Since the eruption in Iceland started, some of us have been wondering about other past volcanic events that we could compare it to, in such a search I came up with an Icelandic eruption that I believe might by a good analogue, and no, it’s not the Krafla Fires.
Currently some of the characteristics of the ongoing eruption in Fagradalsfjall are that it is slow, both in intrusion and eruption, and that new vents keep popping up a considerable time after it started.
The Krafla Fires may seem like an adequate comparison to the Reykjanes Fires, and the current eruption of Fragradallsfjall, given that they all are episodic fissure eruptions, although even Laki was episodic, two-year-long and punctuated by short intense surges, there are thus many ways an eruption may be episodic. Rekyjanes and Krafla also have in common that their lavas are very fluid, some of the most fluid basalts in Iceland, they easily take on the smooth pahoehoe texture, even at high rates, and with very low explosivity, fountains not exceeding a height of 200 meters. But otherwise their similarities end there. Although it is not how the situation in Fragradallsfjall will turn out the Krafla Fires is one of the most fascinating volcanic events that I know of, so I will delve into them.
The Krafla Fires
Krafla is a basaltic caldera system, with just a bit of rhyolite. Although somewhat unappreciable in the landscape, its vast caldera collapse is 10 kilometres wide, up there with Grimsvotn, Bardarbunga, or Katla. The top of its magma storage lies only 2 kilometres from the surface, the magma was accidentally drilled into during a geothermal exploration in 2009, really shallow compared to Reykjanes where the magma comes from near the mantle-crust boundary 15-20 kilometres down!
Inside Krafla Caldera. Source Wikimedia.
The Krafla Fires opened in 1975 with a massive magma intrusion underground, a megadyke, that rifted a length of 70 kilometres. This triggered a rapid influx of magma into the shallow magma chamber under the caldera to restore the enormous amount it lost during the first intrusion. The caldera inflated rapidly until the rift snapped again, a dyke propagated into the fissure swarm, and then the caldera deflated sharply as magma drained into the growing fractures. This inflation followed by sharp deflation pattern repeated over and over again. A total of 18 dyke intrusions happened from 1975 to 1984, initially they stayed underground or had small eruptions that were almost accidental, where the dykes grazed the surface here and there. They filled the rift progressively so that the intrusions became shorter, closer to the caldera, a few of the last ones did have significant eruptions when the filling was mostly done,
This whole landscape is the Krafla volcanic system, normal faults and fractures visible in the image form when dykes intrude below the surface and open up the ground. Source USGS, by Michael Ryan.
Laki wasn’t so different, a series of dyke intrusions that breached the surface producing magma surges over a period of 2 years, 1783-85 , what sets them apart is that Grimsvötn had enough magma available to fill the rift multiple times over, so every dyke vastly overflowed, and the repressurization must have been much faster because the fissure swarm snapped again while the previous dykes were still erupting.
Eruptions of Krafla followed the typical sequence of fissure eruptions, they open with a curtain of fire, a flood of pahoehoe, then effusion rates drop exponentially, later it can focus into one vent and go on at a lower intensity for some time. One of its largest eruptions was in November 1981, the dyke travelled in one hour from the magma chamber to the surface, within another two hours a curtain of fire 8 kilometres long was already shooting from rows fountains and sending forth floods of fluid lavas. During the initial peak hours of the strongest eruptions in 1984 and 1981 effusion rates of 800 m3/s were probably reached, if not surpassed, and this was similar to the rate at which the previous intrusive dykes expanded.
Krafla erupting on September 5, 1984, the day after the onset, the eruption intensity had already waned considerably by this time. Source USGS, by Michael Ryan.
Krafla vs Reykjanes
I have been inspecting some of the old lava flows of the Reyjanes Peninsula in Google Earth, which I was talking about in my last article, it turns out there is some variety.
Hengill, Krýsuvík-Trölladyngja and Svartsengi erupt with great intensity, a curtain of fire feeds a flood of pahoehoe lavas of similar proportions to Krafla’s strongest, the eruption rate decays exponentially and may last for a total of a few weeks or so.
