Jon Steingrimmson was deeply worried. The eruption had been going on for three weeks already. Lava coming down from the hills, flowing down the river valleys and covering the farm land. But it wasn’t the lava that was doing most of the damage (at least not yet – worse was to come). It was what was falling from above. It was making the land uninhabitable:
“More poison fell from the sky than words can describe: ash, volcanic hairs, rail full of sulphur and saltpetre, all of it mixed with sand. The snouts, nostrils and feet of livestock grazing or walking on the grass turned bright yellow and raw. All water went tepid and light blue in colour and rocks and gravel slides turned grey. All the earth’s plants burned, withered and turned grey, one after another, as the fire [lava] increased and neared the settlements. The first to wither were those plants which bore leaves, then the sedges were checked, and the horsetails were the last to go, and would later be the first to return. […] The foul smell of the air, bitter as seaweed and reeking of rot for days on end, was such that many people, especially those with chest ailments, could no more than half-fill their lungs of this air […] it was most astonishing that anyone should live another week.”
Jon (the local vicar) wrote this in late June, 1783, when the Laki eruption was in full swing. His report gives much of the eruption and its devastating impact on the local people. Over time the eruption would wax and wane, with new earthquakes heralding new outbreaks and new lava flows covering farm after farm. Jon Steingrimmson’s church was spared, just, but life in the region was on the edge for months. By November the eruption had diminished and no new lava would appear on the farm lands. But by this time much of the farmland had become unusable, turned into a sandy desert. There was no hay for the winter, and the sheep were too thin to produce any meat. Some cows and sheep just survived on the meagre rations. Further afield, farms had suffered less. Jon mentions that animals a bit further from the eruption did better, especially those grazing near the sea. On the islands off the south coast all farms animals had survived this phase. The vegetation was badly damaged over much of Iceland, though, and much of the trees, moss and plants would not recover for several years.
But now a new problem appeared. The livestock was not getting better, in spite of the slowing down of the eruption. In fact, quite the opposite. Jon describes the afflictions of the animals in great detail. He mentions the appearance of hard swellings on the joints and elsewhere on the body of the animals. The bones themselves were weakening, leaving the jaws so weak the animals could not eat. They had open wounds which would not heal. Most afflicted animals died. And people started to show similar afflictions. Eating barley brought the disease, but eating the rye seemed ok. (Barley was spring sown and would have growing during the eruption, while rye is sown in early autumn.) As autumn passed into winter, death and famine was spreading across Iceland.
Volcanic toxins
Laki was a particularly bad eruption. Whilst the lava covered valuable farm land and devastated loal communities, the ash and bad air affected all of Iceland. No one was safe. The human population of Iceland dropped from 48,884 people in 1783 to 38,363 by 1786, a reduction by 22%. This is not the number of people that died: many people may have left the country, and in fact Denmark (Iceland was Danish as the time) considered evacuating the entire population. But what made the eruption so deadly?
Traditionally, sulphur has been considered as the main culprit. Sulphur is indeed a toxic substance, and Jn’s description of the yellow feet and snouts of animals shows that the ground and vegetation were quickly polluted with it. The light-blue water he mentions was also was caused by sulphur, and later Jon describes that burning the peat and hay gave off blue flames. Many animals succumbed quickly, sometimes within days of the start of the eruption: the sulphur poisoning may have been involved. Later in the year, while Laki was winding down and sulphur emissions were much less, more and more animals died. Half of all cattle in Iceland, 80% of all sheep and 75% of the horses died. In numbers, the toll was 11,000 cattle, 200,000 sheep and 28,000 horses.
There were hardly words to describe how the sheep just withered away. No one had the foresight to see that it would have been for the best to slaughter them all while they still had flesh on their bones and could be rounded up, and thus have food. (Jon Steingrímsson)
Jon thought the affliction was scurvy, the devastating disease of sailors on long journey caused by the lack of fresh food (vitamin C, we now know). But it wasn’t that. It was fluorine poisoning, and it was happening not just where Jon lived, near Laki but throughout Iceland. The animals had succumbed to fluorosis.
Fluorine
Volcanoes emit some unpleasant stuff. We already mentioned their sulphur compounds, which can reach dangerous or even lethal levels near volcanoes. They would have rendered large areas around flood basalts eruptions unsurvivable, such as the Siberian traps, the Columbia basalt and, at the minor end of the scale, Laki. CO2 is less publicised but is equally dangerous when it collects in low-lying areas. (And no, volcanoes contribute far less CO2 to the atmosphere than we do, but close to volcanic areas they can be dangerous even when the volcano itself is not erupting.) Mercury is less advertised, but could be another major issue in the case of a flood basalt. And fluorine is the final nail in the coffin.
By the way, the chemical element is called fluorine (symbol F). Fluoride is the name for the negative ion, F–, or for any compound that contains fluorine. Toothpaste, as an example, contains such a compound. Fluorite is the name for the mineral CaF2; it is also called fluorspar.
Fluorine combines well with sodium or silicate. In magma, it can form CaF2, while on the tephra it mainly forms CaSiF4 and NaF. It dissolves easily in water as F–. The name ‘fluor’ means ‘flowing’ and it may relate to how soft fluorite (or fluorspar) is. The same mineral also gave rise to the term ‘fluorescent’: although it is transparent in itself, it can show a variety of soft colours. I live close to Castleton, a small town in the UK where a mineral called ‘bluejohn’ is mined. It is used to make ornaments with a mix of purple and yellow colours. The main mining cave there is well worth a visit. This particular mineral is found only in a few places around Castleton. It is a fluorite, and it was deposited some time ago (300 million years or thereabout) by crystallization from hot fluids, at that time a few kilometers below ground.
A bowl made from bluejohn. Source: wikipedia
Fluorine dissolves easily to form HF. This dissolved fluoride is ok for consumption, in small amounts. 1mg per litre is harmless and is even beneficial for teeth, which is why it is used in toothpaste (at this low concentration) and in mouthwash. This is also about the level in natural sea water (1.3 ppm, to be precise). But at much higher concentration it becomes a potent toxin.
Fluoride toothpaste, by the way, contains 1ppm, a safe level. The panic websites which warn against fluoride in tap water tend to overlook this small detail of concentration. Presumably they are also against oxygen. But dental products (mouthwash and toothpaste) containing fluoride are not for consumption. Drinking mouthwash regularly could cause mild fluoride poisoning. (Buy the way, rat poison can also be fluorine-based and can pollute the food chain if you let it. Don’t eat the rats your cat brings home.)
Plants are pretty poor in taking up fluorine from the soil, and concentrations per dry mass are typically no more than 2- 20 ppm. There are exceptions, one of which is tea! Oats are also reported to better than average in this. But air-borne fluorine, including when dissolved in rain, is taken up readily by the plant leaves. Overall, fluorine concentrations in soil are much less problematic than concentrations in air and water.
Fluoride poisoining
Fluoride poisoning affect several parts of the body. A little fluoride strengthen bones but at higher levels they become brittle while the bones thicken and bone growth may occur in unexpected places such as on the jaws of animals. Some of the symptoms become very similar to arthritis. At the highest levels the bones become very weak. Once the bones are saturated with fluorine, the excess enters the soft tissues and the animal quickly dies. Jon describes how soft the bones of sheep had become. The meat of the animals became almost inedible and people who did eat it (for lack of other food) developed the same symptoms. This became endemic during the winter, months after the tephra fall has ended.
Sheep metatarsal, following the 1845 eruption of Hekla.
Source Suttie 1964. https://doi.org/10.1080/00022470.1964.10468315, Walser III et al. 2020 https://doi.org/10.1007/s12520-020-01026-0
Many of the symptoms which Jon described (I won’t go into too much detail as we have some younger readers) are readily explained as the toxic effects of high concentrations of volcanic fluorine – fluoricide, by manner of speaking. In the early days of Laki, the tephra lying on the grass would have contaminated the animals directly. The fluorine dissolves into water, which is plentiful in Iceland, and animals would drink this water. Grass also takes up water and so collects fluorine long after the tephra has fallen to the ground: animals continued to be affected.
At levels of 250 ppm (or more) of dry mass of grass, animals that eat it die within days: the death of animals in the first days of Laki which Jon describes may have been due to fluorine poisoning rather than sulphur. But even at levels that are several times lower, animals develop fluorosis. That level was probably exceeded over much of Iceland in the months following the Laki eruption.
Laki fissures (white broken line) and lava flow (black) in relation to the active volcanic zones (dark grey) in Iceland. Abbreviations are: West (WVS), East (EVZ), and North (NVZ) Volcanic Zones. Also shown are 0.5 cm isopach of the Laki tephra fall as well as the estimated outer limit of the area affected by fine ash. Open circles show locations were fall of fine ash was reported. Large crosses indicate areas were livestock died in large numbers within 2–14 days of the onset of the Laki eruption. The grey shade shows where more than 60% of the grazing livestock died and crosses indicate locations or regions where reports on symptoms in livestock are consistent with fluoride poisoning. Source: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2001JD002042
In people, an intake of 10 grams of NaF (another common compound of fluorine) is lethal – this corresponds to about 50ppm of their own mass. People in Iceland were lucky that rye provided a food source that had been less affected, and of course the locals ate fish and seals as well. Otherwise, mortality among the people could have been as bad as that among their animals. I admire vegetarians – but sometimes they do take a risk.
Fluorine in food or drink is taken up by the body and enters the blood stream. Most is expelled by the kidneys, but some ends up in bones and teeth. Teeth of course grow only during youth, and later exposure has little effect. Bones, in contrast, take up fluorine throughout life. The fluorine tends to stay where it is put – over a life time, the fluorine fraction in teeth remains constant but in bone material it slowly increases. At bone levels of 4000 ppm or higher, some skeletal fluorosis may set in. Significant effects may occur at levels above 6000 ppm. That only happens with exceptional exposure to fluorine, though.
In Iceland, enhanced fluorine levels have been found in some medieval skeletons, but not with levels as high as this. None of the skeletons are from the Laki period itself, but some of these people may have been exposed to drinking water still affected by the Laki tephra, or in some cases from Veiðivötn (1477 AD). But this exposure was not at worrying levels.
Curiously, worse fluorine exposure has been found in skeletons from Herculaneum. Romans living below Vesuvius had been exposed to toxic levels of fluorine, presumably in the drinking water: fluorosis was endemic there. At this time, Vesuvius had been dormant for centuries. The pollution must have come from water interacting with old ejecta. Fluorine loves water.
Iceland’s volcanic fluorine
In Iceland, the main fluorine culprit is Hekla. It dusts a large area in tephra several times per century and its ejecta have a high proportion of fluorine. Several of its eruptions (1845, 1947, 1970) were followed by sheep fatalities from fluorosis.
Volcanic fluorosis of sheep is not unique to Iceland. It is also known from the 1988-1989 eruption of Lonquimay in southern Chile and from the October 1995 eruption of Ruapehu volcano in New Zealand. But it is much worse in Iceland. To quote Thordarson: “if fluorine were gold, Iceland would be a fabulously wealthy nation“.
Hekla’s eruptions are dwarved by Laki. It erupted 15 km3 of lava, as much as Hekla might do in a millennium or more. The local population, including Jon, were exposed to 1000 years of fluorine within a few months. Laki’s lava contained fluorine at a level of typically 600-700 ppm by mass (0.06%). This is only a few times less than the amount of sulphur.
