Volcanic Poker

I’ve never played poker but I already know that I’d be terrible at it. I’m good at reading people but terrible at keeping my mouth shut when I am excited. I’m the type of guy to scream “I’ve got a royal flush!” if I were to get one. A royal flush, consisting of a King, Queen, Jack, and a 10 is the best possible hand in poker but it seldom happens. Like the world of poker, the world of volcanoes is chaotic and driven by chance. There could be several decades without a major eruption, or a major eruption per decade for several decades. A good example of a volcanic royal flush would be the 1780-1820 volcanic cluster, in which the infamous Laki eruption (Q), the 1808 mystery eruption (J), and the great Tambora eruption (K) rocked the world. Other examples would be the Sixth Century volcanic cluster consisting of UE 535 (Q), UE 540 (K), and UE 574 (J) and the 10th-century cluster of Eldja (K), Paektu (Q), and Ceborocu (J). As dramatic as it sounds, the chances of a rapid succession of large eruptions aren’t that slim, most centuries see around 3 or 4 VEI 6 so every decade has around a 30-40% chance of seeing a VEI 6+ eruptions. So every 40 years there’s more than a 1 in 81 chance of seeing a royal flush. Still more likely than seeing a VEI 8 eruption. One could only imagine the damage such a cluster would do nowadays but I’ve already written about a volcanic apocalypse so that won’t be our point of discussion. Since there is a relatively decent chance (in comparison to other Global threats) that the world could see a volcanic flush, let’s play some bets. Chances are that the next big eruptions of the century are building up right now, some could be ready to go in months, some in years, and some won’t be ready for decades or even centuries. It’s anyone’s game and while intelligence plays a role, it is impossible to know with any certainty which volcano is actually going to deliver at this stage.


I am dying to hear your hands and as an act of courtesy in this game, I’ll reveal mine first. What better way to start than with King? I’ve thought about the role of King and only one volcano should be assigned the role as it has no major detractors to its chances of producing a major eruption. Trust me, I’ve tried to think of some because I wanted another volcano to take the role of King but there was scant competition. The volcano needs no introduction, King is assigned to the extremely impressive and terrifying, the currently erupting Ioto or Iwojima depending on your naming preferences. I know this isn’t a very original choice for N.1 as this volcano is ranked number 1 on the famous NDVP, but some things aren’t really disputable. There’s only one other volcano that I can think of that seriously challenges Ioto for the role of king. As far as we know Iwo-jima is the fastest-inflating volcano on the planet, rising 50 meters since 1779 with the past 10 years seeing over 10 meters of uplift!

Shifts in horizontal deformation have also been noted. The X086 station has completely changed from west to east over the last 5 years, while the other station’s westward movement accelerated. An interesting development but I don’t know the cause behind it.. The volcano has been resurging for 700 years now and only now is starting to produce magmatic eruptions. While previous explosions (indicated by the numbers on the map) were phreatic, the 2023 eruption produced a new cone.

Iwo-Jima had 25 confirmed (phreatic) eruption between 1890 and 2010. The took place at locations 1 to 10 on the map – most were at location 7. The locations follow a (very) approximate circle, indicative of a ring fault, surrounding the resurgent done of Motoyama (number 5 on the map) which is the apparent centre of inflation. In 2012 an earthquake swarm indicated an acceleration of events. This was followed by a series of 23 eruptions over the following few years, most at location 1. The large event of October-December 2023 build a new island at location 10. The movement of site X086 to the north-northwest, directly away from the 2023 eruption centre, suggest that the magma had been building around this area since at least 2016. After the 2023 eruption, the horizontal movement changed and became more easterly. It seems likely that the movement is due to a continuing inflation of a deep reservoir underneath the centre of the island and a growing shallow reservoir on the southern rim, where the pressure from the latter relaxed after the 2023 eruption. Station 0605 is moving rapidly southwest, 0604 is moving northeast and X086 is also moving northeast. The next eruption could be near location 1 on the map.

The volcanic island is the only surface representation of a large 9 km wide caldera that was formed around 100,000 years ago with other large eruptions taking place since then. The inflation is being caused by an extremely strong persistent deep magmatic intrusion, the best kind of intrusion for large eruptions. The magma chamber is likely as molten as you can get and could have an unstable mixture of Trachyandesite, Trachydacite, and Basalt.

The extreme resurgence in conjunction with the first magmatic eruption in at least 1,300 years should raise some brows. The last 100% confirmed magmatic eruption was dated around 850 B.C so this could be the first true eruption in almost 2,900 years. This terrifying volcano did not produce a terrifying eruption. We got a relatively peaceful island-expanding eruption, and it’s completely possible that this type of eruption is all the volcano will do in the foreseeable future. Even the baddest of volcanoes produce harmless eruptions. The question is are things going to stay harmless? Don’t know but that doesn’t mean we can’t discuss the current situation! The last eruption was small and persistent so I can think we can approximate some facts with this. Whatever magma is erupting now clearly is not very volatile otherwise we’d be looking at a more visually spectacular eruption. No major swarm or shift in deformation preceded this eruption so nothing big has broken yet. I think this eruption is primarily fed by less volatile magma from its shallow system that is being destabilized by the intrusion.

The chances of a large eruption depend on how exactly the intrusion is influencing the shallow system. There are two solutions in my opinion, either large amounts of heat and gas from the deep chamber but no or little magma has reached the shallow system causing a persistent small eruption or magma from the deep chamber has entered the shallow system and is slowly forcing the less volatile magma out of the system. With Solution N.1, a large eruption is less likely since a small amount of magma would be active while with Solution N.2, a large eruption would be more likely with more quality magma being on the way to the surface from a large body of magma.  I think the lack of strong seismic activity gives more credence to the former but the latter solution is still completely possible.

Another extremely important question is how big of a role will water play in the coming months to potential years. In comparison with the eruptions that preceded the Hunga-Tonga Explosion, the previous eruptions were not big enough to react to seawater. The factors that will decide this volcano’s future will be discreet and could be hard to track. So before I talk about the volcano, let’s just remember that it is possible that things won’t escalate and the volcano will only produce fun eye candy. We also have to remember that this volcano is nothing to be trifled with. This volcano is capable of producing a violent eruption like Tonga or Krakatoa. In fact, I think it has more destructive potential than both. Unlike Krakatoa, the volcano isn’t surrounded by a shallow strait but by deep water, and unlike Tonga, there is a strong chance of a vent that won’t be smothered by water since more of the island is exposed to the surface. The volcano is way bigger than Krakatoa and Tonga standing 1.5- 2 km high and 40 km wide and it is plausible that this volcano could peak at VEI 7 and not a 6.

Obviously, if the volcano does decide that it wants to be in our history books, the biggest concern will be the tsunami and volcanic winter and since it would be folly to try and anticipate the sulfur budget of an eruption like this, let’s talk about the tsunami since we could at least crunch some numbers. The Hunga Tonga eruption crushed the idea that volcanic eruptions couldn’t produce long-distance tsunamis and gave us some new insights into how these eruptions work. Please watch these incredible videos on the Tonga and Krakatoa Tsunamis, All credit goes to Ingnomar200.

The depth of water surrounding Ioto is similar to that of the water that surrounds Tonga, almost perfect conditions for comparison. There are 3 major causes for volcanic tsunamis: Ignimbrite emplacement through column collapse, large explosions, and landslides. Unfortunately, Ioto looks capable of doing all 3 and to get an idea of how big the tsunamis could get, we’ll be considering 3 scenarios. Scenario 1 (Low-end VEI 6 akin to Hunga Tonga), Scenario 2 (Mid-end VEI 6 akin to Krakatoa), and Scenario 3 (An extremely explosive low-end VEI 7 with 40 km3 DRE of magma). If the blast was the main proponent of the volcanic tsunami for S1 then it would be identical to the Tonga tsunami (obviously). In this case, the Ogasawara islands would see the largest run-up probably maxing at 45 m and the sparsely populated Bonin Islands and Izu Islands would likely see much smaller but still significant wave heights. Mainland Asia and Japan would see much smaller tsunamis in the range of 1-5 m. The Tonga Tsunami was initially much larger than earthquake-driven tsunamis at around 90 m but degenerated in height MUCH quicker. The Tonga Tsunami had the same or just a little less energy than the Tohoku Tsunami, around 3.0e+15 J or 717 kilotons of TNT.

A column collapse has way more energy than even the largest volcanic explosions. A low-end VEI 6 could produce 1-2 km3 (DRE) ignimbrite through column collapse. Using the potential energy formula, I believe we can get a rough idea of how energetic these events are. 

PE grav.=m×h×g

Using 1 km3 of magma for this example, we get a mass of 2.5 trillion kg, for height, we will just 30 km since the mass won’t be evenly distributed across a 50-60 km high ash cloud. We get the value of 7.355e+17 joules or 175.8 megatons worth of energy. A lot of that energy is going to be lost in the atmosphere due to wind resistance and other factors so only a half or even less would make it to the surface. Assuming that a third of the energy makes it to the surface, and only 5% of that makes it into the tsunami, we get a total tsunami energy of 1.213e+16 J or 2.9 megatons (4 times more than the Tonga tsunami).

The Issue with PDC tsunamis is that they need to happen in Goldilocks conditions to be effective. The Column collapse has to be from a super-explosive eruption not just your run-of-the-mill eruption. The volcano needs to be high enough above the water so that the vent doesn’t get smothered with water but not too high so that the volcano absorbs most of the energy from the collapse. Needless to say, there are not a lot of volcanoes like this.

If Ioto decides to do something a bit larger akin to Krakatoa, then we’ll start to see some problems. Recency bias for Hunga Tonga aside, Krakatoa was significantly worse in all areas. The total explosive energy for Hunga Tonga was 65 megatons, while Krakatoa was worth 200 megatons. Krakatoa was bigger and badder than Tonga was. The eruption taking place in the shallow Sunda Strait likely limited its range. If we see a blast-generated tsunami for S2, we could see a tsunami 3 times larger than the Tonga Tsunami, and Mainland Asia could see run-up heights ranging from 5-15m. A PDC-generated Tsunami would be even worse, with 11.6 megatons worth of energy. The eruption for S3 would be 2.5x larger and more energetic than the Krakatoa eruption, so the potential tsunami energies would be scaled accordingly. This gives us 5.4 and 29 megatons for both potential blast-generated and PDC-generated tsunamis with Mainland Asia receiving minimal run-up heights of 12.5-37.5 m  with the potential for significantly larger waves. A landslide tsunami could also be on the cards with how massive the volcano is and the possibility of the deformation destabilizing the structure of the edifice but there is no study into landslide possibilities at this volcano so I won’t even attempt to give a simulation. Ioto has no major detractors to the potential of a major eruption and has scary tsunami potential. It is by far the best volcano to take the name of King.


