents far beyond the horizon.
          I think both are above areas of weak extension and might be caused by the same sort of accumulation of magma as what Carl’s Norway post went into.

    • Useful. Thanks for that MJF! Interesting reading.

      It’s also interesting to read that reticulite fell out onto the golf course 500 years ago. I wonder what the golfers of the day felt about that? Adds new meaning to scoring a hole in one when the ball drops into a huge caldera on the 9th hole.

      Sorry, I’ll get my coat…

      • No coat needed. I’ve made worse jokes here. Concidering there is a golf course up there, it’s a reasonable jab.

        • So you thought his discussion of the matter was up to par? Perhaps others would consider that the grass would be greener elsewhere. Do you think that an eruption would be a major driver to evacuate the course?

          • “Do you think that an eruption would be a major driver to evacuate the course?”

            Probably not, unless scoria were raining down on them.

            Golfers tend to golf, no matter what. In Florida, the makeup of our native forests is dictated by our weather. Trees more resilient to lightning strikes and the resulting small brush fires have an advantage. I’m pretty sure that if you comb through our lightning mortality list you will find that several of them are from players trying to finish out that last hole before the rain starts.

            “Yeah, lets just stand out here in an open field and hold a metal rod up in the air…”

            Charles Steinmetz (a contemporary of Nikola Tesla in electrical engineering) could have told you that was a bad idea.

            {Steinmetz did a lot of practical research work in lightning mitigation. even going as far as blowing up model buildings and houses built on discharge plates and zapping them to see what got hit first.}

            Arcane tidbits of knowledge like this come from spending hours wandering around the 500-600 area of public library killing time.

            Steinmetz was every bit as much a “Lord of the Lightning” as Tesla was. (referring to the line in Edison’s Medicine by the group Tesla)

            While Tesla is renowned for his theoretical work and ideas, Steinmetz worked on practical implementation of some of those ideas, though he did not suffer the PR attacks and slander of Edison.

  13. HEY YOU GUYS!! i’d be happy to hear anyone interpretation of what is going on with the lower rift camera at the moment…. looks VERY different and i look at it a lot (i have no life) Best!motsfo

      • Have You been watching it?? i’ve never seen the main glow totally snuffed.

        • It seems that it is rainning really strong right now and rainy season hasnt even started there, no wonder a lake formed at the 1790 summit caldera in a few weeks.

          • Though this rain is probably being intensified by the updraft above fissure 8.

      • i’m thinking lava breakout because the glow in the river had a funny short armed ‘star’ shape and then when huge glow with main vent obscurred.

        • it’s clearing now but i gotta go to bed…. it’s 4am and i can’t even hit the right keys… Night, All or Good Morning or Afternoon wherever we are… Best!motsfo

  14. I did some calculations to find out how big this eruption is in terms of energy. I’m not great with maths and I might have got some stuff wrong, but I dont think I did, so lets start 🙂

    According to google, basalt requires 840 joules to increase 1 kelvin in temperature per kg. That means a 1 kg block of basalt will also release 840 J to cool 1 K. I assume the lava becomes dense rock because it is easier, so there are 3100 kg of basalt in a square meter. The lava has to cool 1125 K to go from 1150 C to 25 C.

    That means each square meter of lava has to release 800 x 3100 x 1125 J to get to room temperature. That is 2,929,500,000 J or 2,929,500 kJ. Now there are 450 million of those square meters, adding up to 1.32 x 10^18, equivalent to 315 megatons of TNT or just over 6 tsar bombas…

    Mt st helens 1980 was a decent VEI 5 of about 1 km3, and that was an estimated 24 megatons, or 13 times smaller… The current eruption on kilauea is equivalent to an eruption of just over 13 km3 of ash, a solid VEI 6, the equivalent of the novarupta eruption, and over 50% bigger than krakatoas infamous island-destroying explosion on August 27 1883.
    It gets even better than that too. Kilauea was erupting about 0.15 km3 of lava per year on average during the pu’u o’o eruption. Putting that into the formula would give equivalence to an explosive eruption of 4.3 km3, which is just short of pinatubo. Basically kilauea has been erupting with the energy equivalent of a borderline VEI 6 every year for about 30 years, I dont think any other volcano on earth can even dream of competing with that number while erupting with the frequency that kilauea does.
    Not bad for the ‘worlds most gentle volcano’…

    For comparisons I used the same numbers but for some other huge lava flows. With the 1.7 km3 volume of holuhraun it gives an energy equivalent of 1190 megatons. This is equivalent to an explosive eruption of about 50 km3, which is a VEI 7 as big as tambora…
    With the volume of the skaftar fires (only the volume of the lava, there was a lot of ash too but I dont know how much), it came out to 9802 megatons. This is equivalent to an eruption that is 408 times the size of mt st helens 1980, or much larger than any actual explosive eruption on earth in the holocene… I said in an earlier comment that Iceland would be capable of an eruption the size of aira caldera every 500 years if it was a single volcano, looks like I was technically right…
    The biggest lava flow anywhere on earth I could find a solid volume measurement for is the roza flow of the columbia river basalt, which has an estimated volume of 1000 km3. This would be roughly equivalent to an explosive eruption of 30,000 km3, I dont think a single explosive eruption that big is actually possible but if it was it would be a mid sized VEI 9.
    I really have no idea what sort of crazy number it would come up with for the original volumes of the biggest eruptions from the Siberian or Deccan traps (or the Otong Java plateau…), but it is beyond anything short of a major asteroid impact. It makes almost every explosive volcano look like accidental and superficial side affects of a bit of water getting into the subduction zone 😉

    I actually really hope HVO or IMO sees this comment, even they might be surprised by these numbers 🙂


    GL Edit: My apologies for intruding, but “Kelvin” is a unit. Not “Degrees” on the Kelvin scale. An increase of one Kelvin is equivalent to an increase in one degree Celsius. The difference in the two is that Kelvin is an absolute scale, Celsius is skewed to correspond to a couple of well known physical transitions in water. This is why Kelvin is so well suited to energy calculations.

