Chile-Cerro Negro: Is this the one?

There are so many volcanoes right now that have the size and history to produce a massive eruption but only one volcano has me worried for the imminent future and you’ve heard it’s name before, Chiles-Cerro Negro. As of late Chile-Cerro Negro has been having a massive swarm with accelerating deformation which has caught some attention from our community and as the volcanoes representative it is my duty to give you an update on the volcano’s current situation. I have already wrote too many articles of subpar quality concerning this volcano and I don’t really want you to go back and read those. But I also don’t want to retrace old ground and this article will be all you need to understand this volcano’s current situation, and what is so concerning about this volcano.

Located on the border of Columbia and Ecuador, this system consists of the 2 stratovolcanoes and 1 caldera at the minimum and it has been dormant for over 12,000 years. Something changed in 2013 when an intrusion began, starting a massive swarm and for almost 10 years this volcano has been under constant changes which leads me to believe that this volcano has some scary potential. It may seem a bit disingenuous, after all this volcano at a glance seems to be your typical stratovolcano couplet but this couldn’t be further from the truth.

There are 2 calderas and several other volcanic features near the volcano that are all uplifting or under seismic stress. That is not indicative of modest potential. 20 km wide area was under uplift surrounded by a ring of subsidence, something that occurs at caldera volcanoes but not really at stratovolcanoes. On top of that, regional faults have been under stress for over 8 years. This never sounded like your typical volcanic unrest but now? Now it’s clear as day that something is very wrong with our black hill.

The red flags began in 2018 when the second swarm began. Despite being reasonably large, there was no official confirmed cause but it had been postulated that this was the result of magma chamber pressurizing. 200,000+ quakes don’t just happen for no reason and I was confused to see an underwhelming response by the geological agencies. More than 4 volcanoes under unrest at once? Large inflation? Stressing regional faults? Dormant for years? This all sounds pretty interesting!

But after 2020, the activity at Chiles-Cerro Negro fell of a cliff, deformation stabilized, quakes became scarce. It got to a point that I started to wonder if the volcano was about to back to dormancy but I noticed while Chiles-Cerro Negro activity was going down, Cumbal’s was going up. Now I don’t believe Cumbal is part of the same magmatic system but these two volcanoes share the same tectonic system and the hydrothermal activity at Cumbal is influenced by the tectonic stress at Chiles-Cerro Negro. A seismic uptick at Cumbal gave me suspicion that everything hadn’t returned to normal and I was right.

Starting in April, LP earthquakes started to take place at our Black hill with a SHARP rise in deformation. Let me just say that if the instruments are working properly then this is the most incredible deformation I have ever seen on an Inclinometer. Since the swarm began there has been a shift of over a million microradians at two instruments and uplift has rose to over 10 cm/year at one station with faster uplift likely further south.

This isn’t it though, despite the scary numbers the real fear-stoker is where the LP earthquakes are taking place; in April these were taking place 30 km below the surface but now they’re taking place 1-2 km below the surface with more LP earthquakes than any other of the past swarms. The current unrest is most likely being driven by a large volume of buoyant magma, and to make matters worse, the hydrothermal system is being disrupted by this magma and there is still no surface degassing of this shallow magma which means the system is plugged.

First swarm- Magma intrusion

Second swarm- chamber pressurization

Third swarm-ascending magma

I still don’t think we’ve reached the point of no return but only a fool wouldn’t watch this volcano like a hawk. I can’t speak to how exactly big this volcano is, or if it’s going to erupt but if it does erupt, it’s going to be big. I have never seen such a coalition of so many insane numbers in one volcano and nothing points to this volcano being small or modest in size

Is this the VEI 6+ caldera-forming volcano we’ve been anticipating? We’ll see.



285 thoughts on “Chile-Cerro Negro: Is this the one?

  1. At last! Chile-Cerro Negro. Great article and thanks, Tallis!
    I’d like to say let’s hope you are wrong. But with volcanoes you can never be too cautious, as Hunga Tonga showed us all. You’ve done your research very well. I hope they will listen to you.

    • Unfortunately, The IGEPN is dragging their feet when it comes to reporting data, it’s been two weeks since they published a weekly report and 3 months since they’ve published a monthly report. They’ve only released gps data for one station when there are 5 stations. Hopefully they’re being straightforward with they’re reporting.

      • poor country maybe not enough resources? I wonder if they can ask for help monitoring things or perhaps the powers that be do not want folks to become scared or they are trying to encourage trade and investment so limiting info. The rest of the scientific world should offer assistance.

        • Well, we probably should be getting involved already to be honest. This volcano *is* marked on the USGS Volcanic Disaster Assistance Program, or VDAP. We’re already prepared to help here, at least in theory.

          • The VDAP Cerro Negro is a different volcano, in Nicaragua. VDAP is a brilliant program. The list you found is for volcanoes where they have provided assistance in the past.

  2. Scary times… Potential VEI7maybe. Potential biggest nuclear accident ever…

    Better stock up on toilet paper…

  3. Thanks Tallis! Been looking forward to this one.

    I genuinely search for news out of South America on this volcano just about daily right now. Of course none of us can divine the future here, but there’s just something about this system that “feels” major. It reminds me, a bit, of everything I’ve read about the run up of Pinatubo in 1991; identifying the monster and realizing this could be a problem. We’re not there yet in full, nothing is “imminent.” But I fully agree with you that this needs to be watched like a hawk.

    Maybe it does nothing. Maybe it burps. Maybe it has an effusive event a la the first Quizapu eruption. Or maybe it intrudes a massive plume of ash and gas into the stratosphere, and we’re looking, mouth agape, at an eruption of incredible power.

    I do wish that it decides to make its intentions clear enough that the locals can GTFO in due time.

    Thanks Tallis, this was a great summary and I appreciate getting a chance to see that data.

    • Speaking of the locals. What’s the population like in the danger zone? How many are at risk if it decides to go big?

      It’s a scary beast for sure and the signals make me uneasy. Can’t shake the bad feeling I get about this one. I would much rather go back and watch beautiful red stuff fountain from the ground than see this bad boy blow up.

      • The city of Tulcan lies about 20km east of the edifice of Volcan Chiles with about 50,000 people, and another 8km or so further east lies Ipiales with an even larger population. Cerro Negro de Mayasquer lies a few km northwest of Volcan Chiles.

        It’s going to depend on where the potential center of activity is and of course exactly how large the event becomes. Of course if we’re talking a very large VEI6 with powerful pyroclastics, it looks like a lot of people will need to evacuate the area.

        Probably why they’re hosting evacuation and eruption drills, from what I saw in local news, to better prepare for an event.

    • The volcano has some potential but don’t bet on the agencies taking this seriously. It was fun to speculate on this volcano before but now that magma is rising and is just 1-2 km below the surface, there is no excuse for the lackadaisical response. The volcano has just become one of the fastest uplifting volcanoes and the expanse of the activity is impressive. Back in 2020, the LP earthquakes were clustered in the NE portion Cerro negro and were happening at 50 km below the ground so we’re dealing with system that is over 30 km wide and 50 km deep. Someone needs to take this seriously and give some good data on this interesting system.

  4. Chile-Cerro Negro: Is this the one?

    It’s the one alright; well in terms of interest to me at least. Sounds like the perfect disaster waiting to happen…

    – Long dormancy.
    – Stale magma.
    – Large earthquake swarms that occur more frequently.
    – Large area of uplift.
    – Evidence of previous calderas from large eruptions.
    – Sizable magma chamber.
    – Near the equator, so ash has easy access to both hemispheres.