“Dormant volcano awakens” headlines always get my attention but piss me off at the same time Just because a volcano is undergoing intrusion doesn’t mean it’s going to erupt, in fact, it doesn’t even mean that an eruption is likely. It’s fun to talk about volcanoes like Laguna Del Maule, Uturunucu, Kikai, and other resurgent calderas but nothing suggests that a major eruption is likely over the next century. Caldera volcanoes spend most of their time building magma and not doing anything so the behavior we see at these volcanoes is completely normal and isn’t worthy of the title of queen. One long-thought dormant volcano, Cerro Negro De Mayasquer or Chiles-Cerro Negro is not going through these normal motions and is looking scarier as the years roll on. I’ve already written too many articles so please read my previous piece on this volcano if you want its history. I will only be talking about the volcano’s current activity and its implications in this piece

The most recent swarm was without a doubt the most chaotic of the 5 swarms with 1 monthly pulse of high quake activity that lasts for a week before dropping back down to low levels, rinse, and repeat for four months. I initially thought that this swarm was the result of Hydro-thermal disturbances but this is definitely not the case. The official cause for the swarm was “Complex interaction between the faults, magmatic, and hydrothermal system.” but I completely disagree. Observations of the Hydrothermal system showed no significant disruptions and I have not seen a single tectonic earthquake take place at the volcano either. Inflation accelerated rapidly, going from 0.8 cm/month in July to 2 cm/month in October and reaching 5 cm/month in November. These facts don’t support a tectonic or hydrothermal origin behind the most recent swarm.

While uplift abruptly ended in December another development has caught my eye. After 18 months of silence, the inclinometers are starting to move at a pretty quick pace with peak speeds around 8 µrad/day so far. Since December, Cumbal has experienced a significant uptick in seismic activity. Cumbal’s seismic activity is caused by the hydrothermal system which is being destabilized by stress on the tectonic faults. A similar situation preceded the 2021 quiet period, and the volcano has seen weaker seismic activity over the several weeks. So I wouldn’t be surprised to see a few months or even a year go by without a major swarm. However, shifts in the Inclinometer and a seismic swarm at Cumbal all point to potentially significant stress on the regional fault system which is almost definitely somehow related to Chiles-Cerro Negro.

We are starting to see persistent VLP earthquakes at depths ranging from 1-2 km. (The reports don’t specify if it’s 1-2 km below sea level or the summit!) This is likely related to the movement of magma. During the swarms of 2022-2023, magma ascended at least 2 km, and depending on where the magma is now, the volcano may need just a few more big pushes to erupt. If the magma is 1-2 km below sea level, it might take 3 more seismic crises of similar magnitude to bring an eruption, and if the magma is 2 km below the summit just one more swarm could be enough.

Any lurkers in the comment section will remember the “Great Dike Debacle.” I brought up the existence of a dike intrusion below the volcano but the presentation was poorly written and the parameters brought confusion.

Tallis, think I figured out your dike mystery. By width they mean the height of the dike. The volume change they give equals the length X ‘width’ X opening. So it can’t be horizontal width, rather vertical.

Which makes much more sense than an 800m wide dike anyway. I’m guessing it is so insanely seismic for the same reason Fagradalsfjall was, not being active for many thousands of years so very cold, hard rock. But trying to interpret the challenging language, it sounds like they don’t think the structure was created this year. It just added 0.04km^3 over this year by widening 0.24m. And has been growing for at least 9 years. So large structure still, at least a few tenths of a km^3.

600k over those 9 years versus Fagradalsfjall’s 40k before erupting, though Fagradalsfjall skewed larger with more ≥4.5 magnitude quakes


54 km3 (assuming that the width is given horizontally rather than perpendicular to the dike). Which of course is completely unrealistic. A dike can be 8 meter (a very large one). Not 800 meters. That would require the rock on either side of the dike to be pushed by several hunderd meters. If you meant a width of 8.01 meters, divide the volume by 100


The dike isn’t 54 km3, it probably delivers around 0.004 km3/yr of magma to the shallow chamber which is not a lot of magma. I say probably because Dr. Mothes, (Chief of the IGEPN) takes the numbers with a grain of salt. It seems impossible, could such a small intrusion cause so much instability?

Volume Changes are very uncertain, going from 3 million to 30 million m3 which is not a good constraint whatsoever.” Patricia Mothes

Studies have shown that current inflation is the result of the magma flowing into a large shallow magma chamber. The last study located the chamber in a region with width of 15 km and with a height of 8 km yielding a maximum volume of 1,413 km3 of magma but this isn’t the only magma body beneath the volcano. During the final years of 2020, 500 deep long-period earthquakes shook the volcano with distance extending up to 5 km northwest of the Cerro Negro cone or 10 km away from the uplift. Keep in mind that inflation didn’t change at all when this happened so these quakes weren’t the result of the intrusion. These quakes were likely the result of a magma movement within a deeper chamber.

In 2022, there was another wave of deep long-period (30km+) earthquakes that shallowed to 4 km below the summit in one month. This was clearly the result of rapid magma ascent and as the magma shallowed, the uplift at the volcano intensified. The uplift at this volcano has been chaotic. Going from 20 cm in a few months in 2014 to almost zero in the later portion of the same year to a steady 3-5 cm a year from 2015-2020, back to zero in 2021, and finally going off/on for 2022-2023 juggling between 5 cm/month and zero. That is not indicative of a typical magma intrusion, the current unrest is likely being caused by magma from the deeper chamber moving into the shallow chamber. The extreme instability in deformation could be explained by the shallow chamber receiving a fluctuating supply of magma. However, if the chamber briefly loses supply and stops inflating from time to time, we should still see uplift from the deeper chamber if it was under intrusion which we don’t. Looking back at the start of the first swarm in 2013 caused by the supposed magma intrusion, it was highly erratic and didn’t have the same behavior as other volcanoes under the same circumstances. The hydrothermal system has only slightly warmed in the past 11 years. These circumstances lead me to question if the volcano is even under intrusion in the first place. The Wah Wah Springs eruption was not preceded by an intrusion, so volcanoes can erupt without intrusion.

This volcano is a mysterious enigma! The IGEPN doesn’t know why seismic activity is juggling between Potrerillos-Chalpatan and CCN and I don’t either! Inflation has flipped on/off and changed intensities 7 times in the last 10 years. Simple questions don’t have any concrete answers, How much magma is going into the system? We don’t know. Why is the seismic activity and inflation so erratic? We don’t know. How big is the system? We don’t know! For me two facts are certain, magma is rising and this isn’t the volcano’s first rodeo

In 1868, 2 earthquakes rocked Northern Ecuador, killing and injuring 70,000 people. One of the quakes was 6.3 was located in the El Angel region, 20 km away from the Chiles volcano which is within range of the volcano’s influence. The other quake was 50 km away and might not be linked to the volcano. I can’t definitively prove these quakes were related to unrest at the volcano but the reality is that this volcano has been restless for years, likely centuries. If the volcano was as extinct as some thought it was, the unrest wouldn’t have escalated so quickly, and just because the volcano was quiet when it was first recognized doesn’t mean it’s been quiet since its last eruption. It is impossible for < 1x10^7 m3 intrusion to bring a 1,400+ km3 dormant plugged chamber this close to erupting after just 11 years. Much larger intrusions have hit more active volcanoes for longer and have never gotten close to where we are with Chiles-Cerro Negro.

The only thing keeping this thing from erupting is one plug, one plug that’s been around longer than Human civilization, it might last another 10,000 years or might not last another 9 months. It depends on what exactly is causing the extraordinary escalations at this volcano. As someone who’s been tracking this volcano for almost 10 years now, this volcano has done nothing but escalate and unless the unrest stops soon, things will only continue to escalate.


For Jack, I going to cheat a little. I won’t be assigning Jack to a single volcano, instead an entire region will take the role. The most volcanically active and interesting region of this century so far, Iceland will take the role of Jack.  More specifically, Katla, Grimsvotn, Hekla, and Oraefajokull. All 4 of these volcanoes have been under prolonged unrest, and have a history of producing big sulfur-rich eruptions. I’ll rank the volcanoes based on how much faith I have in them to deliver a large eruption, and I will start with the one I have the least faith in, Oraefajokull. It is famous for being the most voluminous and highest volcano in Iceland and infamous for it’s massive deadly VEI 6 (Icelandic VEI 5) eruption in 1362.  This volcano has been under magma intrusion for the past 7 years causing inflation and elevated seismic activity. This an interesting volcano but the unrest is as boring as you could get. Less than 10 million m3 enters this system yearly, with peak inflation at about 4 cm/year. Not very impressive, the volcano is the least active of the 4 while undergoing the least intense unrest. It looks like this will be either your typical harmless magma intrusion or slow charge before its future eruption. 

My favorite Icelandic volcano is Katla for pretty obvious reasons. It is one of the most prolific explosive volcanoes producing 4 Icelandic VEI 5s and a minimum of 12 Icelandic VEI 4s in the last 1100 years, On top of this it produced the largest effusive eruption in the last 8,600 years. Capable of fantastic felsic eruptions or massive mafic blasts, this volcano is a beast among beasts. Ever since Iceland was settled, Katla has etched its fearsome potential into the skulls of the people of Iceland. However, even the baddest of volcanoes need breaks and that’s exactly what seems to be what’s happening now. The volcano is experiencing the longest period of dormancy ever recorded and uplift at the volcano is weak but seismic activity is consistently high. In fact, there is been an uptrend in seismic activity in the past few years with consistent deep quakes representative of magma movement. Despite being the most infamous volcano in Iceland, it is arguably the most mysterious.

In my opinion, the volcano is either undergoing a persistent small intrusion or has a high yearly supply. Given this is Katla we’re talking about I am inclined to believe the latter. I believe the current activity is being caused by the hydro-thermal and/or the largish shallow magma chamber (a little over 10 km3) There is nothing currently going on at the volcano to suggest a large eruption is on the cards in the next few years. This could easily change if the volcano gets stronger intrusion and a long repose time for Katla could easily bolster the size of its next eruption but until that happens, its chances are low.

Hekla is responsible for around 10% of Iceland’s tephra in the last 1000 years, known for it’s youth and unpredictability. Hekla is undoubtedly one to watch. For the last 20 years, it’s been inflating relatively quickly and has long since recuperated the magma it lost in its 2000 eruption. Hekla has a bad habit of erupting large amounts of the magma it builds during dormancy so a long dormancy will definitely give way to large eruption. Hekla has a decent shot at producing a VEI 4 in the next decade. Unfortunately, we have no idea how close it is to producing an eruption, and the volcano is not known for giving warning signs. This means that it could spend 100 years sleeping or erupt next week. Amongst the 4 volcanoes mentioned, Hekla has the lowest high in terms of its eruption size. I think Hekla has a greater chance of erupting over the next few years than Katla but I don’t think it would produce a Katla-sized eruption without a longer recharge period.

I’ve had my fair share of disagreements and debates on this blog but I’ve usually understood the alternative angle. I understand the skepticism behind CCN’s “dike” and my opinion on volcanic tsunamis but there is one debate that I don’t understand the opposing views argument. If I were to bet on 1 Icelandic volcano for a large eruption in the next few years, I’d put 90% of my money on Grimsvotn

Grimsvotn seems to be on a roll over the last 240 years, producing 2 VEI 4s after giving us the massive Laki eruption. You’d think that after so many large eruptions, it’d be ready to sleep but on the contrary, the volcano is doing better than ever. I’ve heard some say that the 2011 almost VEI 5 eruption was a 1 in 1000 year event for Grimsotn and the climax of the multi-decadal volcano uptick and as such the volcano will need more time to recover. That is after all the average pattern for a volcano such as Grimsvotn but the truth lies in the data and the data doesn’t support this argument in the slightest. GPS data shows that the rate of inflation at Grimsvotn pre-2011 has been maintained post-2011 with no downtrend noted. The multi-decadal uptick clearly hasn’t ended. There was around 30 cm of uplift preceding the 2011 eruption and currently uplift has reached 80 cm. The volcano has smashed preceding levels of Cumulative Seismic Moment, and the volcano’s hydrothermal systems have been heated to the extreme once again surpassing the values of the 2011 eruption. 