Brennisteinsfjöll is the exception, its eruptions are slow, long, complex, they don’t follow any general trend of decrease or increase in intensity. Fagradalsfjall, although shoulder to shoulder with volcanoes that are into lava floods, seems to have actually turned out the Brennisteinsfjöll way. In hindsight the rate at which the dyke grew, a mere 15-20 m3/s, a snail’s pace in the world of racing dykes, already pointed towards the eruption being a slow one. There is evidently a lot of magma in the mantle below Fagradalsfjall that is buoyant or pressurized and could readily erupt, 800 years of melting building up below the region, and if it could come out faster it would. If the dyke grew out so slowly it is probably because that is all that the conduit system that brings magma from the mantle into the dyke is capable of transporting. Presumably the space in the conduit somewhere down there is very little, so that the small opening and friction against the sides does not allow ascent to be any greater than that. As such, it is unlikely the eruption rates will exceed much more than 20 m3/s at any moment in the future.
The idea of a lava flood may sound attractive, however one should realize that this is something that happens very quickly, the peak eruption in a matter of a few hours, should it happen in the middle of a blizzard then perhaps the best part might go unseen entirely by everyone. Instead Fagradalsfjall seems to be putting a slow, long lasting, show that keeps changing.
I’ve got the impression from inspecting the lava flows of Brennisteinsfjöll that these probably formed in multistage eruptions where the active vent shifted location multiple times, that may have went on for multiple years and erupted more than 1 km3. Fagradallsfjall seems to be intent on shifting the eruption location, it has already opened three different fissures, this has surprised some scientists who, following the model where the dyke solidifies and output focusses into stable pipes, didn’t thought it should be possible for it to happen so far into an eruption. If we look into the recent past there are however a number of examples of eruptions that simply kept moving their vents around.
Surtsey
I think that the eruption of Surtsey might be a good analogue to the current eruption of Fagradalsfjall, as long as we ignore the difference that one was partly submarine whilst the other is subaerial. Fagradalsfjall is like a Surtsey out of the water. The eruption rates of Surtsey were low, around 5 m3/s when converted to lava, it lasted a total of 3.5 years, 1963-67.
Surtsey was a wandering eruption, from multiple vents along a 3 kilometre-long line. The eruption started from the vent Surtur I, which was joined 1.5 months later by Surtla that erupted for several days, Surtur I went on for about ~2.5 months. The activity moved to the vent Surtur II when Surtur I had waned, Surtur II erupted for about ~16 months. After Surtur II, a new vent, Syrtlingur, opened and erupted for ~5 months. After a brief break in activity, yet another vent, Jólnir, became active for ~10 months. Later effusion shifted to the first vent, Surtur I, for the 10 final months of the eruption.
Surtsey erupting in 1966 from the Surtur I vent. From USGS.
The way Surtsey kept shifting the action around defies the typical assumption that after initial fissure opening, the first hours or days, then the eruption settles into a single or a few nearby vents and stays there, this is because the rest of the dyke solidifies so output concentrates into small pipes, which is how it happens almost every time. However, there are several examples of eruptions that do not obey this law, during the eruption of 1730-36 eruption of Timanfaya, in Lanzarote Island, the focus of activity kept shifting, the last outbreaks were as strong as the first ones, the activity being overall rather slow. During the 1991-93 eruption near Nyamuragira Volcano, a new vent would open every 2 weeks on average, a few or one of them being active at any given time, they did not open through a single line but sporadically over an oval area.
Timanfaya, a spectacular volcanic landscape reshaped by the great eruption of 1730-36. By Dario Garavini, from Wikimedia.
Why do new fissures keep opening up?
Fagradalsfjall has opened 6 fissures already, it does seem to be walking down the path of Surtsey, or Timanfaya, or Brennisteinsfjöll. I do think it is likely that new vents may keep opening until the eruption stops because it is how this kind of volcanic event seems to typically progress, a fissure eruption that does not have a proper curtain of fire, that does not have a exponential reduction in effusion rate.
How is it possible that new vents would open up even when the dyke should have solidified already? It doesn’t seem likely the magma would come for the initial intrusion which should be solid by now, and not able to flow any more. However there are pipes filled with hot new magma rising from depth into the vents. Geldingadalir, or Smeagol, or Bob, or was it the Twins? however it was called, this vent was fed with hot magma from depth, its magma pipe could have broken at some location down below and fed a lateral magma-filled fracture that opened fissures 2 and 3, a small dyke branch. This does seem like a plausible reason.
Fissure 2 of the current eruption. From Wikimedia, by Almannavarnadeild ríkislögreglustjóra.
Some ground cracks did form between fissure 1 and the site of the incipient fissure 2. Ground cracks are possibly the best way of tracking the way magma moves underground, because at this point intrusions are small they may not generate detectable earthquakes or ground deformation, but they will probably open cracks. It is difficult however to monitor the opening of tiny cracks on the ground.