The total amount of fluorine, for an eruption volume of 15 km3 of lava, is around 2.7 x1010 kg or 27 Mtons. In magma, fluorine is present in the form of HF. The spatter deposits left by Laki’s fountaining contained less fluorine than the magma, at roughly 400 ppm, indicating that about 30% of the fluorine (8 Mtons) had degassed from the magma. This is not surprising since at normal temperature and pressure, fluorine is a gas. (The boiling point of F2 is -140C, that of HF is 20C.) The degassing occurs in two places. The first is at the vent, and the second is at the erupted lava fields. The solidified lava has slightly lower fluorine content than the fountaining tephra deposits. Thordarsson finds that 27% of the fluorine was degassed at the vents, 5% in the running lava and 20% while the lava solidified. In total, half the erupted fluorine ended up in the atmosphere, amounting to some 14 Mtons of HF.
How bad the degassing was is shown by a simple comparison, given by Thordarsson. During peak Laki, June to end of July 1783, Laki put 1.7 Mtons of SO2 per day into the atmosphere. The long-lasting Pu’u’O’o eruption in Hawai’i, responsible for Hawai’i’s vog problem at the time, produced 0.7Mton per year. So Laki produced twice as much per day as Hawai’i did per year! And that is for SO2. Laki was higher than average in fluorine, so for that element the comparison will be even worse.
Fluorine vapour does not stay in the atmosphere. It is highly reactive. At temperatures below 600C, it quickly forms CaSiF4 and NaF. In the eruption column, the tephra provided the perfect conditions for these reactions and so the fluorine attached itself to the surface of the tephra. Counterintuitively, most of the fluoride is on the smallest grains, as there are many more of them and they have much more surface area per gram of tephra. Grains smaller than 1 mm accounted for less than 20% of the total mass of tephra, but they carried most of the fluorine. These small grains stay aloft longest and travel furthest. This is why fluorine poisoning affected all of Iceland, even in areas where only a very thin layer of tephra came down. (Pele’s hair has an even larger surface area for its mass, and would be expected to be coated with fluorine. But this stayed close to the eruption itself. Jon mentioned it as occurring there.)
The eruption column of the fire fountains of Laki reached heights of 10 km, pushing the sulphur up to the upper troposphere and lower stratosphere which allowed it to reach around the Northern Atlantic. But the tephra mostly came down closer to home, although it did reach the Faroer. The fluorine did not travel as far as the sulphate of the eruption: the dry haze which covered Europe had little or no fluorine in it. The withering of leaves described in Western Europe was caused by sulphate.
The fire fountains with the tephra contained 8 Mtons of fluorine. We know in Hekla that the small tephra contained about 0.1% fluorine by mass. Hekla has about twice the fluorine fraction of Laki, so we can assume that Laki’s fine grains carried 0.05%. The total mass of the fine ash traveling more than 50 km is estimated as 1.8 × 1011 kg, which would have carried around 108 kg of fluorine – 0.1 Mton, which is only a small fraction of the total that was erupted. (The rest remained close to Laki, came down in rain or escaped.) This gives an average deposition across Iceland of 1 gram of fluorine per square meter. This amount could be reached with an ashfall of just a few mm.
This level is far above the toxic level which was found from the Hekla eruption of 1947. All of Iceland would have been unsuitable for and even lethal to grazing animals.
[Numbers from Thordarsson but correcting for some obvious typographical errors in their work]
Origins
Fluorine is not a rare element. It is the 13th most abundance element on Earth. It is (in small amounts) essential for our bodies. We don’t have to take supplements, though: there is enough of it in anyone’s diet. The problem is to not get too much. It is like summer warmth: a small amount is brilliant, too much can kill. And Iceland in particular has a problem with fluorine.
Soil pollution with fluorine can happen from nearby sources (natural or industrial), ground water, or fertilizer. Phosphate rocks, such as found for instance in parts of Florida, contain 4% fluorine and this finds is way into the soil. It can remain in the soil for decades as it only very slowly leaches out. But it is rarely problematic as plants tend not to take up excessive fluorine: they leave it in the ground. In some parts of the world, though, care may be needed with drinking water.
90% of fluorine emitted into the atmosphere comes from volcanoes, both erupting volcanoes and ones that are just quietly degassing. And with Iceland responsible for around 8% of the world’s on-land lava production, with higher than average fluorine abundance, Iceland may be the origin of 10% or more of the total fluorine emissions. However, this is fairly harmless as there is plenty of fluorine in the sea and the soil, and the fluorine only pollutes the land if there is tephra that it can attach itself to.
Still, why are Icelandic volcanoes fluorine-rich compared to similar volcanoes elsewhere in the world? It is apparently not uniform across Iceland. The Reykjanes Ridge has normal fluorine, and Surtsey was also lower. Fluorine minerals have been found at Eldfjell. Volcanoes on the main land of Iceland have amounts which can be twice as high. Laki’s magma, from Grimsvotn, was high in fluorine, and nearby Askja is also enhanced. The fluorine content of Eldgja’s lava seems not to be known. Hekla has a particularly high fraction of fluorine. There is something about Iceland. Hekla is the main source of intermediate magmas in Iceland (something like 90%, to be precise), and its fluorine may be so enriched because of this. But it still requires a fluorine source in either the crust or the mantle underneath southern Iceland and Vatnajokul. Hekla is said to be the gate to the underworld. Is it possible that Hekla’s underworld is made of Bluejohn? That would be something.
In reality, the source remains unknown. The presence of apatite in the lower crust, a phosphate mineral that can contain fluorine, has been suggested. But fluorine is often associated with fluid movement and a precise source may be difficult to find. Instead of a specific mineral in the underworld, perhaps the fluorine becomes enhanced by transport or evolution of the magma. There is a lot we don’t yet know.
Us and fluorine
Fluorine is a strange beast. It is highly reactive, but once reacted it can become exceptionally stable. It is used in some of our industries: combine fluorine with carbon, and an almost indestructible material forms with some very useful characteristics. This forms the basis of our non-stick pans, surf boards and skis. Fluorine is used to make our furniture fire resistant. It is also widely used in insecticides, as a carrier for the actual poison. Our fridges use it as the actual coolant.
One may wonder whether it is wise to use an element that can be quite unhealthy so widely. When ozone-destroying chemicals were banned, they were replaced by hydrofluorocarbon gasses. It turned out that they contributed to global warming. An extreme case was HFC-23, which combines fluorine and methane: one gram is as potent as 12 kg of CO2. Production of this (and other) gasses are severely limited but it appears some still escapes into the atmosphere. Recently, attention has been drawn to the ‘forever chemicals’, perfluoroalkyl and polyfluoroalkyl substances, called PFAS. These PFAS are found everywhere. Teflon is an example. Anything repelling grease may use them: think pizza boxes. There are in cosmetics, but also in firefighting foam and scotchguard. We are exposed to them all the time. PFAS are near indestructible and love water. They are now found in our drinking water, whether tap or bottled: none of our purification methods can remove them. They have reached the furthest corners of our world and are found in our seas and even in the polar regions. And just like the fluorine itself, they enter our bodies. Most of us will have PFAS in their blood – even polar bears do nowadays.
Two of them in particular have been linked to health issues: the one used in teflon and the one used in scotchguard. Health risks of low level exposure are not known, but people working in manufacturing of PFAS, exposed to higher levels, have been found to affect their health, and that of their children if pregnant. The worst PFAS are now in the process of being banned. That is beginning to work: most waterproof clothing no longer uses them, for instance. This article describes the dangers, restrictions and fluorine-free developments for firefighting foams. A striking statement in this article about fires close to protected aquifers: “In the event of a fire, the preferred approach might be to allow the building to ‘burn off’ rather than risk using water and/or foam that could make its way into the aquifer.”
One may wonder whether it is wise to spend so much effort making so much of a substance that enters our food chain, cannot be removed from our drinking water, pollutes the entire world and will remain for a millennium. Fragility and stupidity are a dangerous combination.
There have been four eruptions with fluorine poisoning in Iceland since 1700, from Hekla and Laki, most recently in 1970, with impacts ranging from sheep deaths to depopulation of Iceland. It is such a simple element. Are we taking it serious enough? Or have we forgotten? To end with the warning words of Jon Steingrímsson: “I thought it would be unfortunate if these memories should be lost and forgotten upon my departure”.
Albert, August 2024
References
Thorvaldur Thordarson, Stephen Self, Atmospheric and environmental effects of the 1783–1784 Laki eruption: A review and reassessment. Journal of Geophysical Research: Atmospheres, 108 (2003). https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2001JD002042
Thorvaldur Thordarsson, Volatile release and atmospheric effects of basaltic fissure eruptions. 1995, PhD Thesis, University of Hawai’i
Niels Óskarsson, The interaction between volcanic gases and tephra: Fluorine adhering to tephra of the 1970 hekla eruption, Journal of Volcanology and Geothermal Research, 1980, 8, 251-266
Joe W. Walser III, et al, Hidden dangers? Investigating the impact of volcanic eruptions and skeletal fluorosis in medieval Iceland. Archaeological and Anthropological Sciences, 2020, 12, 77
Kenneth T. Koga and Estelle F. Rose-Koga, Fluorine in the Earth and the solar system. Comptes Rendus. Chimie, 2018, 21, 749-756.
Richard Stone, Iceland’s Doomsday Scenario? 2004 https://www.science.org/doi/full/10.1126/science.306.5700.1278
Thank-you for the article on Fluorine, Albert! The dentists advice to use Fluorine toothpaste to increase health of teeth, but hopefully in less density than in Iceland’s Fluorine tephra.
A great view on the current eruption allows this webcam on Vogastapi: https://www.youtube.com/watch?v=Hia5Ejq2778
The view on the eruption reminds me to Fimmvörðuháls lava fountains. Can we compare the strength of this eruption with Fimmvörðuháls?
Its way stronger, the lava is also a lot more fluid, it forms a’a from high flow rate but it is as fluid as the stuff in 2021 now.
“indicating that about 30% of the fluorine (8 Mtons) had degassed from the magma. This is not surprising since at normal temperature and pressure, fluorine is a gas. (The boiling point of F2 is -140C.)”
Fluorine in magma would be degassed as HF, which is a liquid at ambient temperatures (not in magma obviously). It is hydrogen fluoride, same as water is hydrogen oxide compared to elemental oxygen. Fluorine with a boiling point of -140 C is the elemental F2 and there is a beyond 0 chance that is present in the magma. It is basically everything that is dangerous about pure oxygen, but 10x more.
This is a brick burning in F2.
https://youtu.be/wqLnSkLalOE?si=g318yJuhtDjMGlt0
I remember seeing something about using fluorine as the redox active part of a very powerful rechargable battery, instead of a positive element being the active part like is typical, but it hasnt shown up in the real world. Most things involving fluorine in elemental form never leave the lab…
The boiling point of HF is pretty low, at 20C or so, and below that it will still remain a vapour at low partial pressure. The point is that fluorine in its common form is quite volatile, and so it is understandable that much of the degassed fluorine escapes into the atmosphere. Yes F2 is not expected in nature – the post mentions HF.
The boiling point of HF has been added to the post
There are reasons.
https://www.science.org/content/blog-post/sand-won-t-save-you-time
If you think that’s bad, there’s an even more reactive fluorine compound that could set fire to a comet nucleus out past the orbit of Jupiter:
https://www.science.org/content/blog-post/things-i-won-t-work-dioxygen-difluoride
It’s notable that the early experiments with these god-awful molecules mostly seem to have been performed by the Nazis. As strong a hint as any that they are best not messed with.
F2O2, ‘fluorine peroxide’ although the more positive side of the molecule is the oxygen, not the fluorine. So it is a positively charged peroxide bond… 🙂
OF2 is a thing too, oxygen difluoride, it is room temperature stable but only in isolation. Apparently OF3+, with oxygen in a +4 oxidation state, is theoretically stable but would react with F- to make OF2 and F2. Or with anything else even faster. So it isnt possible to create it.