    I did see someone mention that there seems to be 2 different depths of earthquakes where the inflation is occuring and they thought that there may have been 2 magma chambers inflating. Any guesses as to how big the capacity of these chamber(s) might be?

    • I don’t know, it really depends on the systems structure and how the possible multiple chambers are connected but my guess is around 10,000 km3 of Magma. (20×30 are the systems dimensions at the minimum)

      • Note however that the volume of intruded magma can only be as large as the volume of the domed up area above it. This is because intrusion of magma requires a displacement of rock away from it to accommodate the intrusion, in dikes this displacement is horizontal, in magma chambers, sills and cone sheets the displacement is vertical, upwards.

        Here the inflating area is about 300 square kilometres. If 10,000 km3 of magma had been intruded here then it would mean a 33 km uplift of the ground, which is clearly not the case. It is hard to tell the amount of uplift without fieldwork, hard to know how much magma could have been intruded under the area. Certainly not more than 300 km3 though, or the uplift would be very obvious.

        • That doesn’t tell you how much magma there is, though, just how it has changed. The change will be a combination of new magma and reheating (and expansion) of what was already there.

          • Yes, the recent documented topography changes indicate new magma mainly.

            What I was referring to, however, is that there should be a remnant topographical uplift from all magma that has ever been intruded in that area, even the magma that is now completely solidified must have contributed to uplift. Of course characterizing such an uplift would be very difficult given the irregularities in the terrain, erosion, and deposition of volcanic materials, so it is hardly useful unless a very detailed analysis was made, documenting faulting and folding of strata, right there on the field.

            See this for a visual example:

          • Whose to say there isn’t a dome here? The dome or uplift Uturnucu was missed for years despite being over 1km high and 70 km wide due to being surrounded by regional “junk”, Calderas. lava domes, and an overall complex topographical setup made it hard to spot. With a smaller and lower dome could be missed for similar reasons here

      • I don’t know man, the primary reservoirs don’t show *that* much depth. Based on the seismic spatial distribution, i only come up with a total volume in the 1,000 km3 range. at the absolute most. at least in the main brittle crust region. there’s probably more in the deep reservoir, but.

        • And that’s just the spatial volume, not the melt volume.

        • My 10,000+ figure is for deep crustal chamber, if this volcano were to produce a caldera forming eruption the magma would come from the deep chamber. In 2020 there was a smaller swarm of LP earthquakes taking place 35-50 km below the ground with some distance from the main activity, and it should be noted that the area of the seismicity is almost always smaller than the systems total area. I do think there is some evidence that points to extensive deep chamber, the aforementioned deep LP swarms and the extensive multi-volcano deformation all support this. None can really speak on the shallow chamber since we don’t know where exactly it is to begin with, how deep or wide it is, ehich portion of the surface activity is it influencing. I didn’t include my thoughts on the systems size in this article because any number we come up with would be nothing but speculation without any significant evidence.

        • I mean, to be fair the crust is thick in this part of the world, it would not really be surprising if there is a lot of magma under any one of the volcanoes. I dont think this place is a VEI 8 progenitor, it hasnt really got that sort of grand scale of activity, it might well in the future but there is nothing that stands out about it more than its neighbors, and as far as I know calderas are not unheard of but not particularly common in this area either. Still, an eruption like Pinatubo and not that far away from a major city is concerning, and that would nto require anything that extreme really, it might even be expected as an openign stage after such a long inactivity.

          • Let’s not talk about VEI 8 eruptions, Daily Express maybe reading and we don’t need this volcano to be the next Yellowstone! But seriously, this system has already produced 2 VEI 7 eruptions. Both and Potrerillos and Chalpatan are more than 7 km wide, around the size of the Tambora caldera. The Chacana Caldera which is 50 km long and 30 km wide so there is some regional precedence for some huge eruptions and extensive Magma development beyond the low end VEI 7 range.

  5. Great article Tallis, Thanks. I remember Pinatubo, I was working for a park here in the USA the year after that eruption. Well, it rained excessively that summer, it just poured and was cool constantly. It was finally Labor day weekend, the last official holiday of summer and of course it poured rain. As I turned the park watch over to the night guard I had to drive past several cabins only to see the renters out in the pouring rain trying to play volley ball. My thought was “yeah, this was the worst summer ever folks”. So imagining another 6+ means a big weather change as it is close to the equator it could impact both hemispheres? Definitely it will be on my radar to watch out for.

    • I distinctly recall the winters of ’92-’94 in NYC which followed. Uffff!!

      • There is reason to speculate that the Super El Nino of ’97-’98 was (in part) a whiplash event following the cooldown caused by Pinatubo.
        Once the atmosphere gets sufficiently destabilized, it can take many years for a new state of equilibrium to get established.

        • I’m fascinated to see exactly how the climate forcings from HTHH will play out over the next few years.

          While it appears the injection of water vapor into the stratosphere was enormous (~10% of the normal total up there), yet the SO2 flux was rather low (roughly 1/40th of Pinatubo, depending upon the exact figures you take for either), I still believe some disruption to the normal ebb and flow of the various oscillations will play out, and exactly what that will be is very fascinating to me.

          We’re entering a third year La Nina which, though not unprecedented, is rather unusual.

          • At present, it appears that the spike in stratospheric WV is having a greenhouse effect…hence instead of volcanic cooling, we’re seeing volcanic warming…especially in the SH. Much to learn here, fer sure.
            Note that the warming is happening at a time of pre-existing accelerated Antarctica ice loss, and IMHO the cold melt water is being transported to the equator via the Peru Current which in turn is constructively interfering with the prolonged La Nina.

      • It snowed in San Francisco and there was ice on the sidewalks in the daytime. That is very unusual. Cold winter 1991-1992.

        • Yup I know. I was living there (my birthplace) at the time. The damage was extensive to landscaping and general agriculture as well.
          In the outskirts of The City proper, temps plunged into the ‘teens (F).

  6. It does look like this place will have a very different look in 10 years than it does now. Chances are that it will resume stratovolcano building, which might mean the first eruption is less of an ignimbrite and more of a stable plinian eruption with relatively low range laterally. Or it might begin effusive as seems to often be the case. But if uplift is over such a big area at some point it will break its mold and go caldera properly, which might be in the low 7 range if it really self destructs. Hunga Tonga showed that ignimbrites are incredibly fast, and seem to be that way regardless of magma composition, as it was hot crystal poor andesite, a lot like the fissure 17 lava from Kilauea in 2018.
    Im starting to think VEI is not applicable above a high 6, VEI 7s and 8 probably involve multiple collapse events of the caldera, not one that is bigger. Kilauea collapsed sequentially and every time the eruption got stronger temporarily, the same thing happened at Bardarbunga, it seems to be how calderas form all over. Taupo in 217 AD was a 6 in volume but with the power of an 8. So you get a caldera collapse that starts, and the first blast is a 6, and in bigger eruptions there are more collapses, until it cant keep going. So we could be looking at a supervolcano scale blast radius if this thing does go for a VEI 6-7 ignimbrite. It doesnt look crazy populated but no doubt it will be a disaster, Columbia already has a claim to the worst recent volcanic disaster, even though that one was human error not the volcano itself or the volcanologists, it is not a good track record…

    Excellent article Tallis 🙂

    • Insightful as always, Chad.