Often we may underestimate the complexity of a situation, for example we know that the dyke feeding the current eruption extends down to a depth of 5 kilometres, and yet we also know that the magma comes directly from a depth greater than 15 kilometres, with no intermediate magma chambers, so what happens in the 5-15 km depth range? Certainly the magma must have found a way through, not a very effective connection given that the intrusion and the eruption receive magma att such slow rates, however the exact way it happened remains unclear. When did magma start to rise upward? In January 2020 there was an intrusion, a sill, below Mount Thorbjörn, this is quite close to Fagradalsfjall, was magma already rising from the mantle then? Perhaps the intrusion was already growing long before it is assumed and it continues to grow now, as shown by the new fissures that opened up recently, and will probably keep doing so. How does the intrusion look like? a system of interconnected sills, dykes, with molten pipes transporting magma towards the vents and growing dyke branches? I guess this is up to our imagination.
Conclusions
The eruption in Fagradalsfjall is the subaerial equivalent of a Surtsey-like eruption, it seems also similar to the historical eruptions of the Brennisteinsfjöll Fissure Swarm, which happened around the 11th century, they were of significant volume and long-lasting.
New fissures will probably open along the dyke axis that runs from the eruption site to Keilir, at some point, days, weeks, or months from now. A decrease in surface volcanic activity may indicate that magma is moving into fractures towards a new eruption location, same is true for the formation of ground cracks. Old vents can be abandoned if the flow is redirected towards a new fissure. The eruption will probably end up lasting multiple months or years because the transport of magma from source to surface is slow.
This eruption is turning out to be really interesting, can’t wait to see what volcanic surprises await us!
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First
Thank you for the article.
When I take a look at http://jardvis.hi.is/eldgos_i_geldingadolum to see the graphics about the effusion rate and the total volume of the lava flows, I see “Síðan finnst ekki”. Site not found.
The webcams of RUV (both “Live from the volcano in Geldingadalir, Iceland” and “Live from the volcano in Meradalir, Iceland”) are still black. Has RUV taken these cams offline, or is there a technical fault?
It’s a technical problem, they lost connection to the cameras. They say they will send someone to repair as soon as the weather allows.
Oh and they are going to use the opportunity and move one of the cameras in order to get a better view. They didn’t say which.
Try this: https://jardvis.hi.is/eldgos_i_fagradalsfjalli
Earthquake swarm now offshore at the tip of the peninsula. Now what? Fun times for volcanophiles.
my bet is that is the spot of lava intrusin onto the dyke, could be enlarging or suddenly collpasing some sort of and this give the seismicity action. but in my opinion further, some hours we have to cinsider, then will be some eq at the other end, keillir area and them kabum to geldingadalir. uhoa..of the worst of nature fog is the real calamity
According to the weather reports it should clear up in an hour, so maybe the MBL cam wil show us something .
Also looking around google maps i came across aksja, looks like a interesting story there for that big eruption and lake.
Askja is a beautiful hike, made me think of Mars, except the warm bath in the Viti crater – and I am happy to have been there when an icelandic bathing outfit consisted of a rain cover and hiking boots and NOTHING ELSE. Afterwards the bus smelled of rotten eggs for the rest of the day.
Fascinating stuff well explained, thank you. Landscape architect earth at work.
Thank you Héctor! That’s a lot of food for thought. It really is going to be interesting to see how this eruption progresses….weather permitting!
now if Hengill came to life, with all that water in the system, that would be a sight!
I would think of the poor horses at Eldhester riding centre though.
Jesper has been found alive at well at around 6 o’clock.
I have told him that you are worried about him and that you thought he was missing.
I suspect he will swing by in the not to distant future.
Good! I’ve missed his enthusiasm.
”Cough cough!! Gollum!! cough
Im back …
But looks like the eruption webcams are not working well.
Most eruption webcameras are not working at all now… they are not sending live…
Anyone fix a live link to working eruption webcamera?
*crawling after working fagradalsfjall webcams*
Everyone is back! Can we now turn the eruption back on?
I am suspicious after this picture turned up, seems like Boritzky may have stolen the eruption…
More to come I am sure.
You think they are loading the cones to transport to Etna?
Loading the special tyre burners purchased from Elon Musk…eh?
Thanks a lot for the article. We’ll see what happens…. 😄
Have the lava samples from todays eruption been compared with the lava from the 11th century Brennisteinfjöll fissure system? Are they corresponding?
Thanks. I think it was mentioned in some reports that the current eruption magma composition is different to all other historic eruptions in Reykjanes.