The thing that is maybe most scary, is that dropping a common 9v battery in HF would evolve F2…
Interesting:
Source: https://www.livefromiceland.is/webcams/vogar
Mostly hot gases with a bit of ash interacting with colder moist air to make clouds?
The volcano made its own weather!
You could see it best on Sundhnukar second view (Live from Ice) from a distance.
Hot gases rising, reaching a humid layer of air, SO2 plus any dust greatly speeds up condensation, thus large cumulus clouds form, and in fact they began pouring rain right on the spot!
Acid rain, I suppose.
And fascinating. 🙂
(Wouldn’t it make much more sense if *moist* gases were rising into a *cold* layer and then condensate?)
It’s more that the rising warm and moist air *itself* expands and cools as it rises until it reaches its dewpoint temperature, and then the water vapor condenses out. The colder the surrounding air that the plume is rising into, though, the greater the buoyancy and associated upward acceleration of the plume.
Think both are true.
Yes, indeed. I would add that there’s plenty of water vapor in the volcanic plume itself, in addition to that already in the atmosphere. As it rises, the air in the plume expands and cools, and the water vapor within it condenses, forming the cloud. Similar “pyrocumulus” clouds form over forest fires.
Indeed the surrounding air is quite moist. Here is the atmospheric sounding for Keflavik:
Weather forecast; Volcany with a chance of skin burn. 😀
This is too nice.
Pileus clouds!
The Sundhnúkar webcam shows lava fountains that remind to best times of Hawaii’s eruptions:
Maybe this link to “livefromiceland” is better:
https://livefromiceland.is/webcams/fagradalsfjall
A great article, as always, Albert – thank you!
I was at the BlueJohn cavern 10 weeks ago, and did the Mam Tor/Great Ridge trail. It’s not cheap these days (the cavern) but it’s almost otherworldly inside, with it’s eerie blue glow. If you’ve ever seen the film ‘The Descent’ or read H.G. Wells ‘The Time Machine’ you’ll understand what I mean
So many memories of the wonderful places in God’s own Earth. Now I’m in my 70’s, I can’t do any of the things I used to (insert fatuous sexual reference here) – but at least I was at the County Ground today to witness Derbyshire win their first home Championship game in Derby for 5 years.
Another wonderful memory to add to the collection.
Its a fun eruption.. althrpugh far far from “jesperian” in scale thats for soure. to get me really hyperactive happy thrilled it woud need to be a new siberian traps, camp or a new chixculub event somewhere on Earth, Im picky…and more and more crazed and bored…still hopes to live in Iceland one day
Isak Live stream just finished and he flew past this sign on the way there!
Video for replay below
Re the sign, a bit of dry humor from RÚV:
Lava flows over old munitions (25 Aug)
😀
Would craters by this considered as pseudo-craters?
It feels like Iceland is taking a page from La Palma’s book right now. Two of the fountains have been exceptionally tall today and pulsating very much like that eruption. It’s spectacular! See, e.g. https://www.youtube.com/live/804nPrAUAxg?si=iyfGzdG652g9yNd6
How tall are those fountains?
I can’t begin to imagine what the Laki ones were like at their most intense phase. Fountains 2000-4000 feet high? Even if its an exaggeration its still mind blowing.
500 meters was sustained at a few points, and I think 800 meters at the highest. If there was anything over 1 km it was not long lived but water interaction could have done it at times, there is a tuff cone among the Lakigigar.
Should say though but only a short section was this powerful at any time, and most of the Lakigigar cones are not really unusually big. Laki was never a 20 km long curtain of fire, although the eruption rate was on average about 700 m3/s, so flow rate was not unlike the other days fissure but stayed that way for over half a year with much higher peak.
And now there is the moon rising (don’t know why):
https://livefromiceland.is/webcams/thorbjorn2
I do wonder, with how high the fountains are if maybe the eruption will be short lived and end this week instead of lasting for many weeks as did the last two. The fountains are very powerful for being now beyond the first stage of eruption with high pressure. Although it does look like the GPS isnt levelling off after the first stage like the others.
At this rate though there will be a new small mountain to name, the cone must be at least 40 meters tall which is huge for this area.
75m – 150m according to Þorvaldur Þórðarson. https://www.mbl.is/frettir/innlent/2024/08/26/thorvaldur_ovenjulegt_gos_ad_ymsu_leyti/
That woudd put the cone at about 50 meters tall then and over 200 meters long, if not more. Its not much by world standards, but theres basically nothing more than 10 meters tall in the area otherwise so that is very significant.
To be honest, it might well be much larger than that, it will be interesting when the maps finally update to let us see it all, but that might be in a year or more 🙁
Thanks Albert, a fine read!
Forgive me a little if you can, I’m a chemist who has worked with fluorine-containing compounds from time to time, although that’s fairly incidental as that’s not been by R&D field.
When you mention CaSiF4 that seems to be a mistake, the compound is CaSiF6. On the other hand SiF4 is a common gaseous component of volcanic gases.
The use of fluoride in tap water and toothpaste is due to the incredible stability of calcium fluorapatite (the search engine AI just told me its solubility product constant Ksp is 3.19 ± 0.14 × 10^(-61) mol/l at 37°C, which is ridiculously insoluble.) So converting any apatite (Ca5(PO4)3OH) in tooth enamel into fluorapatite (Ca5(PO4)3F) does good things for your teeth.
On the issue of PFAS it’s my belief the whole thing is incredibly overblown. Any of us who’ve lived since the Apollo moon landings have historically been using Teflon-coated kitchenware, especially frypans. When you fry something with some oil in a Teflon frypan the coating slowly degrades under heat and oxygen and the degradation products such as perfluorooctanic acid (PFOA) dissolve in the oil. Which you then eat. Eventually the coating would become too eroded and food would start sticking to the frypan – whereupon you’d throw it away and get another one, but only after having effectively eaten the coating in your food!
For much of the last fifty years therefore a very large number of people have been ingesting vast amounts of PFAS. And no they haven’t been dying of it, as far as I can tell. Rather life expectancy has been rising over that time.
PFAS is excreted from the body, albeit fairly slowly. Depending on individual body chemistry the half life seems to be 5-20 years. Teflon for kitchenware has now been banned, which I have no especial issue with, but the empirical evidence seems pretty clear to me that PFAS isn’t particularly harmful. It is though a mysterious chemical that the media can get excited about, and which their readers who aren’t chemists like me can become fearful of.
Bruce. Thank you for this. One thing that continually bothers me is scare stories usually based on very limited evidence that often does not even support the abstract developing into news-scares that power draconian regulation. Not only can this waste world resources dealing with a non existent problem, but often the replacements turn out to be even worse. The real problem is that substances that do not hit the eco-scare level are completely ignored (often for decades) when they should have been banned earlier. Also urban myth abounds even in scientific circles, one classic one (there are others) is pesticides which since the 1970’s (largely following Silent Spring) have to be (rather rapidly) biodegradeable and that includes degradation products (and their safety too) yet they are invariably quoted as pollutants whilst ‘natural’ ones tend to be ignored even if they are far more toxic and persistent.
Rant over.
We have had one close escape when fridges were designed to use chlorine rather than bromide. That meant we had time to safe the ozone layer. If the other choice had been made, a century ago, we would now not have an ozone layer. The only reason for that choice, I believe, was that chlorine was a little cheaper. We should not assume that something will be harmless: we should test before committing. There are many unwarranted scare stories around (I mentioned the ones about toothpaste) but there are issues on the other side as well
Thanks! I always love to hear from the experts. Every time I learn something new. The evidence that two of the PFAS are harmful does not come from their public use, but from people working in the manufacturing of them. They are reported to have higher incidences of cancer and that pregnancies lead to lower birth weight than comparison groups. I have not researched the details but the evidence must be compelling for these two to have been banned. Very few of the other compounds have been tested for toxicity. With these compounds with will stay with use for a long time, it is better to be cautious. Fluorides in teeth are okay at low levels but it is not good at higher levels. There is even a term for teeth affected by fluorosis. The existence of fluorosis shows that fluorine is something to be cautious with. Living organisms are very poor in taking it up, but only up to a certain level. I expect that in the large flood basalts, pollutants such as fluorine and mercury made large areas unlivable.
https://en.m.wikipedia.org/wiki/Fluoride_battery
On the topic of fluorine chemistry, this is one area that is promising in the future, although its unclear if this will ever be a common item. I mentioned earlier about it in a comment to Albert.
I guess the challenge of finding an electrode material that can hold neutral fluorinr atoms with high stability is a challenge. I do wonder if a Li’ion that uses CoF3 or NiF4 is possible, both being stable but with very high redox potential. Maybe not CoF3 to avoid using cobalt but still, LiF has an extremely high heat of formation and also a very low activation energy, meaning it is efficient and should allow high power charging. I guess working with fluorine is a big barrier to this research…
The more this goes on, and especially now more tha ever, I an starting to think this series of eruptions is not exactly a repeat of the last cycle. I dont find it realistic that eruptions with the frequency we see now would be missed back in the Medieval times, maybe not well observed but the volcano is hardly inconspicuous.
The style of eruption is also not really like the last eruptions either, Eldvorp was a curtain of fire but never became persistent, and Arnarseturshraun was persistent but seems to have been a little of its own thing, on a different parallel dike to Eldvorp, and was a lot shorter continuous fissure. The two are also separated by much more than a month too.
The cones created now too are much larger than the old Sundhnjukur cones, actually there is basically nowhere on Reykjanes that shows evidence of sustained tall fountains and yet that is exactly what we see right now, and sort of in 2021. The lava apparently is pooling behind the cones and so actually could rush out and reach the road and even ocean if it finds a way to drain soon.
And still, most importantly the lava composition is not homogeneous with the lava erupted in the last few cycles, it is hotter and originates deeper down. In May and June it was said the magma composition changed from being stored crustal magma to being the same stuff from 2021 with minor evolution. That could be why the fountains are so strong now, volatile rich magma. But the fact nothing like this is evident for millennia is telling, I dont think the past is as reliable an indicator as we thought.
The difference could be that apparently a fairly large body of magma (it is estimated to be 50 around km3) has been deposited in a depth of 9-13 km. So there is a lot of magma available to continously replenisch the shallow reservoir at Svartsengi.
I guess in the previous cycles there was a smaller body of magma in the crust, so it took longer for the shallow sills or pockets to be refilled, hence eruptions were more infrequent.
I also think (speculation alert!) that the current eruption is using the same dyke to erupt because of the short time frame between each eruption. If the timeframe between the eruptions would be longer, we would probably see different dykes and more monogenetic eruptions.
The 1000$ question is how long the deep reservoir will continue to feed the shallow magma pocket at Svartsengi. Will activity shift to a different volcano? And when? But given the size of 50 km3, the eruptions could go on for quite some time and they might grow into something really substantial over time.
I guess we should expect maybe 5 km3 of lava to erupt in the next few centuries, possibly more as the 10% rule is a bit loose and probably not as applicable to a slow ridge with a large magma generation like Reykjanes.
Thing is, at the current rate, since 2021 there has been about 0.3 km3 of lava erupted. 0.28 km3 before this week, and about 0.15 km3 from Svartsengi so far. That is a rate of about 0.1 km3 a year on average.
To get 300 years of activity like last time either gaps between eruptions or rift sequences become a lot longer than a year, or we are looking at a much bigger episode than was seen 1000 years ago, 0.1 km3 a year for 300 years would be 30 km3.
This night Krysuvik had an earthquake swarm. Is it possible that sooner or later the “Fires” expand there? It is on the east side of Fagradalsfjall. If we imagine, that the Sundhnukur sill started from Fagradalsfjall’s depth, there might in future also go something east.
Maybe the Fagradalsfjall eruptions 2021-2023 were an indicator that this Reykjanes Fires Cycle has more magma than the Medieval session.