 None of this points to a downturn in activity that would give way to a small eruption. More magma means more pressure, more pressure usually means a bigger eruption. Let us not forget that the magma that erupted in 2011 was very primitive and hot and there is likely 2.5x more of it than there was in 2011. Of course, the size of the eruption will depend on more discreet mechanisms and it’s possible that we’ll see a smaller VEI 3. A VEI 3 would only be a hiccup in terms of the current supply and not relieve the volcano enough to deny a larger eruption.. The volcano recovered the magma it lost in its 2011 eruption after 4 years. Think about it for a sec, the 2011 eruption produced 0.8 km3 of tephra or around 0.2 km3 of magma DRE and Grimsvotn got that magma back in 4 years. This means that this volcano has been getting a VEI 4s worth of magma per year! A VEI 3 is NOTHING to the volcano now. It is also possible that the dormant magma from the chamber has been activated by such a high rate of magmatic influx. This isn’t Ioto or Chiles-Cerro Negro where these volcanoes have not developed their shallow magma systems before they erupt big. Grimsvotn likely already has a strong shallow system due to its frequent activity. I am not saying that the next eruption is going to be like Laki but I wouldn’t doubt a VEI 5.

The volcano is so active that an eruption is pretty much guaranteed in the decade so there is almost no argument for it remaining dormant for 15+ years. The volcano has more magma, more pressure, more heat, and likely has more strain than the last eruption. So a larger eruption is not only possible it seems probable.  I’ve noticed that there’s been a significant seismic uptick 16 km to the NW of Skafatell along with some decent inflation with minimum values of 4 cm/year. The inflation looks to have started in 2019 with the seismic activity. I don’t know if this related to Grimsvotn but it caught my eye. 


I believe I got a good trio with Ioto(K), Chiles-Cerro Negro( Q) and Grimsvotn (J). I think Chiles-Cerro Negro has the potential to produce the largest eruption of the 3 while Grimsvotn has the highest chance of producing a large eruption. Iwo-jima has a higher chance of producing a large eruption than Chiles-Cerro negro and can produce a significantly larger than Grimsvotn, just another reason why it takes the role of king. 

Of course, we’re missing a face card, a card that seldom shows itself but its value is fluid and can even overtake the king in terms of worth. The Joker Card.

When you gamble, the more risky bet yields the most rewards and forecasting follows similar rules. No one is impressed by one who goes with the river or the consensus, people find rebels and the insane more fascinating than the average worker and soldier.

We can speculate on potential volcanoes but the reality is that a vast majority of volcanoes are unmonitored and not studied. Our past experiences with large eruptions do not apply to every volcano. Some volcanoes don’t awaken with an ultra-dramatic swarm or a high inflation, some volcanoes awaken very slowly, and after the slow process is complete we see signs of an eruption. We’d assume that the volcano has just awoken while the climax could be just a few weeks to months away. It is possible that Ioto won’t produce an explosive eruption, Cerro Negro would opt for a large felsic lava flow, and Grimsvotn could do a series of VEI 4s and 3s to relieve itself. All the while another volcano gives us our large eruption. Anyone who’d say a volcano that looks quiet and unassuming has the potential to produce large eruptions would likely be dismissed but they could be right! If their forecasts were verified, they’d solidify themselves as legends. It’d be a risky bet though. A volcano catching the world by surprise with a major VEI 6+ is unlikely but not impossible. For the role of Joker, I would like to know your pick for a volcano that looks to be unassuming and harmless and that you believe to have the potential to generate a large eruption in the near future. The role of Joker could go to a slew of volcanoes, some that I am not even aware exist! I think Tatun, Udina, and Laacher See are good contenders for the role of Joker but that’s a story for another time…

To be continued?


http://geodesy.unr.edu/NGLStationPages/stations/X086.sta [geodesy.unr.edu]

https://fringe2023.esa.int/iframe-agenda/files/presentation-488.pdf [fringe2023.esa.int]

199 thoughts on “Volcanic Poker

  1. Albert, How big do you reckon the shallow chamber at Ioto is? I’ve done tons of research and haven’t got a clue.

    • Not huge, I expect. As a high estimate, assume 1000 years of feeding at a rate of 0.01 km3 per year which gives 10km3. Now divide by 10 to get a low estimate

      • That’s assuming that there wasn’t a pre-existing reservoir beforehand. Wish there were more definite parameters It’s so frustrating that the world’s fastest uplifting volcano and the world’s 2nd most seismically active volcano have such little study dedicated to them

        • Not sure why we are assuming 1000 years of feeding? Its been longer than that since last caldera eruption and seems plausible started inflating before Suribachiya stopped. I can get up to close to 20km^2 extrapolating back and assuming it started as a flat caldera floor and Motoyama had significant erosion when it first tried to emerge (very safe bet given Chidorigahara exists. May be even higher than that since we know from Suribachiya that the area inflating is *larger* than the caldera. That is of course much slower than Motoyama, but is huge for volume estimates since that is a much larger area in km^2 than Motoyama. Most of Ioto’s inflation volumewise is still going to be below sea level. Would be really nice if people did detailed surveys sometimes…

          Of course though some of that will be deeper chamber, not shallower one I assume. So the shallow chamber may be rather less that full 20 km^3 or whatever.

          I wouldn’t be at all surprised if there have been other magmatic eruptions since Suribachiya stopped. But it is at least the first one in over 100 years in a system that seems very hard to imagine making it more than a couple thousand more. Given how much it is inflating and that, not that implausible it has a 10% chance of redistributing itself in the coming years. Which for a single volcano for probability of a VEI 6-7 is freaking huge. Though I suppose chance it goes Nishoshima-style and just starts putting out huge volumes at some point non-violently. I am worried how much water is probably trapped in that thick tuft layer that seems to exist a ways down given Hunga Tonga.

  2. Given Iwo Jima (etc)’s big ring-fault and adjacent deep water, I must wonder if has the makings of a Santorini / Thera event: Big, bad, perhaps one for the record books…

    Which ways do Iwo Jima’s seasonal winds blow ?
    Might even get a storm-induced sector slump, triggering a Mt St Helens-style lateral blast.
    IMHO, that would be very bad for the island, but some-what spare the stratosphere…

    FWIW, my second-cousins in Mexico City are, um, looking over their shoulders at ‘Big Poppa’, which is currently having yet-another noisome fit of the sneezes. Even if a ‘significant’ eruption’s ash blows *away* from mega-city, the likely quakes and lahars would be a grim combination…

    • It has the potential but it all depends on the current condition of the shallow system. Popocatépetl is one to watch but the current activity doesn’t signal anything scary(at the moment)

    • Air quality in Mexico City is pretty bad even without a volcanic eruption.
      The worst I have ever been in, but never been to Delhi.

      They have an inversion layer like Los Angeles but without the strict emissions regulations.

  3. ‘Icelandic VEI 4’ is not really a thing, Grims 2011 didnt get over 1 km3 of tephra so its just a 4. 7 days to erupt it also isnt really that intense, even if it was mostly in 2 days that is still only about 0.1 km3 a day. Kelud in 2014 erupted a similar volume as Grimsvotn did in 2011 but in a couple hours, and St Helens did a VEI 5 in a few minutes. Most likely the 2011 eruption would have been mostly or entirely effusive without the ice, Mauna Loa and Sierra Negra have both done completely effusive eruptions of similar intensity and volume.

    The same thing at Katla, all of its eruptions bigger than a low 4 lasted a long time, its VEI 5s in the 18th century both lasted for months each. That isnt to say its eruptions are not powerful but I think putting them up there in the same league as a probable VEI 7 progenitor is quite the leap, not when there are other large subduction calderas of similar dimensions but with greatly enhanced volatility. Yasur in particular is very worrying,its an open vent with a lava lake yet still resurgent and rapidly so.

    • Interestingly, Shawn Willsey did an interview with Professor Þórðarson who seems to suggest that volcano-ice interaction only makes ash finer and doesn’t influence explosivity.

      • I watched that interview, very interesting. I interpreted it as that the water interaction doesnt increase the eruption intensity it does increase how powerful the explosions are (so finer ash eg)

        2011 Grimsvotn eruption lasted a week but mostly 2 days of intense activity. It sounds a lot but it ends up to be a maximum of 100 million m3/day, which is about 1100 m3/s. So probably 1500 m3/s peak. That would be intense for an effusive eruption but it has happened before, Mauna Loa in 1950 erupted 0.3 km3 of lava in 1 day, and most Mauna Loa eruptions go into the thousands of m3/s during the early fissure propagation stage but getting exact volumes for that is hard. Magma composition of Grimsvotn 2011 is tholeiitic basalt that is relatively evolved at 5% MgO which is low compared to Bardarbunga (6-8%) and recent lava at Reykjanes (9%), and especially Hawaii which is typically over 7 and has been as high as 16%. It is about the same MgO as Askja. Askja is probably very good as a comparison to Grimsvotn without ice, and Askja doesnt explode unless there is a caldera collapse and silicic magma which Grimsvotn doesnt have.

        I would believe that Katla explosive eruptions are more magmatic, but Katlas biggest explosive eruptions were much lower intensity too. 1755 erupted 1.5 km3 of tephra, probably 0.5 km3 DRE, but in 3 months. So only about 60 m3/s eruption rate DRE.

        • The large eruptions of Katla have an episodic nature like Eyajafokull so days or weeks can pass without an episode. Using averages for magma output for such eruptions is impractical.

          • Can you send me a source for that, I havent been able to find much info about Katla and its eruptions apart from Eldgja and stuff written on this site…

          • This study has some accounts of the eruption. Google

    • Super curious as to your thoughts on Yasur as I don’t know much about it. Seems like it’s been in constant eruption for potentially ~800 years, but assuming based on your comment that it has some caldera action in the past that could be a worry in the near future?

      • It is a caldera already, 4 km wide and has uplifted 20 meters in the last century. The original caldera formed in an andesitic ignimbrite eruption, which erupted hot andesite spatter and probably behaved a lot like Hunga Tonga Hunga Ha’apai though was not as big.
        The original eruptions of Yasur itself seem to have been more powerful and less continuous starting about 1500 years ago, and became continuous about 800 years ago up to today. But there are no lava flows in that time at least that I am aware of so it never really erupted that much more just an open vent. It going caldera might actually start with it having large effusive fissure eruptions from the ring faults as presumably the thpusand years of open venting has made the magma relatively gas poor, before destabilizing more explosively as the collapse self sustains. But that is all hypothetical

      • Yasur is an interesting case definitely worth an article. It’s clearly building pressure and if the current eruptions are not doing a good job of relieving it in the long-term. One weakness is that a significant amount of magma has degassed without erupting and that would limit it’s chances of producing a large eruption in the near future

  4. I just checked google maps and the GPS station looks about 25-27 feet off from where Google thinks it is. 24°46’48.0″N 141°18’07.2″E. The station appears to have moved ESE around the 110-115 deg compass line or so. This is evidence of land movement. I have seen similar things in CA where Google maps apparently has nearly current satellite pixel geolocations and older archived maps which are mostly used for geolocations have not kept track of movement.