Been having all kind of odd dreams about the current Iceland Fagradalsfjall eruption!
Last night in very deep sleep I dreamed that I and .. Qui Gon Jinn as well as my own brother went to Geldingadalir lava flows .. there we finaly removed and destroyed the caracther Jar Jar Binks.. by pushing Jar Jar into the molten lava river.
My brother gave Jar Jar Binks a ”police grip” then Qui Gon.. disabeld his feet with a nice lightsaber move. Then we walked to the ”Bob” vent and threw Jar Jar Binks into the molten rock, he yelled annoyingly and then silent… with only ”ballarbunga” or ”BoB” bubbling that was heard
😆
Episode 1 is a total mess with that goofy thing in it …. buuuut now back to reality
I wish they coud get the Iceland Webcams working now
Patience Padawan, allow the storm to pass and daylight to return before sending the techs to repair them. They are going to move one of the cams for a better viewing angle for your personal pleasure as well
Ah – you have returned! I was a little concerned over your silence. Glad you are back with us.
It was an odd dream indeed
Pushing Jar Jar Binks into the BoB vents lava flow .. these loong flappy gungan ears burned off instantly .. the result was something that looked like poor really burned toad.. thats also been flattened by a car 😛
Jar Jar binks is one of the most disliked film caracthers in history
Héctor Sacristán “This eruption is turning out to be really interesting, can’t wait to see what volcanic surprises await us!”
We are living in interesting times.
Iceland fire and ice, welcome and entertaining food for thought.
I love seeing people enjoy these eruptions up close, there is something so nice about seeing this.
If I lived on that island I would move heaven and earth to be near the eruption whenever possible.
The Island I live on is only 380 km² Iceland is 103,000 km², much admiration for their dedication to see this, it looks like a grand social occasion sometimes LOL. The weather is just as dangerous as the volcanic stuff!
Vikings obviously watched volcanoes on the very same peninsular in the past…
I’m glad too that this eruption is creating so much joy, other eruptions are not as pleasant and bring suffering instead… But it looks like this eruption is friendly and the lava flows not bothering anyone’s house.
And now a quake swarm starting on E side of fissure in Eiturhóll…
Would that be in the Hengill system?
Some information on Hengill:
The Hengill volcanic system has been quiet since a rifting episode in 1789 CE. Seismic activity during the last 10 years appears caused by geothermal exploitation (present power production: 420 MWe + 433 MWt) from the geothermal reservoir. Reinjection of effluent water has induced small but numerous earthquakes.
Monitoring involves seismic and ground movement surveillance as well as changes in fumarole and hot spring activity. An increase in fumarole activity, as yet minor, may be expected as a corollary of drawdown of ground water level due to exploitation.
Ground subsidence, as yet minor, accompanies subtraction of fluid from the reservoir. Only seismic activity, mainly due to water re-injection, has increased. This exploitation-related activity could obscure precursory symptoms of a pending volcanic and/or volcano-tectonic activity.
http://icelandicvolcanos.is/?volcano=HEN#
My guess is, that they are going to move the Meradalir cam and plop it right in the mouth of the exit behind the twins. Obviously out of harms way.
Put it on a blimp and give continuous views from above! Seems the only way to really keep track
That wouldn’t work: the blimp would blow away!
I read somewhere Yesterday hat they post such an official announcement…to fix ang move the cam on friday
I did notice recently how the Husfellsbruni eruption you talked about last time does look quite like what I think will form now. Its sort of a shield but its more an a’a shield with only some pahoehoe, and with a few obvious lava ponds. There also looks to be two major cones that are not really alligned on the fissure swarm, maybe fed out of a sill at depth. It does seem that the eruption now might be relatively localised to the area on Fagradalsfjall with the dike going to Keilir possibly being too old to act as a pathway now, but if Hussfellsbruni was about 1 km3 and possibly just a stage of an even bigger eruption overall then Fagradalsfjall is going to need a new name when this is done. Pu’u O’o is 150 meters tall and most of its lava flowed far away from the vent, an eruption that big where most of the lava stays within 5 km would create a genuine new mountain…
When doing research on my article I found a pdf that is of the entire history of the Lanzarote eruptions as observed, problem is it cost over 100 pounds to get access… I presume that means it is quite the real deal though.
We may be able to access it for you, if you let us know which publication it is and if it is covered by agreements. Or you could ask you local library whether they can get hold of it.
https://link.springer.com/chapter/10.1007/978-94-017-8628-7_23
Was euros not pounds but same difference.