      • If you calculate the tephra volume for the explosive eruptions and not the DRE, the numbers seem a bit wrong. Pinatubo was 10km3 Tephra, which is way bigger than the assumed 4.3km3 Kilauea put out.

        • The dense rock equivalent is more fair on effusiive eruptions. It is true thaterupted lava is usually not quite as dense as the theoretical maximum but the density of tephra is much lower than the rock it is made of so it tends to skew the number to being larger than it really is. The energy of the current eruption at kilauea could theoretically turn 4.3 km3 of solid rock into tephra, which is very comparable to pinatubo especially as the volume of ash eruptions is always less certain due to ash being a not-solid material.

          • I understand that you’re calculating with energy release….but to make the numbers comparable, the thermal energy release would also be included in calculating the explosive eruptions.

          • In that case the current eruption as of right now has a thermal energy potential of 1.31×10^18 J and that number is probably going to be significantly bigger by the end of the eruption.

            Holuhraun had a thermal energy of about 5×10^18 J

            Skaftar fires had a thermal energy of about 4.1×10^19 J

        • That isnt the volume of what 0.15 km3 of lava would be in tephra, that is the amount of energy that kilauea emmited in an average year of the pu’u o’o eruption translated to how much tephra that amount of energy could cause to erupt using the same magma statistics as what mt st helens had in 1980 (dacite at ~900 C). I guess that is actually a fair bit lower than pinatubo (I misread the 5 km3 number as the amount of tephra when it was the dense magma equivalent) but considering that has happened every year at kilauea since 1983 I think that is a pretty insane demonstration of how much energy is involved with hawaiian eruptions

        • Just sticking my 2 cents in here for reference.

          I’ve used and hyped the Mastin et al equations in estimating Dense Rock Equivalent (DRE) emission from explosive eruptions. At their core, both the Mastin and the earlier Sparks work is ultimately based on the energy release rate of the vent, represented as an equivalent mass flow rate.

          I don’t have a clear answer as to what the assumed temperature of the ejecta is, but a value of 900°C (1173.15K) shows up a couple of times for comparison to the various eruptive columns used in the research.

          And a caution directly from the abstract; “H versus Ṁ yields an uncertainty within the 50% confidence interval of plus or minus a factor of four in eruption rate for a given plume height.

          Hopefully this helps those of you juggling numbers.

          Sorry, I don’t have a clean link to the original paper, just to an erratum. The original paper is titled; A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions Mastin et al, Journal of Volcanology and Geothermal Research (2009).

          The Erratum is here.

          https://www.sciencedirect.com/science/article/pii/S0377027309000146

        • …and a side note, mostly musing on my part.

          If one were to attempt to calculate energy release based on the thermal energy in on m³ of DRE, you should probably approach it as a dynamic quantity… in other words, the temperature over ambient conditions at the surface. In Mastin et al, they treat the 900°C plume effects vs a standard dry atmosphere. (United States Committee on Extension to the Standard Atmosphere, 1976)

        • In regards to my earlier rude intrusion about Kelvin and Celsius, it goes a long way towards our rumination being taken seriously if we speak the same language as those we are trying to influence. I was not trying to denigrate any of our commenters. Your musings are a class act, quite informative and well thought out.

    • Oh, something else I wanted to add, but not directly related to volcanoes but still relating to something I have wondered for a long time.
      When the tsar bomba was tested there were plans by both the US and USSR to make a 10,000 megaton hydrogen bomb. Many documentaries and sources talk about really big volcanoes in the amount of nukes they are equivalent to, but even the biggest Holocene eruptions would be dwarfed by a 1 gigaton bomb. For all purposes a bomb that big is basically a supervolcano in a box…
      If that worked they had a 10 gigaton bomb design too… That would be the equivalent of the eruption that created the fish canyon tuff, the biggest single volcanic eruption on earth since the K/Pg boundary… All of that energy released in an instant…
      Of course these were never made because they would more likely just blow a hole in the atmosphere and radiate into space instead of spreading at ground level (and they would cost a literal fortune), but they are completely possible, and that is a really scary thought…

      • “supervolcano in a box” nice analogy… though spooky.

        Now imagine if someone came up with a nuclear equivalent to a shaped charge where the principle blast focus is horizontal rather than omni-directional…

        • Yeah I was trying to think of a more intelligent sounding metaphor but sometimes being plain and simple is the best way of saying something 😉

        • It’s a fine metaphor, I like it. Cute and scary at the same time. 😀

        • I’m pretty sure a shaped nuclear explosion has been thought up before, but it might be impossible to do in practice because physical materials probably can’t respond quickly enough to react in the way they are needed. What has been conceived that is sort of the same thing is a gigawatt gamma ray laser powered by a small nuclear explosion behind a laser crystal…

          • Not my field (obviously) but I think a toroidal shaped detonation structure might do it. The trick would be in getting the thing to go critical in a synchronous fashion with an equal yield along it’s entire radius. Doable, but it would take some complicated circuitry. Based on the Wikipedia article about the topic, things get complicated fast when you start dealing with tampers, ablation pressure and gamma ray lensing systems to drive a coordinated fusion reaction. I for one, am really really glad it’s not an easy engineering task.

