The Katla eruption of 1918

The most famous photo of the 1918 eruption of Katla

October 12, 1918 was just another Saturday. On the fields of France, the Hundred Days Offensive was turning a war which would now soon end, but leave 17 million dead; the devastation would set the scene for an even worse war to come. Far away, Puerto Rico lay in ruins after a magnitude-7 earthquake on the previous day: the damage had been compounded by a 5-meter tall tsunami arriving just minutes after the main shock. In Minnesota on that Saturday, 450 people died in large forest fires which had been set off by sparks from passing trains. And back in Europe, what was called the American flu, also known as Flanders flu (and to be renamed Spanish flu in order not to antagonize the American soldiers), was in its deadly second wave. A children’s rhyme had become popular: I had a little bird\\ its name was Enza \\ I opened the window,\\ and in-flu-enza. In Iceland, everything seemed calm – the flu would not arrive here for another week (on the same day as the independence referendum). The pandemic would soon turn Reykjavik into a ghost town, but that was still weeks away. And October 13 would be a day of darkness in Reyjavik.

Vik is a small, ancient fishing town on the south coast, just west of the ‘land between the mountains’ which we wrote about before. The name means ‘bay’ – because it was the oldest, no further detail was needed, unlike those lesser ones called Grindavik or Reykjavik. Vik has the reputation of being both the warmest and wettest town in Iceland. Its climate is attributed to the influence of the Gulf stream – it is, after all, the southernmost town on the main land. The nearby beach of black sand, Reynisfjara, is famous. You may have seen it in the Rogue One movie. Out at sea, a series of rock stacks show the remnants of an old cliff, now largely removed by the stormy post-ice-age seas. Three of the stacks form the Reynisdrangar, appearing as (and reported to be) three frozen trolls. Invariably, black-sand beaches (and trolls) are a sign of danger. Indeed, 20 kilometer to the north lies Katla: the town was well familiar which its infrequent eruptions (perhaps twice per century) and its somewhat more frequent jokulhlaups, although to some degree protected from both. Katla, of course, is the source of that black, basaltic beach.

Guðrún Larsen (see references) recounts a story of that Saturday, more than a century ago:

Lilja Tómasdóttir (1906–1973), was 12 years old in 1918 and lived with her parents in Vík. On the morning of October 12 she had been washing clothes with her mother (Margrét Eiríksdóttir, 1867–1950) by the small river that runs through the village. At about 11:30 AM she noticed that there were small ripples on the surface of the water in the tub they were using. Her mother then said: “Guð hjálpi okkur, ætli Katla sé að koma?” (God help us, could this be Katla coming?) At 3 PM they had lunch. As the family sits by the table, a man comes and shouts: “Katla er að koma” (Katla is coming). Lilja then ran up the slope above the house and looking east saw the jökulhlaup burst forth carrying large blocks of ice, west of Hjörleifshöfði, 8–10 km away (Larsen’s source was Erlingur Ísleifsson, son of Lilja, 30th of January 2001).

In between, people in Vik had felt a stronger earthquake at 1pm , followed by half an hour of small earthquakes, probably tremor. (Another report from that day gives 1 hour duration for the tremor.) Around this time, people in Mýrdalsandur started hearing the sound of rushing water. And at 3pm, a large cloud quickly rose from the glacier, seen by people in Vik, in Mýrdalur (the ‘boggy valley’ just west of Vik) and at Hjörleifshöfði (the outcrop just north of the label ‘Kötlutangi’ on the map). The cloud was white at first, with the lower part black. One description gives it the shape of an inverted funnel above a large horizontal ring. It was seen as a ‘cloud above the clouds’ from the Vestmannaeyjar islands, 65 km away. From there flashes of light were seen, something we would now identify as volcanic lightning. The photograph of the cloud below is taken from Larsen et al. (2021).

The plume was blown eastwards. By 3:30pm, ash was falling 30 km to the east-southeast of Katla, and by 8pm the ground in this region (Álftaver) was covered in black sand. During this time, as evening fell, the plume became more impressive with a red glow reflected of the lowest cloud. Lightning became incessant, being constant or at most a few seconds apart and lighting up the entire (visible) cloud. The plume reached 15 km height, but the lightning flashed upward to 20-25 km. A drawing of the height measurement done from Reykjavik is shown below, in a figure taken from Larsen et al.

In the evening, the wind became more westerly and the ash was now falling a bit further north, at Skaftártunga. By morning, 1cm of fine black ash covered the ground.

The next two days, the weather was not conducive to eruption watching, at least from a safe distance (which in the case of Katla is far outside its glacier, at least 20 km away). It was cloudy and hazy. The wind was now easterly and a thin layer of ash (less than 0.1mm on average) fell in Reykjavik as the skies there darkened. On Oct 14 there was some ashfall in the north of Iceland, but also in Vik. Ash and tephra was of course only reported from inhabited regions, mainly on the coast and not in the cente of Iceland or near Katla itself! Absence of reports does not mean lack of ash.

On Tuesday (Oct 15) the visibility improved: the cloud was now pulsing, growing higher and lower. The following days the plume was decreasing; it disappeared from view on Friday, Oct 18.

But this was not the end. On Oct 20, two plumes were visible, an eastern one and a weaker western one. It was now dark and clearly an ash cloud, and was lower than before. In the afternoon of Oct 21, the eruption intensified with eruption plumes and lightning similar to Oct 12: there had been another large explosion. Tephra fell again around northeast of Katla, less finely grained than the previous ash. This tephra was damaging: four farms in this region had to be abandoned. On Oct 22, the black ash cloud was higher than it had been before, and seemed to come from a vent further east than previously. This ash plume split into two ash columns on Oct 24, from the eastern and western vents. The cloud was blown towards Vik, which became completely dark: the reports say that windows looked as dark as the walls. Because of the danegrous lightning, the use of electricity in the town was not allowed. The ‘horrible black ash column’ was now stronger from the western vent. The ashfall lasted for 13 hours.

After this, the eruption diminished. The last tephra fell on Nov 1. The black column became ‘black smoke’ on Nov 2 and finally was described as ‘steam’ shortly after. Although some smoke was seen on Nov 10, the eruption was said to be over by Nov 4.

The most famous photos of the Katla eruption were taken towards the end, on Nov 2, when the column was less than 10 km high.These are panel ‘d’ below (Larsen et al. 2021) and the photo below (from Larsen 2010).

When the eruption had ended, the layer of ash was 1 cm thick 20 km from Katla in most directions, a bit more towards the north. Vik had 2 cm. It was thicker on the glacier, mostly 10-50cm. The total volume of tephra was a little over 1 km3.


The flood paths of 12 Oct 1918

All Katla eruptions cause jokulhlaups along the river beds. They melt through large amounts of ice, and this has to go somewhere. Nowadays, the water escapes though a gap in the caldera wall towards the east and comes out along Kötlujökull, the eastern glacier. From there it runs off into several rivers, especially the Múlakvísl and Kúðafljót rivers and their tributaries. In the past, it would also om the other side of the caldera, but this has not happened since the Eldgja eruption in 939.

The flood that escaped the glacier around 3pm came down the Múlakvísl river. It far overwhelmed the capacity of the river bed and spread out across the Mýrdalssandur. The flow rate was a staggering 300 000 m3 /s at peak, with a mixture of meltwater, sediment and ice. (The sandur is in fact the deposits of such jokulhlaups which have deeply buried the soil below.) The flow reached the small hill on the sandur, Hjörleifshöfði, where one person, Kjartan Leifur Markússon, found himself surrounded on all sides. He estimated the speed of the flow as 20 km/hr – impossible to outrun.

Other flows came down river beds to the east. Larsen (2021) provides a description from a 1919 report:

About 15 km east of the edge of Kötlujökull a group of farmers from Álftaver was waiting at a sheep pen on the north bank of the Skálm river for their farm hands that were herding sheep to the pen. Between 1 and 1:30 PM the farmers noticed an unusual humming sound coming from the west. The sound gradually grew louder and around 3 PM the youngsters in the group were sent home for safety’s sake. Shortly afterwards it became clear that a jökulhlaup was approaching along the Skálm river. The remaining farmers hastened across the river as a greyish-black wave of flood water, 2– 3 m high, was closing in “about 10 minutes away” from the ford. Although the herding farm hands made a narrow escape, no human lives were lost and all reached safety.

Afterwards, it was discovered that this flood had overtopped the Kötlujökull and had traveled on the surface of the glacier.

A second flood came around 5pm, perhaps from water traveling below the glacier. This seemed even larger, and carried so much ice that Kjartan Markússon described it as ‘snow-covered hills’. The flood was as much as 8 km wide! At this time, the flood in the Múlakvísl had ended, as it turned out because ice had blocked the stream bed. Off-shore, an icepack formed; on-shore, icebergs as tall as 45 meters (one report says 60 meters) were left behind.

The jokulhlaup continued on and off for weeks, even after the eruption had ended. The last flooding occurred on Nov 26. By that time, parts of the sandur had been raised by 5 meters or more.

(Was the jokulhlaup a lahar? A lahar is a mudflow, where between 20% and 50% of the volume consists of solid material, not water. More than 50% makes it a debris flow. In this case, sediment accounted for some 10% of the volume. So it was not a lahar.)

The jokulhlaup left a large canyon in the glacier, 1.5 km long, 500 meter wide and 100 meter deep. The flow dropped so much sediment that the coast was pushed out by several kilometers. This formed the Kötlutangi (‘Kötlu spit’) which now stretches south from the cliffs of Hjörleifshöfði.

This caused an unexpected consequence of the jokulhlaup. Before the change to the coast line, the southernmost point of the main land was at Dyrhólaey, near Vik. Now the new spit reached further south. And even though this spit has been steadily eroding ever since, it still extends further south than Dyrhólaey. On the most recent sentinel images, I measured it as 500 meters. At the current rate of erosion, that will last another 50 years before the baton is passed back.


Waiting for Katla

Was 3pm on October 12 really the start of the eruption? The eruption had to melt through 400 meters of ice before it could burst into the open. This melt was probably what caused the tremor. The earthquake at 1pm was therefore the likely start of the eruption. Lilja Tómasdóttir’s description of the jokulhlaup shows that this had already broken through the end of the glacier at the time of the eruption cloud. This means there was only 1.5 hours between the first notable sign (ripples in a bath tub) and the major eruption! Even worse, when the cloud appeared, so did the melt water which rushed down the river valley.

So there was very little warning before the eruption, with only the slight trembling 90 minutes before the likely onset of the eruption. Is that common for Katla? Obviously, modern instrumentation might have picked up more indicators. But is the lack of notable earthquakes usual? Both Bardarbunga and Reykjanes gave us plenty of earthquake warning. Hekla did not, at least for recent eruptions.

Katla has erupted typically twice per century. There are usable reports of precursors after the 16th century. In 1625, Þorsteinn Magnússon at Þykkvabæjarklaustur wrote (text from Páll Einarsson 2019)

. . . Anno Christi 1625 on the second day of September early in the morning, around first light, a few earthquakes were felt here in Ver, small and not large. Shortly thereafter thundering noises and din were heard so strong that the Earth moved under our feet. Because the glacier first now (after the earthquake), together with fire and water, moved and exploded. But about the time milking was finished the river nearest to the farm began flooding. . . .

This is very similar to 1918, with moderate earthquakes shortly before the jokulhaup broke from the glacier. In the next eruption, in 1660, again there were similarities. This report is from Jón Salómonsson near Vik.

Anno 1660 on November 3, in the evening towards sunset, fire was seen erupting north of Höfðabrekka near Mýrdalur in Skaftafellssýsla district, with persistent earthquake for about an hour before the fire erupted, though with interruptions. Later that night, at the end of the working day, when people wanted to rest, a glacier outburst arrived at Höfðabrekka with tremendous and heavy water current, following the course of the Kerlingardalsá river east of Fagridalur.

The eruption in 1721 had stronger precursors:

Anno 1721 on May 11, at 11 h AM an earthquake occurred, so strong that people in Mýrdalur were afraid of staying inside their houses. This earthquake was also felt in Síða, in Eyjafjöll and Fljótshlíð. […] The same day at 1 PM, heavy noises with large cracking sound were heard, followed by terrible fire, column of smoke and fumes, that issued from the glacier north of Höfðabrekka, named Kötlugjá, … At 2 PM a flood of slush with a few icebergs flowed rapidly from the glacier … At 3 PM the real jökulhlaup arrived with great haste …

This report also states that the earthquakes continued for a week, with some activity until summer. While the onset was similar, the continuation was quite different.

In 1755 we have a familiar, reliable reporter: Jón Sigurðsson, from Laki fame, who would give the fire sermon in that eruption. At this time he lived in Holt, southwest of Katla.

…The events began on Friday, October 17, shortly before noon, with strong earthquakes, like houses were rocked, that lasted till the end of the day and the following night, so that many did not dare to stay inside their houses because of the movements of the ground and worries that the houses might collapse. In the evening of the same day at sunset frequent lightning was seen, that continued throughout the night together with tremors and movements of the ground. … In the night following October 17 and the day a flood and jökulhlaup originated in the so called Kötlugjá.

The eruption apparently broke out of the icecap on the Friday evening, as evidenced by the lightning. The earthquakes continued for a number of hours before the eruption; the tremor afterwards may have been the meltwater, attempting the break through the glacier at the depth of the little ice age.

In 1823, the earthquakes were weaker:

About 6 pm an earthquake was felt here in Vík (…), a few sharp and short shocks, but not hard enough to rock houses significantly, followed by weaker but persistent movements, later mixed with harder shocks similar to the first one, until 9h PM, then all became quiet for a quarter of an hour. Then an eruption column ascended at high speed … Near midnight … a water flood began, mixed with ice slush and glacier clay, east along the Víkurfjall mountain …

The 1860 eruption had a longer time between the earthquakes and the jokulhlaup:

On Tuesday May 8 at 6 to 7h AM earthquakes occurred large enough to shake houses and make cracking noises. At 5 1/2 h PM a jökulhlaup came down the Múlakvísl river with great speed …

These reports indicate that the sequence of events in 1918 is indeed typical for Katla, with earthquakes in the hours before the eruption, and jokulhlaups following after a few to 12 hours. There are a few hours of warning, which should be used well since when the water come it is too late for running.