More than the location I think is the chemistry, it was different from the Medieval lava. It looked to be going back to that for a while but now returned to the first stuff, although it evolved slightly as olivine settled out in the sill. Will be important to see the composition now if it is the same, but the intensity of the eruption even right now makes me think the stuff is rising fast from depth to the sill.
https://earthice.hi.is/eruption-sundhnuksgigar-march-2024-chemical-analyses-lava-samples-and-volcanic-gas
Found a paper of the analysis of the lavas, albeit during the March eruption. It shows, at least according to them, the magma partly degassed before it even erupted. Maybe things changed with the last two…
https://www.geochemicalperspectivesletters.org/article2417/
Another one on SO² budgets of the recent eruptions and the Medieval eruptions.
With the Medieval experience we have a small random sample of the whole variety what the Reykjanes peninsula with all the systems can do. Frequently active volcanoes like Hekla, Askja and Grimsvötn allow more representative samples of eruptions to be collected. So the probability of the Reykjanes Fires to erupt in a certain way is unkown.
It is possible that we’ve witnessed the beginning of a certain class/type of Reykjanes Fires that hasn’t been discovered yet. The unusual chemistry of the magma and the Fagradalsfjall eruptions (after 8,000 years) might indicate a rare type of Reykjanes Fires. Fagradalsfjall is Iceland’s western most shield volcano (Þráinsskjöldur). “The characteristic volcanism formations are lava shields” (Catalogue description of Fagradalsfjall). This typical behaviour of Fagradalsfjall’s system may influence the future development of Svartsengi/Sundhnukur which likely depends this time on Fagradalsfjall’s deep magmatic system.
Fagradalsfjall has pre-historical craters on the NW base of Fagradalsfjall Plateau towards Nautholaflatur. There the lavas from Fagradalsfjall overlap partially the lavas from Sundhnukur craters. The fissures and craters of both systems can come very close to each other.
It’s possible that we in future get a common shield structure by Fagradalsfjall and Sundhnukur. Fagradalsfjall may help Sundhnukur to act more like a shield volcano than 2000 years ago.
I think it was just in the common updates but the lava in May was not the same as the lava before from Svartsengi, it all comes from the same parent magma as the Fagradalsfjall lava but evolved in the sill, but not so the last two times now it seems the sill is mostly flushed through. Which I think is pretty obvious with the height of these fountains and the abundance of pahoehoe around.
You are not the only one who is puzzled:
https://www.mbl.is/frettir/innlent/2024/08/26/thorvaldur_ovenjulegt_gos_ad_ymsu_leyti/
Perhaps we should look more at earlier eruptions eg pre-Holocene
Anyone got an up to date lava map? I’m wondering for far off the northern road/vogar the lava is.
Reporting on the eruption seems to have went quiet on all the usual sources (vedur, mbl, ruv), maybe they’re bored with it already!
There is an IMO update. Already.
I think there must be different servers with different updates. The last one in English I can see is from 23 Aug. It’s not the first time I’ve seen comments here on IMO updates that only become visible to me a day or so later.
There is an Icelandic one and an English page. You can choose the language on top of the IMO webpage (which is a riddle inside an enigma).
The Icelandic pages tend to get updated more regularly. From the map Zach has posted below from the Icelanduc pages of IMO, I would estimate about 4 km to the road from the most northerly point. It could probably be estimated more accurately by superimposing on Google Earth.
I’ve only read/heard about Fluorine in ash/tephra. Does lava has the same density?
Fluorine is apparently a characteristic element of Iceland’s mantle plume. Has each plume on earth its single individual chemical fingerprint like this?
IIRC, such fluorosis has been blamed for the utter collapse of Minoan civilisation.
Yes, most got out ahead of Thera / Santorini’s cataclysmic eruption. Yes, their beached ships and port towns on Crete’s northern coast were probably razed by tsunami train. Even so, the Cretans seemed to go into rapid decline, were a ‘push-over’ for the later ‘Sea Peoples’.
Fluorosis would blight cultivation and herding for several generations, leave survivors debilitated…
Do we know how badly the ~70kyr Toba mega-eruption distributed Fluorine ?? I’ve read that, due seasonal winds, the ash-fall could have been *much* worse across Africa had the blow fallen six months earlier or later. Even so, looks like only coastal hunter/gathers, gleaning from wave-washed shores, did well…
Toba is an evolved subduction arc volcano rather than mantle-plume fed, I think it is some form of crustal contamination on the way up from the magma that determines fluorine content. Thordarson has not only written on Laki but also on Columbia River Flood Basalts (paywalled)
https://www.sciencedirect.com/science/article/abs/pii/S0377027396000546
https://www-vedur-is.translate.goog/um-vi/frettir/jardhraeringar-grindavik?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-GB
It is kinda official: it us the largest eruption of the series yet. The ground is still deflating though, so it might continue until either the eruption weakens or ends.
The eruption has covered nearly the same territory with lava in the northern part as the Fires during Roman Age which is displayed in the map layers (Reykjanes-Svartsengi lavas) in this map: https://icelandicvolcanos.is/?volcano=REY#
The only part what is missing, is the more distant prehistorical northern fissure on the NW slope of Thrainskjaldarhraun. Future eruptions of Sundhnukur can still plop up in this shield volcano of Fagradalsfjall. There both volcanoes/systems touch each other.
Fluorosis is a cause of concern and the subject of research in Ambrym, part of the Vanuatu chain.
https://link.springer.com/article/10.1007/s10653-010-9338-2
it is a concern in Goma as well. Unfortunately can’t seem to find the article.
See https://www.researchgate.net/publication/324135733_Natural_hazards_in_Goma_and_the_surrounding_villages_East_African_Rift_System Levels are high in one particular river in the region. As in Ambrym, the main symptom is in teeth.
Has anyone been able to obtain a reliable estimate of the height of the current fountain on the left? This was taken 21:43:28 local time today 26-Aug-2024. See
as that fountain seems quite high and vigorous.
Yes, the left one is currently the “boss” of the lava fountain family. To determine the height, we need to know the distance of the webcam from the lava fountain and the subjective angle between the bottom and top of the lava fountain in the visible view of the camera.
Now, at night, it’s possible to observe the eruption better than during the daylight, when vog and steam disturbed the view. On the Vogastapi webcam I count five lava fountains. Four of the lava fountain build a dense quartett like a short but powerful curtain of fire. The energy of the lava fountains reminds to the eruptions of Fuego, but enduring. Occasionally it looks like lava flashs that burst out of the craters and flood around.
With Fagradalsfjall in the background from the Vogar camera and with the highest bursts today reaching roughly that height (390 m), the eruption being halfway to Fagradalsfjall and the ground surrounding being at 50 m, we can calculate that those bursts were at 390/2-50 = 145 m high.
The burst yesterday night were even higher than that…
Stærsta eldgosið á Sundhnúksgígaröðinni = Biggest Fire Gush (Gush has most close etymology to “Gos”) at Sundhnuksridge https://www.vedur.is/um-vi/frettir/jardhraeringar-grindavik
The tendency of increasing size/force of episodes continues. On first day the eruption extruded 1,500-2000 m3/s. The lava field (already 15 km²) has covered the area of Kálfell (cabbage or coal hill?) and the slopes of Fagradalsfjall shield volcano Þráinsskjöldurhraun.
On first day (31st August 2014) IMO wrote about Holohraun:
“A lava eruption started in Holuhraun shortly after 04 AM, on the same volcanic fissure, which erupted earlier this week. The fissure is estimated to be 1,5 km long. It was detected on Míla´s web-camera at 05:51 AM. Fewer earthquakes seem to follow the event than in the previous eruption, but more lava is being extruded.
At 07 AM the lava flow was around 1 km wide and 3 km long towards northeast. The thickness was estimated a few meters, the flow about 1000 m3 pr second.”
This means that the current eruption was on the first day stronger than Holohraun on first day.
Yes the big fissure eruptions are not necessarily more intense just last a lot longer at high rate. Even Laki was dwarfed in intensity by the Mauna Loa eruption of 1950, but that only lasted a few hours at that rate and then slowed way down where Laki was at at least 300 m3/s basically the entire 8 month duration. Eruption intensity is the important factor and it needs to be considered separate to the volume. Theres a very big difference between 10 km3 in a century and 0.1 km3 in a day, but only one of those sounds impressive without observation.
Laki was not constant during the 8 months. The main eruption period lasted 5 months (June-Oct) but with bursts of activity. It is likely that it behaved like most eruptions, with highest eruption rates at the start of each phase. Comparing the average rate over 8 months with the few hours of Mauna Loa may not show the full picture. Of course the Laki eruption itself was not observed, so we don’t know, but just the haze covering western europe in June shows how strong this phase must have been.
Yes thats true, but the dats I have seen fir the first part that was the highest effusion rate is about 6000 m3/s for a few days. Which is crazy, 3x more than we saw the other day at Sundhnjukur and from about half as long a fissure too. But even that is still probably under 1/3 what Mauna Loa did on the first night of its eruption in 1950, which using the numbers from HVO directly, erupted at close to 20,000 m3/s in the first 3 hours. And unlike Laki was an actual continuous 20 km curtain of fire 🙂
Hawaii, as it turns out, is apparently very low in fluorine, and very high in sulfur. Although so is Bardarbunga, the center of plume volcanism in Iceland.
The thing that jumps out to me is that the volcano most obviously connected to F- poisoning in Iceland is Hekla and it erupts mostly andesite and basaltic andesite. Eyjafjallajokull in 2010 also erupted andesite high in fluorine. And you mention Askja and Grimsvotn in the post, those are basaltic but the basalt is not primitive. Unlike Bardarbunga the basalts of most other Icelandic calderas have extensive storage and residence time in the crust. Laki is pretty clear evidence of that, Grimsvotn isnt big enough to have survived something like that alone, the magma was from its deep plumbing.
So fluorine, likely as mostly HF, seems to be concentrated in evolving magma. Maybe not surprising given the chemical similarity of HF to water which we know is concentrated in more evolved magma. Maybe making a map of Icelandic volcanoes that shows both F- concentration and the MgO percentage in the basalt could be very insightful. I have a suspicion that those two negatively correlate.
Hekla is responsible for 95% of evolved lava in Iceland, so that is a clear connection, where fluorine is higher in intermediate lavas. The fluoride enhancement though is not just measured with respect to MgO. It is studied in comparison to chlorine which degasses and evolves in a similar way. That shows enhanced F/Cl ratios in southern Iceland and Reykjanes but not on the Reykjanes ridge. This analysis does not depend on the absolute abundance of F in the lavas. The data is quite limited though. The conclusion is that fluorine is enhanced in magma from at least part of Iceland, relative to similar basalt elsewhere in the world, but details and cause are unclear.
I was more considering that an investigation be done if F- negatively correlates to MgO in tholeiitic magma. I once did wonder if maybe Hekla sat above a local bit of crust with weird composition, maybe a continental fragment. But that was back before I was aware that most Icelandic volcanoes are actually not really primitive, and do show significant evolution. Hekla actually is one of the more mafic areas although the central volcano obviously isnt, but its related basaltic vents are highly magnesian like Bardarbunga and Reykjanes, and also Hawaii (all 7-10% MgO). Compared to Katla, Grimsvotn, Askja that are all about 4-5% MgO, including Laki and Eldgja, I made a map of this once that I might be able to find.
In the northern part the current eruption has already covered the whole previous pre-historical lava field (Roman Age). I didn’t expect that this happens so fast. Should we expect that next eruptions expand the lava field a lot beyond the old Sundhnukur lava fields? Has a northern ocean entry ever happened during Holocene from Sundhnukur eruptions? Maybe only the “Fagradalsfjall type” of shield eruption can do this … if we get one.