            And that is not even considering that the focal point of the energy release might be along the torus axis… defeating the entire effort of even trying it. (probably analogous to a stellar event energy release being along the rotational axis… but with different physics driving the show.) {Which I think might be due to rotational energy… but I don’t actually know.}

            Ref; “Not my field” → I specifically avoided picking the Nuclear Power specialties when it came time for AEF classification. I had two goals. 1) To not be on a Sub, and 2) Not be in a “glow in the dark” rating. Yeah, I was a chicken shit, but it fits with my “Don’t be there” philosophy. In my experience, bad stuff happens to me. The less I am around potentially lethal stuff, the higher the likelihood that I will not encounter a lethal situation. I know and respect my luck. As Clint Eastwood stated in one of his movies… “A man’s gotta know his limitations.”

    • ok… my name’s motsfo and i’m an explosion quake addict. (small voices around almost empty room= ‘hello, motsfo’)

  15. Now, some of the things that I REALLY like about volcanocafe.

    WE are not experts in the field. In fact in many regards, we are far from experts. However, many of our visitors and commenters ARE experts in some field. We range from pilots to astrophysicists, botanists and IT professionals. Not being experts is our strong point. We are free to openly discuss ideas and possibilities that may not fully comply with accepted ideas of volcanology. We strive to keep our discussions within the realm of scientific possibility, but we are not limited to accepted “dogma.” In this manner, anyone visiting our small corner of the Net, be they professional volcanologists or just training in that field, can be exposed to (generally) sound reasoning about the subject. This may plant an idea or seed an idea that they can later use and explore in further research. This is also why we try to tamp down any moon-bat chatter that comes along. If it doesn’t pass the sniff test to us, there is a pretty good chance that it won’t fly on it’s own merit.

    Essentially, we are crowd sourcing ideas that may be picked up to further volcanological research.

    • Having thrown that out there, here are a couple of books that you may find in a library near you.

      An Introduction to Seismology, Earthquakes and Earth Structure 1st Edition” by Stein and Wysession. It will illustrate why I rank picking seismic wave-forms as half science and half nuanced art. (It’s not just getting the waveform correct, it also involves knowing the geological settings for the region of the quake before you can get a decent localization on the quake and it’s size.) ← This is why they occasionally look much different or move after analysis. Automatic detection just gets you into the ball-park.

      Another really good starting reference is “Global Tectonics 3rd ed” by Keary(deceased), Klepeis, and Vine.

      That second book has a really good run-down about the Galapagos block and why volcanism there might be a bit on the prolific side. (Hint; The Galapagos block is rotating in place between the larger crust segments)

    • More about seismic waveforms. All of the strata between the hypocenter (3D version of an epicenter) and the seismic station have an effect on what the waveform will look like when it is detected. Some strata have faster transit times, other strata have slower transit times. The “rules” on how to interpret the seismic signals vary from station to station and much of it is determined with just how well a seismologist knows the structures in the area where they work.

      It is not unreasonable for a less experienced seismologist to do a “human” interpretation of the data and have it over-turned by a more seasoned seismologist once it gets reviewed. Personally, I imagine that this happens quite a bit, but we don’t generally get to see any of the conflicting reports. It’s a matter of quality control at the reporting facility. People being what they are, I can easily see a conflicting report slipping out occasionally. IMO deals with this by assigning a confidence factor to their quake reports. Dunno how USGS deals with it. Do remember however, that many research papers done in Iceland rely on reinterpreted seismic data, so even though they have an established method for weeding out dubious interpretations, there is still room for improvement.

    • True, also what makes it an interesting read.
      My background is molecular biology. Some of you are engineers.

  16. I think the still most reliable indicator of how large is an eruption (explosive or effusive) is actually the volume of magma erupted per time.
    Of course one can compare volumes of erupted magma, but a much more accurate picture is to compare the rate of such erupted volume per time.

    The 16km3 Laki was obviously our very big reference eruption (that happened over 8 months, giving a figure of 2km3/month). Holuhraun erupted 2km3 over 6 months (this is a far smaller rate of 0.3km3/month, about 10 times less).

    Hawaii lower Puna erupted 0.5km3 in 2 months. This is about 0.25km3/month, which a rate almost similar to Holuhraun, albeit smaller, especially if considering that Holuhraun also started stronger in the beginning.

    Kilauea Puu Oo erupted 2.7km3 in 35 years. That´s a meager 0.08km3/month but nonetheless impressive because it was sustained over more than 3 decades!

    Grimsvotn erupted 0.8km3 magma but just in 3 days! That is about 8km3/month. It´s 4x stronger than Laki (although Laki probably started with a similar brutal rate, probably erupting 1km3 in the first few days). On its own Grimsvotn is much stronger than Holuhraun or Kilauea. But of course, this pales when compared to a Pinatubo, a Krakatoa or a Tambora.

    Pinatubo erupted 10km3 is just a couple of days. That could equate to a rate of 100km3/month, far stronger than Grimsvotn.
    Tambora did 40km3 in just 6 days. That´s about 200km3 or twice the rate of Pinatubo. But because it happened longer (and erupting also more volume), it impacted the climate much more severely.

    Krakatoa was probably the strongest beast. It erupted 20km3 (about half of Tambora) but that was only done in less than 24 hours, therefore with a rate of 600km3/month, which is 3x more than Tambora or 6x a Pinatubo.