Why is there no more warning? Many eruptions are preceded by weeks of earthquakes, but not here. Magma clearly does not have to do much rock breaking in Katla. There are a few options. First, all these were summit eruptions. Katla does do rift eruptions (Eldgja comes to mind) as well but has not done so recently. Unlike the other big beast volcanoes in Iceland, it only has one long rift, stretching for 70 km northeast. There is also a short rift going south, but this has not erupted since the ice age. Summit eruptions do not require long dikes, which removes one reason for long earthquake swarms. (The 1721 eruption may have activated a rift, from the continuation of the earthquakes, but the eruption remained confined to the summit.) Second, all these eruptions are basaltic. Katla has done silicic eruptions as well, with the large Vedde ash eruption as a good example, but even though these account for 5-10% of its eruptions, they have not happened in the last 1500 years. It is not clear, though, why this would be a reason for less earthquake activity. Finally, the magma may already reside at shallow depth, with the upper ground layers above it softened by the water percolating down from the ice cap – after all, this is among the wettest areas in Iceland. Katla is among the largest sources of volcanic CO2, constantly degassing even though it is not erupting: this also suggests that magma resides at relatively shallow levels. The large effusive Eldgja eruption occurred only 20 years after a normal Katla eruption: the deep large magma source which fed Eldja is apparently not affected by or directly involved with the summit eruptions.

The 1918 eruption was therefore in many ways typical. But the long time of quiescence is not. Katla eruptions tend to be spaced 40-60 years apart (apart from the minor phreatic explosions under the ice which happen on occasion), whilst it has now been over a century since the last one. There is no obvious reason for this delay. Global warming has affected Iceland, but it is not clear how that could affect Katla! (In the UK one would blame a lack of funding.) The most similar period was perhaps from 1500 onwards. Around 1500 Katla had a large eruption – it is not documented but there is a significant tephra layer from around this time. After that, there were small eruptions in 1580 and 1612, whilst the next major eruption was in 1625. Thus, the current interregnum could be similar to that period if the weak eruptions this time were too small to break through the ice.

Is Katla overdue? No volcano is overdue – eruptions do not occur on schedule. Neither is there much evidence for build-up of magma, apart from Katla’s tendency to emit quite a lot of CO2. The next eruption will remain unpredictable and will happen when we least expect it. It could still be 50 years away – but one day, someone in Vik will again see a ripple in the bathtub. A few hours later, the plume will rise and the waters will come. One day.

Albert, June 2024


The explosive basaltic Katla eruption in 1918, south Iceland I: Course of events, tephra fall and flood routes: Guðrún Larsen, Maria H. Janebo and Magnús Tumi Gudmundsson.

Jökull, No. 71, p. 1-20, 2021.

Haukur Tómasson: The jökulhlaup from Katla in 1918. Annals of Glaciology, Volume 22, p. 249 – 254, 1996.

Guðrún Larsen: Katla: Tephrochronology and Eruption History. Developments in Quaternary Sciences Vol. 13, 2010, p. 23-49, 2010

Páll Einarsson: Historical accounts of pre-eruption seismicity of Katla, Hekla, Öræfajökull and other volcanoes in Iceland. Jökull, No. 65, p. 35-52, 2019.

333 thoughts on “The Katla eruption of 1918

  1. I find the current dormancy period for Katla to be very fascinating. Could the cause be a weaker supply rate, less numerous intrusions, or a plug? The 1918 eruption was considered small up until fairly recently so I am thinking there is a chance that 1755 eruption was a bit larger than some might expect

    • The 1755 eruption was probably comparable to 1918. The volume is reported as ~1.5km3.

    • It’s interesting to me that Napolitan officials and a large portion of the citizens of Pozzuoli seem to still be under the belief that if they just keep ignoring the problem it will all just go back to normal in due time.

      All whilst Campi Flegrei does its best to remind people it exists. If it was a person I’d imagine it banging pots and pans shouting “I exist! Acknowledge me!”

  2. Looks like part of the active cone is ready to collapse into the center lava pond. See – Sat 9:38:55 pm Iceland time 15-June-2024.

  3. The eruption in October 1918 coincided with the dramatic events during the final month of WWI, when they negotiated about the conditions of truce. Maybe this prohibited the full recognition of the Katla eruption in Europe.

    The tephra eruption reminds to Grimsvötn’s eruptions, but is Katla always bigger than Grimsvötn? Today an epic Jökulhlaup would be a threat for the Ring Road which connects Reykjavik to Vatnajökull and Krafla area both for tourists and scientists.

    Without the ice cover, it would be easier to get a view on Katla’s caldera/crater. There is frequent hydrothermal unrest on Katla, which indicates that heat and hot water must be there always. Magma must be at shallow depths and keep the system open, but (unlike Grimsvötn) without frequent magmatic eruptions. The magma reserovir is able to wait long time, to get the conditions for a major eruption. There was a mystery about why Katla didn’t erupt after Eyjafjallajökull 2010. Maybe Katla will wait until the Reykjanes Fires continue further. During 10th century Katla erupted after the first Reykjanes eruptions (Kryusvik with Afstapahraun) had happened.

    Does the long dormant period mean that the next eruption can become larger then on average? Hekla f.e. did its famous H eruptions after long breaks. H1 (VEI5) 1104 after 250 years.

    • Might be worth considering that Katla today is now over 1000 years past a rifting eruption (eldgja) so despite having made little progress filling up the hole it could be ‘mature’ as in largely recovered from that. Its something I have considered after looking at Kilauea following 2018. A caldera forming eruption through lateral drain will make both a physical collapse but also a lot of elastic strain. The physical collapse will fill by either eruption or resurgence usually it is both in basaltic calderas. But the elastid deformation will take up most of the pressure early on. Even in a hyperactive volcano like Kilauea it was enough to prevent any eruptions for over 2 years, and to date only 0.2 km3 out if an estimated 1 km3 of magma fed to Kilauea has erupted after 2018. Now take that to a more normal strengrh volcano and the timescales are orders of magnitude longer. Katla is no pushover but Eldgja was a gigantic lava flow, the same volume as Hawaii erupts in a century, and Katla has a supply rate of only around 10% of Kilauea, so not surprising Eldgja had a big impact. Maybe finally Eldgja has been recovered, and instead of just erupting quickly the magma chamber is growing again like a fully mature caldera once more. Just a theory though.

      Grimsvotn migbt be an insight to Katla in the middle ages. Grimsvotn is only a couple centuries after a similar huge eruption. Its unclear how much Laki contributed to its modern caldera but I would be surprised if it wasnt important. Before 1783 there werent a lot of eruptions reported but after 1783 there are rather more, including some bigger ones. Grimsvotn is more active and probably has a higher magma supply than Katla but its not that dissimilar. Grimsvotn is probably not a good pick for the source of the next rift in southern Iceland, im going to go against the VolcanoCafe consensus on that one. Bardarbungas southwestern neighbor Hamarinn is my pick followed by Torfajokull and likely combined. But Katla is probably closer than I thought before to an Eldgja 2.0

      I also do wonder really if Eyjafjallajokull and Katla are separate, 2010 started from a fissure between them and apparently intruded into Eyjafjallajokull caldera from the east rather than being a flank vent of it. At least that is how cutouts of the 2010 plumbing look. Maybe 2010 was a ‘failed’ Katla eruption that invaded a neighbor instead of going into the magma chamber. Earlier Eyjafjallajokull eruptions were minor silicic eruptions while 2010 was a basaltic-intermediate eruption and subplinian not unlike a lot of Katla eruptions. Not saying this is true but its intriguing.

      • 1821-23 Eyjafjallajökull and Katla did eruptions close to each other. Some scientists took this as an example how the volcanoes would act 2010 again. But this prediction failed mostly. Katla only did a minor subglacial eruption with a small jökulhlaup.

        During last 8500 years Katla did three fissure eruptions including Eldgá. They were “dominantly effusive, producing lava, although a large explosive component”. On average this would mean a fissure eruption every 3000 years. Volcanoes can do surprises, it doesn’t look likely now.

        A different thing is the risk for silicic eruptions. Katla did them 14 times since 8500 years ago. No silicic eruptions during the recent 1000 years, but this can change, if magma has time to evolve. Hekla showed how volcanoes can change their behaviour over time. Mabe Katla does the opposite way now. The silicic eruptions had the size of 0.02 to >0.27 km3. Would they have a similar development of events as the 1918 eruption?

        • 1823 Eyjafjallajokull eruption was alot smaller than 2010 was more my point, and a different composition. So theres a lot of variables around it if you want to find a correlation of the two erupting. Katla erupts more often too so technically it is more accurate to say some Katla eruptions have Eyjafjallajokull eruptions associated rather than Eyjafjallajokull eruptions causing Katla to erupt.

          I also do wonder how well we know the eruption history of volcanoes in this part of Iceland before the past millennium really. Obviously Katla hasnt had any other eruption close to as big as Eldgja probably not since before the Holocene and possibly ever. But it has had large lava eruptions otherwise and its not unlikely Myrdalsjokull covers some evjdence, as does the outwash plain. The obvious and easily accessible flows erupted around Hekla have enormous margin of error in age, some are literally millennia, and that is at Icelands most famous volcano and maybe the only one of the central volcanoes that is easily accessible. I wouldnt rule out a Holuhraun sized lava flow erupting north of the caldera if this goes on another few decades.

          • Fissure eruptions of the big volcanoes were often big ones: Eldgjá by Katla, Laki by Grimsvötn and Holohraun, Veidivötn and Vatnaöldur by Bardarbunga. 1875 Askja also did a fissure eruption linked to the general large eruption 1875-76.

            Can they also to small or moderate fissure eruptions?

          • I should have written “Fissure swarm eruption”, that’s more correct.

          • Most of the eruptions are smaller… The average size of the Veidivotn eruptions are not that different to Holuhraun, 1477 would be about 2 km3 of magma so maybe only 50% bigger than Holuhraun if it was effusive.

            Thjorsahraun, Laki and Eldgja were really extremely large, about 5-10x bigger than is typical. Holuhraun was 10x smaller than Laki but it is easy to forget Holuhraun was still one of Icelands most voluminous eruptions, number 5 among lava flows I think, and 8 overall in over 1000 years of history. Eruptions over 10 km3 probably have intervals of millennia at individual volcanoes, and maybe even overall, Eldgja and Laki being less than 1000 years apart is probably very close.

            Outside of Reykjanes I think Iceland might have some lava eruptions at Hekla or nearby, and at Askja. Otherwise it is VEI 2-4 tephra eruptions. At least for the next few decades I think anyway. Veidivotn area will probably rift some time in the late 21st century.

          • I guess eruptions between 0.1 and 1 km3 are not uncommon, less than that are most common. But bigger than 1 km3 of magma is rare, maybe a few times a century or less. Can be effusive or explosive. Rift eruptions from the large calderas are usually around 1 km3. Eruptions over 10 km3 are very rare and are even rarer if you dont count shield eruptions, there might only be a few >10 km3 fissure eruptions in the Holocene and 2 were after settlement… 🙂

          • In Iceland, fissure fires top at around 5 km3, with a few much larger but exceptional events. Below 5 km3 you get the full range, with of course smaller ones more common than bigger ones. The current Reykjanes ones are near the bottom of the range.. Those large events seem not just a larger version of the normal fires: there must be something else than magnifies them. Perhaps the large ones are sourced directly from deeper magma?

          • Was the Fimmvörðuháls eruption 2010 an example for minor fissure swarm eruptions that Katla can do as well as Eyjafjallajökull?

            Grimsvötn/Bardarbunga occasionally do (relative) small fissure swarm eruptions like Gjalp 1996 in the Vatnajökull area. Maybe only the bigger fissure swarm eruptions of both volcanoes happen outside of Vatnajökull.

          • Probably yes although 2010 was maybe on the small end. The suspected subglacial eruptions at Katla after 1918 might have been similar size.

            Gjalp was not a small eruption, it was actually Grimsvotns biggest recent eruption, a bit bigger than 2011 though not as fast. 0.4 km3 of hyaloclastite.

          • Gjalp 1996 was big in relation to f.e. Grimsvötn 1983, but small compared to Laki or Holohraun. It always depends on to what we relate it to … 😉

      • The recent recognition of Fagradalsfjall as its own system (at least according to the GVP) has me wondering again about the criteria for parent/child volcano versus independent volcano. I’m still not convinced that Novarupta and Katmai aren’t one single system and not just neighbours.

        • I would not have called Fagradalsfjall as a central volcano. It is one rift among many, and there is no evidence for a lasting conduit with a stable magma chamber. That is not the normal mode for the Reykjanes peninsula. Wait a few decades to see what happens.. but I expect that future eruptions will not be at this same location.

  4. Thank you for the article, Albert. I hope to see a Katla eruption before I depart this plane of existence….but not at the expense of Icelanders’ villages and towns.

  5. Looks like God needs to update the universe’s video drivers. I’m seeing the HUD and sprite layer but no world geometry …

    Also, there was a big cone wall collapse at about 16:40.

    • Why isn’t the image showing up? Goddamn I hate imgur. I’d have used tinypic except I can’t seem to find the upload form there for some reason!

      • What was the link you were trying to insert? If you give it without the ‘https’ bit and anything else that will help wordpress not to recognize it, we can at least see where to point

        • https : // i dot imgur dot com/4HfKpYa.png

          It’s (supposed to be) the direct link to the image. The one you’d put in [img] tags on a forum post, etc.

          (You can’t view the source code for my earlier comment?)

          • The link had been removed entirely from the comment, so there was nothing to view! Even though the link was for the image, imgur redirected it to full site. I am not sure why or how. I have copied the image (at reduced resolution) and linked to the copy in your comment.

            Just putting in the name of the link (without ’embedding’ [img] notation) seems to work:

      • I just open the imgur image in its own tab which loads it directly as the .jpg so you can copy it from the URL.