The question for next episode (Christmas?): Will it expand to the south like 2500 years ago and bury Grindavik or will it to more in the north contrary to 2500 years ago?
Volcanophil: “Kálfell (cabbage or coal hill?)”
It’s with a double “f”, Kálffell, that is, Kálf-fell. So, likely not cabbage (kál), but calf (kálf).
Now known as Veal Hill, I guess
“Kalfjäll” in Swedish. Kal = barren, fjäll = mountain. Above the tree line. Veal Hill sounds kind of funny tho. 🙂
Wait, you guys are probably correct. I missed the “f”/”v” thing in Icelandic. Calf is “kalv” in Swedish. Kalvfjället.
Kálfell is most likely to be translated to “balled mountain”, i.e. that nothing is growing on it.
“Balled”, or *Bald*, = “skalli” in Icelandic?
As a baldy, I take these things *extremely* seriously and am pleased to have a fine hill named after my condition in Fjallabak! 😉
Mt. Awu on Sangihe in Indonesia currently experiencing uplift of 2 metres a year for the past 3 years, which is the strongest uplift we know of at the moment. It’s been experiencing some seismicity recently also going off the Smithsonian reports.
I watched the GeologyHub’s video and see no source for that metric. I am not saying he’s making it up but I would like to have easy access to his sources so I can check on it myself and not was time combing through unfamiliar websites for one specific report.
He often doesn’t refer directly to any source in his videos, but I do find his voice, well….. annoying!
The eruption is building up quite a massive cone now, it is taller around the south vents but is centered most around the jet-like fountain at the north end. Videos I have seen recently show the lava is still fluid and fast but doesnt go to far on the surface, it seems a lot of the lava output is going into building the cone up instead of flowing away.
Unless this evolves into a lava lake and a tube fed pahoehoe flow I cant see this reaching the road or ocean now but it could create the biggest cinder cone in southwest Iceland and right where everyone visiting can see it too. Maybe it has actually already got that far and is just showing off now 🙂
Well, it seems to already be visible from the road to Keflavik based on the Vogar cam.
Yes it seems that is true. It could be used to find the cone height too, at Vogar the cone looks about 1/4 the height of Fagradalsfjall, which is about 385 meters tall, so maybe about 100 meters. The cone is also about 2/3 the distance from Vogar as Fagradalsfjall, making it about 60 meters tall. So summit is about 120 meters elevation or only a bit lower than Stori Skogfell.
Best guess realistically is that the cone is 50 meters tall at least by now. And that the fountain pushes over 100 easily when it becomes jet-like and more vertical. It was probably over 150 meters at times the other day.
I wonder, I know only little of geology. But at the geology map here: https://arcgisserver.isor.is/?lon=-22.35624&lat=63.90567&zoom=13&layers%5B%5D=geologyBaseMap&layers%5B%5D=names
it appears that this cycle of eruptions have occured near the red dots (scoria ash, old eruptions) on a line north east of Grindavik. If we follow the direction from Grindavik through the red dots into the middle of the large blue Thrainsskjoldarhraun, there are some red dots at a place called Eldborgir. Could it be that the eruptions move further north east in the following months/years, and we may see eruptions up there?
It could, although getting that far would require the rift to extend that way which would require a lot of pressure. Probably more pressure than it would take to send magma u der and probably erupt in Grindavik or in the ocean instead. That is one concerning thing about this now, go south of the start point the same distance this eruption is, and Grindavik meets the same fate as Leilani Estates. Its never a certainty until we see it in action but still…
I think Eldborgir also basically just means spatter cones, not really a formal name. Its really hard to even see anything there without an overlay to guide. So this might well be too far out to get a big volume but then that logic said what we see now is near impossible so we are in uncharted territory now really.
Has anyone noticed a 6 microrad increase in tilt in the last 2 days at IKI. Over the last year, IKI has often outpaced the UWE since the ongoing series of intrusions since this time last year. None of the other tiltmeters in the area are currently showing any significant tilt. I remember Chad floating around an article that said the 1959 Kīlauea IKI eruption was a result of a pulse deep magma rising to the surface after the lull in magma production after the 1924 explosion. What would a lead up to a new eruption in Iki look like with the dyke bypassing the south Caldera magma chamber?
I had noticed it yesterday. Also saw some changes at KAE Tiltmeter, SE of Kilauea, near the coast.
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There was a major storl in Hawaii recently, I saw the tilt too as it shows on all tiltmeters pretty much but this time I dont think it is magma.
That being said Kilauea has recovered from its recent little intrusion and will probably do a repeat soon. This time might just about do it and erupt. Or the middle ERZ gets full supply soon.
Correct. The torrential rain from the hurricane has inflated the ground and affected the tilt. Wet ground expands. There is another storm heading for the region, so it could happen again.
The tilt signal up at UWE is probably real though. The faster tilt from the rain is visible but doesnt overshadow the volcanic sjgnal of ongoing uplift at the summit. It is still going up pretty fast.
In the recent GeologyHub vid talking about 6m uplift at Awu he showed a graph of uplifting volcanoes, Kilauea should have been on there at 3rd place this year. Since last September parts of the south caldera have lifted up nearly a full meter. It hasnt been doing this for years like Iwo Jima but still it is very significant and at any other location would be a massive sign but apparently not in Hawaii. I do worry that HVO are trying not to alarm the residents but are unintentionally being too cautious and unrealistic about the situation.
Hurricane Family, all moving west:
https://www.nhc.noaa.gov/?cpac
The HS02 GPS station still showing deflation.
I wonder if this is helping keep the two fountains very high?
The eruption still has been quite seismic, it forced it’s way through. I wonder if in doing so it established a better connection to the intermediary sill, perhaps by developing a wider channel for the lava to flow through via rock breaking/melting. Previous eruptions were squeezed through like toothpaste.
The weaker the ground has become over time the more likely the connection can be sustained.
Does the relatively gasrich magma allow the development of something Strombolian like Fagradalsfjall 2021 (f.e. “Lava Geysir”)?
Holohraun had (after one week) an average rate of 100 to 200 m³/s. Does this align to the present rate of Sundhnukur?
The last update described the rate as tens of cubic metres per second.
As far as I know, most of the seismic activity after the initial swarm was from extending the dyke to the NNE. The initial swarm was similar to previous episodes.
I agree, that’s the most likely explanation.
Here are a couple of interferograms that cover the timeframe of the eruption start and the first couple of days. One from descending orbit and one ascending. We can clearly see that there is a new dyke stretching from Sýlingarfell/Stóra Skogfell out to the currently active fissure. Note how the two lobes corresponding to the dyke switch which one is moving towards or away from the satellite depending on the orbit. That’s because the main deformation is horizontal and away from the dyke. The deflating sill also shows up very clearly. The ground on top of the sill is moving away from the satellite in both orbits, meaning that it’s mainly vertical deformation. Since the ground is contracting, there are also some horizontal movements as well. That’s why the center of the purple blob moves slightly towards the satellite between the two different orbits.
It seems like the widening of the dyke is very small in its southern end and that the maximum widening is right where the eruption is now happening. A possible reason for why it went north could be that the previous strain release in that area was much smaller than for the part where we have already seen several eruptions. That could have allowed for a wider dyke to form in this place and the wider dyke allowed for an easier path for the magma, which effectively shut down the eruption in the southern end.
If the images don’t show, it’s probably related to security settings in your browser, since the images use http instead of https, and browsers have lately become reluctant to mix them up.
Ironically, they don’t work for me and even worse is that it doesn’t display the links. Let’s try again with the http part stripped out.
brunnur.vedur.is/pub/vincent/insar/ifg/csk_reykjanes_A33-krysuvik_20240817-20240825_unw.png
brunnur.vedur.is/pub/vincent/insar/ifg/csk_reykjanes_D44-krysuvik_20240816-20240824_unw.png
I have had the impression that the eruption followed Mauna Loa’s pattern: 1. a summit fissure, 2. a rift zone fissure. During the first 5-6 hours the shallow summit of Sundhnukur was active. After this a new fissure opened on the northeastern rift zone similar to Mauna Loa 2022.
The small size and shallow structure of the Reykjanes Peninsula volcanoes hide the structure of a central volcano and fissure swarm that’s common for normal Icelandic volcanoes. But if we look at the dynamics of the recent Sundhnukur eruptions, they show a central volcano vent that tends to erupt first before the eruption migrates towards a location on the fissure swarm.
Other central volcanoes in Iceland have fissure swarms that run straight through them. Here, we have a shallow magma storage that sits in the middle between two separate fissure swarms, none of which cut straight through the magma storage area. The eruptive fissures are all along that first dyke that was emplaced in November, so I would consider it the same fissure.
I think the eruptive activity at Reykjanes is entirely controlled by rifting. Then there just happens to be a sill that acts as a pressure vessel that modulates the time between each event, similar to how the pressure tank in a fresh water well system can control the pump cycle time.
Anyway, I don’t think you can call it a central volcano, but it might turn into one in the future.
On Facebook I saw a sketch that showed a Y-shaped dyke from the sill. First there was the dyke towards Sundhnukur (maybe magma used an established route there). Around six hours later a new dyke came up from the sill towards the NNE.
Yes, and I never understood the rationale for drawing it like that. In my eyes it just looks like the dyke was lengthened. The progression of quakes was from south to north the entire time. It didn’t really go back and start over, it just had a short pause after 10pm, and another one around 1am, but other than that it just pushed on with a clean progression from south to north.
From the interferogram it is evident that the largest expansion happened around the current eruption site. I think that’s the simple reason why it’s erupting where it is. It’s the widest and easiest way to the surface. No need for a separate conduit from depth.
On the central, most frequently active part, the conduit is maybe still relatively open for magma. There is less counter-pressure for rising magma than in the colder and since 2500 years dormant northern parts of the fissure swarm. Before the northern part opened, magma used the weakest path again.
The central part is also the part that prior to the eruptive sequence was under the most strain, since it is the midpoint between the two plates pulling in opposite direction. It wants to break there (same thing applies to Fagradalsfjall 2021). After enough strain has been released in that area, the maximum strain is found further out, at least that’s what I’m speculating here. I do realize the implications that has for Grindavík and the potential for the fissures to extend that way. I hope that enough strain was released by the graben formation and that any further strain release along that particular stretch of the rift is released further west. More specifically at Eldvörp. Time will tell.
https://youtu.be/Ihx_xyIh7-4?feature=shared
Video of the lava flowing over one of the fault scarps downhill of the vent a few days ago.
The lava is forming an a’a surface from the high flow rate and turbulence but it is pretty clear how fluid the lava is, its the same sort of stuff as in 2021 but flowing at a much higher rate.
We’re approaching the 10th birthday of Holohraun. Fortunately Iceland celebrates with a nice firework this date. On this page you can follow the steps during End of August 2014 towards the eruption: https://en.vedur.is/earthquakes-and-volcanism/articles/nr/3000#ag28
Today 10 years ago IMO published this observation:
“Since yesterday, the length of the dyke under Dyngjujökull has increased by 1-1.5 km to the north, which is considerably less than in the last days. The dyke has now reached the fissure system of the Askja volcano and GPS measurements indicate that the area there is greatly affected.”
It was the day before the eruption began on August 29th.
I flew out of Iceland on the day the dyke started forming.
The first significant earthquake swarm that alerted scientists, was on 16th August. It took 13 days until the first eruption happened. The dyke went immediatly to the north. As far I can read, there was no subglacial eruption or intrusion in the central caldera before the dyke towards the northern fissure system started.
It started by heading southeast towards Grimsvotn. The assumption at the time, was that the contact with Grimsvotn’s fissure swarm pushed it back north. Before it passed beyond Vatnajokull. A couple of cauldrons formed, possibly due to a sub-glacial eruption that was never confirmed as far as I’m aware. I flew out on the 16th and came across the first indications a day or two later. That was when I found Volcanocafe.