    Now the surprise… Novarupta eruption in 1912 and Oraefajokull eruption in 1362 make up for the other two big beasts:

    I will summarize:
    1- Krakatoa 600km3/month, done in just 24 hours
    2- Tambora 200km3/month, done in 6 days
    3- Novarupta 1912 eruption, 180km3/month (15km3 in 2.5 days)
    4- Oraefajokull 1362 eruption, 120km3/month (2km3 in just 12 hours!)
    5- Pinatubo 100km3/month, done in 3 days
    6- Grimsvotn 2011 8km3/month (done in 3 days)
    7- Laki 2km3/month but sustained over 8 months!
    8- Holuhraun 0.3km3/month, sustained over 6 months
    9- Lower Puna Hawaii 0.2km3/month, sustained over 2months and ongoing

    It´s possible that Huaynaputina in 1600 erupted about 30km3 in just a day or two, therefore being as strong as (or stronger) than Krakatoa.

    Reading a bit about these big eruptions, it becomes clear that almost all of them occur just within a day or two. They are basically huge explosions happening suddenly, blasting the entire volcano upwards in a few hours.

    • Now THIS is the sort of idea I was referring to several comments back!

      Based on Irpsit’s list, an average eruption is about 114.5 km³/mo, or 3.8 km³/day. The start of true black swan territory is anything above about 23.39 km³/day. (3SD above the average) Not likely, but still a non-zero probability. (Krakatoa came very close at 20 km³/day… but no one even thought that was possible so it qualifies as a swan.)

      Side note: LLN says that the more tests you have for a specific condition to exist, the more likely it is you will eventually find it.

      In our case, each “test” is the passing of a day. Basing our time as the holocene, we’ve had about 4,197,500 “tests” for something huge. (which really isn’t fair, we haven’t really existed as we are now for that long.) → 1,886,320 tests since the start of the Early Dynastic Period in Egypt. (≈3150 BCE) {Basically when someone would have probably scribbled it down on something}

      I could just see it now. “3rd year of (pick a ruler).. HOLY @#$@$!!!,” or, just “Akk!”

      • A different topic, but still a black swan in the making. And again it relates to Oraefajokull in Iceland. The IMO warns of a rockslide in one outlet glacier of Oraejajokull. Apparently unrelated to the volcanic activity in the volcano because the fractures predate the current unrest.

        http://en.vedur.is/about-imo/news/bigimg/3671?ListID=0

        Such a rockslide could amount to 0.06km3 of rock sliding towards the lowlands, where the tourist center of Skaftafell is located. A true black swan is an eruption of Oraefajokull with resulting large glacial flood that triggers and combines with that rockslide.

        The glaciers there are as steep as physically possible. Quite impressive views.

        • Don’t forget that the first requirement of a swan is that is assumed to be nigh impossible for it to happen.

          … but, that also begs the question; Is it a Swan if someone other than the victims expected it to happen or saw the possibility? From what I understand, Kiyoo Mogi forsaw the possibility of a quake as large as the 2011 Tōhoku event but no one of any significance listened to him. {Yeah I know, it sounds like a standard SciFi plot}

          I wasn’t party to the coversations nor am I Mogi, but in my opinion, he was well placed to see the coming danger. Much of his work was centered on what surface deformation could tell him and he was likely deeply familiar with the data from Japan’s installed GPS network.

          As Albert noted, the coastal tsunami defenses were not designed based on probabilistic data, but on what the largest known tsunami in the Pacific basin was. That still doesn’t disqualify it as a Black Swan. In post analysis, my guess is that as installed, they were prepared for an 85% deviation from an average Pacific basin tsunami. What they got was far above that. Had they used probabilistic methods and designed it to handle a 95% excursion, it still would have been very expensive to design and build such a large mitigation structure. (and yes, the cost of dealing with what finally happened would have made the investment worth it… but, nobody saw it coming or even considered it feasible… Except for Mogi.)

        • That’s the same Mogi that gave us the “Mogi Model”… a way of estimating magma inflow to a volcanic system based on ground deformation. Though rather simple in assuming a spherical chamber, it has proven to be quite accurate in rough guessing what’s going on.

    • Oh I know the eruption rate of kilauea is not that high compared to a lot of other places, but my calculation was for the energy involved in the eruptions, not the volume.
      Kilauea could theoretically erupt a VEI 5 every year with the amount of energy it emitted in an average year during pu’u o’o. The current eruption has a thermal energy equivalent to a VEI 6 eruption. Kilauea also currently has a supply rate from depth of about 0.15 km3 per year, which means an eruption as big as the one now could theoretically happen every 3 years. I don’t think any of those big volcanoes you mentioned would be capable of an equivalent VEI 6 every 3 years… In fact at pinatubo it is about once every 500 to 1000 years. Based on the behaviour of its neighbors it will probably take well over 20,000 years for tambora to have another chance of going VEI 7.
      It is sort of equivalent to lighting a bowl of petrol on fire and a pile of gunpowder. The petrol has more potential energy (about 5 times more when stoichiometric oxygen is included) but the gunpowder releases much more energy in a set time because it can burn much quicker. The petrol is kilauea while the gunpowder is pinatubo or krakatoa.
      The other thing is that the volume of ash eruptions is often an assumed average because ash can easily move after the eruption ends and in a mountainous environment it can be easy to majorly underestimate or overestimate the volume. Ash is also much less dense than solid basalt, so the dense rock equivalent of most of those explosive eruptions would probably be around or under 10 km3 by the numbers you gave, still very big but now comparable the bigger effusive eruptions in a more direct way.