Found it and have asked for it to be send to you
I do know this link in Spanish that also comes with a map, that can be interpreted whether you know Spanish or not, with the distribution of flows and a timeline of the phases:
https://digital.csic.es/handle/10261/3309
There are very few descriptions of the eruption, for some reason only the start and the end was properly recorded, so much of its sequence is not well known.
You can guess a lot of things using Google Earth though. For example, there are a lot of narrow flows which overlap on each other which shows the eruption was long (obviously), but also that it stayed at low eruption rates, because there are no extensive sheet flows. On the other hand it was strongly explosive, made a lot of sizable craters, the cones are very big which show they were exploding for long periods, probably strombolian-like activity. Magma seems to have been somewhat viscous, and maybe gas-rich too.
From what I could read the first eruption was fast and very fluid, the craters are still big but the lava is an ultrabasic nephelenite similar to Nyiragongo and the lava flows are not viscous looking at all. Later eruptions occurred along the obvious fissure starting in the ocean and goign east, these were characterised by constant eruption rates of about 20-30 m3/s as you say and with lava slowly evolving from nephelinite to tholeiite basalt, each time the vents shifted this same sequence took place. It does look like the lava might have been similar to Etna basalt towards later parts of the eruption though, or there was water interaction, but in general the lava was pretty liquid as it forms spatter cones and lava ponds all over the place.
It looks like there also were lava lakes that were created in the bigger cones too, probably not convecting but similar to the pond of lava in the Gollum vent, or the ones in Marum before 2018.
I guess everyone left the island after the first year, probably a good idea.
We received the following comment from a commenter
Dear Volcano Cracks!
with high interest i am following your posts, learning a lot, smiling at style etc.
I would to like to add an information to the Hell Machine: When visiting Lanzarote, i read a lot about its history.
During the eruption beginning 1730 described by Chad, he wrote, “not many people stayed beyond that stage of eruption”. They died. The Spanish king forbade them to leave the island. (The richer among them might have reached other islands, or the African coast.) Those who stayed were condemned to death. Not all kings are kind . . .
Thank you for sharing your profound geological knowledge with us!
I don’t know. I checked several sources. No death toll ever on record. Father Andrés Lorenzo Curbelo from Yaiza decribed dead fish. So, this kind of information would need a source.
Looks like the mbl cam wants to clear up a bit now
Just as foggy …. OTH it is brighter than you might expect.
Odd shaped cloud on the Kverkfjöll webcam; hope it is not prophetic 🙂
https://imgur.com/QMVZmy4
Source for image: https://www.livefromiceland.is/webcams/bardarbunga-2/
Has anyone noticed that the IMO has been relocating quakes lately (the ones in red dots indicating recent). Just now I see a cluster located near the big lake in Iceland, but the cluster disappeared just off the tip of the peninsula. I checked 3 or 4 times and each time I checked the recent quakes are being relocated on the map.
I think the cluster off the end of the peninsula is stil there, it is just over 4 hours old now. The cluster to the southwest of Thingvellivatn is a new cluster. It seems to far west for the Hengill system though and too far north for Brennisteinsfjoll. It basically seems to be in nomansland.
22:26:15 shows no activity at all at the Geldingadalir fissure system. See https://k100streymi.mbl.is/p2p/webcam1
ahaa.. as i said..after south tip of peninsula swarm will have in north at the other end of a dyke some eqs..which just start to pop up in about 3 hours…then let’s see our fissure activity….will increase. one strange observation I don’t know where and what is Eiturhóll where the eq are at 0.1 km deep….could we consider it next vent location candidate??
The quakes at Eiturhóll are man made. They are injecting water into drillholes that are located there.
I was wondering whether there was geothermal activity going on there.
so suddenly? if you look at all seismic activity sin january seems the northen dyke head….
Injection hole located at 64°N 21°W
https://orkustofnun.is/borholuleit/nr/96536/?iframed
There are so many drill holes over there, I just automatically ignore quakes there at this point. Kinda like the story about the boy who cried wolf. We all know how that story ends 😄
Here’s a useful resource: a map showing every borehole in Iceland, including depth, date drilled, and a bunch of other technical data. Cold water wells, gradient wells, and of course hot water and steam production wells are all plotted. You can locate other energy resources, too: map.is/os
timelapse montage from yesterday: https://youtu.be/oTlIBt2Y-hU
https://www.mbl.is/frettir/innlent/2021/04/15/oroi_aukist_en_adstaedur_oljosar/
Giggle translate with edits by myself (yes I’m that lazy)
*The article used the word “óróamælar” or “tremor sensors” rather than the usual “[jarð]skjálftamælar” or “[earth] quake sensors”. Reasonably sure i translated that right
Also those are some wine
all tremor graphs from metoffice iceland/eartquakes go wild today….unfortunatelly i dont understand the meaning of them but they are quaite akward…
I’m going nuts not being able to see anything..