      Albert made it click for me the other day when he mentioned how an observer in the future would look back at Fagradalsfjall 1 & 2 as the same eruptive sequence. A year of separation is nothing.

      How many large eruptions in the past are multi-stage events that happen over a timeframe that would be quite long to a human observer? I know some we can tell with a bit of precision, while others we’re not entirely sure.

      It made me think of Saskunarvatn and how the tephra was originally thought to possibly be Iceland’s only singular VEI-7 but was then revealed to be a sequence of moderate to very large events over a few hundred years. A few hundred years is multiple human lifetimes.

      Just very interesting perspective in there if you think about it.

      • RE: “but was then revealed to be a sequence of moderate to very large events over a few hundred years. A few hundred years is multiple human lifetimes.”

        Those looking back will have the advantage of voluminous and accurate data which will eliminate a great deal of the speculation current research is often obliged to employ in their analyses.

  7. Well Tallis, you’ve piqued my curiosity. I’ve gone back in time a bit and now wonder if you have any thoughts or projections, using your Volcanic Societal Impact scale, as what the outcome might be for not only the region, but the planet as a whole, if the system uncorks?

    • Thank you! If we’re talking about the worst possible scenario for the volcano then I would say VSI 12.

    • I don’t know how it is with Icelandic moss, but ground fires can sometimes be burning below the surface through glowing combustion. I think it’s more likely that the heat is caused by the fire than the fire being caused by the heat. Remember that rock is not a good heat conductor. If the ground was so hot from fresh magma that it could set moss on fire it would probably already be erupting.

  8. GeologyHub had an interesting video about the Chiles-Cerro Negro complex some 9 days ago. He speculates that there are 2 magma chambers present.

  9. Thank you Tallis for the article.
    Could you share some links to online gps graphs and so?

    Dragons, the link under the first map doesn’t work.

    Link fixed


    Some really nice images. RUV has reported that the lava fountains are now a lot taller, the high bursts as seen in the above images are now more than 100 meters. I think we wil lget quite a show as thsi thing evolves, especially if the lake around the vent starts to shrink as the outflow becomes more focussed. It is hard to see the eruption right now but it also looks like the central fissure is a lot more singular now, it is almost a single vent. Nothing on whether pressure has been equalised in the system, but as there have been no reports the effusion rate has increased I am assuming this has not changed and more vents could still open. Or the existing one might get more powerful.


    • The weather is terrible but the occasional glances show that the fissure with its three parts remains active. Impossible to tell whether it is fountaining more. The cone is not building fast, suggesting most of the output is streaming, not blowing

      • The fountains are not necessarily higher but the taller jets are happening more often than early on. It also is definitely more focussed on the middle fissure too, the two edge vents are not so active as before. But they are all still going, and with that big quake showing there is still pressure underground… I dont recall last year that any of the other vents had a precursor other than the first vent slowing a bit in the preceeding hours.

  11. Large quake just west of Kleifarvatn. There have been quakes here before

    • Triggered quake on a pre-existing fault? or not? It’s c. 5km depth.

    • Trigger quakes from the dyke expansion. Question is if it’s a delayed response or if the dyke is still expanding.

      • Would that imply a higher rate of feed than the current eruptive rate?

      • My guess is that the dyke is still expanding. Swarm sequences tended to start near Krysuvik and meander westward. But I could be wrong.

        • There was earlier mention that the pressure in the dike was not relieved by the eruption starting and that new vents should be expected although there is no indication exactly that they will form. I did find that the vent actually erupted in the lowest elevation spot in the ground above the dike, so maybe now the vent has built up and seems to be forming a cone it might encourage new breakouts. New vents opening through the eruption is probably not really that weird for this style of activity either, just that in recent decades most Icelandic eruptions have been quick and dont last too long. The last eruption like we see today might have been Surtsey.

          If the last cycle is an indication then Fagradalsfjall is going to be highly active for at least a decade and probably longer, probably the whole rift from Natthagi to Keilir will be a lone of large cones and shields in 30 years time.

  12. The RUV camera is looking the other way. Is there something we don’t know? Or has the operator dozed off and knocked the control lever?
    BTW I stand by my theory another rift may open to the SE of Keilir. You first read it here!

    • Rumour says it ran out of power during the rain and now it got stuck while moving on it’s regular pan after power up.. Don’t know if this is correct.

    • I think the operator subscribes to your theory and is aiming for any further fissure there. A bit early, perhaps

          • Oops I just noticed that 2 minutes before you posted Albert. So anything could be happening their, I was hoping for a more interesting fissure. 🙂

  13. What is the area like around Chiles-Cerro Negro? Volcanic field, rhyolite domes?
    Definitely appears to be surrounding older calderas, and magma is clearly closer to the surface than before.

    • I would say looking at the earthquake history there are potentially 3 magma chambers, one between Chiles and Cerro Negro, closer to Chiles. Another to the South-east, likely deeper. And another further to the south-east where an old likely Pleistocene caldera appears – though this could just be stresses causing the quakes.
      Some Dacitic domes and the magma composition hovers between basaltic, andesite and dacite.
      I’d say this isn’t quite fully developed into a VEI7 volcano yet but may have some large eruptions in between.

      • This is not particularly on topic but it seems like a good lead in for a question I had:

        What made Tambora a VEI 7 capable volcano, and isn’t the caldera undersized for the enormous amount of tephra produced in 1815? Does that imply a very deep magma chamber? Speaking of, I believe it erupted trachyandesite which isn’t at the extreme end of silicic magma, so wouldn’t that mean the chamber probably wasn’t even sitting for very long? I read Tambora was dormant for “a few centuries” prior to 1815, but that doesn’t scream “VEI 7 100km^3 + of tephra” to me. Do we know what Tambora’s older eruptions were like? Is this the first time it went big?

        And yes, thinking of it in relation to Chiles – Cerro Negro somewhat. Even Tambora’s extant edifice is enormous, so it clearly has a large magma source. Just curious how it all added up, and if we can infer anything about Chiles (not suggesting they’re necessarily the same scale).

        • All of the stratovolcanoes in that part of Indonesia are huge, I dont think it is higher magma so much as that they are very stable, calderascare refilled by more stratovolcanoes and repeat. Rinjani is also still mostly intact, it could be that magma chambers are deep here or are more veryically oriented, or perhaps that conduits get so wide they act as a chamber themselves?

          It might also be that they simply go caldera under their own weight, not anything to do with magma evolution, while no Mauna Loa these volcanoes are some of the biggest freestanding mountains on this planet.

        • That is a very interesting question to ponder about. It seems to me that Tambora was a massive mafic volcano, and I’m not sure if it should be called a shield or a stratovolcano.

          Tambora has low silca alkalic lavas, most of the data samples on it are trachybasalts and basaltic-trachyandesites. The lavas are thus similar in composition to Etna. Etna is a volcano that has erupted mainly trachybasalts historically, and in prehistoric times basaltic-trachyandesites have been common too.

          The slopes of Tambora are covered in voluminous lava flow fields formed during long lasting eruptions. The lava flows are in places more than 100 meters thick and have complex structures with many numerous overlapping sheets of lava, building rootless shield-like structures fed by lava tubes. Probably some of these flows are over 1 km3 in volume. Large cinder cones that erupted from the flanks of Tambora fed many of these flows.