  5. Really interesting! Looking forward to a part two.

    One little niggle.. A Poker hand has 5 cards, and a royal stright flush needs an Ace at the top. (AKQJ10) It’s even in the picture at the top !

      • Although our Iwo Jima does have a 300m thick tuft layer from three big eruptions ago. If it is same thickness over entire suspected caldera, that is ~25km^3 falling back into the caldera, likely a VEI 7. I suspect the reason rim of ‘caldera’ is rather broken is at least 200m of material and rather more of inflation post that eruption, biased toward center so only highest parts of rim survive. Should be pretty clear on good density imaging if true though… Really would be nice if Iwo Jima got some detailed attention.

        With Iwo Jima I do wonder if 600BC was just a precurser eruption, a-la Crater Lake. Its been averaging at lease close to 1km^3/century, quite possibly over in recent centuries (more like 5X that for past decade). Even for subduction zone volcano that is a lot. I wonder if that eruption happened from a surge of supply into somewhat stale magma. Result relatively small eruption, Albert or Carl suggested at one point VEI 5 range, though still enough to disappear an island then existing. Then starts to seal itself, inflates, probably like Sakurajima or Yasur starting even before Suribachiya stopped erupting.

    • That article is about the Kikai caldera. It has a small “new island” aka “iwo jima” in it.
      That’s why I prefer “Ioto” to refer to the WWII famous and famously expanding Iwo Jima.

      No I do not speak Japanese. I know maybe 50 words and some idea of the grammar.

  6. Sometimes I’ve noticed “dormant volcano awakens” (f.e. Kadovar 2018 near Papua New Guinea), but often it’s only kind of a Strombolian volcano that begins to erupt after long dormancy. How would an awakening of an awsome volcano look different to a Strombolian/Vulcanian volcano?

    Wasn’t Taal scheduled to do more dangerous eruptions after the first one 2020? It’s still a caldera volcano.

    Katla had an eruption 920, 20 years after the first Reykjanes Fires started at Krysuvik system. If it repeats this timetable, an eruption would by possible during the middle of the 21st century. I wondered a bit, why Katla didn’t follow Eyyjafjallajökull 2010 to erupt. There was some hydrothermal activity, but not a real eruption.

    • Maybe Eyjafjallajokull and Katla are overlapping at the magma source. Actually that whole area could be connected down in the mantle, the 20th century saw Katla be basically silent but Hekla has erupted much more than normal, where before that both would erupt about the same frequence of 1-2 times a century. Hekla though seems to erupt magma from a slightly different composition mantle, or contaminated with crust, maybe there is a continental fragment under it. Katla also has huge CO2 output despite basically 0 magma supply so evidently a lot of magma is down there.

      This patch of volcanoes is a bit of a weird bunch really. Hekla is a plate boundary volcano, Katla is an intraplate volcano with some rifting aspect and Eyjafjallajokull is just an intraplate volcano. But the magma is all the same, and different from Vatnajokull plume basalt. I would expect them to interact somehow. Maybe if Eyjafjallajokull didnt erupt only a decade after Hekla last did then Katla might have been induced too but it was not so. And the Katla eruptions concurrent with Eyjafjallajokull historically were not very big so maybe a bit of a dud really. Grims 2011 was probably rather more than a likely Katla eruption then would have been.

      • 1821-1823 Eyjafjallajökull and Katla did a “pair eruption” together. That’s why some scientists 2010 predicted that Katla would do this again. But maybe the 1821-1823 eruption of Eyja was different somehow to 2010. The Catalogue of Icelandic Volcanoes describes it as “The eruption of 1821-1823 lasted for about 14 months, but included long periods of little or no activity.” This sounds like a low intensity of this eruption.

        • Its probably more of a case of extrapolating too much from a small sample size than anything else. Eyjafjallajokull did erupt with Katla in 1823 but was erupting for 2 years already before that and it actually stopped 6 months before Katla started, and the Katla eruption was not really any bigger anyway at a VEI 3 and 1 month eruption. Eyja had a small eruption in 1612 while Katla had a large one. But Katla has erupted a lot more times than that without a neighbor getting involved. And there was a fissure eruption on Vatnafjoll next to Hekla in 1440 the same year as Katla did a VEI 4 but no one seems to want to claim a pattern for that one 🙂

          • If I’m right, the onset of the Middle Age’s Fires during 10th century was accompanied with eruptions on Snæfellsnes (SVB) and also the Katla/Eldgá eruptions. I’d also have an eye on WVZ for possible activity during Reykjanes Fires. I have the impression that the Reykjanes Fires are like a wave of activity in western Iceland that can easily spill over to other systems outside RVZ.

            From RVZ Fires to Fires the neighbouring systems shift activity between each other, so that our Fires may see different activity than the Middle Ages Fires. Last time the WVZ was quiet, but it’s possible that we get something on WVZ.

          • There was a news article about some quakes at Snaefellsness that were interpreted as the Ljosfjoll system waking up. This is the system that made the cones at Bifrost and Eldborg, so seems to do eruptions like the one in 2021 though maybe with tendancy to have higher fountains. So should be a tourist eruption 🙂
            Its a weird area, Holocene cones and Pleistocene hills sitting unconformably on middle Miocene eroded basalt. Although it isnt clear if this unconformity is actually real or just from heavy glacial erosion removing stuff older than the last glacial maximum. Nothing about to happen really soon though, but maybe in the 2030s

            There was also Hallmundahraun up on the northwest side of Langjokull that erupted in the 900s. Was a huge long lived shield eruption. There was a swarm of quakes near Skjaldbreidur south of Langjokull last year, turned into nothing but does make you wonder.

            But before either of these things happen I expect we will get many more eruptions at Reykjanes.

          • All the longterm dormant volcanoes of Iceland are difficult to predict. We have no scienitific live experience with them. The Middle Age’s RVZ Fires show, that during their activity Iceland’s volcanoes can do some unusual things. I think we should be prepared that Iceland is going to do eruptions on places where we haven’t got any since Vikings Age.

            Snaefellsness Volcanic Belt is a precedessor for RVZ. It is a “fossile” system that is not extinct yet like the Turtoise. It’s possible that a wave of volcanism on RVZ also activates the former generation.

            Hallmundarhraun (WVZ) on Langjökull’s flanks has a length of 50km, so nearly like the Socorro lava flow. It covered an area of 200 square kilometers and had a volume of 2-3 cubic kilometers. An eruption like this would come as a surprise, because it would happen in a longterm dormant area. It could indeed be one of the Queen effusive eruptions …

          • Snaefellsness actually isnt a fossil system, it was the former ridge but that went extinct a long time ago, the current volcanism is of different origin and composition, and started during the Pleistocene. More what I meant by the unconformity is if earlier interglacial lava or cones might have existed and were completely eroded away by the Holocene. Eruptions are not rare but happen over a wide area so resurfacing is very restricted.

            Hallmundahraun seems to actually be bigger than that, as much as 9 km3. It also is exposed as a pahoehoe field but it seems didnt start off that way, the Icelandic shields just like Pu’u O’o appear to start with intense fissure eruptions. It might be volumetrically minor only 10% or so but that might still mean beginning with a fissure eruption as large and intense as Holuhraun in the case of something as big as Hallmundahraun might be. Just Icelandic has a video about it I believe, with a story about the eruption as seen from afar.

            The shields probably draw from deep magma reservoirs abd maybe arent fairly associated to any central volcanoes. Maybe all of the central volcanoes are in fact just shields that became polygenetic. This deeper magma inyrusive conplex is basically a bigger version of what is happening at Svartsengi and much deeper. I think maybe Laki and Eldgja also erupted from this, though because those were huge rifts the magma flow was able to be much higher than a shield eruption and the style was very different as a result. Langjokull is also on a rift but it is much less active so probably cant crack open like Laki did, leading to short rifts that erupt slower (still quite fast) and wear out a wide vent as they decline,and eventually just end up erupting at the magma supply rate which could be about 5-10 m3/s during active periods if Svartsengi and Fagradalsfjall are a good guide.

            So basically if a shield starts it is going to be like Holuhraun but it doesnt stop… 🙂

  7. According to the GPS page on Vafri, all 3 closest Sites to the recent eruption, Svartsengi, Thorbjorn and Eldthorp are all now well above the previous eruption inflation levels. So it could be any day now for the eruption, even any hour. I will add the caveat that Svartsengi and Thorbjorn both exceded the previous inflation levels before erupting last time.

    • Svartsengi (or black belt according to some translations :P) is affected by the feeder to the dyke and Thorbjorn by the weight of all the rock beneath the sensor. Eldvorp is a bit away from the sill, with Skipstastahraun and HS02 being closer (especially HS02). They are both level with the last inflation, perhaps slightly higher. All of them are starting to level off, so it is probably days rather than weeks.

    • Is the Svartsengis system able to create a permanent vent with an open conduit for recurring eruptions?

      • Will be sort of up to what happens in the next eruption I think. The last eruption was in the same place as the one in December but a shorter fissure and probably less intrusion beyond the fissure too. Krafla during its 1984 eruption managed to create a singular vent, and at Svartsengi there is Arnarseturshraun which seems to be at least a relatively very short fissure compared to similar age Eldvorp and to what has happened just now.

        But I dont think the next eruption, and probably not for a few more after that at least, are going to be anything like what happened in 2021 or like Pu’u O’o and Mauna Ulu. Those were fed by more vertical magma systems where Sundhnjukur is at the edge of the sill. That is also true of Eldvorp too, only that sits on the other side of the sill complex. Illahraun and Arnarseturshraun actually erupted from a dike that went basically through the middle of the sill complex, presumably that meant it was more directly fed by the magma soyrce and also could continue to be fed after the initial high pressure stage. But then if we get potentially 12 or more eruptions of high intensity this year I would expect the magma path to get pretty worn in quite fast so really it js anyones vet still. I very much would like to see a lava geyser again but Pu’u O’o sent flows as far as14 km, a similar vent at Sundhnjukagigar would do some damage, and repeated eruptions would probably overwhelm the walls and likely fill in the natural topographic barrier protecting Grindavik.

        • A geographically fixed vent would make it easier to predict possible lava flows. It would be usefull to build appropriate lava dams and protect Grindavik and other settlements. As long as the fissure or lava vent location varies, it’s difficult to predict the behaviour of the dangerous first few hours of the next eruptions. The recent eruption showed, that the eruption rate is huge during the first hours, a lava flow is rapid running somewhere. It’s nearly impossible to react and to save any settlements in the path of the lava flow/flood.

          • If there is one thing about Pu’u O’o that can be learned it us that the vent actually can change and move a bit. Even after Pu’u O’o itself became firmly located it was not for another half year again that the vent didnt rupture or even turn into a curfain of fire again. And about 1/3 of all the high fountains had satellitic vents, 1986 was when it completely failed but it was basically on the verge of doing so as soon as the vent became significantly elevated above the original terrain. And likewise if Kupaianaha didnt stay open it is likely fountaining would have resumed as the vent was still narrow into 1987.
            All of this basically applied to Mauna Ulu too. And Mauna Ulu actually did return to high fountaining in 1974 as its elevation exceeded the elevation of Halemaumau, though not for long.

            Basically Svartsengi might evolve to erupt from a small area but its unlikely to turn into something like Fagradalsfjall 2021, the eruption rates are too high at the onset to avoid breaking open a bit. If the last eruption was coming from a single vent the fountain would probably be something like 1000 meters high 🙂 msybe not quite but many hundreds certainly.