      When you do the maths this way, it gives a much more impressive view of effusive eruptions. It is true that in the moment of eruption pinatubo released much more energy than kilauea in the contemporary time period that both were simultaneously erupting, however it will take pinatubo hundreds of years at least to prepare for another eruption that big, while kilauea had already emitted more than double the total energy of mt pinatubos eruption by the end of the decade…

      This is the answer to solving the inherent bias of the VEI scale, looking at total energy of the eruption. Suddenly Hawaii doesn’t seem so tiny after all…

      • One thing that might be useful, is to consider the energy requirements to pulverize rock and add that to the equation. When Kelud went up, I used a rock milling formula to calculate a rough estimate of the energy release, I came out pretty close to Carl’s estimation based on isopleth data. Another pretty close value was obtained via how far away the blast was heard. If I remember correctly, my value was in the 6 to 8 megaton range.

        It also fit into the correct range based on plume height.

        • How much dacite can you pulverise with 1.32 x 10^18 joules? That is the thermal energy of the current kilauea eruption based on the last USGS issued volume of 0.45 km3.

          Or how about with
          5 x 10^18
          (holuhraun thermal energy)

          Or with 4.1 x 10^19
          (skaftar fires minus ash, total thermal energy)

        • To effectively use a milling formula, you need the original rock mass (assumed to be one humongous block) and the size of the resulting fragments. Then you toss in a milling efficiency value and trudge through the calculations. For Kelud, I used the size of the extruding plug as a starting point. (The one that displaced the lake) Even though I came reasonably close to other estimates, there was a whole lot of room for error in my estimates.

          I suppose that it might be possible to find the quantity of distal ash and work backwards through the formula to get an approximate size for the original “rock” mass. Though in reality, all you would be doing is attempting to validate the DRE estimates. However, it might be useful in differentiating flood basalt flow vs ejecta volume.

    • This is a very logical approach, and, in my opinion, the right one when looking at the strength of an Eruption. However….this should only include DRE numbers since this would be fairer for effusive eruptions.
      These are a bit mixed up here, I think. Pinatubo was about 10,3km3 tephra and roundabout 5km3 DRE. The 40km3 for Tambora is the DRE. The 20km3 for Krakatoa is tephra volume, corresponds to 10.3km3 DRE. So Krakatoa was a quarter of the Tambora eruption and about twice as big as Pinatubo.
      I think the 0.8km3 for Grimsvotn is also tephra volume (borderline VEI 5), not DRE.

      • Yeah I realised the numbers in my original comment would actually be tephra volumes not DRE equivalents, but still there is no comparison. Kilaueas thermal energy output since pu’u o’o started was equivalent to 18 pinatubos, roughly one every 2 years… Or 9 krakatoas… Or just over 1 tambora….. The current eruption is equivalent to at least 4 years of what pu’u o’o was doing, which makes the current eruption equivalent to 1/9 of the volume of pu’u o’o, and this would be the same thermal energy as krakatoa.
        It is quite likely to be at least 50% bigger by the end too, especially if it taps into and drains the roughly 0.4 km3 combined magma chambers under the napau and makaopuhi areas as per thedustdevils idea (this hasn’t really happened yet, there has been relatively little deflation on the east rift). If that happens then the eruption will cause collapses in those areas and may continue for significantly longer than the summit collapse, possibly even long enough for the summit to reactivate and erupt again, although that is speculation.
        It is one thing to look at this eruption as the volume equivalent of a large VEI 4, but it is another thing entirely when you realise this event is already as potentially energetic as a mid scale VEI 6 like krakatoa and shows no signs of actually stopping soon…

        This would also still leave the Icelandic flood lavas as the most powerful volcanic eruptions in the Holocene. The thermal energy of the skaftar fires eruption is equivalent to an eruption of 408 km3 of tephra. I don’t know what that is in DRE but I am not convinced any eruption as big as whatever that number is has happened in the last 13000 years. The thorsja eruption was about twice the volume of the skaftar fires event and I know for a fact that no eruption with a tephra volume of ~840 km3 has happened since the VEI 8 oruanui eruption of taupo 22,500 years ago. The south Iceland volcanic zone is the most powerful volcanic field on the entire planet, it would be like having a VEI 8 happen every 1000 years or less.

        I will admit I actually wasn’t expecting to see numbers as big as I did for any of these eruptions. I was expecting something maybe an order of magnitude lower…
        I definitely didn’t expect kilauea to be such a behemoth of a volcano either, at least not one that is capable of a potential VEI 6 every 2 years. I’l probably never find any other single volcano impressive ever again now…

  17. I have a question about the last M5.3 quake under the soutwest rim of Kilauea. USGS has set it on -0.4 km now. I have been watching the earthquake happening on the webcam a dozen times now.
    First the webcam starts to tremble, a split second the trembling stops, after that the cam gets a dash uplift
    (9.20 Hawaian local time).

    What does happen? Is it one explosion that gets segmented by travelling through 3 kms of rock? The webcam is about 3km away from the spot were the quake originates. Or is the event segmented itself? Something happening that shakes and triggering the explosion? The quake is clipped on seismographs, so no further info there.