          Here are thick lava flows with prominent rootless shields in the upper slopes of Tambora that were erupted from some vent now obliterated by the caldera collapse:

          Here are 2 young flank vents in red, and their lava flows in green:

          Given that most of the erupted volume seems to be lava flows and that the slopes of the volcano are relatively shallow Tambora is more of a shield volcano than a stratovolcano. It stood about 3600 m high or more before the collapse in 1815. The 1815 lava was crystal-poor trachyandesite, more evolved than earlier lavas, but still only ~55-57 % SiO2, Kilauea is 50 % SiO2 in comparison. However one should take into account that alkalic magmas like Tambora’s don’t get as silicic as more common subalkaline magmas.

          • Seems definitely there is a case to be made that it fell in on itself rather than evolving a large silicic magma chamber. Maybe it began at a flank vent underwater that set it off to go caldera properly. I do recall that Tambora had been erupting for several years before 1815, in a more strombolian manner. Doesnt seem it was exactly primed to self destruct unless it was induced into it prematurely.

            It does actually give a lot of thought into what could potentially happen at some of the ‘harmless’ volcanoes though, if ring dikes can make even fluid volcanoes explode. I always did think some of the Hilina formation looked like ignimbrite, and the lava flows seem a lot bigger than those erupted recently there, maybe Pleistocene Kilauea was a real monster, ignimbrites and summit fissure eruptions of massive scale.

          • It had been erupting for a few days prior to the big explosions. There is one report of ash fall in the years before the eruption – I would have to look up the details. It also developed a steam cloud a few years before. That indicates heat but no eruptions: there is plenty of rain here to provide the moisture for the steam. But by and large it was not recognized as volcanic in the years before the big one. The entire kingdom that lived on the slopes of the mountain was wiped out, so ancestral memory may have been lost. But it is likely that it had not erupted for quite a few centuries. We have never seen a VEI7 develop. Pinatubo is the largest eruption for which we have some idea of the process, and it is tiny compared to a VEI-7. I expect that dormancy is a fundamental part of large eruptions.

          • Is Pinatubo bigger than Hunga Tonga Hunga Ha’apai? Been quite some sources recently that show this years eruption was probably a bit bigger, at least they were very comparable. And both of course volumetrically much less than a VEI 7.

            But Hunga Tonga does have one thing in common with Tambora that Pinatubo didnt have, the magma. Both were crystal poor andesites differing only in their alkalinity, where Pinatubo was a crystal rich dacite that was probably more rhyolite with intermediate crystals. Tambora and Hunga Tonga were much closer to what is erupting at Kilauea or Fagradalsfjall now than to the magma of Pinatubo which is so viscous it doesnt look like a liquid and is basically partly molten granite that ends up on the surface. Pinatubo basically erupted big right away too, within a fortnight of showing obvious activity at all. Hunga Tonga erupted for a month at moderate levels before blowing up, and with two eruptions in the prior 15 years, it was much more active long term. Tambora seems may have been the same.

          • Hunga Tonga was an accident in an otherwise unremarkable eruption. In that it was a bit like Krakatoa, described by Vermeer as significant but not important until it blew up completely. Tambora was a different beast. It had no sea water, and did not suffer a flank collapse (which seems to me triggered HT to go nuclear). Instead, the top kilometer of the mountain just took off. The differences appear more important than the similarities

          • The bathymetry for Hunga Tonga doesnt show a collapse scar indicative of a sector failure, but a round caldera a lot like at Tambora only not as big.

          • Any underground explosion will leave a round scar. That is why meteor craters are almost always round even though very rarely hit straight down. The crater of HT is off-centre compared to the eruption site of the previous days, which is why I suspect a flank failure

          • The caldera that formed is centered on the platform that existed at shallow level, presumably an older caldera filled in. The historical vents were all on ring faults, including the 2022 eruption. The big blast was a full ring dike failure. For whatever reason eruptions before 2022 generally preferred to use the fault close to the old islands, but some were elsewhere like in 1988.

          • Regarding the composition of Tambora, Tambora is a very alkaline volcano for a volcanic arc, there are probably few other volcanoes in the Sunda arc that can compare. Its 1815 ejecta was straddling the boundary with tephriphonolites. So it is closer to the evolved end of its series, trachyte, than to the mafic end, which is presumably alkali basalt. However its series doesn’t gain too much silica as they evolve.

            Regarding Hunga Tonga the shape of the collapse is like would be expected from a vertical collapse of a magma chamber roof. It was theorized at first there may have been a flank collapse, but when the bathymetry was acquired the volcanologists leading the survey discarded this formerly preferred idea due to there not being much change to the flanks. The new caldera is in the center of the mountain exactly where it should expected to form it, surrounded by a ring of vents from historical and prehistoric eruptions:

            Note how this relates to the structure of pre-2022 Hunga Tonga. The pre-2022 caldera is marked in green and coincides with the the 2022 caldera. The vents are marked in red circles and show a circumferential pattern surrounding the caldera on its southern side mainly. The vents were likely fed by cone sheet intrusions in a manner similar to Galapagos volcanoes. The inflating caldera likely favoured the occurrence of such intrusions.

          • The 2014-2022 vent was not fed by a cone sheet however, not likely. Because it formed inside the caldera, the cone sheets breached the surface outside the caldera, mainly to the south. It was an anomalous intrusion. Maybe because of that reason the 2014-2022 vent was able to collapse the caldera, the conduit may have had some characteristics that allowed to drain more efficiently the magma chamber.

          • The 2014-2022 cone is also located where the former pre-caldera stratovolcano stood, which is interesting.

          • The vent that erupted prior to the main eruption was on the northern island. We know that because the explosion left a small crater. It doesn’t seem that these eruptions were large, and little magma was involved. It seems unlikely this on its own was able to collapse the magma chamber. The eruption was however rather close to the slope into the central crater. We don’t know what happened under water. The ring had not risen notably prior to the eruption, and any inflation went unnoticed. There must have been a major weakness somewhere. My impression is that the slope was the weakness. It gave way, and this provided the initial escape route. This is pure conjecture, but I would envisage that the opening on the flank let the gas escape. These were the first explosions of the big eruption. This reduced the pressure in the magma chamber. The roof cracked, water came in turned to steam. This explosion removed much of the roof. Now the magma lost all pressure, and the explosive decompression caused the big boom, taking the exposed water with it. It was a very water-rich eruption, suggesting to me that the water in the crater was directly exposed to the force of the blast, not shielded by a kilometer of rock. Anyway, pure speculation.

          • I have made a kmz for Google Earth with lava types and I’m surprised to see that there are a lot of alkaline volcanoes in Sunda. Slamet, Muriah, Merapi, Bromo, Lamongan, Batur, Rinjani, Tambora, Sangeang Api, Lewotolok or Batu Tara, all of these belong to the alkali basalt-trachyte series, except Batu Tara and Muriah which are of the basanite-phonolite series. Sunda seems to be one of the more heavily alkaline volcanic arcs, although there are also other arcs with a substantial number of alkaline volcanoes like Vanuatu, the Trans-Mexican belt, or Italy.

            Others are subalkaline like Dieng, Kelut, Agung, Lewotobi or Iliwerung, while most don’t have many data samples on them.

  14. An eruption of this in the future is something I’ll wait for. Hopefully they evacuate everyone safely and there is minimal damages though.

  15. This cam now focussed on smoke well away from the new eruption.

    • It has grown from wispy to very noticable in a very short time.