            I guess we might get some answers in a few days.

    • SKSH seems to be right on top of the sill, VMOS too is over the bottom of it. Both with elevations now above that of the previous eruption. This system is pretty extraordinary in terms of recovery time.

    • Maybe premature. Lots of M1-2 size quakes in the same spot just prior to previous eruption.

        • Hopefully not through Kleifarvatn. Eldey, Brenninsteinfjoll and Hengill all candidates.

          Sundnukar looks like it going to erupt within 48 hrs.

          • Kleifarvatn would absolutely suck. Let’s hope not!

          • I’d assume that we should only expect Svartsengi, Fagradalsfjall and perhaps Eldey to erupt this year. The others still have 400 years to erupt during the RVZ Fires. They won’t blow up too dense temporally together.

        • I don’t remember seeing any 3+ quakes in the Krisuvik system before and coupled with some 2+ in the cluster, it could be a change.

        • Krysuvik as well as Reykjanestá/Eldey shake apparently during expansion of Svartsengi’s magmatic systems. It’s difficult to distinguish them from locally originating earthquakes.

    • Eldvorp ELDC (8 hr) ITRF14-detrended

      Using the North and East traces to predict next fissure eruption

      North and East Traces

      Dec 21.6 days
      Dec-Jan 26.4 days
      Jan-Feb 25.1 days
      Feb-now 19.5 days

      Assuming 25.5 days period, we have 6 days to go as of today Tue Feb 27th.

  8. 7.6 million cubic metres of lava has accumulated under Svartsengi, according to latest modelling. Previous eruptions show that the probability of a volcanic eruption increases when the volume of magma reaches eight to thirteen million cubic meters. If magma accumulation continues in the same way, the lower limit will be reached tomorrow. An eruption could begin at very short notice, and it is most likely that an eruption will occur in the area between Stóra-Scógfell and Hagafell.

    A new hazard map has been issued by IMO.

    Source: https://www.ruv.is/frettir/innlent/2024-02-26-aukin-haetta-a-eldgosi-405907

    • The Icelandic word “aukin”, translated to something with “to increase”, is linked to English “auction”. As they rise/increase their bids in an auction, is the risk for an eruption increasing now.

      The map predicts an eruption location in the area of January’s eruption. For Grindavik it would be better, if the eruptions move towards North or Northeast.

      • Auction comes from latin “augere” (to augment). And you’re right, “aukin” (in Swedish it’s “öka”) is related to this word. Apparently, there was none of that “augmenting” before we got ourselves christened up here in the north! 😀

      • Also, just as a tip for you fellow hobby etymologists out there:

        If you want to find the etymology of a word, basically any word, in any language, dead or alive, simply look it up on “wiktionary”. I do this by googling “blank wiktionary” and it takes me there. You can spend hours tracing random words back to Old French or Proto-Germanic. So much fun to be had!

        • I remember first being told a grouse lek and thinking it probably came from Scandinavian leker, to play. I learnt Norwegian partly by relating words to German or regional English words, once I learnt the pronunciation of letter combinations.

        • Wiktionary is a good tool, to discover the roots of words. Often the loaning of a word changes the meaning a bit. Words mirror their use and the world/time when they were needed.

  9. https://arstechnica.com/space/2024/02/final-images-of-ingenuity-reveal-an-entire-blade-broke-off-the-helicopter/

    Final images of Ingenuity reveal an entire blade broke off the helicopter

    Finding a missing blade

    The rover is now moving away from the helicopter and bound for other scientifically interesting vistas. After recently getting to within about 1,500 feet (450 meters) of Ingenuity, Perseverance likely will never be as close again. However, as it was moving away, the rover turned its SuperCam Remote Micro-Imager toward the helicopter for the final time. Those images, captured this weekend, were sent back to Earth on Sunday. A German design student, Simeon Schmauß, processed some of these images to form a mosaic showing the helicopter and its surroundings in Neretva Vallis, an ancient channel through which water once flowed.

    The new images are remarkable in that they reveal Ingenuity more clearly than before and show that one rotor blade was completely broken off. Additional sleuthing revealed that this blade lay about 15 meters away from Ingenuity on the red Martian sands, apparently winging away from the helicopter prior to or during a landing of the vehicle on its final flight last month.

    This additional data will undoubtedly help the engineers and scientists who flew the helicopter to piece together its final moments—and quite possibly make the design of future flying vehicles on Mars and other worlds more robust.

    An image of Ingenuity captured by Perseverance’s SuperCam RMI instrument.

    A broken blade in an ancient channel on Mars.

    • IMO have already said, a few days ago, that they think it will be half hour warning as a maximum and it could possibly start with no warning at all. By saying no warning I assume this could mean the area is so fractured that there may be smaller quakes not necesarily recognisable as the start of an eruption. I would think it would depend on which area of the rift started to erupt or even if it started in a nearby but differnt area.

      • The IMO yesterday put out a review yesterday.

        Volcano-tectonic activity on the Reykjanes Peninsula since 2019: Overview and associated hazards.

        I found some of the points made very interesting.

      • Note that an eruption with very short or essentially no warning is only believed to be possible at the center of the dyke, near the December and February eruptions. Any eruption further north or south along the dyke is expected to have a preceding quake swarm lasting anything between half an hour to several hours, depending on the distance away from the center.

    • The last eruption was 30 minutes, but the tendency is toward decreasing warning time. The next can happen after 20 minutes …. and once they may happen without warning like Stromboli’s eruptions.

    • The study IMO published recently, says:
      “The peak flow rate in the Grindavík dike is comparable to inferred average eruption rate in the first 12 days of the massive 1783 to 1784 Laki eruption when 14.7 km3 erupted in total, during a nine-month period (44). Given sufficient supply, once most deviatoric stress is released along a laterally propagating dike, upward flow can result in an eruption with very high discharge rates. However, sustaining high driving pressure over a long duration of time (weeks or more), as occurred at Laki, requires either a much larger volume of magma in the feeding source than at Grindavík, slowing down the pressure drop as magma flows away from it, or caldera collapse, when sometimes large volumes of magma can be extracted into a laterally propagating dike at low pressure drop rates”

      They say that the peak magma flow rate of Grindavik is on Laki level. Higher than Holohraun and Krafla.
      Holohraun’s peak magma flow rate: ~240 m3/s
      Krafla’s peak magma flow rate: 2000 to 3000 m3/s

  10. Fascinating article, Albert. Thank you!

    “For the role of Joker, I would like to know your pick for a volcano that looks to be unassuming and harmless and that you believe to have the potential to generate a large eruption in the near future.”

    OK, I propose Aso-san, NDVP #4, in Kyushu, Japan, land of calamities.
    https://www.volcanocafe.org/a-wedge-of-worry-aso-caldera-ndvp-4/. Just re-reading that essay makes my point. Still active, Aso has long history of VEI-7 eruptions, the largest ~90k yrs ago. The average interval between these monster eruptions is much less than 90k.

    Japanese people, who must live somewhere, are thickly settled in and near Aso caldera, and to the west & northwest. Clearly they consider Aso-san harmless in near term. It would be a cruel Joker if/when Aso reawakens with great violence.

    • The major eruptions of Aso have volumes in DRE of 32 km3 fot Aso 1, 32 km3 for Aso 2, 96 km3 for Aso 3, and somewhere between 500 and 900 km3 for Aso 4… So the last eruption was a VEI 8 (and actually a lot bigger than Yellowstone 640 ka) and about 5x the volume of the other 3 combined. Its also not resurgent and an open vent right now too.

      Aira is a bit more worrying, not for risk of a caldera collapse but because the caldera is inflating while Sakurajima is still erupting often. Its not likely to be globally important but Sakurajima could do a VEI 4-5 in the next 20 years.

      Really, considering how many volcanoes exist in Japan it is not really all that active. Japan is one of the longer continuous subduction arcs yet only in Kyushu at Sakurajima and Aso are there continuous eruptions, all the rest of Japans active volcanoes are on oceanic islands not the mainland. Compare to Kamchatka or Indonesia where there are multiple continuously active volcanoes in the same area.

    • It’s funny to think that Japan has the most active volcanoes and none of them has produced a VEI 6.
      The concept was my idea and me and Albert wrote the article

      • I did not write it but only put it on the system. This is Tallis’ concept and writing. I had forgotten to set the ‘author’ and it seems this can’t be changed after publication. Tallis’ name now added at the bottom of the post as it should have been from the start

      • Tallis:
        I like your thinking. What about the Kuriles? Any possibility of a VEI 6 or 7 ???

        • Kuriles is a pretty understudied and under-monitored region, I haven’t done a lot of research on the region so I don’t if any of the volcanoes are under some type of unrest other than Ebeko. But I’d say that Mendeleev would be one to watch along with Lvinaya past.

    • Aso-san is at least monitored and known to be capable of very large eruptions. That seems like an ace.

      To me a joker would be a volcano that nobody thinks is a volcano, that then erupts at VEI6 or more, like Pinotubo did, or Hunga Tonga which nobody was paying much attention to.

    • IMHO, anyone who thinks Aso “looks to be unassuming and harmless” hasn’t really looked at all! It’s frickin monstrous!

      • It is noteworthy that the Japanese use the -san honorific on its name, but they don’t do that for most of their volcanos. The same honorific is used on people’s names.

        Mike-san is a more polite and deferent way of saying Mike.

        Might as well discuss linguistics in non-Germanic languages too.

      • Its the idea it is about to do another VEI 7 because it has been longer since the last caldera eruption than the intervals before that, when its last caldera eruption was also way bigger than the other 3 by an order of magnitude. It is indeed a monster volcano probably one of the largest continental volcanoes on the planet, but it is presently a gentle giant.

  11. In my opinion the Royal Flush should consist of following types of eruptions:

    King: Plinian Caldera eruption, at least VEI6
    Queen: Extraordinary large effusive eruption (f.e. Laki-size)
    Jack: a high quality (for human eye), beautiful aesthetical VEI3 mixed explosive-effusive eruption

    • And where they might happen
      VEI6: Chile?
      Large effusive: Ethiopia?
      Beauty: Chile?

      • A Plinian Caldera eruption can happen in Chile, but I’m also thinking about Indonesia. There are many volcanoes with unkown risks. Tambora and Krakatau/Krakatoa were there. Iwo Jima (Japan) is another candidate. Also Alaska is a good place for explosive Caldera eruptions like Novarupta.

        As I’ve noticed with the example of Hallmundarhraun, Iceland can do large effusive eruptions on unexpected places, and RVZ’s Fires are good times for unpredicted effusive eruptions elsewhere outside EVZ.

        Beauty: Etna’s upper scale eruptions are good, also its neighbour Vulcano (usually explosive, but below plinian and sometimes with lava). The Azores are another possible site for aesthetical eruptions. Tourist info about the recent eruption: https://www.visitportugal.com/en/node/156060
        Phreatomagmatic eruptions can be beautiful the way that they both do “lightful” lava phenomena like fountains and flows and the awe of black, big tephra plumes.
        Also intermediatary magma can do coloful eruptions like this. Hekla is a good example for this. Hekla is to weak (until now) for a caldera eruption and for a upper scale effusive eruption. But it does aesthetical mixed eruptions.

  12. Reykjanes right now: It’s all so quiet. (Get the Björk reference?) This is foreshadowing.

      • Or what appear to be more rapid inflation at the Blue Lagoon.