    • I’m also not happy with Depth of Field effect. It seems to get blurrier the older I get. 🙂

  6. If the Gulf Stream was not going past Iceland and if the Greenland Current woud have total domination over the Iceland region in an imaginary scenario, woud Iceland be even livable?, I remeber reading older weather data from past periods, suggesting during the ”Little ”Ice Age that the Gulf Stream was pushed much further south than it is today, putting Iceland and Norway coast in the freezing polar waters instead, those colder sea surface temperatures is going to depress both winter and summer temperatures alot, I do remeber reading that Reykjavik Bay was icebound in winter in 1600 s, something that does not happen today, even during severe coldspells. Cold Currents stops all tree growth at labrador penninsula down to latitude 54, past preindustrial cold spells expains why forests never came back after the vikings cut them down

    • And I have a friend that lives in Kailua Konas lowest part since 2007 getting 32 c days daily and very high UV index.. he been insanely spolied away by good weather for nearly two decades now, he complains directly even when it goes below 27 c 😛 that I myself finds very hot. He woud find Iceland as cold as an Ice Bath even in summer, even a winter night in Kona is much hotter than a warm summer day in Reykjavik! But for me it will be Iceland later when I have some kind of work skill

      • High UV is worse than near 0 temperatures in my opinion, from someone who lives where there is no ozone layer… 🙂

    • Is the sky color diffirent in the sourthen hemisphere than the northen? I mean less dust from the large northen landmasses, you Australians sourely gets a nice deep deep blue skies as result of molecular reyleigh scattering rather than particle
      mie scattering, in Mediterranean and Arabia its almost always creamy du to dust in the skies

      • The only place in the northern hemisphere I have been is to Hawaii so I dont know, but Tasmania is claimed to have the cleanest air on the planet. I dont know about that, I think Antarctica would easily hold that title, but it isnt exactly habitable either. Tierra del Fuego and Fjordland might be true competitors though.

        I would think Iceland has very clean air outside of vog though. A lot of air pollution in cities is particulates from engines, especially diesel engines which are so common in 2000s-2010s euro cars, and which will go away naturally as EVs become the norm. If you drive an EV in Iceland it is also volcano powered 🙂

      • I talked to a photographer once who could recognize southern hemisphere photos (Australia and South Africa, mainly) from the light. Indeed, less dust at most times. South Africa does get dust form the Namib in northwesterly winds, and Australia too has desert storms and a fair amount of forest and grass fires, but the brightness is notable at other times.

    • I wants to move to Iceland being free resident, but I guess I needs to become somekind of professor to even have a remote chance to get a job, we in nordic countries are the worlds elite, the worlds highest living standards and educational levels, that means that the job market in Scandinavia is mostly for Einsteins, and that does not look good for me with bad iq and distaste for maths. But I do still trusts very strong in voucational education, beacuse that always works everywhere, and is always wanted and I guess its best to do that training in Iceland and not here as it takes way too long here to figure out what I wants to work with

      • Ideal woud be if Hawaii was a scandinavian colony 🙂 but its not

      • You can work in a fish factory or the metal foundary. Although I have done the first one and wouldnt recommend it… Also the fact it is in Grindavik which might be complicated now.

        It might be worth investigating other mental conditions and assessments. Autism I think is a bit of a wastebasket term for anyone who is socially awkward and introverted and they see that it is uncurable and give up…I thought I had it until last year when I got an ADHD diagnosis, which is easily treated.

      • I think voucational education is best to start with, its always wanted but with 100 s 100 s of choices even 1000 s .. it can take a lifetime to sort out what suits me and what not suits me, Im on a pathway similar to you voucational skill and learning some of these are very theoretical while others are not or less so, and yours are both theoretical and partical ( machinist ) I doubt my IQ is good enough but Im sharp minded enough to not concidered to be very stupid and I works well socialy with others.

        Its a shame that Hawaii is not some kind of Nordic colony… so I coud live there ”for free” because it woud be better weather and the most fun volcanoes. But Iceland is pretty impressive too of course! and looks totaly fantasy. Icelands free energy is amazing and they have really warm homes! which I does not

        • I am only a training machinist really because of an employment program forwarding me and I went to the first offer, was never a first choice. I made the mistake of tdying to turn an ingerest into a career path, its probably the worst bit of advice we were gjven back as teenagers, that yku are undesjrable without a degree and trades jobs are low class. Guess which field is saturated and which is extremely in demand…

          I dont know how European education works but getting a trade job is way better practically, there are always things that break and need fixing, parts that need to be made. Especially for an intent to move international. The only ways to get money from nothing are smart investing or being desirably skilled in a market in demand.

          • Correct. Currently in the UK anything manual is well paid because the jobs MUST be done and someone needs to do it. Carers seem to have a low status probably because its almost all immigrant via specific visa. Lowest paid are degree owners for a useless degree at a poor uni. Low priced clerical work at best, thousands of applicants per job. “Inside job with no heavy lifting” they may be.

          • Nothing bad about having a degree..! It is not a certain path to a job, but it gives lots of opportunity to develop yourself. Carers and nursery teachers have extremely low salaries in the UK not because they are immigrant but because they are women. Their salaries are in effect set by the government. When people were willing to put up with the salaries, they were reduced further. It is called exploitation.Now they are so low that caring jobs are done by migrant workers and nurseries are closing for lack of staff.

          • While you are correct in saying employability is easier with a trade, salaries are on average somewhat lower.

        • My own GF is neurodivergent and performs very well socialy with other persons as do I, Autistism spanns an enormous range of personality symptoms and abilities, and its a disgrace that western society sees it as a impaired disease in the brain, when its just a personality variation in the brain, and how the brain is wired compared to ”normal pepole” the brain waves neuron network is is diffrent and what is personality functions divergently, but any disease its certainly not as you say. I preforms well socialy with others yes, but is more and more getting bored with society as everything here is so familiar for me, Iceland is where I wants to be

          • Im not a psychiatrist so dont take this absolutely seriously but if you have a girlfriend your social skills are a lot better than you think and you might be overthinking most of this stuff. 🙂

            Autism also can be a disease if it is severe and presents a handicap to doing basic function. But a person who is in that position and a person who has mild autusm are very different in basically every way which is why I think it is probably a wastebasket term like IBS or ‘heart disease’. Mental health now is like genetics in the 1920s, we know its a thing but not much else

        • voucational degrees are highly sought after and often easier so I think I will start with that

        • Social skills are acceptable but Im not soure how smart I am and Im getting bored soon with nearly absoultely everything, with acess to internet and the insane wonder that is Google Earth and many personal travels to Hawaii, Iceland, Italy and other areas I have a pretty good yet very rough grasp on the planet and how it looks like, and what can be found and seen. I seen it all in a sense, yet I seen very little of the world too. Still Hawaii and Icelands ever changeable volcanic landscapes provides just as much joy to me as it does for you, so there is that stuff too

          But ultimately I wants eruptions on a very collossal massive scale so I can enjoy to see spectacular photographs and study the effects on the atmosphere, maybe African Rift or Iceland coud cook up something gigantic for me, they have capacity for huge eruptions as well do Hawaii even if that one is more well vented than the latter examples

        • I wonder what a tropical Iceland woud be like in these scenarios! its very true for soure that Icelands landscapes are formed by volcanoes, but the real world landscapes in Iceland are equaly formed as much by the cold Ice Age dominated glacial history of Iceland, with volcanoes erupting under glaciers, forming volcanic landforms like table mountains, tuyas, moberg hills, ridges and pyramids that we are so familiar with. Without the Ice Age prescence these landforms woud not exist at all in Iceland. No fjords, no tuyas no souch features

          Perhaps a combination of Samoas rainy eroded landforms for Icelands older parts outside the rifts and the active volcanoes themselves woud be similar to Galapagos and Africas rifts volcanoes. North of Vatnajökull is fairly similar to African Rift thats way north of Kilimanjaro with some volcanoes like Askja having large and broad calderas and being unimpressive topography wise, while Bardarbunga looks like an Galapagos caldera a bit

        • And some of these scenarios makes Australia really unlivable and Chad ends up without a home 😉

          They are quite impossible due to the Moon stabilizing the Earths equator, still Earths tilt vent offset a bit in the cretaceous 12 degrees more than normal but it corrected itself due to the moon ..

          But without the moon and with 4 gas giants.. and solar thug it woud be very bad for our tilt

        • I woud prefer seapole so I can have a winter thats less cloudy and grey and Iceland gets beach weather!

  7. Looks like the lava pool just drained out, away from the Sundhnukar camera. The level went down surprisingly fast, at 12:08 it was still full to the brim, 12:14 it is no longer visible.

    • It has been doing that periodically for at least the last three days. The rim of the pond is getting higher, so it could be that it appears to drain out more even if the lowest level is the same as before (which I don’t know if it actually is since we cannot see it). The big question is if the lava drains back inside the cone, or if it flows out to the lava field in tubes under the crust. Maybe a bit of both is happening.

      • Probably at Brennisteinsfjoll in the last Reykjanes fires, at Husfellsbruni 2. Looks like a kind of overflowing drained pond. There was also a lava lake on Surtsey but I dont know if it was convective.

        • Does the present lava lake indicate that we’ve got to the peak activity of the volcano? It looks very healthy as if it can continue even longer than the March-April activity.

          • I dont think so, it looks very similar to the activity in the last eruption. The eruption in March had to build up the terrain from scratch in a depression, the output if tge vents went into inflating the flow field near the vents more than cone building until the output already declined. Now the eruption ending May started on top of this, it didnt pond at the vents outside of where there were already lava ponds last time, which is the case for the south lake.

            I dont know if we should expect another 2 month eruption, it could happen for sure but its equally likely to stop a lot sooner. The input to the sills seems unchanged, so we can expect another fissure eruption.

            The trend seems to be now that there is significant overinflation before it breaks, with net inflation doesnt seem the system is losing power yet and if anything that trend means the rift is full so more will erupt and faster. Krafla was the same, small eruptions and lots of intrusions with little net inflation. Then large eruptions and little rifting, the caldera inflated a lot in thjs time and eruptions were powerful. So it seems like now Sundhnjukur is in stage 2, rifting might be over and the input of the magma exceeds the amount that is intruded. So we might be half way but the majority of the lava is probably still to come us my guess, unfortunately.

    • I watched the lava pond for several hours spread across 2 or 3 days.. there is cyclic behavior, with large lava bubbles bursting when the pond drains about 3 – 5 meters or maybe more.. then refills back up again. Today however, it appears that part of the pond wall broke, letting lave flow around on the east side, then towards the north. Tonight the Live-in-Iceland cameras are highlighting this new lava flow.

      • Gas pistoning, its a common behavior of lava lakes in Hawaii although I dont know of it being seen in a lava lake not fed by a submerged vent, so perhaps it does have a connection a little deeper. There was that fountain in front of the April cone before it reactivated which might be active still, allowing connection a little deeper than just under the wall. But just a guess.

      • There are two separate flows out from the cone, one to the north and one to the south, so the overflow is not going around on the east side. If you look at the cone from the opposite side (Sandhóll cam), you can see that the cone is steaming from the NE side, just as it does from the SW side. This is a clear sign that lava exits the cone under those steaming parts. A drone flight from yesterday confirms that the flows are indeed separate. The size of the pond is quite impressive when seen from the air.

        The southern flow definitely exits the pond through tubes under the crust. Sometimes in the webcams you can see how a small flow breaks up through the crust to the south below the perched pond. You can see it in the linked drone video around 30 minutes into the video. There’s also some obvious fresh pahoehoe from the breakouts in that area.

  8. I’ve looked for the IMO article on the most recent subglacial eruption of Katla 2011. It happened in July 2011, only two months after Grimsvötn’s last eruption.

    They say that “Some weeks before, microseismicity had been registrered”. 1918 it was impossible to recognize this microseismity anyhow. Today we would have the chance to observe this. 2011 IMO published this Tremor graph in the Icelandic news:

  9. The is the UWE tiltmeter. It seems to be somewhat rapidly inflating. The SDH tiltmeter is at a plateauing standstill, while IKI is slowly inflating. The seismographs seem to be malfunctioning. Is Kīlauea ramping up to something?

      • Ok that is crazy. 9 microrad in 12 hours, or 0.75 million m3 an hour if the correlation is reliable. Thats 200 m3/s supply.

        I am skeptical of this being real, but even if it is 10x too high thats still crazy anyway. And the south caldera is quaking again with some uplift at SDH, I think we are gonna see another run southwest and probably a lot more lava than last time. To be honest, with how fast the 1974 eruption was despite its small volume, an eruption in the same area with the volume of recent Halemaumau eruptions might actually reach the ocean, which is crazy.

        • Looking on the UWE 2 day tiltmeter, it seems to be slowing down… (also live)

          • Its normal to have small variations, they are probably DI events superimposed on the rapid inflation. Its obviously complicated interaction of multiple magma storage zones if you can get rapid uplift at the same time as magma draining. And all of this being within 2 km of the surface or the tilt wont really show it, the rift connectors and major south caldera system are not even factors here. Although, the start of the SWRZ connector seems to at least reach a shallow depth by how much it moves SDH, and erupted unexpectedly not that long back.

            I also think we can rule out a slow passice eruption, that was exactly the scenario on June 3 and it stopped. And the supply refilled in a week… No, this us going to be a fast intrusion and I am doubtful there is much room left in the rift to prevent that intrusion reaching the surface at full power…

            It js of course unpredictable to a specific number. But, the caldera has seen 15 cm of extension beyond the trigger point for the January intrusion, which itself began after 20 cm of extension beyond the trigger for the last summit eruption. The recent intrusion was insignificant to reduce pressure and small in volume yet still erupted anyway or showed how close it was in January if that lava was pushed out. At the current average rate the +20cm point over January will be in about a week to two weeks, around the end of the month.

      • 3-4 days long DI event superimposed on very steep inflation.

      • Look like the SWRZ connector is just starting to activate. Probably the summit chamber had not been refilled until now. Likely, the dike elastic rebound canceled part of the intrusion deflation of Halema’uma’u in UWE, or just shifted the direction of deflation away from the axis plotted.

        • In September 1974 the Halema’uma’u one-day-eruption began, when they expected a SWRZ eruption like 1971. SWRZ active times can lead to short eruptions on Halema’uma’u as well.

    • IKI tiltmeter live. I think something is happening and there are currently 4 earthquakes in the past 2 hours… it might only be one off, but the weirdness is going.

      • Now that the seismographs are back online (with missing data), I could see a strong somewhat harmonic tremor on the HAT seismograph. It may not last long, but I checked other seismographs and either slightly detected or not detected this signal –

        (This is live too, just in case).

    • Its not an intrusion or tremor but there was a 3.1 on the ERZ connector which us the visible quake near where the instrument resumes. PUHI station never had the transmission issues for some reason so you can see what happened there.

      Still you are right about the inflation. Since the last eruption the tilt has gone up by 30 microradians, about 2 a day. UWEV tilt seems to be an approximate correlation of 1 microradian = 1 million m3, so 30 million m3 in 14 days. Or, extrapolated, a supply rate of 0.72 km3/year… obviously its not really always this high, DI events probably cut out nearly 70% of that uplift on average, but not in times of surging supply which seems to be whats happening now. Might well get another intrusion this week if this keeps going.