    • I can’t answer you, but this is the sort of thing I was referring to in my 20:45 comment above. It boils down to how well you know the the underlying structure of the ground in the area between the event and the seismo. Something HVO has been studying for years (before they got run off by the increasing hazard) {Still a wise move on their part}

    • And there ‘seems’ to be a pause in the fumes just before the earthquake (which was more easily seen earlier on). and how’s that for ending in a proposition. Please think about the observations that a viewer makes are filtered through a device which relies on transmission time instead of being on site. Although fast, it might be a little like the ‘cave wall’ effect of what’s his face…or dead cats etc. Best! motsfo

      I watch because it’s fun to observe; I live with lots of earthquakes and when they happen the spike in adrenaline rush makes it impossible to observe minute details. (and the screaming is soooo distracting) and because one is moving with the objects, it’s impossible to determine how much the movement is…. Anyway I’m glad the tree is in the picture; fun to watch it jump.

      • OK – my apologies but a wee bit OT. Motsfo, you have reeled me in. Very long-time reader, first time commenter (be gentle, admins). I know you’re in AK, and that has always been my target state (I’m in N. Illinois) because eventually I want to finish my schooling at UAF/GI… And it’s so tectonically active, and beautiful, and I love salmon, etc.

        I blew beer out my nose when I read your screaming comment, because I think the same thing. OMG – that was perfect. The first earthquake I ever felt was while visiting family in SoCal in the summer of 96, and there was like a 4.0 nearby; had a good shake mid-morning for literally 2.5 seconds. The fascinating silence immediately after was shortly broken by some dogs barking and some car alarms. [That WHOLE experience was transformational peronally].

        Then from the next room my future sister-in-law lets rip with a scream. I politely advised her with an outburst of laughter that 1) she was about 15 seconds late to the party, 2) it wasn’t that bad from the perspective of a quake virgin, and, especially 3) she has lived here her entire life. That episode didn’t leave our family gathering until the newlyweds left for their honeymoon…

        So cheers to you for rekindling that story so that I may share it.

        Admins are happy to be gentle. Welcome! As usual, a first comment requires approval (sadly we do get spammed), which we are very happy to do with apologies for the delay! – Admin

        • Reminds me of my first quake. I was standing in front of the apartment building and could sense the entire framework of the structure wiggling back and forth and could hear the creaking. That was when they discovered that there was a “new” fault-line running down the middle of San Diego bay. (part of the Elsinore fault system)

        • motsfo checks off another box=== make someone spew beer out their nose. check

    • Heloooo Nurse!

      Just look at that inflating dike! It seems the maximal uplift area along the dike is where the fissures appeared.

      BTW, that “Hello nurse” colloquialism was resurrected in the “Animaniacs” cartoons.

      • That picture shows how the east rift drained uprift of the eruption, two parts of it (one presumably being pu’u o’o and the other makaopuhi) actually deflated as much as the summit did in that early stage.
        It is also interesting how the part where the deflation transitions to inflation is where the highway is, possibly explaining why an eruption hasn’t happened there despite a potential vent existing. Pu’u 8 (I’m calling it that now, it definitely isn’t a fissure anymore) is also right above the centre of the inflation so maybe it isn’t surprising it is the main vent.

        From the looks of this pu’u o’o and makaopuhi are areas where pit craters could form in the near future.

        • Quick update,
          We we’re in volcano Hi today about an bour before the larger quake happened. We left because I was driving and my earthquake checker told me we had no activity in the lalt 20 or something min.. I figured we had missed the quake while driving up (knew that it had not occurred while we were in Hilo) so we spent a few dollars in Volcano and when back down. We we’re were able to see a good steam discharge while driving to see if the usgs had opened anything up there, the sink hole had been repaired.
          We are in a Airbnb in Hawaiian beaches subdivision. The glow is out our back window. We were able to ride down government Beach road to the checkpoint but there was nothing to see, although it is a very beautiful ride. We got into Nanawale (resident access only) estates and when to “A” road but only got to see the glow “better” dead quite there. We drove over the metal plates on 130 and investigated the area down by Issac Hale park where we meet another road block (but another beautiful ride!).

          Other than the steam on 130 (my 10 year old daughter was terrified when she learned what was causing that) and the “glow”, and the helicopters, I would not recommend anybody spending a dime to come look. My biggest take from the event is that the fissue is creating it’s own weather here locally. Other than the weather you can’t see or hear anything. Sit at the PC or phone and watch from there.

          Heading back to Kona in the am.

          Mac

          • still glad You went …. those ”5’s” are nothing to sneeze at and the 10 year old is probably better to have missed it. Earthquakes are hard on bad backs(ask me how i know). Enjoy the rest of the time. Best!motsfo and think of this… You added to the community with funds so needed.

          • Okay… I’m asking. My only concept of how it could be so is via the Rayleigh waves in the stronger quakes… or you were standing on the epicenter. A mag 5.0 should only be about 12.1 to 13.7 %g at ranges less than 8 km or so. (12.3 cm/s acceleration)

        • The main deflation in the east rift seems to be concentrated around a thin area east of Napau, my interpretation is that the deflation corresponds to dikes that were recently emplaced during the Pu’u’o’o eruption. I think the most likely places for pit craters to form are Puhimahu, Pauahi-Hiiaka and Alae-Makaopuhi (this one would probably be the biggest one), this based on how intrusive earthquake swarms have behaved and are also the location of craters that collapsed probably during the 1790 eruption, so if this is really where magma reservoirs are awaiting things would not have changed much since then. Pu’u’o’o has been suggested as a place where reservoirs may exist, but I have some problems with this, from my observations past pit craters have formed in intersections of Koae faults with the East Rift and that doesnt happen downrift from Napau or Makaopuhi. At Hiiaka for example magma can intrude into Koae to the west and to the east and can also go downrift to the south and uprift to the northwest, as seen during the Mauna Ulu eruption (things seem to have been much more boring since 1983). So I am really interested in seeing if craters form at Pu’u’o’o if pit craters collapses take place in the ERZ (which seems likely to happen when this eruption has already outdone in terms of volume 1790 and probably any other LERZ eruption excludind the shields at the Heiheiahulu area? since at least 490 BP but maybe even since earlier).