      • It also appears to be on the same rift line but close to what looks like Kelir

  16. Oh dear, just seen that the time stamp isn’t moving so anything could be happening there in reality!

      • Yeah, Fiji is a relatively active volcano. That is why it is such a beautiful cone, little time for erosion. It had an all-ash VEI 5 eruption in 1707-8, which was a flank eruption, preserving the cone. It is a repeat offender with VEI 5s around 1350 BC and 900 BC. There was also a *huge* lava eruption in 864 AD, which covered about 30km^2!!! Lots of other smaller or poorly recorded eruptions. It also had a flank collapse around 300 BC that caused Lahers. In summary, it is no friendly giant, and is likely to do something decidedly nasty in the next couple hundred years.

        • RE:”and is likely to do something decidedly nasty in the next couple hundred years.”
          Much like St.Helens and others of its ilk, such an event would be a tragedy of many proportions.

          • I was surprised to learn Mt St Helens had a VEI 6 eruption a few thousand years ago. I believe it’s called ‘Tephra Layer Yn’.

            Couldn’t find an estimate of actual volume, but from the images of the deposit it was a mighty big eruption.

          • A quick estimation of the total volume of the pumice layers gives me 10-15 km3.

          • I own ‘The 1980 Eruptions of Mount St. Helens,Washington-Lipton and Mullineaux, Eds. The first paper is by Mullineaux and Crandell: “The Eruptive History of Mount St. Helens’ It contain’s a plethora of information lacking only in VEI’s for the many events.

    • Fuji been insanely active earlier in Holocene .. it have been a Japanese Klyuchevskaya Sopka for a long time it seems. Most of that upper cone is holocene product If I remebers correct
      Its Activity must have looked similar during its construction phase

      Enclosed by mountain ranges this must be as close as you can get to a Japanese Mordor 🙂

      • The beautiful cone is a sign of young age. St Helens had that shape before it blew up, and one day will look like that again. That suggests that one day Fuji may look like St Helens does now, and Hokusai’s master piece of the 36 views of Fuji will be out of date

  17. Reactivating after 12,000 years does seem a bit ominous. Might be a bit more evolved than andesite.

    • There was a discussion on this a while ago, the magma is andesite overall but it is actually more rhyolite with mafic crystals, the actual liquid melt is rhyolite. In volcanoes that erupt only rhyolite usually they sit on top of a huge heat source, often a massive basaltic intrusion complex (hence why they are bimodal) so despite being high in silica it heats it up a lot so crystals can settle out. But in the Andes it seems the magma is not hot enough to do this, at least not typically. This isnt always the case, the southern Andes has abundant mafic volcanism and very hot rhyolite, and Reventador which is not that far from Chiles Cerro Negro erupts hot andesite, but it seems actual crystal free andesite magma is not too common in the Andes despite being the namesake… It might be why andesite is imagined as a viscous magma, if it is rhyolite with mafic crysyals in disguise, because andesite melt seems to flow easily if it erupts crystal poor.

  18. Meanwhile, Taal is acting up again, SO2 yesterday 17K or so and this:

    • Taal is always one to watch. Phivolcs should raise the alert to 2 since it looks like there is some more shallow magma and good deal of it seems.

    • Albert, due to this picture I made another timelapse. (link some posts below)
      Thank you

      • The power and the glory. Earth and sky. Dawn on fire. I hadn’t decided on the right title!

  19. Just noticed this actually, another thing from Hawaii that I have missed 🙂

    Quite substantial deep earthquakes under Kilauea, same depth as the Pahala swarm but going right up and under the caldera. Ordinarily I would think these to be settling quakes but the location here is going to make that difficult.

    • Those two swarms are probably faults. The deep swarm under Koae, and the deep swarm under Volcano Village, I’ve seen them quake many times since 2018, sometimes looking for surges of magma going up to Kilauea with not much success. Usually these swarms follow mainshock-aftershock sequences. Normally there is an ~M 3 earthquake and a couple of small earthquakes that follow. These two clusters are part of the Mantle Fault Zone that connects with Pahala. The origin of these faults and the stresses driving them remain a bit enigmatic to me.

  20. I would guess it is the same stress field as causes the decollement fault, acting at a greater depth. I am inclined to think it is related to both Kilauea and Mauna Loa. It moves away from Mauna Loa, or at least the general direction of the middle of the island, and Kilaueas magma system goes through it so I have a hard time seeing it not being involved even if it doesnt indicate surface change so much.

    It also looks like Kilauea is totally open now, lake signals exactly respond to DI events, and the most recent insar shows no deformation on Kilauea, it is an open hole in the crust again with all of the magma going to the lake. There is probably some south flank sliding though as the cross caldera is getting wider.
    Mauna Loa most definitely looks like building to an eruption soon though,it is now silently inflating, so is open to the depth of its magma chamber just like Kilauea was after 2018 and before it began erupting again. Question is if we should expect a small eruption or a very big eruption after a long break like this, it has been inflating for a long time since at least 2004 and the 1840-1950 high activity period didnt end with a caldera collapse so the shallow system presumably still exists there from that time, there could be a huge amount of magma at play here potentially.

  21. This whole comment thread has just given me even more thoughts on this volcano that will require another article, and the next one will be the biggest and most extensive article that I’ve ever written on this volcano but it’s gonna have to wait for more information. It’s gonna have to wait till early September.

  22. Hey RUV, I guess you thought a new fissure was about to open north of the existing one, but it’s been half a day and there’s no sign of a new fissure so clearly you were wrong. Can you please just give up on it now and point the Langholl camera back toward the fissure we actually do have? Thanks. :/

    • It’s not pointing that way on purpose. The camera has been frozen in that position since yesterday (note that the timestamp on the lower left hasn’t changed since then).

    • It’s not operating, just shows the same frozen frame. They will probably fix it when the weather conditions allow for it, but right now it’s not possible. If you look at the cameras that do work the visibility at the site is zero anyway, so even if it was operational you wouldn’t see anything.

  23. Grimsvötn as well been inflating constantly since 2011 … I wonder If the next eruption will be big or small .. No Idea. Its one of Icelands largest magma systems. But having large shallow magma chambers makes them difficult to pressurize, unlike Fagradals that erupt directly from source.

    If I remebers correct the upper chamber in Grimsvötn contains around 40 km3 of magma ( Thats quite Big for shallow chambers in basalt volcanoes ) Althrough not all of that is eruptable ( melt mush ) paper. Grimsvötn Maybe similar to Axial Seamount in its magma chambers

    Kilauea is unique with a supply so high it can pressurize large chambers in an instant and it can erupt non stop

    • I guess its also the spreading with most of the magma going to passive rifting, ending up as gabbro in huge underground stoorage regions. Most of Icelands Igenous mass is probaly mafic plutonics rather than lava flows. With the shallow crust being lava flows. And that makes Iceland more like a ”Mafic Continent” rather than a pile of lava flows. Althrough Iceland is still technicaly a LIP oceanic mafic Province.. and not a true continent

    • Eruptions in the dead zone are rather huge, one series of lava flows Veidivatnahraun are bigger than Thjorsahraun I think, its probaly caused by deep rifting over large magma resovairs thats accumulating for a long time, with these resovairs are in turn feed by the hullboat mantle decompression melting below them
      But souch events are rare and only happens When there is pent up strain there

    • There are two kinds of mafic LIP s

      One is the Classic fast one like CAMP and Siberian Traps with Mega lava flows building up a many many pile miles deep ( Ontong Java is 30 km deep of pressed down lava flows ) givning them their trap like apparence most of their thickness is lava flows and little plutonics just in the ”basement”