Can’t say i miss those crazy storms lol, though the weather over here can be a bit boring outside of tornado or ice storm seasons
I know the feeling. Lived in Norway for a couple of years. A little strange getting used to constant never changing wheather and never any wind instead of 4 seasons per day 😃
I remember being on the Lofoten Islands in 110 mph winds. It felt like the fisherman’s cabin I was in was either going to take off or be inundated by the storm surge. A 55 seater coach was blown off the road, yet somehow the driver managed to keep it upright and there was only one person with broken bones.
For those not so familiar with wind speeds in m/s, 41 is about 150 km/h or 90 mph.
strange behaviour…each and everyone of mila cams show a black night with more or less human lights…but mbl cam shows a big level of surrounding light. white. no orange or so….if we remember the fox pictures…
yeea…fog start to fly away….some volcanic lV spots starts to apear…and i suppose that they put a black/white filter to cam…
Glimpses of Vent 2 can be seen on mbl cam. Looks like it’s quite active.
yes, vent 2 is a surpraie…sent irdiscent lava down valey, otherwise they are all live and shiny. I thought for a sec that all this chill will freee them…let’s chase for changes…
Finally..we have view
All vents could be seen around 23:57. Looks like vent 3 is fountaining quite nicely. Vents 5&6(the new twins) are also very active.
i see fire ….I see fire burn on and on the mountain side…
Just a random question… how is the VEI calculated for a small scale fissure eruption like Fagradalsfjall? Quite different from a stratovolcano putting up sheds loads of ash…
VEI-0 due to plume height <100.
It cant, VEI is for tephra, hence the E stands for ‘explosivity’. It also seems unimportant how long it actually takes for the eruption to happen too, a VEI 4 can be a small eruption that lasts a month like Eyjafjallajokull in 2010, 0.12 km3 of tephra in a month, or a big eruption that doesnt last long enough to get a bigger number, like Kelud in 2014. That eruption was 0.8 km3 of tephra in only a few hours, the most intense eruption of the 21st century so far. Both though are still VEI 4. The Hatepe eruption of Taupo was also a VEI 6 and was smaller than Tambora by quite a lot, but its ignimbrite sheet was just as extensive as the one it created in the VEI 8 Oruanui eruption, it was clearly quite a monster and probably callign it a VEI 6 isnt really giving the true scale of the eruption.
What can be compared between the two is eruption rate and intensity. Some effusive eruptions are extremely intense and have eruption rates that are just as high as a plinian eruption, probably the best example is Mauna Loa in 1950 which had effusion rates equivalent to a VEI 5, a 20 km long fissure erupting lava fountains 50-100 meters high and lava flowing at a speed that is faster than you can run. A few years of eruption at Pu’u O’o would give you the volume, but its incomparable in the intensity.
In this case though Fagradalsfjall is still maybe a VEI 1 equivalent, its very small just seems also to be very persistent.
It really isn’t. The ‘E’ stands for explosive and this eruption isn’t. The lava output should not count. Of course we have a lot of discussion on this!
Probably a poor analogy, but reminds me of diagrams of mid-Atlantic rift, where the sections between each transform fault ‘do their own thing, each in their own time’, with strain re-distributing itself hither & yon, with ‘black smokers’ flagging recent activity along linear grouping…
For something like North Anatolian fault, the ‘strain field’ is well monitored via GPS. And, yes, ‘The Big One’ does seem to be stalking Istanbul, unless the ‘mostly stuck’ on that section is relieved by transition to ‘mostly creep’…
Have we a strain-field model for current Icelandic activity ?
And, are the intrusion dikes ‘push-apart’ or ‘pull-apart’ ??
Serious swarms with many green stars along MAR north of Kolbeinsey. Not uncommon with green stars here but less common with so many. Spreading event? At previour occations it has propagated south towards Tjörnes fracture zone. https://en.vedur.is/earthquakes-and-volcanism/earthquakes/atlantic/
Informative article about La Soufrière’s ash and sulphate plumes from the NASA Earth Observatory guys:
https://earthobservatory.nasa.gov/images/148190/tracking-la-soufrieres-plume
So what is the latest on the cameras?