I think in hindsight, ir was less that it came into contact with Grimsvotn and more that it found a suitable place to rift, a pre-existing graben abd lower down. Grimsvotn was still recovering from its eruption in 2011 at the time, and Askja was dormant at shallow levels, Bardarbunga could have dominated them quite easily but it didnt and the eruption was in the low area between the volcanoes.
I think the same thing happens at Veidivotn, the fissures at Torfajokull are often slightly misaligned with the ones from Bardarbunga, and there isnt really any major en echelon trends at Veidivotn otherwise. Bardarbunga is the major player but I think Torfajokull does erupt on its own, it isnt a zombie volcano kept alive by Bardarbunga, or by Hekla as I have seen claimed too. Its recent inflation does give come consideration about this too, it doesnt go big by itself at least not recently but if Veidivotn rifting is initiated here it could be somewhat unrelated to Bardarbunga, meaning a big rift could be sooner than I thought. At least, this us how I interpret things.
Did the north moving dyke create a graben? I imagine that some cauldrons in the ice could be caused by a subglacial graben.
I think the fact that the dyke seemed to reach the Askja fissure swarm backs up hindsight Chad.
On terms of a graben, one did form along the dyke, but I don’t think that was the cause of the cauldrons that formed in the ice. I remember them being pretty large and they were also circular not straight.
I remember watching the huge surges of molten lava splashing back and forth in the fissure “bathtub” back then https://www.youtube.com/watch?v=486We3TwnlE Hard to believe that 10 years has passed.
Today Bardarbunga appears to celebrate with small earthquake swarm. F.e. 7:45-8:00 eight quakes 0.1-1.2 Magnitude at different depths (1.1 to 20 km).
Well, that eruption was a little earlier than expected. After this one, we might have to wait until sometime in late December or early January 2025. Now, from what I’ve heard, before this eruption even occurred, the sill recieved more magma than usual from that bigger yet more disorganized magma system? If that is the case and does have some effect, the next eruption might be bigger than usual, but that is typical as these dormancy periods get longer, the eruptions get larger, maybe up to about 25-30 million cubic meters of lava stored.
On the subject of why it went north, it might be that the north is more brittle than the south, as the south has been repeatedly been intruded by dikes, making it more “elastic” than that of the cold and brittle north, which would’ve been previously cracked. As a mention from someone, “a dike follows the path of least resistance”.
So, another few months, potentially a larger eruption, here goes the long wait… (unless, if somehow, an eruption happens earlier than expected, which is less likely).
Activity at the left cone has increased tonight. Interesting flip-flopping behavior.
Bunch of very deep quakes just offshore south of Kilauea, 40 km deep. Probably the weight of the island stressing the crust but they do form a vertical stack so could be more significant. They might also be related to Kama’ehuakanaloa.
Kilauea tiltmeter is also going up faster again and it isnt raining this time. Onlyba week since that last little intrusion, I think theres a good chance it erupts. 🙂
Kama’ehuakanaloa is not the only Hawaiian volcanic structure south of Kilauea I remember reading.
The plume lifts up the crust, but the bulge is depressed by the island, and there are eruptions along that bent part. There are gigantic lava fields north of the islands, only mapped north of Oahu and Maui but the map had inferrence the field went further west. Theres another mapped area way south of the big island that is probably what you are thinking of. North and South Arch volcanic fields.
By the way, the age suggests they are still active. And they are lava flows that are erupted as floods in the deep ocean, thin sheet flows that erupted very fast
The biggest flows are probably 10x the size of Laki, and probably the closest thing in scale to a Traps formation eruption that can happen in the modern day although they seem to be infrequent.
There are some very old seamounts, but the next volcano along the Kea-Kilauea line is probably another 100K years off.
That’s ~10km deeper than Pahala quakes, could be the deep magmatic root that enters at 30km depth in the Pahala system.
Apart from this there are two clusters of 32km deep earthquakes: 1. half distance from Pahala to Kama’ehuakanaloa; 2. below SWRZ. Do they show deep upward stream of magma from the Pahala source towards both volcanoes?
New Zealand’s Geonet has an update on White Island:
Minor eruptive activity continues at Whakaari: volcanic ash emissions continue. Volcanic Alert Level remains at Level 3 and Aviation Colour Code remains at Orange (27 Aug)
Not especially noteworthy really, but I put it up because they’ve excelled themselves with another magnificent aerial photo!
Apparently a small river near Hekla has dried up and this has jappened before several eruptions, although doesnt seem to be a very reliable indicator. Still something worth watching, we might get to see how aseismic it really is or if we just werent listening very well.
Any idea of when this incident started? I saw a similar report in the Icelandic media a while back, so I am wondering whether this is a new event, this spring/summer, after the previous one came to nothing. (Apologies for vagueness over timing.)
Only saw it on the Iceland Geology group on facebook and with no official source to it, so I dont know when it happened.
OK, thanks.
Which river?
It’s not really an entire river, but some of the springs that form the source of a river. The springs are called Rangárbotnar and the river is Ytri-Rangá. They have a history of drying out a year or a few months before an eruption. Often the water returns just before the eruption starts.
The Catalogue describes typical precursory signs:
“Observed signals
For eruptions of Hekla volcano the only observed signals are earthquakes up to 90 minutes before eruption breaks out. Dwindling groundwater supply (drying up of small streams) has been reported some days or weeks before eruptions. Eruptions on the fissure swarm are preceded by earthquakes before or at the beginning of eruptions.”
https://icelandicvolcanos.is/?volcano=HEK
If the drying of creeks are a sign for a coming eruption, it must happen within days to weeks. If no eruptions happens within this time, it was a cheating sign.
We’ve had no earthquake swarms, so the extraordinary type of basaltic eruptions on the fissure swarm can excluded now (last one happened 1200 years ago).
Here is an essay about Hekla. Unfortunately it’s in Icelandic, but it translates quite well.
https://skemman.is/bitstream/1946/23065/1/Afl%C3%B6gunarm%C3%A6lingar%20vi%C3%B0%20Heklu%20RRK.pdf
Giggle translation of section 2.2.2
Changes in groundwater flow to the southwest (SW) and west (W) of the mountain could possibly been omens for Heklugos. There have been quite a few regular changes water level in streams and ponds around the last eruption. Close to two years before the eruption has the amount of water decreased in them and almost dried up. Sverrir Haraldsson farmer at Selsund, the husband and wife Ófeigur Ófeigsson and Halldóra Hauksdóttir farmers at Næfurholt have noticed these changes. According to Sverris, this happens in waves before an eruption, then the streams dry up, remain dry for a year or more, but then just before an eruption the flow returns. All these are streams that flow under Norðurhraun, which flowed from an eruption from Hekla in 1389. Hann has noticed these changes for the eruptions in 1947, 1970, 1980, 1991 and 2000. On August 15, 2015 he says that about two years ago these streams have dried up, but the surface has since been rising in the spring of 2015. According to Ófeigi and Halldóra, it has also noticed dryness in the streams that flow from Næfurholtshrauni, which flowed during the eruption last year 1845. They have not noticed a decrease in the streams that flow under the tuff. On the 15th August 2015, the surface of Selvatn was rising. The water is more involved than usual this time of year, but a year ago it was a small puddle, according to the couple. Selvatn is just right above Næfurholt, in the valley between Tindilfell and Bjólfell west (W) of Hekla.
Thanks very much for posting this. Very interesting. That little excerpt wonderfully illustrates why Iceland and its inhabitants make such a fascinating country.
The thesis was submitted in 2015 and the then most recent ebbing of the waters was 2013. The Selsund stream is clearly quite big for a stream/lækur, and looks like it’s spring fed, so its drying up would be clearly noticeable.
For anyone interested, the places named can be found on this bit of map: https://www.map.is/base/@458314,384963,z7.269999999999963,0. (And there’s a typo in the English abstract of the thesis: the candidate clearly muddled her NV and her SV, the latter, as in the excerpt, being correct.)
Hadn’t heard this. It is a known sign elsewhere, caused by inflation which leaves the ground water too low. It happens in the Philippines where it is taken as an indicator for an eruption within 6 months, and also seemed to have happened before the original Krakatau eruption. In this case, is the any insar indicator for inflation in the region?
I think the magma at Hekla could be too deep to reliably see with an interferogram, the maps in Hawaii never seem to react to deep magma movement only to stuff in the upper magma system. Or to the south flank moving, in Iceland the equivalent is the plates spreading apart.
At least, I have never seen an insar of Hekla, although I have seen one of Torfajokull. I dont know where to find them at the source.
The eruption in 2000 was about 0.1 km3, and after 9 years. The magma supply seems to be about 0.1 km3 a decade at the low end, it could be double that at the high end. So after about 2.5 decades is anywhere from 0.25 to 0.5 km3 if magma assuming constant flow. So its pretty unlikely to be a major VEI 4 or bigger but probably something somewhat larger than the most recent samples. This doesnt work so much if we get a basaltic eruption, those seem to have very wide variability in volume, from 10 million to over 1 km3.
One thing is certain that it will be very intense and fast. Even if it isnt 50 minutes nothing to full blast its quite likely to be fully ramped within a single day.
I have only seen interferograms covering a few days and that is a too short timeframe to show anything, unless it’s extremely fast. The inflation at Torfajökull or Askja doesn’t show up, but the one at Svartsengi does. We would really need to see data covering an entire year or more.
Here you can check Hekla’s GPS: http://brunnur.vedur.is/gps/hekla.html
Stations HESA (NE of Hekla) and SODU (S of Hekla) show in my eyes a positive trend, but I don’t know how to interpret it. SODU:
You find it if you exchange the comma before png with a point: http://brunnur.vedur.is/gps/eldfjoll/hekla/SODU-plate-year,png
Looks like it is going up and slightly west, not really noryh or south. But Hekla is at the plate boundary so that is likely the westwards motion.
Has moved up by about 2.5 cm since May it looks like. Not heaps but it is a recent trend too. Still not a confident guess this will result in anything significant but it is consistent with the idea of uplift stopping the springs feeding the river. The chance of eruption now is probably higher than before.
Hekla is like a bad witch volcano that likes to fool everyone. Maybe the signs are precursory signs, maybe Hekla wants to cheat us and does nothing … or waits until no one expects an eruption.
The Catalogue of Icelandic Volcanoes describes typical precursory signs of Hekla:
“Observed signals
For eruptions of Hekla volcano the only observed signals are earthquakes up to 90 minutes before eruption breaks out. Dwindling groundwater supply (drying up of small streams) has been reported some days or weeks before eruptions. Eruptions on the fissure swarm are preceded by earthquakes before or at the beginning of eruptions.”
Iceland: there’s some solid fountaining from the south cone, this morning!
The fountains have reduced to two: https://www.youtube.com/watch?v=Hia5Ejq2778
The right, bigger founain has a ~70° angle. It obviously shows a continuing high level of pressure in the magmatic system. The over months accumulated magma allow a stable eruptin for days. Very unlike the December to February eruptions.
How does it compare to the Fagradalsfjall eruptions?
Fagradalsfjall was smaller and more tourist friendly. The first eruption lasted very long, but had a dwarf rate of 12-13m³/s. Maybe the Fagradalsfjall eruptions were an extraordinary and accidental event, that usually isn’t “allowed” to happen during a Reykjanes Fires cycle.
Since Svartsengi has opened for intrusions and eruptions in November, Fagradalsfjall has kept silence. Maybe the geological door from the deep system towards Svartsengi was closed and forced magma to rise first at Fagradalsfjall. There was more pressure needed to create the November sill.