    • While many quakes on Reykjanes peninsula are likely linked to Svartsengi’s activity, there is an ongoing independent earthquake activity between Bláfjöll and Hengill. This can possibly be related to something of Brennisteinsfjöll’s system. Bláfjöll is part of Brennisteinsfjöll as Svartsengi is part of Reykjanes.

  13. One thought I have always had on trying to take educated guesses at what the “next big one” (VEI-6+) would be is that when looking at inflation rates to estimate what volcanoes may be primed and ready to go, we are only accounting for what has occurred in very recent geological history.

    The problem with this, is that a volcano can have a very large magma chamber, and also on the verge of criticality for a very long time without seeing any noteworthy changes for decades.

    Take for example, Chiles Cerro Negro – we know it has been inflating very fast with the recent activity. But if the starting point was basically a dead and fully crystallized magma chamber, you would probably assume that while the activity is significant as well as noisy, it may take a much much longer time before you would see anything akin to a major VEI-6+ sized eruption being possible.

    On the other hand, a volcano such as Antisana (just using this as an example) may have seen a major bout of inflation for over 100 years even more significant than our current fast inflators during the 1800’s. If this inflation ended without eruption, but left the magma chamber in a state that is just below being critical, it wouldn’t be unreasonable to think that it would only need a small fresh injection of magma to tip into a large eruption.

    Given, not saying that fast inflation rates or highly intense activity is not a good warning sign, but it’s far from a prerequisite to get a large eruption in my opinion.

    • We’ve only been monitoring volcanoes for 100 yrs max which is at most 1% of the average lifetime of a youthful volcano.
      I think Chiles-Cerro Negro had significant bouts of unrest over the past centuries as it is implausible for such an unimpressive intrusion to bring this volcano so close to erupting, I must say I was caught off guard when Dr.Mothes said they didn’t know why quakes were taking place at Chalpatan and Potrerillos. I find that so hard to believe. This has been going on for 6-8 years, and there is still no viable hypothesis or model? As I said in the article their current explanation for the past swarm doesn’t align with data. The IGEPN didn’t even cover the most intense portion of the swarm in December, they ignored it! They’re not publishing reports, data, and now they’re saying they can’t even pinpoint how much magma is going into the system or why earthquakes are happening where they are! What am I supposed to think?

      • I think the thought we should be concerned about is for every CCN or Tatun volcanologists discover, how many more are flying under the radar?

        How many are dismissed as extinct or deemed low priority due to lack if funding without taking a detailed in-depth look first?

        • It is impossible to ascertain the number of volcanoes like Tatun but if I were to guess, I’d suppose that 1 or 2 similar volcanoes in the biggest active areas. (Japan, Indonesia, Kamtchaka, etc.)

    • A disadvantage of the slow, longterm evolving big volcanoes is, that their point of eruption often happens suddenly. Chaiten 2008 was an example with Rhyolite (but VEI4).

      How long did they know that Pinatubo was going to erupt with VEI6 1991? Did it show significant inflation before 1991? Pinatubo was the last non-phreatomagmatic VEI6 with evolved viscous magma.

      The last VEI5 was Cordón Caulle 2011-2012. Together with Chaiten 2008 this was a productive period of Andes’ volcanoes with continental ash plumes.

  14. Popocatepetl doing some ash explosions right now:

    • Ash is reportedly falling in some towns of the Mexico City metropolitan area

        • Unusual in that they have been going for many hours continuously. There was a bigger episode in 2023, though. It seems related to large amounts of sulphur dioxide (and maybe other gasses) that increased in output yesterday:


          • The fact that there was an earlier uptick in 2023 makes me even more interested. This volcano has got my attention!

          • Nice map!

            Popo hasn’t stopped erupting all day. It looks like Mordor.

          • Yes, it doesn’t take a break. It’s like what happened in May 2023 when the volcano erupted ash for days almost continuously. However, in 2023 there was incandescence most of the time and lava bombs that would follow ballistic trajectories inside the crater, sometimes even sustained fountains that landed material on the closest part of the flank. This time there was no visible incandescence at night.

    • I’ll see your Popocatepetl and raise you by Eyjafjallajökull.

    • Yes. Right now it is doing a little bit more than that. Half the sky is black.

      I have been watching this webcam too, for the last couple of days.

      • Big ol’ Popo would make a good candidate for Joker. The intensity of the current eruption isn’t special but it’s persistence is making me interested. Hopefully things stay stable

        • The persistence is what I’ve been watching too.
          It’s not just putting up a plume here or there. It’s been nearly continuously erupting for nearly 24 hours and it is worse today than yesterday.

          Also the ash is very black.

      • Mexico’s National Center for Disaster Prevention said it recorded 77 discharges from the volcano and issued a level two volcanic threat level, which requires taking preventative measures and staying a distance away.

  15. Lots of recharge earthquakes under Kilaueas caldera, and still SWRZ quakes all the way down the connector even if not that many of them

    Pele might be about to finish what she started the other week

  16. Some tiny quakes starting up just a kilometer south of Hagafell.

      • 13 quakes all in a tight area S and SSW of Hagafel and all vetween 3:41 and 3:45 this morning. That is most definitely an area to keep an eye on now in my view. Extremely close to an eruption now wherever it comes up. If I had been awake then I would have thought that was the start.

        • The quakes are till pretty deep. 4 or 5 kms down. Is that the bottom of the dike?

        • It’s hard to predict which way the next lava flows will take. There are both slopes towards the south (Grindavik) and west (Blue Lagoon). But it’s more likely that lava runs south. Can lava reach the ocean this time?

        • I’ve had a look at various maps and figures. It is slightly to the west of the January fissures. However, there is a separate fault mapped directly underneath and that fault runs all the way through Grindavik to the harbour.

  17. I see activity north west of Hengill now. Way close to Reykjavik. My interpretation is that these small quake sequences, that are spread all over Reykjanes, are just tectonic stress release from magma influx that may not be super close by? Also, it’s so much easier to resolve these “micro” sequences when the area is mostly seismologically silent.

    Again, it’s oh so quiet…

    • Unsure about Hengill as it acts like a central volcano also. These could be failed intrusions as we saw in Thorbjorn in 2020.

    • Probably faults accommodating the uplift further west. However, there’s a lot of magma under the Peninsula so they could form intrusions later.

    • I’d suppose that the quakes are rather related to Brennisteinsfjöll than Hengill. Brennisteinsfjöll erupted during the Middle Age Fires late 10th century. It’s likely that sooner or later it’s going to follow Fagradalsfjall and Svartsengi, but uncertain whether it happens during our lifetimes …

      Apart from RVZ’s systems it’s possible that other volcanoes on WVZ or Snæfellsnes Volcanic Zone join activity. We should be prepared to get some unusual activity on Iceland that we didn’t had since 1300-1400.

      • Well that area SSW of Eiturhóll is certainly very active today, in fact it is the main centre of activity in Reykjanes area currently. I am sure all of Reykjavik are very pleased that the quakes are all still relatively deep. I am thinking the next place they will be thinking of building berms will be in areas surrounding Reykjavik. Especially in view of the amount of new housing they are planning on building in the outskirts, most of which are on old lava flows.

        • I remember that one of the articles on VC (long before I applied) some months before Fagradalsfjall talks about the possible future of Reykjanes Fires and that the historical Fires of Middle Ages started at Brennisteinsfjöll and later the eruptions wandered along the peninsula towards the west end of RVZ.

          The Middle Age Fires had two parts: The first in the early 10th century with Afstapahraun (Krysuvik). It was followed by small eruptions of Brennisteinsfjöll during the 10th century (950 a VEI2 according to GVP). After this first part was a break over 150 years until the second part began with Krysuvik Fires 1151-88.

          • There are a few things different about this cycle than what happened last time though. This one of course started much further west along Reykjanes than the 10th century cycle, whether or not there is a precedent is not important now it has happened already. It is possible that maybe Svartsengi/Reykjanes/Eldey does do this style of very intense short eruptions with high frequency, while Krysuvik does much fewer and larger fissure eruptions and Brennisteinsfjoll just stays open and makes shields and lava geysers. But we dont really know yet.

            The other thing that is probably much more significant is that the magma composition of both the Fagradalsfjall and Svartsengi lava erupted now is nearly identical (Svartsengi is evolved a bit sitting in the sill) and is noticeably different from the Middle Ages stuff or the lava before that too. The SiO2 and MgO is about the same but there is higher TiO2 and K2O which would indicate the source region is deeper and the very high temperatures of the lava (well over 1200 C) that is probably the hottest historical lava in Iceland would tend to support this. If the magma is different enough that this difference has actually been noted even by the experts in the field then that alone might be enough not to expect a repeated scenario. The volcanoes will probably keep their respective styles but I dont see any large time gaps happening this time. At this rate we are at two fissure swarms in 3 years and with all of the other ones having been called ‘waking up’ publically in that time too. Along with Snaefellsness and Skjaldbreidur too. Seems that whole side of Iceland might wake up.

            The other thing with that, Snaefellsjokull… Most of the volcanoes in that side of Iceland are pretty harmless (well, not explosive, still destructive) but Snaefellsjokull is an actual stratovolcano, and has done a few VEI 4-5s. Its not as big as Oraefajokull or Hekla but is a lot more likely to put Reykjavik under the ash cloud. The eruption style and magma viscosity seems to be very similar to Hekla with high intensity explosive stage followed by very high effusion rate of evolved magma, though there are also basaltic vents too.

            Snaefellsjokull also looks like a potential candidate for a sector collapse too and the last eruption might have had one or even a lateral blast…

          • During 10th century Brennisteinsfjöll did some tephra eruptions (VEI2), so likely some phreato-strombolian behaviour. There the RVZ meets SISZ transfer fault zone. This makes Brennisteinsfjöll a “border volcano” of RVZ.

            Mount Snaefellsjokull looks like something between Mauna Kea and Mount Rainier, a potentially dangerous strato-volcano with characteristics of a post-shield stage volcano with low frequency of eruptions. Last RVZ’s Fires were accompanied by a small basaltic eruption of Ljosfjöll (Light Mountain), maybe this system is more often active than Snaefellsjökull.

          • VEI 2 can just be from tall fountains. Its a bit of a false assumption that strombolian eruptions make more tephra than hawaiian eruptions, tall hawaiian type fountains are what continuous strombolian activity basically is and will make voluminous lava but still a lot of tephra. The Brennisteinsfjoll eruptions were like what happened in 2021 but a lot bigger, so would have variable scale of fountaining with some of it probably quite tall based on the size of a few of the craters, probably similar to those 400 meter geysers in May if 2021.

            Im not sure the age of all of the lava on the Snaefellsness is well established. But it is quite active, nearly all if Snaefellsjokull is Holocene surface and there are at least as maby vents again at Ljosfjoll though spread over a large area. Ljosfjoll probably erupts the same way as Fagradalsfjall with slow long eruptions and intrusions, though it did have a central volcano even with rhyolite back in the Pleistocene so maybe there are surprises. The last eruption has a tall cone and tephra field alongside a lava shield with lots of long channels, so was probably a lava geyser like in 2021.
            Snaefellsjokull probably behaves very different though, given it is a stratovolcano and not mafic.