      It would be nice if HVO released the full uninterupted tilt data from 2018 to present, now we have actually had an eruption outside the caldera. They did that a while back and the uplift was obvious but since September the deformation and dynamics have really stepped up even more. HVO said that to recover the pressure drop of 2018 would mean an eruption outside the caldera maybe not until 2030 at Pu’u O’o supply rates. And that It might be a transition of dominance to Mauna Loa. Well, ML erupted, and went back to deep sleep… and Kilauea not only filled in the 2018 pit over 400 meters in a few years but erupted at 1000 meters elevation and outside the caldera only 6 years after, indicating things have filled faster than expected.

    • 20240606_20240613.png

      HVO released an interferogram of the deformation since June 6, showing the inflation but also the actual graben formed. It looks like the eruption was basically right where the dike actually started breaking the overlying surface but it lost enough pressure doing that to stay just underground further than that. But the very narrow width of the graben shows how shallow the dike actually was, it might have been less than 100 meters deep all the way along, possibly even less. It might have failed to erupt lower because it degassed out of the erupting vents and flowed downhill. If the intrusion had been sustained for a few more days it might have welled out of the ground near Mauna Iki.

      • Image removed and replaced with one with more acceptable size. Please do not link images of excessive size – on behalf of people with data limitations on their links and contracts! -admin-dragon

        • At the same time, this might also be basically an X marks the spot showing where the curtain of fire will be next time. If the rifting at Sundhnjukur is a guide, then its about to get pretty crazy. At least there is no risks to anyone with an eruption here.

          • Based on the tilts and GPS, the current inflation is at the same location as in this plot. Most GPS’s in the region (e.g CRIN, UWEV) show horizontal motion but no current uplift, but CNPK and OULTL do show significant inflation.

            By the way, you can’t just convert a tilt change into a volume. It depends on too many things. But a map like this can give a volume change.

          • Thats why I said approximate, its kind if a coincidence specific to UWEV. It does help to give a rough number, and the behavior of the volcano does line up pretty well with these numbers.

        • This supports the possibility for a Halema’uma’u scenario or something in the SW corner of Kaluapele (Kilauea Caldera). 1971 the SWRZ eruption was preceded by a summit eruption in this area, and the 9/1974 eruption again was in this area, when HVO expected a return of SWRZ activity.


          • That fissure in 1971 was a shallow crack from the old shield of Halemaumau. Now that Halemaumau is a proper caldera of its own I think it could be a long time before that crack system starts erupting again. Actually looking at recent events I think the only eruptions on this crack, which is referred to as the ‘volcanic SWRZ’ on some maps, are all historical. 1823 was obviously a Halemaumau or at least summit drainout. Then was 1868 that was very small even smaller than the last eruption. Then Mauna Iki, and then 1971. Interesting part is that the crack used to go through the caldera to Kilauea Iki, and this trend is where the September 2023 eruption happened. But its all just way too low down right now, there isnt pressure from below like there is a bit further southeast. The eruption in July last year was the best chance to erupt in this way.

            All of the other SWRZ eruptions that are younger than the summit erupted Observatory flows all seem to be derived from vents that are actually part of the SWRZ, even though there have only been 2 observed eruptions of this type. The SWRZ is not so inactive as it seems really, only compared to Kilauea as a whole. I dont think there is a single rift zone in Iceland that is as active as Kilaueas SWRZ. And the ERZ had a gap of at least 54 years between 1868 and 1922, and 82 years to go back to 1840 for a confirmed eruption.

          • In June 2023 there already was a fissure eruption in Kilauea Caldera which crossed the lava lake until the SW border of the Caldera; there was a vent on the Caldera Rim. It showed in my eyes an early tendency towards the SW(RZ), where the intrusion in February 2024 went to. Maybe this SW corner of Kilauea Caldera is able to erupt again.


          • I guess, there isnt really any exact reason an intrusion into the 1919-1971 area cant happen, more just that it is harder to do that than to just intrude from the SWRZ connector directly. Mauna Iki is a bit lower than the current floor of Halemaumau, but barely. There are a few tiny vents from 1919 further southwest but its pretty flat out that way so the elevation difference isnt crazy still. Mauna Iki also formed when Halemaumau was about the highest it has ever been historically probably 300 meters higher than now.

            The SWRZ connector is completely underground, and unlike Halemaumau it seems like magma pressure here is very high, nearly at 2018 level and higher than 10 years ago. So there is a lot more pressure than just the weight of the magma, also the elastic deformation of the rock is a factor. And magma in the SWRZ connector isnt going to be degassed either.

            An eruption in Halemaumau is though very plausible, it will probably happen as soon as it is easier to break out there than open the SWRZ again. But the pattern of deformation is the same as a month ago and now the rift goes all the way to the surface too.

    • Does this indicate that Halema’uma’u location is the probable next site for eruption? In September 1974 there was an eruption both in Halema’uma’u and the western Caldera rim. It lasted for less than a day (comparable to the eruption of June 3rd 2024) and had a fissure within Halemaʻumaʻu and Kaluapele with a short-term lava lake.

  10. RUV reporting that they’re having to resort to water cooling of lava after it breached the defences at Sýlingarfell. I can’t work out the specific location of the breach, and obviously this quite slow moving now, but hopefully it’s not too close to the power plant. My comments always get blocked with links so you guys can check the website yourselves.

    • Lava have incredibley low heat conductivity so it will likey only cool the outer crust of the lava, the cooling effect is not getting in that far, if the lava descides to move in that direction it will just break through, the heimaey lava flowed mostly into the ocean, rather than directly into the town, a direct lava assult woud likey have rendered the cooling attempts useless. Submarine lava flows can move miles after miles because it forms an insulating crust keeping away sea cooling, it will likey only cool the surface. But will make the barrier that exist stronger

      • That’s interesting, thank you for your insights! Slightly ominous for the facilities there though, it does feel like there are only so many times you can raise the fortifications. One just hopes that the eruption cycle changes so that the existing facilities can survive, it’s hard to imagine them withstanding another 3 or 4 eruptions.

      • Yes, submarine lava flows can be up to tens of kilometers long. Water won’t stop lava if it wants to go in a particular direction. But maybe it can slow it down.

      • Water wont stop it at all.. the thermal conductivity of rock is too slow for that .. too good insulating

        • Water doesn’t stop lava flow, but changes the physical conditions, mainly the pressure environment of lava. It supports thick lava flows with more vertical dimension than atmosphere.

      • If the lava moves straight towards it nothing will work, not even the ocean cannot stop a 1000 s of m3 a second lava flood, souch fast lava sheet floods have flowed kilometers out on the reykjanes seafloor when erupted on it, too much low conductivity massive dense hot stuff thats lava thats comming out for anything to cool that quickly, submarine sheet flows flows nearly completely unaffected by the sea cooling due to high eruption rates and lava does have low conductivity

        Cooling a massive Aa wall forms a nice barrier crust yes, but only if the force of the lava flow is flowing elsewhere otherwise it wont work. Even small pahoehoe flows are nearly impossible to cool, as seen with Kalapana and Wahaula visitor center in 1990 s the hoses only cool the surfaces but are unable to penerate into the flows hot interiors, pillow lavas that are submarine pahoehoes can flow long distances being well insulated

        • Yes, it worked in 1973 also because the lava was already pretty sluggish. But if you can cool lava that pools against (and just over) the barrier, that could be a way to make the barrier higher. I agree with you that it sounds like a last resort but Iceland has surprised us before

      • In the video shown in the link Albert posted you can see the lava they’re trying to stop. It’s a slow moving rubbly a’a flow. It would be difficult (impossible) to stop the entire flow by cooling it, but now that there’s already a berm in place to hold back most of the flow, only that small part that trickles over it has to be cooled down, which leaves a much better chance to succeed.

        The cooled down lava also makes for new construction material for the berm. No need for dump trucks when the material moves there on its own. Even if they don’t manage to cool the interior of the flow, the dozers can probably push away the cooled parts to expose the hot interior for additional cooling. Those bulldozer operators are a different bunch. I saw one of them posting a video where he pushed away some still red hot lava with a caption that said something like “I just had to give it a try”.

        If lava flows over the berm during the initial fissure phase, then it’s probably game over. Also, if the berm would break and all the pooled up lava should enter at once, there’s probably nothing to be done about it. In this article there’s a video of firefighters spraying water on the lava:

  11. Joy!! thunderstorms forecast for me today thats basicaly atmospheric volcanoes, generaly a rare things in a cool semi oceanic climate that I live in .. but will likey end up with some boring fuzzy anvil clouds with a flash or two rather than a really strong thunderstorms, CAPE is very weak in Northen Europe compared to tropics and subtropics due to all cool ocean around that moderates and it never becomes as warm as Texas here either

    Bangladesh have megacells now in summer! yesterday there where an overshooting dome thunderstorms cloud in satelite that seemed to be 300 km wide and a cirrus shield as large as UK. I guess its the 45 c summer temperatures and high humidity and Himalayas uplift of moonsoonal wind flow making the skies EXPLODE … I never gets storms like this : (

  12. I overlayed the Kilauea insar on google earth to get some real numbers.

    The dike is a little over 10 km long, depending on exactly where it starts.

    The graben is on average about 100 meters wide and pretty much the same width range along the whole length, so the dike was probably only tens of meters deep in many places west of the 4th fissure. I can assume the lack of strong degassing was because most of that was done at the fissures that did erupt at higher elevation.

    The dike in Danuary did make ground cracks but it didnt make a distinct graben, it seems the magma was a little deeper down. This one was probbaly in the same place but very near the surface. The quakes are offset downslope to the top of the dike so it is very hard to compare based on that, but the interferogram we got in February does suggest the June dike intruded within the area of affect from the January dike.

    Next time I think we get a big intrusion like January, but it surfaces in the same area as the recent eruption. Whether it goes further down the rift or remains intrusive, as recently and in 1974, remains to be seen. But there is also the potential it doesnt make a long dike too, and just dumps the full volume of the overpressure onto the surface. That is less likely, but not impossible.

      • Seems like it. It looks like it intruded into the same place that turns into the Grsat Crack further down, maybe the GC actually went a lot further up but its surface expression was buried in 1919 in this area.

        I think maybe all of the SWRZ eruptions in the post 1790 era were proper SWRZ eruptions then, even the slower ones. 1823 looks like a crack started at the southwest end of the caldera and then turned away southwards to meet the main SWRZ and flowed down that. The crack that erupted in 1919 and 1971 might have been first created in 1868.

        Just going on the patterns today being unchanged from a month ago the same dike as early June is likely to be active again next. Kilauea has evolved a lot since the 60s, its more of a true central volcano now, so I dont see it swapping fissure swarms as easily as it did before 1975. Not until there is too much pressure and it has to break out lower down, then it might go to Kamakaia or it could go to the ERZ.

    • Mount St. Helens is the most active volcano of the 48 USA states and has a broad variety of magma (Basalt to Dacite) and eruption styles (Hawaiian to Plinian). It deserves much attention and love, although it’s doing a break now. But it has the highest probability in the 48 USA to erupt again.

    • She often does M3+ and M4+, completely unrelated to what happens in other corners of Iceland.

  13. Based upon the Iceland Meteorlogical Office (IMO) post, we’re looking at 63 to 73 days time lapse before the next fissure eruption occurs. See . This would be from August 22nd to Sept 1st time frame for the next fissure eruption to occur, and most likely in the same area before.

  14. The lava level in the pond has stayed low for the last 12h. At 5:12:40, a large chunk of the rim collapsed into the pond and revealed a view of the lava surface. It has remained at the same level since the collapse and it seems to be flowing away from the cone at a slow but steady pace. Looking at the cone from the Sandholl cam, there’s not much activity left inside the cone. Looks like it might be shutting down.

  15. Nice photo showing Nyiragongos summit region being covered by ephemeral snowfall, at 3470 meters. And it seems oddly low as a freezing level for being at latitude 1 thats pretty much as warm latitude as it gets on Earth. I guess that snowfall is very rare on Nyiragongo and is a rarely photographed phenomena, I have never seen a photo of the volcano from afar when its covered in snowfall, only seen that for Karisimbi photos. In reailty due to Virunga sitting on an 1500 meters high mantle boulge, Nyiragongos true height woud be an incredible 4970 meters above sealevel, but if placed at sealevel the Nyiragogno cone is “only” as tall as Etna roughly as its true height. Latitude 1 haves a permanent snow level at over 6000 meters with Kilimanjaro just scraping that frost elevation, but infrequent snowfalls can happen at night at lower elevations with more air pressure. Had Virunga been in some of the european rifts it woud certainly be ice bound at high latitude 40 s or low 50 s

    • But Hawaii of course winns the contest as the worlds most monsterious induvidual volcanoes, where edifices grows to the size of small LIP s supervolcanes is acually a good description at least compared to other edifices. That the size of these volcanic edifices and the unique geological enviroment and the biology and addition of 9 to 11 climate zones makes the Big Island without question my favorite Island, so much to see and photograph in HVNP. The great height and size of Mauna Loa and Mauna Kea blocks the trade winds forming one dry and wetside and 11 climate zones results from that combination… very contrasty place and specialy so between Hilo and Kohala desert. The lower Kohala desert between Kohala and Hualalai was incredibley hot! un – hikable even: sourely was 40 c or something even if one dont expect that winter wise in latitude 19 in pacific ocean. Hilo was wet and opressivily humid, althrough Kailua Kona was hotter, hiking Kilaueas lower lava flows was also absolute furnace hot due to basalts dark blackbody solar heating.