Forgive me for amateurish questions. But am I wrong to se this as an event driven by mainly tectonics? Magma rather getting pulled into places that want to give than forcing its way?
Is it wrong to think the strangeness of the dyke formation comes from the stress and weak points already there?
Started by tectonics, but driven now by magma pressure. It is a combination of both, the magma wont erupt if it was entirely passive but the magma also hasnt got enough power to push the plates.
This eruption though is unusual, it is probably also the result of a lot of magma accumulating in this area which hasnt erupted for a very long time. As Hector says Krysuvik and Svartsengi both have very intense eruptions, and this eruption is in between them so the fact it isnt intense is maybe something to think about for future scenarios. The magma conduit isnt as big as it could be evidently, so it will stay slow if there are no changes but will also last a long time. Thing is if we combine this with my scenario then the conduit will melt open wider, which will increase eruption rate. Its not impossible that a curtain of fire or a high fountain will erupt from Fagradalsfjall at some point, if the narrow conduit gets larger and allows the magma to escape.
Also important and forever an unknown is how much magma has accumulated here. It could be 800 years worth which might be , but it also could be 10,000 years worth and I dont think that much magma can erupt just at the rate it is going now, something is going to give eventually. I expect a change of that magnitude will be obvious but also could be quite sudden, or it might be a gradual ramping up to a high rate.
There’s steam coming from the ground in front of two of the central vents on the mbl cam. (When the vog/fog clears). I’ve lost track of the numbering system… pretty much in the centre of the screen. New vent on the way?
Eruption does look subdued compared to the other day, I expect a new vent is on the way somewhere yes, magma filling in every last little space underground. Somewhere above there was mention of tremors that look a lot like when new fissures open being recorded during the storm. Maybe a fissure opened south of crater 1.
I updated this yesterday, if it helps with the numbering (ignore the turquoise placemarkers, I couldn’t remove what was already on Earth). The positions of the fissures and vents are now more accurate than they were.
Also, the map at the bottom of this page might help, although it isn’t as obvious in terms of the numbering sequence, without having to click.
https://maps.acme.to/gos/
Thank you!
On the mbl cam’s chat, someone suggested that the rocks and gravel visible between the camera and the impenetrable wall of fog might be “rhyolite and compacted tuff”. But Reykjanes doesn’t do magma chambers, so wouldn’t finding rhyolite there be about as likely as getting some sort of fancy high-test racecar fuel directly out of a Texas oilwell without a stayover in some refinery’s fractionating column first? Or did there used to be central volcanoes with magma chambers in the vicinity of Fagradalsfjall in the geologic past, even if that type of volcanism no longer happens there now?
weather cleared up 🙂
All the cones except for #4 seem to be active, especially the newest one. Will be very interesting when the ruv webcams are back online.
I have noticed that this month there have actually been quite a lot of deep earthquakes at Kilauea, not in the Pahala swarm but actually just east of the caldera and going somewhat north. Looks a lot like the pattern of quakes seen there in 1959 but a bit further south and not quite so deep. One of them was a 3.3 about a month ago, quite big for that depth.
Looks like Kilauea might get a bit more interesting later this year.
Can’t find any cam site on my tiny pad. My computer is kaput. Any live feeds available?
https://maps.acme.to/gos/ the second raw both of them thermal and the samsung
Try to link reply for you. But end up on normal postings. 🙂 So its under this.
https://m.youtube.com/watch?v=I1I-0PUhFmU think only this.
so any local news?? does the yong twins managed to break free lava toward meradalir thru back of old twins? I see they build a high level lava pond..but i do understand the lack of info, iven fox do not get them nose out in this hush weather
Have looked little but cant see any new reports. Its early still and like you say weather. 40sec/m wind even the most hardcore entusiastic stay inside i think 🙂 but think it comes soon. And always when i post it show up something just 😉
AVO Semisopochnoi RED/WARNING – Sustained ash eruption with plume extending SE more than 350 km and 20,000 ft asl
https://twitter.com/USGSVolcanoes/status/1382896411440664584
So far one one….the young valley twins mirrored the old one. One high vent and a low one with a bigger opening.,…compulsive nature behaviour
At last something happening. Three vehicles have arrived on the MBL camera; hopefully camera technicians.
Two of the S&R vehicles leaving again. Perhaps preparing for renewed crowds of onlookers?
As I suspected this article is not quite on top of the facts as related to plume/SO2 height/volume observations of La Soufriere. Top column (as per NASA) is at ~20 km. Upper atmosphere ash/sulpuric oxide injections stands at 0,4-06 Tg (as per NASA).