The fountains were, iirc, higher; clearly visible from Reykjavik (owing to location, not just height). Also, from a touristic point of view, the first two eruptions were in a natural amphitheatre, which was fantastic.
https://youtu.be/dWeao29ZVFw?si=X4YzwuWXUm7aBbPw
Very nice video from yesterday 🙂
The north vent in this seems to have evolved from a fissure to a single jetting vent to now what looks like a cluster of vents with no regular alignment. There are also a lot of cracks in the cone surrounding the vent area, I think maybe the single jet-like fountain was blocked off by the cone slumping into the vent, probably slow enough that it was built up by fresh spatter, until it was mostly blocked and had to erupt wherever it could. That could also explain why the south vent fountain has gotten a lot bigger, it has more pressure.
Bunch of quakes around 8 km deep under Fagradalsfjall. I wonder if it is a reaction to the ongoing eruption. The eruptions at Fagradalsfjall recently were all on a dike that started north of the mountain but if Svartsengi and Sundhnjukur are connected then perhaps an eruption directly up under the mountain is an option.
Its probably just stress from the eruption and rifting acting on the surroundings though.
After the quakes below Fagradalsfjall, quakes at Svartsengi followed. Maybe they show the magma flow. As long as the magma channels are open, magma will prefer to go to Svartsengi than to do something on Fagradalsfjall.
My non-scientific hunch would be stress.
I’ve been hibernating for a while, but has anyone written (or has anyone any thoughts) about the fact that the first seismic swarms and, I think, uplift, of this episode, back in ?2020 were at the west end of the peninsula. Didn’t Carl conjecture a possible eruption in the area of Sýrfell. Intriguing that the eruption leapt across to Fagradalsfjall. And then also that a possible early sign of this episode was in a system further east: the change in the water level at Kleifaravatn in the early 2000s.
There were earthquake swarms several years earlier in the Fagradalsfjall area, so an eruption there was not out of the question. See http://www.volcanocafe.org/unrest-at-fagradalsfjall/ . We don’t know exactly triggers the fires after 800 years of nothing, but build up of tectonic stress along the transform fault probably is related. The rifting event in 2020/2021 created the opening for the eruptions. They could have happened somewhere else along the fault zone but the weakness in both the Fagradalsfjall and Grindavik regions had already been created. Fagradalsfjall had in effect one eruption: the later two were small after effects from leftover magma.. The current eruptions are different and much more sustained: this may be closer to where the main conduit is. I would guess that this series will end in this region, and afterward there will a gap of years or decades before a new Reykjanes eruption elsewhere. But that is a guess.
Albert, I must say that I have enjoyed going down a VolcanoCafe rabbit hole regarding the current Reykjanes fires starting with Fagradalsfjall. In the lead up to the eruption, some really “crappy” comments were made to Carl for just mentioning the possibility of the start of a new 800 year cycle. It is even more incredible that it has all started in places that haven’t erupted in thousands of years. My previous volcanic perspective came from visits to Italy and Hawaii. This is like watching eruptions of Hualalai, or Campi Flegrei, or even Mauna Kea.
In haste: thank you. Interesting. Had missed that one. Will read and think about when I have a moment.
https://www-vedur-is.translate.goog/um-vi/frettir/jardhraeringar-grindavik?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-GB
New update: seems deflation is somewhat going down a similar path to the May eruption, so this might last as long as that one. Also, the field has expanded…
Also, hazard field has expanded a bit.
It’s difficult to judge accurately, but it looks to be around 1.6 km from Reykjanesbraut.
From Google Earth, probably closer to 2.7 km.
Makes sense why it wasnt advancing, it was mentioned it reached another fault scarp but it got blocked off, now it is past.
Inflation making a come-back?
There is the same trend in the last few samples for almost all stations, including at Grímsvötn and Askja, so I guess it’s probably just some bias in the measurements. Let’s wait and see what it does tomorrow.
Don’t all erupt at once! 😉
The eruptive rate doesn’t appear to have reduced, so that would suggest a sudden increase in supply rate if the inflation is genuine.
I think it is lower but it shows by the number of vents decreasing instead of the output at each vent decreasing. Its all going through one vent now so even if it has halved the single vent has probably not lost power. Will be interesting to see this time next week, the cone is massive and only 1 week old, it could be a complete structure with a lava geyser like in 2021, or just the way it is now with lower fountains.
The supply is high enough though that it can reach the ocean, if it lasts long enough.
IMO previously said that continued inflation from supply to tge sill couldn’t ve measured until the extrusion rate drops to 4 m3/s.
I think that it’ll be quite hard for the lava to reach the sea: much of the main road, Reykjanesbraut, is built several metres above the adjacent lava fields, so it’d have to overtop that before it gets to the sea. Obviously, much depends on the micro-contours of where the lava actaully flows but there’s a sizeable set of (flooded) depressions at Snorrastaðastjarnir that seem to be in its path.
But if it really “lasts long enough” anything is possible!
The greater danger probably lies with any possible future extension of the dyke.
I was trying to find a contour map last night, but I can’t remember the site I used to use in tge early days of Geldingadalur.
Lava in the swimming pool…
Witch’s hair sticky for swimmers in Reykjanesbær (RÚV, 28 Aug)
Icelanders do seem to get problems that the rest of us never have to cope with. Tough people!
Happens I’ve been researching Pele’s Hair hazards and rock-wool manufacture –Air-Blow stream of molten basalt like candy-floss– So was *very* interested by your report.
Thank you. !!
( Extra-solar planets need plate-tectonics’ subduction and a hydrological cycle to be silicic ? So, more likely to encounter basaltic lava pools and flows ?? )
Io certainly seems to be basaltic. Here’s an article from last week that I saw:
Comparing two proposed NASA missions to Jupiter’s moon Io (Phys.org, 23 Aug)
Sampling the erupting particulates from Io volcanoes on the fly would be seriously awesome. I hope that Elon’s increasingly cheap rockets will make one of these missions possible.
Venus has continebtal crst in some amount, but never developed tectonics on a global scale. Maybe it was on the cusp but its oceans were lost.
Mars has some silicic volcanism too I think, unless that has been disproven.
You may be thinking of the recently identified Noctis structure.
https://www.volcanocafe.org/mountain-of-the-night-the-lost-volcano/
Second Earthquake swarm on the day at Bardarbunga around 18:00
The swarm is at Greip. Bardabunga is to the west.
On the new map as well as in the animated gif from IMO the lava’s edge in the north looks like cut with a knife. Here is the reason why:
(Runnals, The Vogar Fissure Swarm, Reykjanes Peninsula, 2011)
The Institute of Earth writes about the recent Magma:
“The persistence of low K2O/TiO2 in basalts from May to August 2024 suggests that magma production and accumulation at depth has evolved towards a more steady-state, less dynamic system, which was a characteristic feature of basalts erupted during the medieval Reykjanes Peninsula Fires.”
https://earthice.hi.is/eruption-sundhnuksgigar-august-2024-preliminary-petrographic-and-geochemical-data
What does a “less dynamic system” mean for the future?
The K2O/TiO2 of 0.11-0.16 is the same as at the start of the eruption in Geldingadalir, and a lot lower than the lava erupted later in that eruption, or the subsequent eruptions at both Fagradalsfjall and Svartsengi up to the eruption in May, which had the same low K/Ti value that has persisted to present.
The way it looks to me the magma later in 2021 started getting generated deeper down and maybe interacted with the crust more too, for whatever reason that seems to have stopped. Maybe the pathway to the sill is mature and open so magma has little alteration.
Does this mean that magma there is a bit more primitive and less degassed than “normal” basaltic magma?
As fog/vog rules the area, “Live from Iceland” has published a thermal webcam that shows the eruption and lava flows behind a Highway:
https://www.youtube.com/watch?v=nQWvxRoxxE0
RUV’s Húsafell webcam shows visible lava fountains. From this perspective they look smaller than yesterday: https://www.youtube.com/watch?v=8bfcTBLvPiM
I dont know about more primitive than normal but probably more than it was up to the eruption in May or maybe later in the March eruption.
I think that starting in 2021 but not causing that eruption initially, was either a pulse of magma from deeper down, or that deeper magma had risen up and pooled somewhere in the source area earlier and was able to leave through the new intrusion. But the fact the eruptions at Svartsengi at least the first 3 times were the same magma, when it is pretty clear the rift and eruptions came from a different deep feeder system to Fagradalsfjall, does make it intriguing.
Maybe, the Svartsengi intrusions back to 2020 were involving this magma, and some of it was able to move over to Fagradalsfjall, or was drawn over by the intrusion that started there. The fact that between the 2021 and 2022 eruptions at Fagradalsfjall, there was uplift at Svartsengi, and the second two eruptiosn at Fagradalsfjall were slightly evolved high K/Ti magma too. it is interesting. It is also very interesting that now the same magma that started the intrusion at Fagradalsfjall in 2021 is now erupting at Svartsengi…
It is clear that these two are connected, but the fact the 2021 magma and subsequent, started up near keilir on the North America side, while the present sill crosses the fault and seems to have fractured starting from it, and the two locations are 15 km apart, maybe the whole peninsula is a lot more connected than was understood before this started. And the fact that all of the volcanoes from Eldey to Hengill are showing activity at depth is significant, they didnt all erupt close together last time, and were mostly orderly, not at all this time.
I think the high K2O/TiO2 magma could have been a local batch but the stuff starting 2021 and erupting right now is probably the primary composition and is related but not the same as the middle ages stuff. We will know for sure if one of the others erupts, but Krysuvik and Brennisteinsfjoll paired are like Svartsengi and Fagradalsfjall only 10x bigger… One of them erupting will be a huge event, probably at least as big as this eruption now and only going up. And an eruption at Hengill is bigger again, its last eruption was 1 km3 and a 20 km curtain of fire, but it skips most cycles.
Is there a difference between magma on oceanic divergent zones (f.e. MAR) and hot hotspots like Hawaii? On Reykjanes like along the MAR the vertical path from Moho to the eruption is short. This should make it possible that magma rises more primitve towards eruptions than on hotspot shield volcanoes.
I keep seeing veneral statements that there is a difference between mid ocean ridge basalt and plume basalt. But in Iceland it is very variable, Grimsvotn has 5% MgO and Bardarbunga has 8%, and they are neighbors, and Katla also has 5%, Askja is also 5%…
Reykjanes area has usually 7%, and is a ridge with less plume influence. But 2021 had as high as 11% and the lava in January was as low as 5%. So it is also very variable.
Hector would be a lot more knowledgable on the precise details.
Could that be reference to the fact that we are seeing the fissure eruptions occurring wider apart in time now, the last two in particular, instead of the 4 or 5 close together at the beginning, and the settling down of the magma explusion from the 3-5 km depths into some channels or fissures set up at the very beginning of the eruption series?
Interesting chart
from the IMO. They state ” The magma reservoir is believed to be emptying at a higher rate than filling up.” in their Aug-29 part of their long-going article.
Looks like a closely similar trajectory to the previous one, so far.
If that holds, the next one might be right around the start of December.
I’ll predict Christmas Eve. The last two were something like 75 and 90 days, so I’ll suggest 105 days.
Except my miscalculation of 105 days was wrong, so I’ll go with an increasing interval 😛
Since March the time between each start day of an eruption has grown by one month per eruption.
February to March 1 month
March to May 2 months
May to August 3 months
August to December 4 months
After a handful days the main eruption is usually over. It doesn’t matter if the volcano goes sleeping after five days or continues to erupt on low scale (as in April) for weeks. So we can/should count the months from the first day to next first day.
Nice little article in the New York Times about the renewed volcanism on the Reykjanes Peninsula:
https://www.nytimes.com/2024/08/30/science/iceland-volcano-eruption-lava.html
However, many of their pictures are from other areas on Iceland. Not sure why they didn’t use more of the footage from the Fagradalsfjall and Svartsengi eruptions.