      The other type of Mafic lips are far slower ones, that lives for millions millions of years, with lava flow activity and intrusions their piles are composed of lava flows and intrusions, with more intrusive mafics the deeper down you go into the pile.
      Basicaly forming a ”short lived mafic volcanic continent” Iceland coud also be an illusion of a LIP .. just the Iceland Hotspot having it easy to lift up the shallow spreading ridge from the ocean and thicknen it from excess volcanic activity. But Icelands Plateaus million of cubic kilometers of Magmatics and Extrusives does pass the Word for a LIP in my opinion as well

    • Its also very difficult to know how much of Icelands large magma production really is from the Hotspot or from the Hotspot + Ridge combination, the mid ocean ridge decompress the Hotspot after all.
      I go for a Hotspot a bit weaker than Hawaii and its more spread out… still Iceland is with certainly the worlds 2 th most powerful oceanic hotspot.
      It coud also be that the passive robbing of magma prevents us seeing the true strenght of the Iceland Hotspot

    • Still I too give Iceland too the defenition of a large oceanic LIP its have the hallmarks of that Massive magma production, miles thick lava flow stacks, and a thoelitic composition and quite alot of materials in short time.

    • If the really huge Extinction Level LIPs erupted from a single source of magma decompression point region
      ( as seems to be the case ) and their large ammounts of lava sheets in forms of Traps and Giant dykes leading to one single point

      Then Siberian Traps and Deccan Traps and Ontong Java Plateau coud perhaps be seen as ”Single Mega Volcanoes” on a catastrophic scale Making souch volcanoes the Most disasterous edifices in the entire solar system… 🙂

      Althrough the much smaller Columbia River Basalts where sourced from many diffrent chambers so was not a single volcano

    • Think Oraefajokull is the most dangerous, inflation for a long time, large system, history of VEI4+ eruptions, erupts rhyolite. Grimsvotn is in sync with Bardarbunga and seems to have a delicate balance of erupting regular mid-level eruptions.

  24. Icelandic S&R have rescued ten tourists at the eruption site
    via giggle translate, it’s surprisingly decent

    “Two groups of tourists, numbering about ten people, were rescued by the rescue team at the eruption stations just before tonight. According to the rescue team, the tourists were cold and driven.

    Rescue teams from the south-west were called out shortly before four today because of groups of people who had lost their way near the eruptions at Meradali. The Coast Guard’s helicopter was also in the area, but the conditions for an aerial search were not good.

    The area at the fountains has been closed since around five yesterday morning due to the weather and work on the hiking trail. Despite that, it seems that many people did not heed that advice and decided to make their way to the hot springs.

    According to Davíð Más Bjarnason, Landsbjargar’s information representative, rescue teams found the two groups that were being searched for, but the groups totaled about ten people. Although the two groups have been found, rescuers plan to continue their search at the volcanoes to rule out any suspects.”

    • Easily done in Iceland. Even summer weather can be dangerously cold, and tourists can be caught unaware. It happens in the Manchester Peak District as well. Great job by the rescue teams.

      • It’s actually startling the number of tourists I’ve seen there dressed completely inappropriately. If you’re spending any time at all outside, it’s not the place to wear jeans and sneakers, with a cotton hooded sweatshirt for warmth.

        I get that good hiking clothing is expensive, but there’s plenty of inexpensive options. Everyone should have a waterproof shell top and bottom, and some good compressible synthetic or down layers in a backpack.

        We go when it’s a bit colder there, and it can get REALLY cold REALLY fast. When you’re out for hours and hours, it’s not a trivial issue.

        Yet we see tourists shivering and soaked in just about the worst clothing choices possible.

        • I was taught that as a city-bred child.
          Nowadays with any risk of being out in rain, I pack lightweight waterproof overtrousers. Makes a HUGE difference and packs down into a tiny envelope.
          Its good for wind protection too.
          That, and a cheap fabric non-breathable lightweight anorak and you are pretty good with enough underclothing.
          PS I now use ex-military ‘fake goretex’ lightweight anoraks. Totally waterproof, relatively cheap and more durable than lightweight.
          Currently lomg pattern german traffic police, belgian standard anorak and desert zippable overtrousers (can’t roll up and put in pocket though).

          • Exactly.

            You don’t need to walk around in Arc’Teryx or Rab, but you should have clothing with some good protective synthetic materials to keep you warm and dry.

            A good moisture wicking fleece and baselayer is also important.

            Especially on the trek to Fagradalsfjall. Pretty legit hike especially for people who may not be that comfortable with the outdoors but want to see the volcano. I can absolutely imagine a group heading out, some not properly dressed. Then encountering bad weather, losing visibility and getting progressively colder and wetter until they’re feeling panicked and lost and have to call emergency services.

            Dress appropriately and head the weather forecasts and warnings of Icelandic authorities.

            That’s how you go and love every second of your time in Iceland while staying safe.

  25. Another timelapse from 2 MBL webcameras last night

    By the way, the links are unlisted in YouTube, you can’t find these without having the links
    (I am a bit cautious as long as I don’t get an official permission – or lose my patience)

    • Beautifully atmospheric. The timelapse brings both the eruption and the scenery to life.

    • Absolutely amazing. Could be another planet, or perhaps a wizard will pass by the camera.
      Vastly better than real time.

    • Nice lava boat going down the stream in the last sequence. It’s difficult for the vent to build a proper cone when it keeps sailing away with the lava.

      • It is building a nice pond though. Part of the reason why the cone keeps floating away. Once the holes get stopped, the next outflow could be in any direction. It is creating a lava shed where the lava can go either way

    • Thanks very much for that timelapse Virtual. Everytime I have checked in to see if visibility has improved the weather has sti;; been terrible but these timelapses are easing the pain of seeing grey screens. 🙂 so many thanks for your time spent producing these.

      • Seconded. But I think we can give Virtual the day off. Views today have been wet and monotone. The weather forecast has the first sunshine scheduled for midday Sunday, lasting one hour – with the next break on the following Saturday. We can hope for slight inaccuracies in the forecast!

    • Says it was recorded in March, even though it is livestreaming. I dont think Taal has erupted since then, although if it does something else before the end of the year I would not be surprised.

  26. This alarm is completely unwarranted.
    It is a volcano not very different from Sinabung in Indonesia.
    I have read several times on this site about allegedly dangerous volcanoes such as Iwo Jima, Taal and now Chiles-Cerro Negro.
    You will see that even this latter volcano will eventually prove to be completely irrelevant.
    The number of earthquakes in August 2022 has already dropped very low.

    • First, Taal and Ioto aren’t “allegedly dangerous” they are actually dangerous especially Taal. Second, what gives you the impression that this volcano is just like Sinabung? Sinabung is smaller, younger, and more active but most importantly, when it became active again some years ago, the swarm was smaller, the deformation was less extensive, and the activity was wholly confined to Sinabung alone.
      This volcano has produced extensive swarms with pauses in between that have lasted up to 2 years so just because quakes are going down now doesn’t mean the volcano is finished

    • Sinabung is nothing like Tallis’ volcano. And Sinabung is one of the most deadly volcanoes of Indonesia, with regular eruptions and fatalities.

      • I’m actually laughing at calling it Tallis’ volcano.

        Imagining “Tallis Rockwell” written across its slopes in the style of the Hollywood sign in California.