  18. I have many candidates for the role of Joker. Some time ago I made my own list of the most dangerous volcanoes, so I’ll just post it here. I included volcanoes which have a chance of producing truly devastating eruptions even if the probability of their occurrence in the near future is very low.

    1. Kikai (Under the article about 2023 Turkey-Syria earthquake Hector noticed that “Of the volcanoes in Kyushu, Kikai seems to be the only one in a caldera-making mood”. Kikai is the only volcano in Kyushu to have such an enormous resurgent dome and is the only one that still does rhyolitic eruptions. Of course Kikai will most likely sleep for the next several thousand years. However this does not change the fact that this is one of the worst places for VEI7 to occur.)
    2. Ioto (NDVP #1, the King.)
    3. Campi Flegrei (NDVP #3)
    4. Taal (NDVP #8)
    5. Chiles-Cerro Negro
    6. Ischia (Enormous resurgent dome, second worst place for VEI7 eruption, although also extremely low probability of such an eruption in the near future.)
    7. Cotopaxi (According to GVP, it produced 21 VEI4+ eruptions in the Holocene, of which 12 in the Common Era, the last one in 1877. During a strong eruption, lahars can hit densely populated areas.)
    8. Vesuvius
    9. Apoyeque (NDVP #2)
    10. Nejapa-Miraflores (NDVP #2)
    11. Corbetti Caldera (Low probability of a VEI6+ eruption in a very poor region.)
    12. Masaya (Low probability of Big Basalt Blast occurence 20 km from Managua.)
    13. Coatepeque Caldera (Just another caldera with VEI6+ potential in a dense populated area.)
    14. Machin (This volcano worries me because it has recently experienced some seismic and hydrothermal unrest and may deliver Pinatubo-like eruption. For me it fits the Joker perfectly.)
    15. Agung (It has a history of major eruptions, and the most recent eruption plugged the crater with a lava dome. NDVP #6)
    16. Rabaul (Hyperactive caldera with a city in it.)
    17. Aira (Actively deforming caldera with unefficient open vent and a big city next to it.)
    18. Rainier (Danger of lahars destroying Tacoma.)
    19. Kelud (NDVP #10, VEI4 every few decades.)
    20. Nevado de Toluca (Very low probability of burying Toluca under one meter of ash.)
    21. Mayon (NDVP #9)
    22. Popocatepetl (Volcano with enormous edifice and 5 VEI 4+ eruptions in the Holocene, near Mexico City.)
    23. Nevado del Ruiz (Risk of long reaching lahars.)
    24. Fujisan (Risk of Plinian eruption near world’s biggest city, with direct threat to some smaller cities.)
    25. Tatun Volcanic Group (Mystery volcano near Taipei. Fortunately it seems to be a gentle giant.)

      • And another reason for Nyiragongo (besides its devastating lava flows), is also Lake Kivu, a ticking time bomb (more like a landmine), of which Nyiragongo could disturb it in a way great enough to set off a explosion of methane and carbon dioxide (along with tsunamis) and kill anyone on its shores. Luckily, Nyiragongo’s eruptions have not disturbed the lake great enough to even set it off.

        • There are also other volcanoes in Italy, for example Colli Albani on the outskirts of Rome.

          • Pretty much any volcano is a Joker. For all I know, Kilimanjaro could erupt out a VEI 7 eruption, or Kīlauea produces its own Laki on Hawaii, heck maybe the Three Sisters could end up caldera. Of course, that is all fictitious, but before Hunga Tonga blew up but still erupted, I thought it was going through another phase of island growth, until it blew up. That just proves any volcano can be the Joker, with instruments or not.

          • Pantelleria has a fully-grown resurgent dome. People might not be able to flee the island in time, and one of its caldera collapses takes the whole thing out. Not to mention pyroclastic flows moving over the Mediterranean would probably send a tsunami towards the nearest coasts of Tunisia. I’m not sure how it would happen, what precursor there would be, how does a volcano that doesn’t explode even collapse? As far as I know Pantelleria’s only explosions are the caldera collapses, its gas poor peralkaline rhyolite is basically effusive, the level explosivity when it erupts barely extends beyond the realm of strombolian eruptions. However when the caldera collapses the whole island gets rengulfed by dense, scorching pyroclastic flows. It’s unlikely to even erupt at all in our lifetimes, but there’s always an small chance…

          • That’s a pretty good list, you should write an article. I’d put Tatun quite a bit higher though. All of these volcanoes have the capability of producing a volcanic catastrophe but most of these volcanoes’ current activity doesn’t point to anything implicitly scary. There are specific reasons why Iwo-jima, Cerro Negro, and Grimsvotn are so noteworthy. King is the fastest-inflating volcano in the world, Queen is probably the most seismically active volcano on the planet over the past 10 years, and Jack has been receiving 0.1 km3/year for 20 years.

            The chances of a large eruption at King increases as long as the volcano is under intrusion and while it may pause, it probably won’t end anytime soon. I honestly wouldn’t be surprised if it were to erupt big this year! There has been an eruption every year starting in 2020 and lasting into 2023 with each eruption has gradually increasing in size. Not a good sign

            Queen is just 1 or 2 major swarms from an eruption, magma has left the chamber and slowly crawled up with every swarm since 2022. Queen has an evolved gas-rich magma chamber and has been plugged for tens of thousands of years. Not a good sign.

            Jack has a large influx into a large chamber with a guaranteed eruption sometime in the near future. Not a good sign

            What separates these volcanoes and other volcanoes like Coatepeque or Masaya is that these volcanoes are not only going through some of the most noteworthy unrest of the century but they’ve been building magma and pressure for decades to centuries and they’re just about ready to erupt.

          • I was thinking about writing an article, but there are two problems. Firstly I don’t have enough time to do proper research on every volcano. Secondly I don’t think I can write in English well enough. Maybe in a few years I’ll do this. I’m sure there will be many changes to my list by then.

    • Nice list. I was thinking of Apoyeque-Nejapa earlier today and how dangerous it is. This system has a recurrence of maybe 1000 years, of silicic or mafic plinian eruptions that come out of a fissure system that runs through the metropolitan area of Managua. We’ve seen how quickly a dike intrusion can unzip with the Iceland eruptions. If Nejapa unzips with a major intrusion, it could be merely some hours of warning before a plinian eruption blasts out from the city. I’m not sure if the central crater of Apoyeque works this way, maybe it’s more of a central magma chamber and conduit that collapses in a manner similar to Pinatubo. But Nejapa is a clear dike-driven fissure swarm, and has maar craters as big as 3 kilometers wide, excavated by monster explosions, and has plinian eruptions both mafic and silicic in composition. It could be like Tarawera, but with the Rotomahana blast coming out of Lake Managua.

      There is one hazard that volcanoes that is often underestimated and that is a debris avalanche. Imagine Piton de la Fournaise collapsing into the sea and devastating the coast of Reunion and Mauritius with a megatsunami. Or Popo collapsing southward and taking out a bunch of small cities. Worst is how difficult it is to predict where and when they will happen. They are more common than VEI 6+ caldera collapses but more difficult to foresee too.

      • I knew about Lazufre but only from wikipedia. This volcano can do VEI 8 in the future but I didn’ know many details… until now. Thanks for articles.

        • Glad to get more info. I think it’s a special volcano. It’s a large dome on the crust with a proto-ring fault and it’s in a neighborhood of calderas. I think Hector also may be interested in it based on his Southern Andes articles.

          • I remember looking into it in the past. It’s an interesting volcano. Structurally, it’s a major complex of andesitic-dacitic lava domes and coulees, which are common in the Central Andes, elsewhere being very rare and generally smaller. Not sure if it’s still inflating, now there are other very large complexes of andesitic-dacitic effusives in the Andes that are also inflating, namely Nevado de Santa Isabel-Nevado del Ruiz and Hualca Hualca-Sabancaya-Ampato. Possibly Potrerillos can be included here too since Chiles and Cerro Negro are large andesite-dacite domes, although it has a reduced eruption history compared to the others.

          • (This is replying to hector) According to one of those recent studies it still is inflating. Its been inflating for thousands of years and its more impresssive than Uturuncu, which happens to be a newer feature. There is a large magma body under the dome, of around ~3000km^3. The most recent activity has been a ring of lava domes around the dome and somefualting has been recently noticed around the dome. Andes volcanism is my favorite. I personally think this is the best bet of the region for something big. Not in the imediate future. But its worth watching.

          • I guess the thing to ask the question about is how do you get these huge magma chambers to collapse. The obvious answer is a plinian eruption but the fact these systems form huge effusive structures very easily and volumetrically significant tephras are rare makes it sound like these Andean supervolcanoes are really very hard to set off.

            It might also mean when it does fail the eruption is less explosive than imagined too. Ignimbrite is in some ways more like lava than tephra, I used to think of it as like a fluidized powder but actually it is probably closer to a lava flow that is erupted too fast to degas in the vent so degasses so fast it can slide with nearly no friction. Its not a lava flow exactly but neither is it the sort of glowing avalanche pyroclastic flows that domes or lava flows collapsing on the sides of steep volcanoes make.

            The closest thing in terms of a visual is the Leidenfrost effect of water on a hot surface, only in the ignimbrite it is degassing rather than anything evaporating.

          • Yeah, I don’t know what makes them erupt or go caldera. Another study I found showed that Cerro Galan is alive and has a total chamber size of 22,000 km^3 with 4800 km^3 of melt. These central Andes giants are so interesting to me. They can collect massive amounts of magma. Based on other studies I’ve read, these volcanos just grow huge and eventually, there’s enough buoyant magma creating a dome the chamber roof just fails. When they get to that point is anyone’s guess.
            Studies on Cerro Galan:

          • I’m personally a bit skeptical with these huge volumes that they come up with from red blurs in tomography images that you don’t even know if the image is exaggerating their size or if they might actually be just hydrothermal fluids or fractured or hot rock. Any intrusion of felsic magma will have to displace the ground upwards to make space, which is in fact observed in old fossil intrusions and seems to be the way they grow. Lazufre is a topographic dome but the pile of lava flows that it has could very well account for it. Some uplift from intrusions must be contributing to the mountain but as far as I can tell it’s impossible for there to be tens of thousands of cubic kilometres of intruded material that most articles say hide under Lazufre or Cerro Galan. Only the few largest Hawaiian edifices can get to such size, the largest subduction zone edifices may have a topographic volume of 1000 km3, or 5000 km3 from something like the Klyuchevskaya Group, but more than that seems exaggerated.

  19. As for jokers, my bet is on some crazy, largely unmapped sea mount doing something stupid. Something like Hunga Tonga-Hunga Ha’apai on an even larger scale. The area ratios of oceanic crust to continental crust is something like more than 3:1, no? And oceanic crust is way thinner to begin with.

    • My vote is with you. Lots of submarine volcanoes primed to go, in the Kermadec – Tonga arc area, also the Kuriles need more careful examination.

      • Tofua. PBS Nova put out a really good documentary about Hunga Tonga Ha’apai which included an expedition to Tofua. Tofua is active.

        • Video noworky.

          Meanwhile, (one of) the mbl cam(s) at Svartsengi is showing a beacon of some sort flashing near the left edge of the frame. The beacon has sped up over the past several hours from a bit under one flash per second to nearly three per second. Does anyone know what this might be?

          • PBS is USA public broadcasting. May be a firewall issue?
            It is on YouTube, but many BBC videos are not available in the US.