      • It also shows that everything seems to be localizing to the summit now, and the deflation radius is smaller and basically the size of the new collapse.

  18. This just in from HVO:

    “Early this afternoon observers reported multiple overflows occurring along both sides of the main lava channel, in an area extending from near the “Y” intersection at Pohoiki Road eastwards to an area just west of Kapoho Crater. Overflows on the upper part of the channel did not extend beyond areas previously covered in lava. Overflows further down the channel have reached beyond the flow field, including one flow lobe that is moving northeast from the main channel towards Cinder Rd.

    Residents are urged to heed warnings and notices from Hawaii County Civil Defense.

    Based on information from ground observers and morning and afternoon overflights, the lower part of the main lava channel has undergone significant reorganization. In particular, the channel that had been open near Four Corners is now mostly crusted over, and plumes from ocean entry are significantly reduced. It is likely this is due to a blockage that formed in the early morning in the main channel upstream of Kapoho Crater. Flow volumes coming out of Fissure 8 remain significant, and it is possible that changes in flow channels will continue to occur in the coming days.”

    • Cinder road runs to the other side of the 1960 flow. The area to where they proposed to relocate Kapoho.

    • The channel near kapoho crater.

      I think the lava will probably keep leaking into the ocean for a while though, I wouldnt be surprised if the lava is at least 30 meters thick in that area and the middle of it is probably all molten still.

      • It is possible that the lava river will completely disintegrate going further upslope now. It is already known that lava tubes tend to self destruct after a while (about a year for the kamokuna lava tube last year) probably because they overheat the surrounding areas and collapse, and it appears as though lava channels/rivers will do the same. Mauna loa 1984 took about 2 weeks, and I think it took about a month for holuhraun. Given that the volume hasnt actyally decreased though a lot more places to the north and east are at risk, especially the area down from where the big lava lake is just before the river starts.

        • And it looks like I was right, several live updates as well as USGS and Civil Defence in the last hour saying one half of the braided channel has completely clogged and the volume is causing major overflows of the other side…
          The eruption rate at pu’u 8 seems to have surged slightly too in addition to all of this. It is fairly likely that there will be multiple large flows going east and maybe north in the next few days, probably with a major increase in the surface area of the flow too.

          • Observations from your roving Volcano cafe field agent.

            There is a very large steam event observed away from the vent. With all of the steam, this area is more reflective than the main vent. We took a trip down to goverment beach beach road and noticed a utility truck from the fire Dept and several police headed to the check point down there. (One road North of cinder, think papaya farms)

            We then went down 130 to the steel plates and noticed steam a little heavier than our previous 6 trips over the plates. We also saw steam comming out of cracks that were not covered, had not seen that the other times. Most of the steam had been comming from the sides of the roads before.

            I guess if the lava is hitting fresh ground that would explain the steam event.

            When we left the house we saw the steam event occuring in the direction of the river looking down our street,
            Manini St. In Hawaiian beaches

        • I imagine that something like the “Old River Control Structure” on the Mississippi would never be practical. (the one in Louisiana keeps the Mississippi River from switching to the Atchafalaya River, which is it’s natural mode when the current channel is less able to handle the flow. Many times during the Holocene the Atchafalaya was the dominant path. (Don’t worry, eventually it WILL happen again.)

  19. https://www.facebook.com/harry.durgin.1/posts/10156417405204242

    This is a little story and detailed description of when the activity really started going big, on the first day of new lava erupting at pu’u o’o. This was around the time someone got hit by the lava bomb.
    It seems like USGS might have been underestimating the size of the fissure 17 fountain, it was probably at least 100 meters tall, and some of the explosions next to it were several times higher. Of course this entire area is now inactive but it is interesting to see where it all began.

    • It does not show it on the map but railroad Rd is closed (evacuation route) from Nanawale estates toward the river

  20. answering Lurk way up thread: re: shaking at the rate or amplitude that i have seen from Volcano cams in houses and the cam set on the HVO ledge showing tree violently shaking and the fact that Mac said he was in the town Volcano and if You have a compromised spine with ruptured disks any bouncing around is pretty painful. Think of a rutted road with no shocks and You are bounced around with no limits as to direction or force so that You cannot brace in anticipation. and this motion can be in all directions and is as strong as the earth under You. i’m impressed with all the math but where in the equation is old injured and weak? Most people around me are not effected and i don’t know about Mac’s condition but i for one dread the back pain the worst when the shaking starts here. Hey, HI or did i misread the question?? if it wasn’t to me then…… nevermind… in my best roseanna roseanna danna … 🙂

    • Much less activity now from the house. On a local news channel it was the 4th news story tonight.

    • You would pick Roseanna Roseanna Danna. I dated a girl with a similar hair style once a long time ago. (and no, not the same diction, she could actually speak normally) RIP Gilda Radner (the actress who did that character). Cute and funny. Millions of laughs.

      I appreciate the response, and concur with the stress effects on an ailing spine. Fortunately I haven’t gotten that far along. I can still fall down with some semblance of grace. (Fell off a {stationary} truck a couple of years ago and managed to grab a hand-hold on the way down just in time to swing out of the way of the copier that would have landed on top of me.)