Article: https://earthobservatory.nasa.gov/images/148190/tracking-la-soufrieres-plume
Excerpt: “Volcanic plumes that reach and linger in the stratosphere can start to exert a cooling influence on global temperatures. “The current thinking is that a volcano needs to inject at least 5 teragrams of sulfur dioxide into the stratosphere to have measurable climate impacts,” explained Michigan Tech volcanologist Simon Carn.
After about a week of explosive eruptions, satellite measurements show La Soufriere has delivered about 0.4 – 0.6 teragrams of sulfur dioxide to the upper atmosphere. That is already more than any other Caribbean volcano has produced during the satellite era. Those numbers could increase if the eruption continues. “Moderate eruptions are also far more numerous than the really huge ones, so the cumulative effects of such eruptions can be significant over time,” added NASA climatologist Ralph Kahn.”
It would seem the eruption is apx 1/10 into a (small) climatic incident. And it seems a new explosive episode is on its way. Hopefully just a small one.
https://volcano.ssec.wisc.edu/imagery/view/#sector:West_Indies_2_km::instr:ABI::instr:ABI–MESOSCALE2::sat:GOES-16::image_type:Ash_Height::endtime:latest::daterange:60
Raman Lidar spectrography gives us so much accurate data than the old IR did. Also related to measuring the width of the effective band. It also gives us quite different pressure/temperature data of the atomspheric gases in the rising atmospheric column and their single and internal effects. 😉 It is like the difference between a cheap mono radio and and an expensive Dolby Atmos set up.
My excuses to Hector; the previous article. Good read Hector. The high lava temperature makes this one a joker/wild card as compared to Surtsey in my view. And I have not found any seismic data up to the Surtsey eruption to know if it was similar in having a large tectonic episode pre the eruption.
An interresting read on tectonic episodes. Pointing towards….? 😉
https://astronomy.com/news/2020/07/powerful-eruptions-on-the-sun-might-trigger-earthquakes
I think the whole field of cosmology (which also will affect how we view volcanism/tectonics) is entering a paradign shift where man’s static theory-thinking stands in the way of the speed of it more than findings and observations does. Thomas Kuhn had a lot to say about the mechanisms involved.
And many excellent minds formulate the reasoning behind why these scientific leaps/revolutions – based on observations – do not happen over night.
Back to Hector; heat might be the key to understanding how this will evolve. Or not. But from my long experience heat is the key to either clogging or opening tubed systems during combustion. Where both pressure and temperature is the keys to either clogging up og keeping the system free flowing. Small scale and obviously not fully compareably, but still.
During the first venting episode of Bob/Twins/take-your-pick several commenters saw the same; the ridge to the left of the eruption was – and most remained – snowfree. First i thought it was wind-related but then temp fell to -10 C and it persisted. We now know this area is where most new openings are situated. Wo. observed high EQ activity preceding the opening. It is like melting chocolate… And that analogy could be important for the general feed from below. Depending on pressure. Because we know the T is sufficient.
The first visitors are arriving on the MBL camera.
I had a look in on the working cams just now. Has Iceland switched off the eruption? It seems very quiet in coneland.
Vent number 5 (?) nearest the original cone seems very active from the MBL camera.
Might be a bit less active but I think most of it is because the other cones are open in the other direction, so only spatter that goes higher than the cone is visible. There was tremor of a new vent opening recently so there could be a more active fissure to the left and off the screen, or possibly magma moved into a new area and vents might start opening outside the area of activity so far. We will know soon I expect.
25% of Icelandic adults have been to the eruption site 🤓
I have a link to the MBL camera (on which a lone bloke appears examining rocks and ignoring the eruptive drama). Are there any other cameras back up yet, please?
He seems to have fallen over.
Oh. Back up and going around in circles. Perhaps a geologist.
I think he is one of a party of 4 that arrived 2 hours ago, The other 3 are watching the eruption just below the active vent. He wandered off by himself after half an hour.
Still bothering those rocks by the look of it.
Things seem quiet around 1:34pm but it makes me wonder if new vents to the north might be in the making?
Keep wondering same thing and scrutinising right side of mbl cam in hope of spotting something. Funny how addictive this is, but only because it is such a harmless eruption so far.
Actually, I’m wondering if a new fissure opened up on the left side, outside of the mbl cam’s field of view. There is so much smoke and fumes blowing over from that direction. Makes me think of another (new) vent on that side…