          • I saw traffic moving near that beacon. Some turned there (toward the power plant) and some kept going straight (toward Grindavik), so it seems to be at a T-junction and is probably just an ordinary traffic signal, likely a yellow blinker facing down the foot of the T and meaning “yield”. Not sure why the period would have been varying yesterday though, but it seems to have been steady all last night.

    • To be fair a seamount also needs to be shallow enough to actually reach the surface, so probably no more than 1 km deep if you want to see atmospheric effects. Harvre seamount had what would have been a VEI 5 if it was subaerial, in 2011, apparently it was intense enough that it actually did erupt into the atmosphere even from nearly 1 km down, but still most of it was effusive.

      So while most of the available crust is oceanic, not all that much is shallow enough to have concerning volcanoes. Even a VEI 8 down on the abyssal plain would probably be unnoticed, like the Gakkel caldera which is as big as Toba but has no subaerial deposit at all so likely stayed in the depths.

  20. Auckland Volcanic field, underneath the city of Auckland, might deserve a mention.
    If two million or so people are living on top of a volcanic field, the hazard is not zero.

    One thing I’ve noticed is repeated small-to mid-sized earthquakes in the Bitterroot mountains in Idaho just north of the Snake river basin. This has been happening for years. There was a 4.9 earlier this week.


    Maybe this activity is strictly tectonic but that entire area has a history of rather severe volcanic activity.

    Also Krakatau seems eminently capable of producing another tsunami as it did in 2018.

    • NASA flew several flights over the Sawtooth Mountains and Snake River basin examining things in fine detail, this was a couple of years ago, so obviously they are concerned.

    • Snake River Plain is one of those areas that no one thinks about but when it does erupt it means business. Craters of the Moon is capable of a Laki sized eruption, there are a’a flows that advanced 30 km over dead flat and unconfined terrain. Laki was longer but most of that was by confining to a valley, beyond the end of the Skafta valley it actually flowed less far than the COFM flows did. The lava is also an unusually fluid intermediate magma, so the flows are probably accompanied by enormous fountains, the size of the cines would suggest even subplinian activity like an Etna fountain but it lasts for days without letting up.

      All of this is done without an elevated central volcano too. It is like Svartsengi crossed with Hekla and 10x bigger. Certainly not some dying remnant

      • How old is the most recent lava flow at Craters of the Moon?

        • Its from 130 BCE, so about 2200 years ago. That eruption was more effusive and made two huge pahoehoe shields (Blue Dragon and Wapi) but the Blue Dragon vents started as a fissure that erupted a voluminous trachyandesite a’a flow that is at least as large as Holuhraun in area covered and likely erupted much faster. Both lava shields are in the range of a few km3, the whole eruptive episode is likely getting to around 8-9 km3 of lava, and probably lasted at least a few years. Wapi and Blue Dragon erupted from opposite ends of a 70 km long rift too, and this was apparently the first time the southern end of the rift has actually erupted so the system is far from dead and if anything getting stronger.

          The huge eruption that made most of the visible a’a is from the Grassy Cone eruption. The volume is probably similar to above but much more of it was in the a’a fissure eruption stage. The official volume of Craters of the Moon is 30 km3 since it begun forming 15,000 years ago and over 1500 km2 of area, which is much larger than Laki or Eldgja, or even Thjosahraun.

          Seriously I dont know why this area has never been discussed on here before, its an absolute monster of a volcano. The average interval between eruptive cycles is around 1500 years according to radiocarbon data, so with 2200 years past the chance it erupts this century is not that low really. If it is anything like at Reykjanes though it probably begins rapidly and erupts within years, no slow buildup. Tbe supply rate to break open 70 km of continental crust and get an intermediate magma so hot as to to flow like hot honey must be immense.

          • 2200 years ago is pretty recent, in geologic time.
            Some volcanoes get overlooked.
            I’m going to read the 2016 article now.

          • I was able to have a better look at the last eruption lavas. The stage one lavas which erupted from a 12 km long fissure system with a primary vent at North Crater where a sustained fountain at least 500 meters high was present. The lavas at the southern fissures are basaltic but the North Crater lavas are a fluid trachyandesite that flowed as far as 14 km from the crater and all combined covered about 70 km2 of land. The North Crater flows are some 15-20 m thick at the edge, while the basalt flows are much thinner at 2-3 m. The total volume of the flow using an average of 15 m is about 1 km3. This should be taken as a lower estimate as the North Crater a’a flow is buried in large sections by later flows, my number uses only a small extra added above exposed segments.

            The Blue Dragon flow covers 310 km2 of land with basalt pahoehoe erupted south of the North Cone area. The thickness is unclear but the flow is significantly inflated and has flow features that only formed at Pu’u O’o where the lava was tens of meters thick even at great distances from the vent. The official volume is 3.4 km3. The output was probably pretty constant but the large number of collapsed lava ponds and spatter cones in the vent area suggests the effusion rate was probably high intermitently and created many rootless shields.

            Wapi lava shield and Kings Bowl crater formed 70 km down a rift from the North Crater and Blue Dragon vents. It is the largest of the lava fields at 6 km3 and 325 km2. It is older than Blue Dragon but apparently younger than the North Crater eruptions, but the radiocarbon dates for all eruptions at Craters of the Moon are centuries in error at times and North Crater is mostly undated. The North Crater eruption likely opened the huge rift, which later erupted at its far end and then again near the origin.

            The total volume, which for the most part is coming from actual USGS figures too, is 10.4 km3. All of the eruptive episodes appear to be of this sort of scale. The official volume of 30 km3 might be rather too low, the real volume might be in excess of 50 km3. Whatever it is though the next eruption is sure to be spectacular if we are lucky enough to see it. Vog in todays world probably wont be as bad as it was to Europe in 1783.

    • Auckland Volcanic field is a typical place for a dangerous VEI3 eruption (f.e. Maar eruption) that wouldn’t be large on global scale, but would have a desastrous effect on a populated city and would at the same time be a significant eruption at a longterm dormant location.

  21. Popocatapetl this mornining is looking apocalyptical.Just a black mass of falling ash.

    • And 4 PM PST 6PM local to the volcano, it is sunny with white fluffy steam, like nothing ever happened. A bit mischievous, Mr. Popo.

  22. I’d differ between VEI6 crater and caldera eruptions. A crater eruption leaves a volcanic mountain behind, while a caldera eruption leaves a depression behind. Pinatubo and Tambora still are mountains. Volcanic craters are usually built by explosions, not by collapse.

    Krakatau, Santorini and Campi Flegrei had typical Caldera eruptions with collapse. I’d assume that the long chains of subduction volcanic islands along the Ring of Fires are a good bet for a caldera eruption. F.e. Marianas, Aleutes, Kuriles, Philippines.

      • Thought that was over to the left. But whatever it is, it’s not new.

    • Today Fagradalsfjall has had some quakes at 6-8 km depth. They are deeper than Grindavik’s earthquakes and indicate the possible common plumbing system of Svartsengi and Fagradalsfjall.

  23. I already know I’ll be writing an update on these volcanoes sometime in the next 9 months. 🙂 I am thinking Ioto is going to erupt this year like it has every year since 2020, Chiles-Cerro Negro has had nonstop new developments since 2018 so it’s likely that another change is on the horizon. Grimsvotn(Maybe Katla and Hekla too) could do a variety of things to get our attention.

    • Next likely volcano (outside Iceland) must be Etna, is suspiscously quiet for months. A rise of new fresh magma can easily do a nice volcano show.

    • Oraefajokull is one volcano I haven’t seen people mention.
      It’s a huge volcano which erupts with great explosivity and will not only cause mayhem on the south coast of iceland with pyroclastic flows & lahars/flash floods – and evacuation is difficult – but it also erupts a high amount of hydrofluoric acid and has the capacity to severely affect much of Western Europe. That is if it did a VEI6 event and blew it’s top, a VEI4 is more likely It is definitely building towards an eruption but it could also be 50-100 years away yet.

  24. I think we should also keep an eye on Grimsvötn.
    Two quakes (2.6 and 2.7), both verified. Depth is quite shallow (1.1 and 0.1 km).

    But no doubt that seismic unrest is increasing, I think that an eruption in spring is likely.

    • I think Carl and Albert both made some predictions a while back and it has since surpassed both. It shows a high level of activity and the occasional jokulhaup but nothing has happened as yet.
      The interesting thing about Grimsvotn is how wide an area it covers, there always seems to be earthquake activity in all 3 of it’s calderas, as well as connecting activity between it and Bardarbunga/ERZ.

      • We’ve been keeping an eye on the activity under the Vatnajökull icecap for a few weeks now. Enough activity to consider getting a new Grimsvotn post written soon to bring things up to date – it just depends on Carl’s availability. I think some of the posts previously written will go first to act as a prologue. Although, it’s not just Grimsvotn that’s getting tickled from below…

    • Think some of the earthquakes are tectonic but would not like to say which.

      • Your comment reminds me of the reputed behavior of the sailors manning the transport ships crossing the North Atlantic in the convoys during World War II. If they were carrying, for example, food, iron ore or coal, they went to sleep fully clothed so that if the ship were torpedoed, they would have a chance to get to safety. If they were transporting high explosives or munitions, they got comfortably undressed to go to sleep. When they woke up, they knew that they had not been torpedoed.

    • There’s been no quakes for 6 hours now. Dead silence.
      Expecting to see a sudden few quakes in quick succession over the same area followed by an eruption within half an hour. In typical contradictory fashion it will probably erupt right at the top of the dyke where nobody can see it, in the middle of the night, during a fog.

      • I can picture it…. Cinema, black & white, 1950s. Dirk Bogart and a team of men, sweating in their trenches, feverish eyes looking out whilst grubby hands clutch pistols.
        “It’s dead quiet out there, sarge!”
        “Don’t let it fool you, private. They’re out there, preparing their assault. Be steady, man!”
        And then the drums start up…

      • Andy, I think we’re still 2-3 days out, maybe more. Average time is 23.5 days, so March 3rd to March 4th is fhe first time period that the eruption might start.

        • Don’t know. The 08.02.2024 eruption occurred at c. 10 million cubic metres of magma under Svartsengi; we must be close to that now.

          Guess it depends on where the next eruption occurs.

    • Not volcano related, but Giggle-translate. The MBL homepage has an article about barbering and beard products with the amazing translated headline of:

      Fragrant human smell in Garðabæn

      Best I’ve seen in quite a while.

    • That’s like my preparations for living in Ocean View Hawai’i: In a cheap house, with a car in the driveway, facing downhill.

      • You should be safe for a while, eruptions that happen that far down the SWRZ to flow into Ocean View are rare, the 3 in 60 years from 1868-1907 seems to have been rather exceptional. A century or a few can easily pass between flows down there. But you might be familar with the Na Pu’u a Pele story pf the last prehistoric eruption to reach Ocean View…

        But at the same time, there is 3 km of hydraulic head between Mokuaweoweo and any vent past the ‘bend’ in the SWRZ where any relevant flows in this direction would originate. So any eruption that far down is going to be both voluminous and extremely intense. Mauna Loas largest eruptions probably put even the largest Icelandic fissure eruptions to shame in terms of intensity, 1950 wasnt even a caldera collapse and peaked in the range of over 10,000 m3/s.

  25. Here is another Popo webcam, from more of a distance. I’m trying to figure out if there is a lava flow or just strong catabatic winds blowing the ash down the mountain.

Comments are closed.