    • I think what AL means by being similar to Sinabung is the effusive dominated eruption style. In the past Chiles has done such eruptions mainly consistent in lava flows, as far as I know Chiles has no major explosive eruptions known. I’m not saying though Chiles won’t pull off a cataclysmic explosive eruption, or a lateral blast, or something hazardous, there is always a first time. But this is different from when Pinatubo woke up for example and geologists quickly realized Pinatubo had done several VEI 6 eruptions in the past, and that in fact doing a VEI 6 was the normal thing for Pinatubo.

      In the Nyiragongo article it was discussed the possibility of Chiles waking up to a new period of stratocone building, and this is a realistic option I think. Looking for a worst case scenario like Talllis is doing is also important. But I do see what AL sees.

      • Fully understand the point being made.

        Chiles may do nothing for an appreciable amount of time, or it may burp once or twice, or it may have an effusive event whether minor or major. Or, like we discussed (and thank you for all the information you provided above), it may have its “first time” large explosive event as Tambora did after predominantly effusive activity (NOT suggesting similar scale).

        We can’t know how this will play out. I think it’s important to be aware of it as a threat, and to be monitored with the utmost capability of the local agencies.

        Beyond that, I do agree with Tallis that it’s nice to discuss explosive volcanism for a change here, as much as I enjoy learning about Fagradalsfjall (and I really genuinely do).

    • Thanks, it even has a lens wiper; that must be a first for the Iceland webcams.

      • Looks like it’s in a car that’s parked there while they are doing some work at the site. Will probably end soon.

        • You’re right; it was just a temporary stream that lasted less than 2 hours. It appears that “Live from Iceland” doesn’t have any continuous livestreams of its own; they are just copying the MBL and RUV livestreams.

    • It looks like not much has changed there really, all the vents are active and the pond is still there, although higher up.

    • It’s a dashboard camera belonging to one of the webcam maintenance guys. He commented in yesterday’s DrFox2000′ livestream. There may be another today.

  27. Actually, based on this video, it looks like the middle fountain has started build a real cone. Not fully closed yet, since the front is still open to the lava pond, but the back and sides have built up some material.

    Naturally, those built up cinders could easily float away as lava boats at any moment…

    • Which one will deliver us our epic VEI 6+ eruption? Will it be Taal the Tiger, Ioto the Beast, or Cerro Negro the mysterious? Place your bets below!

      • Ioto seems much more of a safe bet, Cerro Negro is a big unknown and at least outwardly doesnt look exactly like it is about to go caldera or likely to do so over other options, and Taal is very variable in the scale of activity and seems to not erupt as much in the way of magma, just it is very explosive with all the water around. Ioto is what looks like a near exclusive caldera volcano, it goes big or not at all, to me it is nearly a sure case for a massive eruption, just it is not clear whether it is actually close to blowing up as it might look.

        Magma for Ioto is shoshonite (like alkaline basaltic andesite) and trachyandesite, so not particularly evolved but similar magma to Tambora…

      • I called up a paper on Ioto’s Motoyama eruption before heading to work and I’m excited to check it out when I get home.

        It’s interesting how such extreme ground deformation is tolerated and contained at Ioto relative to all other systems that I’m aware of. Campi Flegrei too, but not this extreme.

        Is it something of a unique trait (that Ioto can show this much uplift and also contain it), or is it indicative of a near future eruption? Whether soon or in centuries.

        Superficially it looks like a pimple that’s about to pop, but I wouldn’t call that a scientific analysis.

        • The older papers called it a ‘resurgent dome’ and those tend to be harmless. But I doubt that it is correct. There is a lot of heat involved combined with water – it really is a time bomb. The rate of inflation is unique and has not been constant (as a resurgent dome should be) – it has fluctuated in the last 1000 years. We hope for the best but don’t rely on it. Carl pointed out that some of the ‘eruptions’ were explosions from old ordinance. The location of July’s explosions has shown activity before and it is likely a developing hydrothermal vent. Henrik’s old post is a master piece – although it does overstate the magnitude. Ioto has done VEI-6 in the past and will do so again

        • Ioto is modeled pretty well by assuming a starting Caldera floor 200m below sea level and a dome 320m tall in the center and 80m at the edge of the Caldera (based on beaches and historic uplift, seems Suribachi which is on the caldera rim has about 1/4th the uplift of Motomoya). Naturally it isn’t quite a perfect dome, but that gets the size of the actual island right and seems to roughly match the slope. That would be roughly 17km^3 added in volume. Except, that is just inside the caldera, based on Suribachi, it seems likely there is some uplifted outside the caldera. It will also have some downward pushing too, so it seems likely it has averaged nearly 1 km^3 per century since its eruption around 750BC. Now a lot of the dome is compressed tephra, so it may not be quite dense rock equivalent, but it probably could still do a high-end VEI 6.

          It does seem to be slightly more active the past few decades, but do not think the odds are particularly good it happens to go off. In about 2000 years, the whole caldera would be an island. I suspect it will burst before then, but that still gives a wide range. By then, it might be able to do a low-end VEI 7.

          It would be really bad. Henrik got a little overexcited, but it could be nearly an order of magnitude larger than Hunga Tonga, though with proportionately less water involved. Tsunami height for Hunga Tonga is hard to get a feel for because of the reefs, but at the distance of China from Iota, it seems to have been over a meter. Henrik said 20 meters when it would hit China. Scaling up, I doubt it would be more than 10 meters when it hit China (could easily be much less if Ioto does a series of large explosions rather than largely doing it in one go), but that would still be *incredibly* devastating.

          • Thanks for your thoughts. Any knowledge of whether there are historic or prehistoric tsunami records in China? Not a traditional place to expect tsunamis, but I would expect that at the minimum, the Kikai eruption could be a relevant proxy for what a regional volcanic tsunami could potentially do to China.

      • I bet Ioto will deliver eventually, but probably not in our lifetimes.

      • I suppose to say is Taal has the best chance, but it also has a much greater chance of doing a lot of small eruptions than anything big. Chilles Cerro Negro is really probably too much of a wild card to be sure, but past behavior is more towards construction than destruction, so maybe anything more than a VEI 5 is best considered a remote possibility. Ioto really just looks like it is an impending disaster, I would have assumed it to still be a ways off but if it erupted some actual magma recently that might be a big change. Trachyandesite is not very evolved and probably not that viscous, but it is very volatile and seems to be highly explosive, Tambora was as big as it was and had such a huge effect on the climate because it erupted thus magma. So Ioto is basically a Tambora at sea level.

        NDVP put Ioto as the most dangerous volcano of them all because it could wipe out the coast of a lot ofAsia with a tsunami. I think it would not be powerful enough to displace so much water to make a dangerous wave at such distance, it isnt like a thrust fault, it is a point source (also same reason Cumbre Vieja or Mauna Loa collapsing wont wipe out the opposing distant coastlines), but the eruption might have some serious climate effects especially if it can go mesospheric as we now know for certain that some eruptions do.

        • What makes trachyandesite particularly volatile, gas content? Is that more a feature of specific trachyandesitic volcanoes or an inherent quality of that particular magmatic chemistry?

          Like how melitites and nephelinites seem to be extreme gas rich?