      I have always been curious what Hawaii woud look like on the Equator? and if it woud really be anything warmer . There are no volcanic Islands that large or with that morphology on the Equator so its hard to know for soure. Alot of Hawaiis apparence is due to the volcanoes blocking the trade winds creating one dry and wet side. On Equator the trade winds does not exist in most places replaced by the ITCZ thunderstorms belt, so by that definition Big Island woud loose its dry side completely I guess by that factor, making even the Kohala and Kau deserts as green as Hilo and Hamakua coast. The older Hawaiian islands woud face even more severe erosion under the constant ITCZ rainfalls creating wet sides all over

      Warmth is very strongly moderated by the sea surface temperatures, eastern pacific ocean gets very hot, while far western pacific ocean is quite cold near Galapagos 17 c . For Hawaii its about 25 to 28 c in waters depending on season, for Kiribati its 29 c in the sea all year around. In eastern pacific near palau you gets 31 c water temperatures. While Hawaii is somewhat cooler waters than Equator it clearly does not stop Kailua Kona and Lower Puna lava flows getting uncomfortabley hot even in winter … Holei sea arch and Captain Cook Bay nearly had me with a heat stroke in december 2021 D :

      • The lowland lee side of
        Kailua Kona is a blast furnace, but in the dry zone there is There’s a happy zone around 1,000 meters elevation there. During my numerous Big Island tours visited the ‘upcountry’ in the lee of Hualalai and Kohala once. Very temperate climate, none of the sweltering heat of the lowlands, or the persistent warm damp of the windward Hilo side…. lovley place … Waimea looked like a Tasmanian farm rural community …

        • I only went to Hilo and around the southeast but a lot of the higher elevations do look very familiar. Actually, up at Kilauea it was extremely similar, it was pretty cold and being upwind it was very clear and quiet. Never expected to feel so familiar standing a couple km from a place the mantle is exposed… 🙂

        • I dont think Hawaii can be classifyed as subtropical in anyway at all, Kailua Kona is incredibley hot even in deep winter at low elevations, after lunchtime its so hot you cannot do anything … But an Island with 9 – 11 climate zones is hard to classify anyway 🙂 The highlands are much cooler but without much seasons in temperatures either

      • Yes Kilaueas summit region highlands rainforests are a place of awe stunning beauty! the black lava, the ferns, the mossy ohia trees, the steaming fumaroles and its an almost jurassic feel with that steam and lush greenery, its primodial in all senses.. yes very similar to the cloud forests in Tasmania and New Zealand

      • Not soure if Hawaii really woud be any warmer at all on the Equator…the Kona Lee side lower elevations are already quite hot for soure by lunchtime

        But woud be No dryside?

        • On the equater Hawaii would be much wetter. The subtropical climate of the actual position of Hawaii causes a dependency to (northeasterly) trade winds with a rainy east side of the islands and a dry west side of the islands (Ka’u desert).

          The tropical climate along the equator would mean more thunderstorms. A climate like in Congo and Indonesia. This would make the desert to a green hell.

      • Hilo side and lower puna is also immensely beautyful on the windward side, that side is bathed constantly non stop in ortographic rainfall, its so incredibley green and apparently completely overunned by invasive plans and animals, giant rainforests trees rise 200 feet in some pockets, looked alot like Singapore and had a similar humidity- heat uncomfortable index at noon felt like a Sauna, Hilo was very cozy like a a tropical western town. Its likey the worlds most northen place with a true tropical rainforest climate, an immensely green and beautyful place, but clearly being a kind of frankenstein garden where rouge plants from mainland are overunning everything..growth is rapid in the heat and humidity of lower puna. The lower 2018 leilani lava flows are now being overunned by ferns, says something how fast life colonisation is in lower Puna, and is the main reason why Kilauea is so very green despite having the highest lava resurfacing rate of any active volcano. In 20 years Fissure 8 maybe green from space due to lively ground vegitation …

        Had Kilauea been somehow on the dry lee side… the 1500 s shield pahoehoe flows woud be as fresh looking as Kau Deserts rusty pahoehoe today

  16. Can someone remind me what the new links are to IMO sites like drumplots?
    I remember if you edited the new URL’s somehow the pages work?

  17. Quick note: I took the inflation rates of 4 GPS stations, HS02, ELDC, SKSH and THOB and it looks like the current inflation rate is about 63% of the previous rate. This definitely will increase our wait time for the next fissure eruption to occur.

    • I think you need to look at the trend a few days after the current activity comes to a full stop. Currently, some of the magma goes to feed the eruption and that could influence the inflation rate.

  18. How would Katla look like without the glaciers? Would it host some kind of Geysirs or hot springs? Some earthquakes there are occasonially caused by hydrothermal events. That’s unlike dry volcanoes which don’t do water/steam activity.

    • Probably a lot like Okmok or Askja, its kind of between those. Its more explosive than Askja but the caldera isnt an ignimbrite caldera like at Okmok. Eruptions without the glacier might be similar to those at Hekla, being mixed effusive and explosive, although probably less predictable in location.

  19. I don’t suppose someone with more insider access than me might trouble themselves to ask mbl to give the focus knob on their Hagafell camera a good twist or two? 😛

  20. Its not every day you see a tiltmeter that looks like this… +50 microradians in a little over 2 weeks, and 35 past the trigger of the last eruption. Seems like the next eruption will begin with some force behind it

    • Yes, it must be among the top values ever recorded by UWE. I do know that throughout the Kilauea Iki eruption UWE recorded some 70 microradians of inflation in just about a month. But after that one time this might be the highest ever. In late 1960 it got to 40 micro radians per month, and inflation in between some of the 1969 Mauna Ulu fountain events also got to around 40 microradians per month at times, but this beats both of those.

      • Yes if this keeps going for much longer there is going to be something .ajor going on. Its easy to forget the last deflation that shows was an actual eruption and outside the caldera to boot, yet looks minor in comparison. ~50 million m3 of magma in a week, even 1/10 of that is about twice the rate of Pu’u O’o.

        Maybe all of that hypothesizing about the Pahala Swarm and immense magma storage there, and it supercharging the output of Kilauea for years of much longer, it wasnt so fanciful after all…
        Its fortunate this has gone southwest, it might take the worst of it that way instead of erupting in Puna 50 years earlier than expected.

        • “Its fortunate this has gone southwest”

          I don’t think southwest can channel the supply for long, though. The southwest rift zone is an insignificant part of Hawaii’s total productivity. The lava production goes into Mauna Loa activity; Kilauea caldera filling, or when rifts are down summit overflows; and Kilauea East Rift zone activity . I don’t think there’s any evidence of the Southwest Rift Zone ever taking up the supply for a long time. There are no large shields after all (biggest thing is a ~one-year eruption like Mauna Iki or Kamakaia Waena), and it’s not as long as the ERZ nor does it have the very high spreading rates of Kilauea’s upper ERZ. Having two successive dike intrusions in the SWRZ is already unusual and probably only possible because one was deep and the other was shallow, but they have probably filled much of the rifts built up extension already.

          I’m not saying things will go for Lower Puna though. UERZ activity alternating with summit eruptions is more likely for the time being, maybe even another Mauna Ulu or Pu’u’o’o.

          • I should add that the Southwest Rift Zone below the Kamakaia Hills is sort of dead. Yes fissure eruption can sometimes happen, probably from shallow dikes following the Great Crack. But are rare and not large, deep dikes. The south flank of Kilauea is not mobile west of the Kamakaia Hills, that can be seen offshore where the flank thrust dies away (about Kamakaia) or looking at the aftershocks of the 1975 and 2018 earthquakes. It’s unlike the ERZ where south flank moves away from the rift to as far down as Kapoho, and that’s only at present because in past times much of the Puna Ridge was also pushing the flank away.

          • Could the present inflation lead to a major fast caldera filling eruption? Imagine an eruption like 2020-2023, but on high speed, order and with large volume.

            The movement of Kilauea’s summit GPS stations show that something must accumulate between UWE (moves north) and OUTL (moves south) station, while nearly all summit GPS stations go significantly up currently. Maybe we get a “Boss Eruption”? An eruption that dwarfs all known historical summit eruptions … like the 1950 Mauna Loa eruption for Mauna Loa but in the summit area.

          • To be fair, if you could go back and tell someone in 1983 that the little spatter cone east of Napau that keeps geysering every frw weeks would still be erupting in the late 2010s, and followed immediately by a caldera collapse, they would look at that and say youre crazy. Kilauea has done a few ‘firsts’ in the past century. I agree that the ERZ will probably take up alot of activity in time but the SWRZ is still long enough, Kamakaia Hills is as far from the caldera as Pu’u O’o and similar elevation, the recent eruption is similar to Mauna Ulu elevation. Maybe a 2018 needs the ERZ but a satellitic shield could form on the SWRZ, a real one that is.

          • Pu’u’o’o does have the precedent of Kane Nui o Hamo, and 2018 the precedent of Puu Kaliu and other large LERZ eruptions.

            Kamakaia is more like the Puna Geothermal Venture than Pu’u’o’o. It’s the tip of the magmatically active SWRZ, which the last two dikes rifted entirely from bottom to top. Spreading is not as fast in the SWRZ section as in the upper ERZ and summit, and even the spreading that does happen in that area, is divided between the SWRZ and the Koae Fault System that is supplied from the ERZ. While the ERZ takes maybe half of the intrusive volume that belongs to the SWRZ section, on the surface it’s the summit that takes up much of the lava volume in that area, due to summit lava lake overflows like the Observatory Flows which flood the SWRZ.

            If the SWRZ acts up again, I’m going for a Halema’uma’u dike that reaches towards Mauna Iki, maybe even a Keaiwa-like event fed from the summit rootless lake. Otherwise, I think activity in the near future will be dike intrusions in the Chain of Craters (maybe with small eruptions), or eruptions inside the summit caldera.

        • I would tend to suspect the Pahala swarm is pretty old and just more active now from a surge of supply. If not though, the Puna Ridge is the obvious place for a Laki-type eruption in Hawaii…

          Seriously though, Kilaeua has formed calderas hard to believe didn’t involve eruptions dwarfing 2018. Most obvious place for that is out on the Puna Ridge since enough elevation drop for utterly catastrophic drainout. In a certain sense its hard to believe a system as big as Kilaeua can’t form black swans the way the various big Icelandic systems do every few thousand years. I wonder how much is lost to Kilaeua’s regular redrawing. But like the Powers Caldera might have had a volume nearing 20km^3. Was it actually formed in a thousand years of more explosive eruptions? Or was it formed and then it was big and deep enough to catch a lot of water and make more waterlogged eruptions?

          • There is a map in this Volcano Watch article showing a very large lava flow, possibly Laki-sized:


            There are some lines of evidence that suggest Kaoiki Pali may be the rim of a large caldera from around the start of the Holocene, that collapsed the whole SWRZ. And of course, some of the eruptions that shaped the current Kilauea Caldera were larger than 2018. For example, I estimated 1.5 km3 for the Puu Kaliu eruption based on lava delta size, which was also very intense, with 500-meter fountains I seem to remember, and was probably to blame for a caldera collapse around 1500 AD.

          • That was my thoughts too, that 2018 was a huge eruption but the 2018 collapse didnt involve the whole summit. So clearly the volume of eruptions creating the major caldera is more than 2018. Although 2018 was probably about as big as things can get without extending offshore to some degree.

            Regarding the SWRZ still, all of the big ERZ eruptions are around 1000 years old or less. At least talking about lava shields. Before that it seems to have been more of a traditional rift zone. So changes have happened at Kilauea recently. The SWRZ might be smaller but its structurally the same as the upper ERZ, and is currently a lot more active. The ERZ seems to be unprepared to activate further down while we have seen two SWRZ intrusions now this year, maybe it is unusual but rather than it being more of a random chance it looks more like a trend likely to continue.

            I guess now its a bet, another SWRZ intrusion and eruption, or an ERZ eruption. Neither is exclusive of more caldera eruptions so I wont count that 🙂

          • The SWRZ is more closely related to the summit. If the summit gets an intense voluminous eruption, the SWRZ may get some “by-products”.

    • Yes looks like the volcano have gone into an era of super high supply, the word supervolcano does fit Kilauea rather well even if its not a VEI8 system, the magmatic influx and long trem output is quite unique, pulse of magma supply .. hopes for long lived tourist activity soon

    • Disgrace it was not found by Nordics in terms of natives meetings with the outside world in 1700 s .. I doubt the contacts woud have resulted in any better situation than other westerners in early imperialist era, But a Danish Hawaii instead of a british discovery woud result me being automatic citizen there 🙂 If it was not given to US or other countries. But I will have to be content with Iceland even if its not as good in volcanic activity per induvidual volcano as Kilauea are

      But best woud be Hawaii as an independent polynesian state thats probaly what the natives wants

      How well open, opened is the SWRZ connector now? last time the summit magma pressure forced itself through there, maybe it coud do that again soon, not alot of So2 output during the last SWRZ eruption perhaps was degassed winter magma mixed with new summlt magma

      • The seismic center of activuty this year, and zone of strongest uplift, is at the start of the SWRZ connector. The ERZ connector quakes but doesnt seem to be inflating and Halemaumau inflates but is quiet, both are shadows compared to the SWRZ connector…

        So, basically, its very likely for another SWRZ eruption. The one two weeks ago already breaks all the trends, there has never been a repeated intrusion on that rift within a single episode if activity like now. Every time that has happened that I am aware of, be it Hawaii or Iceland or elsewhere, we get some major resurfacing… This is a rifting event, like happened on the ERZ in the 60s, and that created Mauna Ulu after 10 years.

      • As an interesting fact, it’s thought that the Spanish (Juan Gaetano) may have sighted Hawaii in 1555. They called Hawaii Island “The Table” because of Mauna Loa’s shape. So it may not have been a British discovery.

        • Although, of course, it was a Polynesian discovery much earlier than that (1100).

          • Interesting, I knew the Spanish made some Pacific expeditions, and had a long control of the Philippines as well as some direct trade from there to Mexico at least I think that was a thing, but Hawaii is further north than I would have expected them to go. They just missed out on Kilaueas caldera forming then. 🙂

            I also recall something about the 1100 rough date being the date the Hawaiians found it but maybe not the first time it was ever found full stop, with there being two waves of settlement, I guess 3 counting the British. Unless that theory has been debunked.

      • Mauna Loa is indeed a magnificent sight seen from afar! a broad… dome snow capped with white stretch over the distant horizon .. towering sky high over the trade wind cumulus, what captain cook saw as well the Native settlers a 1000 years ago earlier must have been magnificent, seen 10 s of km from shore must have been a magnificent sight.. the sheer scale of that triumphs any other volcanic edifice for soure…

    • The two year graph shows the change of activity in June 2023 well. Until then inflation was more or less steady, while after June 2023 the deformation looks like a toothed saw. I have the feeling that we did enter a different period in Summer 2023 with more instability of Kilauea’s behaviour:


  21. I personally think , This means the lava is also at massive heights..the biggest problem from yesterdays overflow of lava, so close to Svartsengi, is that the Berms there are now at massive heights.
    They will win this round but what is worrying is that the next eruption may once again send really fast flows of superheated lava once again in that direction. That will be a major problem, as the lava flow in that area is currently at the full height of those berms, and with a very limited area to work it will also causing logistic problems. in building the berms higher
    I know they are currently seeking areas to build a new powerplant but the big question is, how long will it take to get one built and running?