  21. Because I think I have made my point about why kilauea is the best volcano 😉 I have decided to actually make a post about something else for a change… 🙂

    Because I live in Australia where there are no currently imminent eruptions on the way, I decided to look at some of the older volcanoes. One of the more obvious and biggest ones is mt warning, which is the central plug of the massive tweed volcano, one of the biggest still standing volcanoes in the southern hemisphere even though it is 23 million years old.
    On the wikipedia page it mentioned that the initial stages were extensive flows of basaltic lava that covered a huge area about 100 km across, and that paleosoil and sedimentary rock are sometimes found between the flows which indicates significant time between eruptions during this period. Afterwards is started erupting more silicic rocks from its central vent area, which are very hard and have resisted erosion in a lot of places. Basalt erupted again on top of this rhyolite and slowly declined before the volcano went extinct.

    It is this first stage of activity that I noticed, because there is a very strong similarity between the eruptions then and the currently active mcbride volcanic field a lot further north. Mcbride is extremely flat so it isn’t really a shield volcano as such, but there is a general high point in the middle and the slope of the field seems to largely radiate from a central point. The central point is today near the location of undara crater, the origin of one of the most extensive well preserved lava flows on earth. Eruptions happen about every 10,000 years here, the last one was kinrara volcano and it was recently studied in detail and found to be 7000 years old, making mcbride the second holocene volcano on the Australian mainland, and the next eruption will very likely take place in the next 5000 years. Studies at the same time as that appear to indicate there have been no significant positive deviations from that 10,000 year gap in at least 2 million years, with the eruption frequency gradually increasing over that time, although as the undara field is relatively young and covers half of the entire thing there could be a lot more hidden vents.

    I have thought about it a bit over the last few days since I commented on it above, and I think the mcbride field could be in the initial stages of the formation of a large polygenetic central volcano, which would be the first to form in Australia since mt canabolas 13 million years ago. Mcbride isn’t near a known hotspot but whatever is feeding it is very robust and doesn’t seem to be dependent on deep mantle sources as eruptions have happened in the same area for over 40 million years but especially have picked up in the past 2 million years. It is possible that the area is being warped slightly due to continental collision further north where Papua is colliding with island arcs in the pacific. This would produce a similar affect as what Carl described in his Volcanoes of Norway post a few months ago, although not quite on that scale.

    I have not found any evidence that mcbride has a magma chamber within the crust, but there are very few studies done on it beyond the size of the lava flows there so it is actually very possible that it does have a magma chamber, possibly formed during the at least 150 year long undara eruption 190,000 years ago and kept alive by nearby smaller eruptions since then. Eventually the magma supply from depth will increase as a more established and open conduit forms and allows more extensive melting, and as the volume increases some more silicic rocks erupt and build a noticeable edifice, although basaltic vents will likely erupt around it still. All of that is hypothetical but some similar volcanoes, like payun matru in Argentina, have magma chambers and silicic volcanism alongside long basalt flows, and have even formed large calderas, so this could be what this area is destined to become in the future.

    It is pretty cool to think that this volcanic field could be on the verge of becoming a true central volcano (in geological time at least). The area is quite high up already so if it gets to a fairly standard height of 2.5 km tall above its base then it would be a 3.5 km tall mountain, maybe the first time one of those has existed in Australia for a very long time.

    Again, a lot of this is not actually known (yet) but it is fun to speculate.

  22. https://www.youtube.com/watch?v=M9lVbLyySRQ

    New eruption update conference call. They talk about the lava flow behaviour around Kapoho, about the perpetual pyrocumulus cloud and they also say that activity at fissure 22 continues in a strombolian way and that it could be due to interaction of the magma with groundwater. I find this a little unsettling, the craters of Puulena, Pawai and Kahuwai are close to where 22 is and formed in explosions probably triggered by contact of magma with groundwater that deposited an up to 10 m thick tuff. I have also said more than once how the craters could have formed during the Puu Kaliu eruption (that we have used here as an analogue to the current one) though other eruptions like the 490 BP flow or the picrite eruption that sits on top of Puu Kaliu could also have caused the event. All people have left the fissure 22 area already and explosion would only have are very local impact so no one should be in danger in case of an unlikely but possible phreatomagmatic event there.

      • But like how close? I was considering that the part of Leilani not buried was the closest, I dont think the Puulena tuff reached very far not as far as the distance between fissure 22 and what is left of Leilani but I dont have a good description of that event either, I have tried to find information about it but there doesnt seem to be much or at least not accesible.
        Phreatomagmatic eruptions seem to be very unusual in the middle and upper part of the LERZ, unusual enough for the Puulena tuff to be the only one exposed, but if water-magma interaction is happening right now at fissure 22 maybe there is risk for a more violent interaction that even if there is a very small chance of happening it should be considered.

        It is more common for phreatomagmatic activity to occur at the beginning of the eruption and not in the middle or nearing the end. I am not sure of what would be the mechanisms that could cause this to happen so late, would open cracks, magma emplaced during the first phases of the eruption or maybe new magma arriving combined with the semi-permanent rain under fissure 8 pyrocumulus cloud be enough to trigger phreatomagmatic explosions?

        The malama craters may look large but that is not because of the removal of materials by explosive events but it seems to have been due to collapse of the area after the eruption. I think the deposits were very localized around the craters but I can not say that for sure as I havent been able to find any good descriptions about it, the tuff reaches a thickness of 10 m but I think that must be right at the rim of the craters.

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