          • It says on Wikipedia that magma with this composition is usually enriched in a lot of the elements that have major climate effects, sulfur being particularly mentioned. I imagine the 1815 tambora magma probably looked a lot like what Hekla erupts, or what Kilauea erupted at fissure 17 in 2018, not especially viscous, but those were not high in volatiles so erupt effusive. Yes Hekla is mostly effusive it just likes to start off with a bang 🙂

            Probably Hector will answer better.

          • The more alkaline the more gas rich as far as I’ve seen. Fluorine, chlorine, carbon and water all go up substantially as you get more alkaline/potassic. Sulphur seems also a little more enriched but not as much as the others. I have never checked inclusions from trachyandesites though.

        • It could potentially be nearly an order of magnitude larger than Hunga Tonga based on the likely uplift since the last eruption, mid-to-high-end VEI 6 versus high-end VEI 5. China is about the same distance from Ioto as places like Norfolk or Vanuatu which saw slightly over a meter of surge. So 10 meter tsunami along most of China’s cost and a little more for Japan is about the max I think is realistic.. Roughly half Henrik’s numbers in his NDVP post for Ioto, which I think is a stretch now, if it manages to wait two thousand years to burst, maybe then. Given most of Shanghai is less than 10m above sea level, that would still be ***very***, almost incomprehensively, bad.

  28. The fog has lifted 🙂

    Fountains are definitely a lot higher, there is also a proper cone too. I think this eruption is going to last a good long time now.

    • Any updates on the eruption rate? Still about the same, just consolidating its vents?

  29. Yesterdays update concerning Meradalir eruption noted by IMO:

    “”The National Defense Science Council met this morning about the volcanic eruption on the Reykjanes Peninsula. The latest data and measurements were reviewed to assess the situation and the continuation of the eruption. Is it the opinion of scientists that the progress of the eruption is as expected. The eruption activity has remained quite stable for the last few days and it is important to prepare for the eruption to last for quite a long time.

    On satellite images showing land changes on the Reykjanes Peninsula since the end of July, you can see signs of deformation a little northeast of Grindavík (See the area inside the black box in the picture below). The deformation seen in the satellite images is at the source of the earthquake that occurred on July 31 and measured M5.5. At the Scientific Council meeting, other data from the region were reviewed, e.g. GPS measurements, earthquake data and they show no evidence that magma is on the move and the most likely explanation is surface changes that occurred during the earthquake about 10 days ago. Nevertheless, researchers will collect more data to further confirm that this is the case. It was discussed that it would be important to increase monitoring even further in the metabolic zones that can affect nearby settlements by installing more measuring devices for real-time monitoring.””

  30. I wonder about the ouput rates of the current Meradalir eruption.
    Not much news from the University yet.

    “”August 9, 2022 – First results of chemical analyses

    The weather has not been suitable for flying in the last few days, but samples of lava and gas have been processed. Primary chemical analyzes of samples from the first days of the eruption in Meradälar show that the basalt magma is very similar to the one that erupted in September 2021.

    The composition of the gas (proportion of carbon dioxide and sulfur dioxide) points to a deep origin of the gas. Further interpretation of the data is underway.””

    • The reason for lack of updates is in the quoted text: “The weather has not been suitable for flying in the last few days”

      Output rates are measured indirectly by assessing the total volume of erupted lava through 3D-models created through photogrammetry, i.e. by taking photos from an airplane and putting them together in special software to obtain the 3D-model. The difference in volume since the last flight divided by the time between measurements is used for the flow rate.

  31. Not sure if it was mentioned before here, there is an open acces publication available about the magma flow rate in the 2021 Fagradalsfjall eruption.

    Volume, Effusion Rate, and Lava Transport During the 2021 Fagradalsfjall Eruption: Results From Near Real-Time Photogrammetric Monitoring.
    Gro B. M. Pedersen,Joaquin M. C. Belart,Birgir Vilhelm Óskarsson,Magnús Tumi Gudmundsson,Nils Gies,Thórdís Högnadóttir,Ásta Rut Hjartardóttir,Virginie Pinel,Etienne Berthier,Tobias Dürig,Hannah Iona Reynolds,Christopher W. Hamilton,Guðmundur Valsson,Páll Einarsson,Daniel Ben-Yehosua,Andri Gunnarsson,Björn Oddsson

  32. At last the rain has cleared in Iceland. Interesting to see the development of the world’s first “sofa” volcano. A full three-seater, too. I wonder if DFS will get in on the act?

  33. On the “Keilir” stream (not located at Keilir) it shows that lava has started to spill to the southeast out of Meradalir and also a large amount of Meradalir has been repaved.

        • Thanks! It has a different name at acme but I can see why ‘Keilir’ fits. It is very hard to see how far the lava has come. The heat signatures stopped half way, and I therefore think that the left valley has not yet been reached. The light coloured part is I think the moisture from last night. The dark part are later flows from last year’s eruption. But I am happy to be corrected

          • The light part is last year’s flow, and the dark part is the current eruption. You can see that the dark part has moved to the right (east) by comparing Virtual’s last timelapse above (near the end) with the last good view on the Keilir webcam (around 14:30 today, Aug 10).

        • Albert it’s definitely got right across. It has about 1 m height to go to start moving out of the valley, see my reply to mjf below.

        • If you go back to around 12.30pm on the Keilir webcam, it’s more obvious that the lava is beginning to bulge as it approaches the saddle area. I saw a vehicle parked there , probably the people that took the photos.

    • mjf — Your use of “repaved” made me laugh. Thanks for that.

      I wish we had a “before” and “after” photo. It’s difficult to tell what is new and what is old.

    • On Facebook it was reported an hour ago by the University that there’s only a metre to go until it spills out of the eastern gap of Meradalir. This was accompanied by a couple of photos showing how the lava is bulldozing the soft ground at the edge. (On mobile so cannot link to photos, sorry)

  34. Anyone here a Youtube expert? I’m having problems watching the RUV Langholl stream now. It keeps pausing briefly by itself and glitching with colored squares and other nonsense. It’s acting like it’s under bandwidth pressure, but I just double checked and no other apps on my machines here are using excessive bandwidth (the obvious suspect was something downloading a big update in the background). Reloading the page didn’t fix it either. What would cause these playback issues that a) would not be fixed by a page reload and b) is not bandwidth-starvation? And how do I go about putting it back to normal?

    • While I was writing that it paused itself again and this time it won’t unpause itself and I can’t seem to unpause it manually.


      • It unpaused itself eventually but also zoomed out by a sizable factor. How do I get it zoomed back in? I want a decent view of the vents and the lava pond, not a screen full of mostly rocks with a tiny eruption in the distance. What the hell is going on here?

        • And now it’s paused again!

          I want it back the way it was 30 minutes ago. How do I make that happen?

          • It had poor reception for awhile. Probably nothing to do with you, but an issue with the signal at the camera. These cameras work on battery power which can run low, and use mobile signals which can be weak. And if any remote steering is done, there may not be enough bandwidth and/or power to do everything at once. Patience – it will come back (as will the rain and fog). And we don’t pay for these cameras – the costs are born by others

        • It’s probably either RUV or the camera having some trouble at the moment. The other RUV cam is working still.

        • Why is the RUV camera staying zoomed out? We have no good close-up frontal view of the vent right now.

        • Repost: first attempt just disappeared without a trace.

          Why is the RUV camera staying zoomed out? We have no good close-up frontal view of the vent right now.

      • Consider that it might not be your computer. There is an alert in the RUV display stating “not enough power for both camera and pan tilt motors”. These cameras operate on solar power, and it has been foggy there for days.

Comments are closed.