    • Looks like Goma is in for another lava flood in the near future

  22. Steam seems to be coming from a bigger area than where the water is going?

    • *that should be already erupted lava may continue to flow …

    • That’s a better cam than the one I just linked, showing the same vent, which looks to be maybe 100 m north of the power station berm. Which explains why there are so many vehicles going back and forth at 1:30 am.

      Here’s a Google maps location which shows all those pipes. The vent is maybe 300-400 metres NE from the pipes.

    • Now 2 am and the two white cars have headed off. They had a look at the fumarole just on the other side of the berm, then one went up the road to about 50 m from the vent to check it out. Now one has driven off towards the power station and Blue Lagoon and the other has headed south towards Grindavik. Hope the guys in the cars are getting overtime!

      Just after 2 am and a yellow colored van is checking out the vent, and now to the fumarole. If I had to guess I suspect it is the contracting company deciding whether they need to get their machinery out of the way. The van has gone off to the power station for a chat with whoever is in charge.

    • Just shy of 3 am and the yellow van has arrived again from Grindavik. They headed for a point almost exactly between the vent and the fumarole on the edge of the berm. They’ve dropped off something maybe a metre in size, some sort of instrument package I’d guess. Then drove down to the power station command HQ at the turnoff from the Grindavik road for a chat.

      The vent seems to be declining already, it may not be doing much by breakfast-time.

    • And that’s it folks. The tiniest ever Icelandic eruption is pretty much over! Whew, the Blue Lagoon survives yet again.

      At its height the small fissure, which was maybe 30 m long, was doing respectable fire fountains around 5-10 metres high. Which I could estimate from the size of the nearby emergency vehicles. Still plenty of steam and gas but not much sign of any more lava.

      • This was not a fissure and there were no fountains going on. This was a stream of lava overtopping the berm. If you go to that livefromiceland link and check the timelapse videos from the last two days, you can clearly see what’s going on. In the night it might look a bit like fountains, but it’s just rising steam that is backlit by the incandescent lava.

        • Tomas – I was watching with my mk 1 eyeballs. The whole thing was pretty brief but I saw fire fountains around 5 or 10 metres high over a length of 20-30 metres. As I said there were vehicles close nearby so that gave a useful scale to the size of the eruption, such as it was.

          It was not lava overtopping the berm because there’s no way that can cause a spray five or ten metres into the air – certainly not when the central crater was declared dead by IMO and others yesterday.

          Merlot’s post at 15:28 shows what it looked like before the small eruption. I’d checked the webcam I linked, which was fuzzy, that was at 1:32 am. Something looked to be happening, I didn’t know what. Randall put up the other webcam at 1:20 am, which I thus checked – it was much clearer. By that time there were obvious lava sprays occurring under the smoke. By 2 am there were the fire fountains. But by 3:30 am it was all over.

          It looks like the small amount of lava joined the general lava flow or tube, because there was a slight increase in the incandescent flow just to the NW of the Grindavik road. But the total amount erupted was very small. Smaller than the fissure on the edge of Grindavik that destroyed those two houses.

          I can assure you the Icelandic authorities were very interested in what was occurring given the number of vehicles zipping around in the middle of nowhere at 2 am. It was fascinating to watch it – thanks to RUV and Live From Iceland for their cams!

          The weather has now arrived so you won’t be able to see anything.

          (I live in Australia so had the advantage that it was all happening about lunchtime for me.)

          • If you go back one more day and check how it looked then, you will find that there was a flow of lava coming over the berm in that exact spot. Machines then dumped material on top of the flow, creating a temporary dam. It was this dam that broke and allowed the flow to start again.

            Even if the eruption has stopped, lava will continue to flow for a while. Under the solidified crust it’s still molten and it’s downhill so gravity will do its thing.

            I can with 100% certainty say that there was no new fissure in that spot.

          • Is this what you saw?


            It looks like the third over-spill to me, with the steam reflecting the glow from it. But it is bigger than I would have expected. Could be more visible due to poorer light conditions over night and/or more lava was going over following cooling the other two spills.

          • Close. It was a bit more active than that at peak. You could see actual fountains. Two or three centres along that line.

            A vid from that cam over the period would be excellent, but I don’t know how to find that.

          • Sounds like a rootless vent, lava being thrown up by steam erupting through it from below. So its a lava fountain but not a true eruptive vent with a deep connection. I havent actually seen this supposed activity but the amount of steam coming from the area is a clue.

            Its not a deeper vent though, otherwise a major swarm associated with a dike intrusion would have been evident.

          • Ok, I went back and looked at it, the steam is water being sprayed on the lava, and the bright glow is reflected. I saw no lava fountains

          • Yes, they are spraying water. This stream has a very nice close-up.


            It’s still possible to rewind, but it will soon fall out from the 12h cache.

            Basically, they are using this overflow to experiment with different methods to stop it. I don’t get the impression that they are actually worried about it. The big challenge will come during the start of the next episode.

        • Ok sorry. you are absolutely right. I stand corrected, RUV has a story about it today:

          New defence wall and more water cooling as lava flows (21 Jun)

          Three lava streams are flowing over the wall, according to Elísabet Pálmadóttir, a natural disaster specialist at the Icelandic Meteorological Office. However, it seems that the flow in the smallest stream has slowed down after lava water cooling was applied last night.

          By 2am, one of the lava streams had been mostly stopped, but thick and glowing lava was still pouring down. Sources say work has begun to build a new defence wall inside the one over which the lava flows, to prevent lava from reaching important infrastructure in Svartsengi.

          Must have been a miserable night for the team of firefighters. I am surprised though about the source of the lava since IMO had said the eruption had stopped.

    • Jupiter is souch a strange kind of disturbing world with no solid surface at all, the dry cloud free atmospheric hotspots like the 1995 entry site are specialy terryfying, there you have a clear blue daysky ( in the troposphere ) due to rayleigh scattering, no clouds… yet you woud still see a horizon of Jupiters own shadow, Jupiter itself below your feet woud look dark and non transparent perhaps a dark hazy olive color, while the dayskies above are clear and blue … thats strange stuff to think about! and the deeper you go the paler the skies becomes due to more scattering , perhaps turning dark red 100 s of km down… until the pressure gets too thick to allow you to see sunlight

      Most places on Jupiter haves clouds condensation so woud be similar to a cloudscape in Earths atmosphere … being in a plane and looking out the window

    • Nightmarish sigth…

      Woud be fun to see the Jovian Moons rise a morning, seen from Jupiters tropospause ( If you where down in the atmosphere) Jupiters shadow woud be visible too that it cast itself on the upper atmosphere and the horizon woud be incredibley distant. The jovian ammonia cirrus, cirrustratus 50 km below woud be a smooth beige – white silky plain, going for ethernity litteraly. The morning skies maybe a pale pleasant or just blue.. the air density is not great as far up as this, so woud be very dark blue at noon when scattering is least, but more color at evening and morning. It woud be a very earthlike experience at least visualy the jovian atmosphere and very disturbing knowing there is No surface at all below your feet.

      I often roams Jupiters skies in my daydreams in a gigantic hot hydrogen zeppelin, think hindenburg/ graf zeppelin but on steroids, and I woud best like it old and steampunky : ) rusty copper, brass coloured with lots of rivets visible in it, the retro golden gondola cockpit woud be a spectacular panorama over the jovian cloudscape. The whole rusty retro Zeppelin thing woud have to be absolutely gigantic to have any chance to provide any lift at all, as Jupiters atmosphere above the ammonia cirrus is not very dense, and hydrogen is very light and gravity is high, having it painted with Vantablack coud help it with solar heating and bouyancy, but then it woud be just an ugly pitchblack thing and not steampunk classy. It woud have to have a very complicated extra heating mechanism to allow it to float. Lower down in the cloud layers and below the water clouds it woud be easier with bouyancy as the atmosphere is much denser there, but visibility woud perhaps not be good at all as you are below the 3 cloud layers, and if struck by a lightning bolt thats 1000 times earths strenght the whole thing coud be history. The cold in the upper atmosphere woud suck too

      Suicidal project anyway .. getting there and deploying it and the logistics are Impossible and Impossible to get out later with that gravity well of 2,4g unless the Zeppelin haves an nuclear, fusion powered escape rocket pod

      Rather bottomless is a real definition at Jupiter! as you look down you may see a altocumulus cloud field each cloud lit by the sun, below in the clear gaps there coud be another cumulus field miles below the upper layer looking hazy and less bright. Its likley possible to see 100 s of miles down into gaps, but since sunlight cannot penerate or scatter from a clear jovian depth of view ( as you look down into a clear area into the gas giant ) it woud be an unsettling dark hazy gloom. But clouds woud be very reflective and earthlike and the skies above you woud be blue like Earths dayskies, beacuse of hydrogen that woud scatter into blue, but Jupiter itself woud be a dark gloom and a hazy horizon providing No reflective clouds in a drier area.

      Rather disturbing 😳

      Gas Giants are hellpits and not any tourist destination

      • Albert are these suggestions correct in terms of light physics? .. stinks that the 1995 probe had no camera at all….

    • So Galileo didn’t see the Great Red Spot?

      According to Wikipedia one Jupiter year equals 11 Earth years and 315 days, so appr. 11.9 years. With this relation the Red Spot has existed for 16.8 Jupiter years 😉

      • It also spins in 10 hours not 24, so there are around 10424 days in a year on Jupiter 🙂

        • 10 hours? That must be a unbelievable high speed on the surface. The earth does 40,000 km on the equator in 24 hours, 1667 km/h. Jupiter does around 426,000 km in 10 hours, so with 42,600 km/h speed. This would explain the strength of Jupiter’s Red Storm, because the gas atmosphere reacts strongly to this speed. It is like a xxx-Super-Tornado or Super-Hurricane

      • Galileo never did. The spot was discovered by Cassini, but this new study suggests it was a different storm to today’s red spot. Not certain: there is a drawing from 1710 or so which does seem to agree better with the current version

    • Just as otherwordly woud be the edge of a humid cumulus field on Jupiter where humid air condensate, but when it borders on a superdry downdraft.. its an lumpy white sunny cumulus plain that ends into a ”dark hazy plain” with no cloud condensation.. kind of unsettling to imagine..

      Visibility in cloud free areas on Jupiter are purely ruled by rayleigh scattering and pressure density of the atmosphere, Jupiter itself is an untransparent mass so will appear as a dark grey plain I guess ( with a fuzzy horizon ) the dayskies above will be dark to very pale light blue … at 0,1 to 7 bars pressures

      This is very strange stuff… and is kind of disturbing to imagine

      • ” dark grey fuzzy plain below a blue daysky” is that correct in a cloud free arera on Jupiter? Im using my basic knowledge of physics

    • Hopes the summit erupts soon…will be something soon when the supply is as very high as this

      • High tilt angle means there is significabt pressure. Wherever it happens, the next eruption is going to be very intense. I think lava fountains taller than the caldera rim are a possibility if it does go within Halemaumau.

        The other key part, if it doesnt break open a whole new rift, then the timescales of warning are going to be short. Like, it could erupt in 2 hours kind of short… SDH is still rising at a high rate too, just that its scale has blown out to very high increments, but it has tilted by even more than UWEV…

        The supply rate at present is probably equivalent to over 1 km3/year long term. Its not going to stay so high but who knows how long this will last. Every eruption since the start of 2023 has been followed by an exponentially faster recovery and a very high rate of deformation and inflation. The stations south of the caldera have all uplifted at such an enormous rate they have recovered 90+% of the 2018 drop in less than a year at their respective locations. Things are really going crazy just staying underground just yet.

        • The rise of inflation coincidenced with a rise in seismic activity since 17th June:

          Inflation rises with soft small DI events (D smaller than normal):

          It looks like the volcano is pumping …

      • The eruption in September was east of the deep pit and lava lake but it was also on the trebd of the fissure swarm. Its also unclear what the intrusions for the vents under the lake looked like, at least after 2023 started maybe all of the eruptions followed the fissure swarm and not the ring faults.

        • While the eruption in June 2023 showed a first SW trend, the eruption in September 2023 began the trend towards voluminous events. It was larger than any eruption since 2020. It was succeeded by the more voluminous intrusion in Jan/Feb 2024 and may be succeeded by a even more voluminous summit eruption next. Could we get something like the ‘Ailā‘au eruption, but in a different direction and with a shorter time frame? Something like Pu’u O’o on the summit?

          A danger of potentially voluminous summit eruptions is, that they may choose lava directions that traditionally were uncommon. They could reach locations that previously were thought safe. F.e. the southern summit area.

          • I thought that back in 2022 it might keep going at the summit, especially after seeing it in person. But now I doubt it, the volcano basically stopped erupting when the lake got to near 900 meters elevation. It happened to be when Mauna Loa erupted but I think that part is a coincidence.

            Every eruption in 2023 onwards has been relatively small volume and short. 2020-2022 were slow and voluminous. The total volume erupted after 2018 is about 0.2 km3. The biggest eruption volumetrically was September 2021-2022, while the fastest was a year later in September 2023.

            To get a summit overflow would need the rifts to be completely inactive so it all goes out the top.

          • I believe we can sum up the period December 2020 to June 2023 as a distinct “Caldera Filling” period, that can be distinguished from the “Crater Lake” period 2019-2020 before and since summer 2023 a period with episodic random events which each bigger than the previous one. The SWRZ eruption of June 3 2024 is for me not a real “eruption”, but a small part of the voluminous intrusion in January/February which accidentially erupted.

            The currently major inflation supports the visible trend of increasing quantity and rate of events since September 2024.

  23. So my question is: How does Kilauea go from where we are at now to an Observatory shield and an ‘Ailā‘au eruption regardless of how long it takes? What causes the rift zones to close up so tight that intrusions/eruptions can not occur, for the most part?

    • Maybe it’s going to begin a bit like Pu’u O’o 1983 with a spectacular “Curtain of Fires” fissure in the Caldera, which later changes towards a more steady effusive activity.

      • That is what it did in September, but that stopped, I think the pressure to erupt at the summit is now about equal to the pressure required to erupt on the SWRZ.
        The other factor though is that an eruption in the caldera will drown itself and the lava lake is fluid but degassed and very dense, little chance an eruption can stay open through that, and so far that has held true. An eruption on the SWRZ doesnt have that problem. So I see a longer eruption being outside the summit.