Looks like Ljósufjöll’s had further earthquakes today in that same spot where it seems to be happening more frequently. I wonder if it’ll erupt in my lifetime.
I wish to add to your comment to consider also the recent earthquakes at Snaefellsnes https://en.vedur.is/earthquakes-and-volcanism/earthquakes/snaefellsnes/ as I think all of us are observing the actual true behavior of all volcanic systems in Iceland, our ignorance is preventing us from recognizing the cyclic repetition of volcanic events which has created Iceland itself and keeps replastering (if I can say this) with overlays of lava. Iceland is covered in km depths of lava flows from the past. What we see today is a microcosm of what goes on, in this Ice and Fire land.
I am aware that the IMO office has said that outgo of lava is still exceeding inflow. But I have to wonder
if what we are seeing here is that we’ve hit the bottom and inflation is about to take over.
Is there a risk of excess flourine emissions with the current eruption in Iceland?
The system is expected to be active for years if not decades, correct?
Apparently the high fluorine is only in some of the volcanoes. Reykjanes up to Langjokull isnt elevated, and neither is Bardarbunga. The volcanoes with elevated fluorine are all erupting evolved basalts, or andesite as at Hekla (with the highest elevation of F). Theres never been a comparison of F to MgO in magma because it is kind of two different fields but I think it is exactly a correation, F- is probably mostly in the form of HF, which has similar properties to water, and water gets concentrated in evolving magma.
Hawaii is very low in F-, and very high in SO2, it is probably the least evolved basalt of any major volcano. But that is only the summit, Kilaueas ERZ sometimes erupts evolved magma and if that has highly elevated F- then this theory could be solid. I dont know if Mauna Loa is this way, its rift eruptions dont behave like they are locally sourced, rather being long dikes from the summit, like a way bigger version of the sill and rift at Svartsengi.
Begs the question of ‘Where the F’ it comes from.
UK’s Bluejohn seems due to mineralised water circulation, which also concentrated lead ores.
Must surmise there may be a biogenic influence, an uncommon extremophile merrily processing available chemicals…
Maybe for some sources but the source in Iceland is the magma, as is all fluoride eventually. Even though it is a halogen fluorine has a lot of chemical similarity to oxygen more than chlorine, CaF2 is insoluble while CaCl2 will absorb water from the air to dissolve itself. HCl is a very strong acid that attacks metals vigorously but isnt chemically toxic while HF is a weak acid that reacts in weird ways with most things and is a fast acting poison if it gets in blood. It actually really doesnt dissolve flesh like usually assumed, but precipitstes a neurotransmitter from the blood, very nice… 🙂
Apparently the F- ion is so negatively charged it can behave like an OH- ion and bind strongly to metals and oxide minerals. That, and it forms a very stable bond to silicon, something the other halogens cant do at all in the presence of oxygen. This is probably because it is a first row element, a lot of those have bizarre properties compared to their successors below, and often have relation to the element adjacent in the row below.
I was kind of hoping there would be more talk about the titular element, it is a crazy substance. Solid F2 is explosively hypergolic with liquid hydrogen, and burns it at over 4000 C at atmospheric pressure. That is, the reaction has such a small activation energy it is spontaneously explosive below 20 K, which is almost unbelievable.
F2 was also considered to add to liquid O2 for rockets to make it hypergolic with the fuel without much extra risk of using just F2 but then the exhaust would have HF as a component. But it was experimented with extensively, rockets run on F2 and diborane, F2 with lithium borohydride, lithium metal and F2, ClF3 and hydrazine… Also, most crazy of all, mixing F2 and liquid ozone, and also using mercury as a fuel at one point too…
The Germans were especially inventive when it came to exothermic mixes of exotic chemicals. Lots of weird and wonderful (and exceedingly dangerous) concoctions.
List of Stoffs (wiki)
I had to do a semester of German during my chemistry degree since so much of chemistry was written in that language in those days.
The book Ignition is worth reading, most of the fluorine chemistry is from its potential in rocket propellant. I think a lot of people are also aware of ClF3 but it isnt the worst option, as any compound with hydrogen can theoretkcally be made into a fluorine analogue… HOF is a thing, where F is in a partial negative state not a full -1, and OF2 is also a thing. XeF6 and KrF2 are also things… KrF2 actually has an even higher redox potential than F2 because it is an endothermic compound. Theoretically OF3+ is a thing but nothing is able to chemically take 4 electrons from an oxygen atom, it would spontaneously decompose to F2 and probably back to O2. Apparently O3F is also s thing, ozone with a fluorine stuck on. And FO2F has been isolated, the fluorine analogue of hydrogen peroxide. It makes F2 look harmless, explosive oxidation of elemental Cl2 is not trivial… But nearly all research on it is over 60 years old so I dont know how true a lot of all these things really are.
As a side, dissolving K2MnF6 in HF in the presence of SbF5 evolves elemental F2 spontaneously at room temperature. K2MnF6 is made by dissolving KMnO4 in HF with H2O2.
My colleague blew up a graduate chemist once.
He left her to do an experiment purifying silver nitrate electrolyte to remove copper and lead impurities. So they did the logical: tried sodium hydroxide, lime etc…and ammonia.
Bad move!
The 5 L beaker full of electrolyte and black precipitate exploded. Kaboom! I rushed from my office out to the lab – fortunately she was miraculously uninjured despite glass and black sludge everywhere, except for a terrible attack of the giggles.
I’m fairly sure what they accidentally produced was silver nitride. When I went to clean it up the next day the now dry black powder on the walls and floor was exploding under the wash cloth I was using. Interesting experience.
She’s now a very senior scientist with a large company, and he’s recently retired. So both survived…
When I was a graduate student we nearly burned down our whole department when a bottle of t-butyllithium caught fire. That’s another very excitable compound. Fortunately the local fire service knew about us and sent 19 fire trucks, and were able to save the building. Which was good since I’d left my lab books at my work bench…
We do not know where it comes from in Iceland! It may be the upper mantle or the lower crust. Fluorine travels easily dissolved, so it may show up away from the original source.
Are Grimsvotn eruptions typically fluorine-rich?
If not, that alongside the lack of a large enough caldera suggests that the Skaftar fires did not come from Grimsvotn after all. With all the fluorine in Myrdarsjokull the logical suspect might then be Katla … unless another Vatnajokull volcano does do elevated fluorine (Thordarhyrna?)
I am not sure that is known. Remember that Grimsvotn’s own eruption do not produce much lava, just tephra. I have not seen reports of fluorine measurements for it. Holuhraun would be interesting, since we know where its magma came from
Albert, considering that fluorine is so chemically reactive, and wants to instantly bond to any molecule it is near, how do we get the element itself so mobile in the magma? HF is really bad stuff.
Grimsvotn and Laki have the same magma, Laki is a little bit more MgO but neither are that high, below 6% compared to standard tholeiite basalt that is 6-10%. Laki and Grimsvotn erupt lava that is similar to the stuff erupted by that tiny vent next to Grindavik in January, or the early evolved stuff at the start of Kilaueas 2018 eruption.
It was often said on here back then that Grimsvotn was pure plume basalt but it definitely isnt getting to the surface in that pure form, its an open system but ut isnt a durect hole into the mantle like Kilauea, or like Bardarbunga and Reykjanes seem to be.
It does also kind of conclusively kill the idea that Laki was directly erupting vertically from the mantle, it does share a same crustal storage as Grimsvotn somewhere maybe not the central volcano itself though. The same is true of Katla with Eldgja, which again show the same chemistry but with Eldgja slightly more mafic.
Regarding fluorine too the majority if sources of high F- volcanoes are in subduction zones, and in the presence of continental crust. Iceland is an exception but it is not unlikely that Iceland isnt entirely oceanic crust and has continental fragments buried in it. As a general trend the places F- shows up in volcanoes is where there is felsic crust so it probably comes from there us my guess, or HF is fractioned out of evolving magma, again very similar to water.
Lot of fluoride in some Greenland magmas too. Perhaps it’s a mantle source.
Randall only neutral F2 is highly reactive, F- is happy to be anywhere as long as it has its electron. Its like chlorine as Cl2 is a poison and very reactive but chlorine in salt is harmless and its absense will kill you…
It is well known that hydrofluoric acid can dissolve glass but that is aqueous HF, anhydrous HF doesnt dissolve glass by itself and its reaction with SiO2 is reversible. SiF4 and H2SiF6, are also volatile. F- forms only one bond so cant polymerize itself, where O2- can. So it can only stay in minerals by sticking to a free spot on something else.
Thank you for your thoughts !!
Is explanation for F content that this is *not* first time Atlantic’s been open.??
So, possibility of subduction slab’s fluid circulation effects lingering, akin to Snake River / Yellowstone region, the Farallon Plate’s legacy beneath US ??
IIRC, Iceland’s ‘Hot Spot’ has been back-traced via SE Greenland, up to High Arctic.. Beyond, track seems lost to subduction at North Pacific / Aleutian Arc, all evidence lost…
Wildly tangential, is that curiously offset Paektu Mountain / Baekdu Mountain volcano on Chinese / Nork border F-rich ?
Here is two fun animations of the solar photospheres flow behaviour in 3D and first one that I seen to perhaps try to visualise that. Despite its being gas plasma the convective cells only rise so far up before spreading out, it does seem that the lower solar atmosphere have a tropopause like Earth? it does legit since temperatures rise when you go above the solar photosphere preventing plasma convection to rise higher up
https://m.youtube.com/watch?v=V59RETVJVe0&pp=ygUNc29sYXIgZ3JhbnVsZQ%3D%3D
https://m.youtube.com/watch?v=X_ozy4ZXlvY
Its also remakable how bright the photosphere is despite its very very thin density of gas plasma, the gas ”air” density at bottom of the photosphere is only 1/100 th of earths surface pressure and at the top of the solar granules its maybe 1/5000 th of earths air at surface level, yet the plasma storms glows as bright like welding arc, and the solar plasma quickly increase in density below that so you are still looking at lots of photon matter through your field of view from an observer above so not strange its so bright. Earths polar lights also give off light at lower densities than the solar photosphere.
At the bottom of the slice of convection zone of the solar medium pressure woud be as dense as venus surface atmosphere pressure
Looks like the eruption is quickly dying down, unless the fountains have just drowned themselves in a lava pond. It will be interesting to see how far the lava managed to flow given it was visible in the Vogastapi cam forground overnight.
Its concerning though how powerful this eruption was, if this is the new norm then Grindavik is unlikely to survive another eruption like the one in May or January. it is also concerning that up to May all of the dikes had only rifted the central part of the rift close to the origin, but this eruption went all the way up north to the northern end of the November dike. if it does the same thing and same distance but going the other direction then an eruption within Grindavik or in the ocean will happen. I actually never thought it would erupt up this far north at all let alone so strongly for so long, there is nothing even slightly comparable in terms of cone size in the whole Holocene in this part of Reykjanes.
To be honest, although this eruption was quite harmless and photogenic it sets a very scary precedent for the next time.
On Húsafell webcam it looks like a dying Strombolian eruption: https://www.youtube.com/watch?v=8bfcTBLvPiM
If it ends today, the eruption will be much shorter than the May-June eruption. The previous one lasted around 3 weeks. The current one probably 1-2 weeks.
The May-June eruption had this size: “Lava field has an area of 9.3 km² and a volume of approximately 45 million m³”
How is the current eruption compared to this? If I’m right, I once have read that the area is 15 km², so larger than the May eruption. Lava has covered nearly the whole northern pre-historical lava field.
New post is up! Tallis gets into deep water
https://www.volcanocafe.org/volcanic-tsunamis-an-analysis/