        • The SWRZ deflated much more on 3rd June than it erupted. It looks weak now. Today UWE tiltmeter shows deflation, but SDH and IKI inflation. Is magma moving east? This would increase the probability for a big summit eruption or a series on the “Chain of Craters Road” (f.e. near Luamanu Crater like July 1974).

          • SDH shows the start of the SWRZ, it is inflating again and rapidly, it just has a blown out scale so looks slow.
            Problem is the only active GPS on the SWRZ is KOSM which is either in the June 3 graben or imediately adjacent, you can actually see it just downhill of the fissures in the HVO videos. So I doubt it will be of much use now.

            I think the next activity will be in the same area as June 3 or nearby, its an open rift, and it also goes to a lower elevation than anywhere close to the ERZ connector. An intrusion from the connector to the middle ERZ like in 1968 is not impossible but the summut was filled to around at least 200 meters higher when that happened too. I think it is more likely that the ERZ bend at Mauna Ulu opens and we go from summit to middle-lower ERZ directly and skip the Chain of Craters area completely. So maybe another decade of summit filling and SWRZ eruptions then it rushes down and erupts a little east of Pu’u O’o. Maybe making another shield, and with another 2018, or possibly just a total caldera. But not until the 2030s at least.

    • We had the speculation that it had to do with collapses of the Chain of Craters damaging the ERZ plumbing. The last time this happened was in 1790 and may have led to low East Rift Zone activity for more than a century. It did not lead to an observatory Shield, But the caldera did briefly overflow at some point in 1919-1921 after 100 years or more of almost continuous lava lake activity.

  24. Remember when you were a kid, playing in the dirt, with your bulldozers and dump trucks, moving stuff around, playing with the garden hose, or messing in a little stream, damming it up with sticks and mud, seeing where it overflowed. It seems to me that the gangs operating the heavy equipment around Grindavik are re-living their best childhood, though with crushed basalt and red-hot flowing lava just to keep it interesting.

    • The efforts at the power station berm are Tonka toy heaven!

    • That’s in the middle of the lava field, well outside the berm and a bit further downhill from the place where it overtopped the berm. No machines have been playing around out there.

      This perfectly demonstrates the dangers of new lava fields. The interior stays molten for a long time and beneath the hardened crust lava is redistributed by gravity. The lower parts of the field will inflate and sometimes you can get small breakouts on the surface, like we see now in the webcam. The upper parts of the field will be partially drained, and here lies the real danger. Under the crust there will be cavities, tunnels and caves. In places, the crust will be too thin to support your weight. If you step through the crust you will be badly injured or die.

      • I had another look at it. It’s actually not in the middle of the lava field. It’s the a’a flow front that’s still slowly advancing. It’s running on top of lava from one of the previous episodes.


    lava keeps filling Nyiramuragiras caldera, ( Nyiragongos sister volcano )been some big surface flows recently, looks like lava have risen again forming a lava lake that overflowed its spatter berms “walls” last time it was a large lava lake there was in 2023 when the whole caldera overflowed, that lake may have cooled and crusted over a bit, but now its vigorous again. Explains the strong sulfur plume seen in windy app there, the lava column in the system can only build so far before it drains itself in the rifts

  26. Apparently, the website might’ve messed up a little bit while the UWE tilt was deflating rapidly. Most of the earthquakes are somewhere on the Upper East Rift zone. Preping for a future eruption?

  27. Recovery of Sundhnukar looks slower this time round. I wonder how long it can keep pumping out that level of eruption.
    At current rate to reach the last eruption’s magma run point it will need to refill until the beginning of September.

    • Andy, I agree that longer time is needed, last of August at the earliest possible and probably September.

      • Has the slow decline of the Fires Series begun? If so, the next eruption will begin with smaller intensity than the previous one.

        Maybe the Series will over after one year in November/December 2024. Then we might have to wait for years until the next begins.

        • Would think it will only be longer intervals between eruptions, not less intensity. If anything longer intervals would result in stronger eruptions as the rift can cool more and hold pressure, at the extreme it might even result in a new dike entirely and abandoning Sundhnjukur.

          At least based on the eruptions in the 1200s, its unlikely this sequence is about to end totally yet. Eldvorp seems to have formed in a similar way to the new eruptions, fast fissure eruptions and probably at least a few of them. But Arnarseturshraun is offset and it formed pretty separated, erupting in 1240 where Eldvorp might have been years or even several decades earlier.

          I guess, if Svartsengi really is starting to slow down, it might ve worth watching Fagradalsfjall. Svartsengi inflated in 2022 between the first two Fagradalsfjall eruptions, so they do seem to be able to act together. Right now it is all going there again but it might go back to Fagradalsfjall after, and perhaps return to Svartsengi again after a period of quiet there. They do seem to be properly connected, compared to Reykjanes and Eldey which are related to each other but seem independant of Svartsengi at least right now. And Krysuvik which is doing its own thing and will likely erupt in the next 20 years regardless.

          • The inflation is smaller now than in April, when the previous eruption ended:

            With each eruption the growth of inflation reduces from around 20 million cubic meters per month in November to 10 million cubic meters per month in April and likely even less now. The June eruption occured when the intruded volume was around 20 million cubic meters. If we assume for now an intrusion of 5 million per month, it would take four months until the next eruption. But if the tendency towards smaller inflation continues, once there will be a zero inflation and maybe the end of the eruption(s) temporarily.

            The same eruptions we’ve had would likely be noticed and noted differently during the Medieval Times. We’ve some data written then, but it’s unclear how complete they covered the events. Minor eruptions may have happened without written record. Hekla likely received more attention 1206 and 1222.

          • Last days Krysuvik’s system has shown some earthquakes. Today Kleifarvatn has had four quakes, on Saterday Blåfjell had a M 3 quake. Fagradalsfjall and Keilir have had quakes, too. Fagradalsfjall’s deep magmatic system may feed Krysuvik as well as Svartsengi partially.

            The quakes show that unpredictable volcanic events may happen elsewhere around Fagradalsfjall in near future.

    • One more note, a contributor for Geologist Shawn Willsey sent in a prediction chart, spreadsheet model, quite well done and shows that the earliest possible date for a new eruption is mid Sept, with the latest almost in November. Shawn talked about this spreadsheet some.

  28. This late afternoon the dirt trucks are rapidly building the rampart or berm, but extending it to the north east. Is the goal here to reach the nearby hill with a yet higher berm, to keep the future fissure eruption from breaking through? Has anyone seen comment in the Iceland media on today’s activities? See

  29. Each reinflation post-eruption is slower. The fastest inflation was leading up to the first actual eruption. Last time was the slowest even if you ignore the days when it was still erupting at a lower level. But that isn’t an unmitigated good in the sense that the size of the events is going up at the same time. This eruption was the largest of the 5 so far…

  30. It’s strangely addictive to watch the machines as they work on raising the berm. Two large bulldozers go back and forth at the bottom, using the claw-like ripper attachment in the back to break up old lava into smaller pieces. Then they use the blade to push the loosened material into a pile that a huge excavator then loads onto the never ending stream of dump trucks that bring the material to the top of the berm, where a third huge bulldozer pushes it in place. I counted five dump trucks in constant motion. The whole operation is like a ballet of large machinery.

    Every now and then the camera pans around to show the surroundings, and then it goes to check on one of the fulmars nesting up at Thorbjörn before returning to the machines.


    New thermal and visible imagery of Nyiragongos caldera in two links: looks like we haves a huge spatter cone in the middle there filling up the caldera with lava overflows from it. This is rather very similar to vesuvious effusive 1913 – 1944 activity with slow pahoehoe and overflows from a central spatter cone filling it up. Looks like we dont have a massive lava lake like last time, because the really bright pixel suggesting erupting lava is smaller, so its a smaller lava pond inside a growing spatter cone. This spatter cone is still likely rarther very large, looks much bigger than the permanent 2016 – 2021 spatter co vent beside the past lava lake and the magma column inside is likley convecting due to present of constant plume. With a narrower lava column its perhaps possible to fill higher than the past lava lakes, and past prehistoric times have had lava overflows at the caldera rim

    • I remember seeing some pictures from the early 2000s showing a similar situation, but that turned into the big lake of recent years anyway. Might just be that the conduit isnt wide enough to convect calmly so it is more stirred up and builds up a cone.

    • Might also be easier to take screenshots and post those as images on imgur, that site uses a lot of data when you open it in a browser… 🙂

    • I wonder if it’s just overflows or the whole thing is a rootless lake. A very important difference for hazard concerns.

    • Nyiragongo is a small and strange volcano for soure… The resolution is way too poor to allow us to identify if this is a rootless lava pool like 1980 s or a constantly open spatter lava lake cone filling the crater ”if Nyiragongo is doing a vesuvious 1929 ” there been thick smoke since at least late 2022 so I think we haves an open vent. Nyiragongo is so pretty with that steep cone and lenticular clouds that glow red at night, but the crater is too large for me to call it a ” perfect mount doom analouge like Shishaldin or Pavlof” but its close enough, and knowing how very twisted and feared Nyiragongo is as a place in local culture … I can give it the name ”Africas Mount Doom” anyway

      But the real boss is Kilauea .. with an orders of magnitude higher magmatic influx monsterious for soure, yes I hopes for a New Puu Oo like shield era later when the ERZ opens up lower down, seems un avoidable with a new shield building phase at Kilauea when its magmatic supply is as high as it is now. ERZ is of course not fully closed, just somewhat shaken by 2018 and the deeper stoorage melt parts are competely unaffected so there is just a matter of time before the magma can flow again between the summit stoorage region and the ERZ plumbing systems which souch high supply

      • Nyiragongo seems to be the top of a massive system that mostly stays underground at least at present. The emissions and heat suggest an immense flow of magma under it but doesnt get to the surface much. Seems the opposite is true at Nyamuragira, a little less perhaps to start with but most of it escapes. Maybe Nyiragongo is a rifting volcano in development while Nyamuragira isnt.

        I think to be honest a shield eruption east of Pu’u O’o will not necessarily be a return to the ‘good old days’. Heiheiahulu shield in the relevant area seems to be less of a pahoehoe shield and more of a paroxysmal vent that had a minor late stage slow eruption stage. Its about 1 km3 of a’a and pahoehoe sheet flows to the ocean, with a tube fed flow at the end, and then a fissure eruption downrift a bit south if the 2018 vents which also evolved into a tube fed flow.
        So possibly the distance from the summit will interfere with the continuous flow, and result in an episodic eruption style that could send fast flows a long way.


        Yes lots of gas from Virunga there is always constantly an enromous cloud there so there is indeed lots of magma degassing underground, here is todays sulfur cloud from Virunga in this link, only other area on planet that had souch a constant gas sulfur pollution in windy was Hawaii 2011 – 2018 when Puu Oo and Halemaumau was in co eruption state. There are new photos from Facebook from residents around Nyiragongo showing a rather frigtheing nightgow again and a robust steam plume, Nyiragongo and Nyiramuragira are not very big above ground but looks like as you say there is huge forces underground, they are one of the worlds top gas emitters

        • Yet it does not show up in Earth Nullschool I finds Windy far superior, a few months ago there was an enormous sulfur plume over the entire central Africa in Windy Progran much more than whats normal and that was centered over Virunga – Congo.. ( its disgrace that I did not made a screencut ) so got me thinking if Nyiragongo or Nyiramuragira had some kind of paroxymal summit events, due to a local war this year, and poor moniotoring and the ever present Cumulonimbus clouds in Virunga resulting in poor visibility.. a really scary summit event in the two volcanoes may have been unseen. Nyiragongos and Nyiramuragiras crater terraces and green upper flanks does not look sprayed with tephra at all so coud be just the opening of an fully open conduit with passsive massive degassing when that happened

      • Well, I was thinking the whole thing might be a crusted lake because the temperature is very homogeneous throughout. But this is hard to know. Even with an image of the crater, it would be hard to know if it’s molten under the crust.

        • There seems to be a spatter cone in visible imagery where the smoke plume is, but resolution is so poor so hard to say… now waiting for Kilauea

      • They are lucky having the Virunga Highlands over a 1500 m above sealevel, that means the weather is livable, you can see that in windy temperature charts, virunga is cool and pleasant, while Congo lowlands to the west are an sauna hot in noon:,-1.827,26.988,8

        Kilimanjaro and Mount Kenya are also isolated cool “islands” in a searing savannah sea of lowland heat and with higher and higher cO2 levelsI doubt that the lowlands will be habitable for much longer without controlling the emissions, the rainforests for example will develop a deadly humidity and temperature combination with higher temperatures. I do remeber some cretaceous models going for a 50 c humid equator as avarge temoerature

  32. In North America all volcanoes between Shishaldin and Popocatepetl are dormant now. Is there a reason why the volcanoes on this part of the Ring of Fires are more rarely active than f.e. in the Andes or Central America? The volcanoes in this “gap” appear to do big eruptions between big time periods, while towards the south and towards Kamtchatka the volcanoes are more frequently active, but on lower scale.

    • Subduction is lacking for much of that section. And the Cascades are very dry, they prefer doing rare shield eruptions to frequent stratovolcanism.

      • Is this linked to the strike-slip fault (San Andreas)? How typical are shield eruptions there? How do they look like compared to Hot Spot shield eruptions?

        • San Andreas is more to the south, I think, the Cascades are subduction, but an odd type. Be it the influence of Yellowstone or the proximity to the East Pacific Rise, maybe the subduction of old ridges, the volcanism of the Cascades is very effusive and often happens from shields and cider cones. Eruptions would be similar to Paricutin volcano, but sometimes much bigger (they are called “Mexican shields” for something, most are in Mexico, but the Cascades also have a lot of them, like Belknap), and on rare occasions you may get a monogenetic version of Bagana.

          • Does this fit with the occasionally prehistorical Basaltic lava flows of Mount St. Helens? Historically the US west coast volcanoes only did explosive eruptions (Lassen and St. Helens) after long periods of dormancy, while the Central American volcanoes often do steady low scale activity (f.e. Costa Rica with Poas and Rincon). Are the historical explosive eruptions an exception to the rule of Cascade volcanism?

          • Lassen has some stratovolcano behavior, but overall it’s a complex of dacite domes (a bit caldera-like) surrounded by a vast field of cinder cones and shields, which erupt rarely but voluminously. St. Helens is more of a traditional stratovolcano.

    • There was something recently about St Helens being actively recharging, though not intruding towards the surface. But it is likely to do something again within 20 years, 1980 was not its biggest but it was a big eruption, most eruptions there are smaller. Its unclear if it would have blown up without the landslide decompressing, more likely a flank eruption, like the Goat Rocks eruption in the same area a century earlier. But it dud blow up and seems to have erupted out most of its conduit which quickly refilled and began effusive activity. I guess, 1980 was an unconventional version of a caldera, if a relatively small one for this sort of system.

      Next eruption might be the same as in the 2000s, more dome building. Although if it is a deeper magma recharge it could be more andesitic, so less dome building and more blocky flows. But really with a relatively young volcano like this its not really completely predictable. It might do a VEI 4 in 10 years too, or not erupt until 2100.

      • Prehistorically St. Helens often changed magma type. Once before 1980 there was an Andesite Dome eruption that produced the plug which suppressed the conventional Plinian eruption 1980 and led to a Pelean-Plinian event. Should we expect a return of Andesite again?

  33. Are all the big quakes in central Iceland real? If they are it looks like something majorly broke.

    • There seems to be some strong quake activity out on the Kolbinsey Ridge, close to Jan Mayen. Probably generates false detections, aka ghost quakes.

      Only one quake is still on the IMO map (not sure if more were showing before), and it has a listed quality of 36. I don’t think I have ever seen anything listed below 90 become verified as a real quake. Also, there’s nothing on the drumplots. This kind of activity would be visible in drumplots all over Iceland.

  34. Predominantly effusive Surtseyan eruption on Home Reef (Tonga):
    Is this system different to Hunga Tonga? According to GVP Home Reef is a Dacite volcano. 1984 there was a VEI3 with 12km high ash plume. Dacite is one of the most explosive magma types (Pinatubo). Hunga Tonga has Andesite to Basaltic Andesite. It is classified as Caldera volcano, while Home Reef is labeled a Composite volcano.

  35. Its hard to tell on this scale but on the 1 week plot the variability during the recent extreme tilt seems to be consistent daily, so might be a calibration error over what is really a mostly smooth line. There was a DI event just now but it seems to be over and still racing up. UWEV and CRIM have moved apart by 15 cm in a little over 3 weeks, and CRIM has also uplifted by 20 cm in the same time, as have OUTL, CNPK and AHUP on the upper SWRZ.

    CNPK and AHUP have actually reached their pre-2018 elevation, and are outside the caldera faults of 2018 so are not also offset by physical collapse like CRIM is. So it seems like Kilauea has now completely recovered the low pressure from 2018 and now only has to fill in the physical collapse pit, which basically means there isnt much extra space underground at the summit anymore… At least until there is enough pressure to reopen the ERZ.

    • I also noticed on this map that the Pahala quakes do seem to have a hard limit, they only occur west of a line that is also a shallow fault on Kilaueas flank where the Hilina Pali fault blocks stop. That fault isnt moving now or on the 3rd but did back in January.
      So the Pahala swarm seems to be a part of the south flank movement of Kilauea and Mauna Loa. Maybe it stops at Kilauea because its deep rift begins, and said deep rift is indeed very deep. The surface eruptions on the rift zones are controlled by summit pressure but it wouldnt surprise me if a percentage of rift magma is ultimately derived directly from depth. Or maybe more interestingly if Kilauea does rarely do eccentric eruptions that erupt out of the deep plumbing directly and dont involve the summit at all. Such eruptions are known from Piton de la Fournaise and are pretty rare, big ones being typically millennia apart, a timescale in which Kilauea will resurface itself multiple times over so the evidence is going to be pretty scarce. Its also the style of volcanism of post-shield Hawaiian volcanoes, which lack the shallow magma chamber but keep the deeper plumbing.

      The 1 month quake plot also highlights the mobile zo e of the ERZ. Goes down to inland of Kalapana, about to JOKA station and Heiheiahulu shield, where there was uplift from 2018-2020 and the 2018 intrusion started. So when the summit fills too far it might rush down there.

      • Kilauea is an absolute monster volcano, by just looking at the little scale bar there ( which St helens can be crammed inside ) kind of gives a sense of total awe just how massive its volcanic massif is and its only a map of the summit region and land based ERZ region .. goes a further 80 kilometers into the puna ridge…

        The pahala stuff also shows up nicely

      • As you mention the blue, deep earthquakes, there have appeared some blue deep quakes below the upper east rift zone. Sometimes Kilauea does an independent mantle-to-surface eruption that doesn’t rely on the Pahala system. Kilauea Iki was, if I remember correctly, one example for this, independent from the traditional magmatic system of Kilauea. Was Mauna Ulu preceded by deep earthquakes below the upper ERZ like this? If so, the present blue quakes could indicate a potential risk/chance for a future Mauna Ulu eruption.

        • No Kilauea Iki still went the ‘normal’ way but at the time the magma system was more of an intrusion complex than a homogeneous chamber. That, and the fact that I only recently learned that the 1959 magma intrusion was huge and only a little bit erupted at Kilauea Iki, most of it went into the ERZ. 1960 was as far from the summit as you can get on land and still erupted the same nearly ultramafic very hot lava, at least after a few weeks. So there was enough magma intruded to basically fill the entire plumbing system of Kilauea that existed in the 50s in one go. The erupted volume was 20 million in Kilauea Iki and over 250 million m3 at Kapoho, so likely somewhere close to 300 all up, maybe over double that which stayed in the ERZ depths. And it technically never stopped becahse Kilauea has been hyperactive ever since and only gotten stronger over time. The year average supply now might be more than the whole total in 1959…

          As for Mauna Ulu, it was normal. After 1960 the ERZ connector seems to have been wide open allowing eruptions and rifting basically all the way along it from Hi’iaka to Napau. Mauna Ulu formed basically where it bends the most. Same as above the magma system was very active but not homogenized so the magma is more primitive than modern stuff but nothing unusual. The magma chamber really didnt form until around 2011, when MgO values in the magma began to decrease and become consistent, as well as degassing being dominated by the now much higher and larger summit lava lake instead of Pu’u O’o.

          So basically 1959 was a big flood of very primitive magma from deep down that mostly went the normal way, Mauna Ulu had no direct deep source other than from the summit. At least, it had no separate feeder. Same for Pu’u O’o, ehich can be kind if thought of as Mauna Ulu reborn lower down. Same will also apply to a future shield east of Pu’u O’o.

          A true eccentruc eruption would probably be pretty distinctive. Probably very tall fountains and larger cones, but more importantly the magma probably having very high olivine content. There are some such cones north of Kilauea, they are 99% probably distal Mauna Loa ERZ vents but to my knknledge they arent all sampled so maybe one might be an eccentric Kilauea vent if not that, then maybe they are so rare they are long buried.

          • Where was the origin for the Kilauea Iki intrusion? The relatively primitive, ultramafic magma must have taken a different path then the conventional Kilauea Caldera magma. All intrusions have a source. Are there many or is there a deep monopoly ressource?

          • A paper I read said that the eastern part of the 1954 eruption–that on the caldera floor–was the same magma as 1959. I couldn’t wrap my head around that and I still can’t.
            Researchers of that era classified batches of magma based on when they first erupted at the summit. This meant that the 1962 ERZ lavas were termed ‘1967’ lava. That attempt at a coherent nomenclature faded away, thankfully.

          • I remember reading that until relatively close to the 1959 eruption the quakes were still under Halemaumau. There is a paper on Kilaueas historical changes that said the magma probably originated north of Kilauea but it went up under the central volcano. I think the paper is the same one that mentioned the common magma in 1954 and 1959.

            1959 had a lot of different magmas early on I think, its actually possible the original fissure was coming from Halemaumau but the eruption was definately more independent as it began becoming more paroxysmal.

            It really all comes down to the situation where Kilauea had no homogeneous magma chamber but a high supply. Up until the 2010s.

    • The daily variations have gotten to an amplitude of 6 microradians. I had never seen anything remotely close to this; I don’t think there have even been 1 micro-rad daily fluctuations in the past. I guess it’s summer’s solstice, but still, a month ago they weren’t even perceptible. UWE is in a vault underground, and I don’t remember seeing anything like this in other summers. Combined with the record-fast climb, the tilt just looks unreal right now. The deflation on June 23 may have been a pulse of magma moving into the ERZ, since it matched with a pulse of earthquakes along the Chain of Craters.

      It’s strangely quiet right now. Inflation is taking place at incredible rates. The deformation has far exceeded the previous high stand, yet the connectors and summit are very quiet, seismically speaking. The south caldera area is going to recover from 2018 deflation in the blink of an eye with the ongoing pulse.

      • Yes that was my thought too, the scale is huge, i guess it is a bit of a coincidence it is a daily fluctuation.

        There is a 3rd option actually for what might happen. At the current rate of uplift CNPK and AHUP will reach their 2018 level in under two weeks (!) And OUTL will do it in maybe a month. CRIM still hasnt shot up but its not unlikely most of its drop is more permanent not elastic. It might though similarly shoot off when the other two get above their 2018 value. Im not sure about PUHI or DEVL yet. But either way to erupt lower down on either rift requires a lot of pressure, maybe it is just going for it already and immediately, like it did in 1975 but way faster

      • I have seem to notice a pattern with the DI cycles with this uplift episode. The earthquakes are usually lower in activity during the deflation part of it, but as soon as it even began inflating, the earthquakes would be more continuous. The connectors are not even silent. A day or two ago, during another episode, there was a swarm of earthquakes within a 48-hour period at the East Rift connector. It wasn’t the most active, but it did signal magma is trying to get through into the actual rift. There is some kind of blockage there and it us only a matter of time before something breaks…

        P.S. this might break the 70 microrads recorded by UWE before the 1959 eruption of Kīlauea Iki, as you suggested…

        • I wil try to put together some visuals of my ideas later.

          I think the DI cycles are complicated, they are related to pressure more than supply rate because they dont really deviate from the long term trend and can happen pretty randomly. Te Idea HVO has is that it is similar to gas pistoning, only with density instead, with magma that is either slightly cooler or degassed sinking like a lava lamp and maybe at times overpowering the inflow. It also could be crystals of oliving settling out all at once as they become too big to be suspended, or accumulated crystals flowing down the conduit,the post 2011 lava is a lot less magnesian than before relatively so a lot of olivine has settled out, some probably being dredged up in the fissure 8 lava which was highly magnesian again.

          I think it was also Hectors idea that it could be the magma chamber growing too, with little intrusions and the walls between them caving into the magma. It is realistically probably all of these things and more…

          As I post this the tilt has just reached the 70 microrad mark since the last eruption. The inflation at SDH is also up around 90 microrad…

          • Yes, UWE has beaten its 1959 record. It’s very likely that this is the fastest supply-related inflationary tilting ever recorded by the station since it became in operation in the mid-1950s.

          • Why hasn’t this extremely fast inflation not led to an eruption yet? Where is all the intruding magma going to?

          • Its causing massive uplift of the caldera and the upper SWRZ. OUTL, AHUP, CNPK have all been uplifted about 20 cm in as many days. I think the seismicity on the ERZ connector might actually be induced by inflation of the south caldera instead of local magma pressure.

            The south caldera itself might be quiet because it has had two dikes intrude from it this year and the tension is mostly relieved. So an eruption might come about very suddenly

    • Can magma stored in crustal magma chambers below Reykjanes evolve into dacite and rhyolite? If that’s true, we can expect very explosive eruptions when basaltic magma from below comes into contact with a magma chamber containing dacite or rhyolite.

    • I just realized something insane. If the body feeding these eruptions is 50km^3 and it formed between 2002 and 2020, thats 2.7km^3 a year. Thats borderline insane and I have never seen anything like that.

    • Wasn’t there also a lot of inflation in the Krysuvik area before the concentration on Fagradalsfjall? Maybe we’ll see in future more of the connections between Fagradalsfjall and Krysuvik. Before the 2021 eruption, Fagradalsfjall was viewed as a subsystem of Krysuvik.

    • My guess would be it is actually an old body. Realistically hard to imagine something like that forming in 20 years wouldn’t be much more notable on the surface (just in terms of inflation!). So you have this big body, mostly solidified, so anomaly is not caught, then infusion of fresh material and heat, remobilizing some of that, raising the melt % to more noticeable amounts.

      Also note the numbers are probably high-balling. 10X5X4 in a cube is 200km^3. At 26% melt that is ~50km^3. If it is more spherical, volume is closer to 100km^3. And the language they use is *up to* 26% melt. So may well be closer to 20km^3 liquid volume. If you assume 10% eruptible, that is perhaps 2km^3 across two surface systems. Which is toward high end, but in ballpark of what the peninsula systems historically do.

      One significance though to me is that this means the systems of Reykjavik may well be real, separate systems, central volcanos at depth, if less apparent at surface if they have 100km^3 magma bodies. If we overextrapolate from this, maybe the whole peninsula is a system of magma chambers, each with two surface rifts, one each side, 5-10km apart. I do wonder if Eldvorp and Svartsengi are separate systems. Maybe something like this to overextrapolate? Which is another way of saying probably totally wrong other than 2.
      1. Reykjaves+Eldvorp
      2. Svartsengi+Fagradafjall
      3. Krysuvik might be one system. West side active, Kliefarvatn side rather inactive post-Ice Age.
      4. Brennisteinsfjoll: West side historically active, Hveradalir Geothermal Area eastern side.
      5. Hengill

      • The body was not there in 2002 when a similar experiment was done. They say, “The build-up of this reservoir was first noted with data from May 2020 (Hobé, 2022) but was not observed in the study by Tryggvason et al. (2002), which implies that the reservoir formed after 2002”. This is quite amazing.

  36. It seems hard to find current Iceland news in English on the web. I did find this today – which is a news release on whether or not to raise the defense walls for the power plant. I am going to assume that the decision has been made to increase the height of the protective berms, since yesterday feverious work is being done on the north berm.

    I have been trying to find a good live camera to watch the berm work, but the current crop of cameras seems to not have the right field of view on the new construction work. I did notice that new roads have been emplaced in the area near to the power plant, for the bulldozer scapers, the excavator (shovels) and dirt trucks to transport the scraped lava fill up to the end of the new berm reinforment terrace.

    • I think the one I posted a bit further up the comment thread is the best one:

      It’s at the top of Mt Thorbjörn and unfortunately Sylingarfell is obscuring the view of the far end of the berm that’s being worked on. Note that the road they are driving up on and its embankment IS the berm.

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