The Hell Machine

Guest post by Chad

The three musketeers, firing away

As is now abundantly clear, a new eruptive cycle on the Reykjanes Peninsula has begun. While an isolated eruption did happen in the ocean off the end of the peninsula in 1783, there has not been an eruption on land since 1240, today 781 years ago.

The eruption ongoing now has ratherbroken the regular cycle of eruptions at Reykjanes. Normally those begin at Brennisteinsfjoll and go west over a few hundred years, but this vent is on Fagradalsfjall, a mountain right in the middle of the peninsula. This area would not be expected to activate for at least a century yet, but here we are, watching the camera religiously as this new volcano grows before our eyes.

The magma is being generated at a great depth, nearly 20 km or twice as deep as normal eruptions in this area begin, and by mantle that is nearly totally melted to result in a lava that has a very high concentration of olivine. This sort of basalt even has its own name, picrite, and it is the closest thing to the ancient komatiite lava that erupts on the Earth today. This has been interpreted as a possible case for a shield volcano to form at, something which has not happened here for many millennia, but I think there are rather more profound implications for this. The magma is fluid and extremely hot, well over 1200 C, and that is enough to allow both physical and thermal erosion of the interior of the conduit, which will serve to only allow more magma to flow, in a compounding effect. Direct mantle eruptions are rare, but one that is currently ongoing if hard to observe is going on under the ocean near the island of Mayotte near Madagascar. It is not particularly intense, but since it began in mid 2018 some 5 km3 of lava has erupted to date.

The magma for eruptions like this is created by decompression melting as the pressure drops, a self feeding cycle that is limited only by the rate of mantle flow to the area. It is a self sustaining machine, the Hell Machine as I like to call it.

Hell Machines are a rare sort of eruption. Like said above they are perhaps best categorised as some sort of hybrid between a shield volcano and a lava flood fissure eruption. The eruption rates may be sustained at a relatively high rate for a long time, well above the rate seen in the formation of shield volcanoes but also never getting to the colossal rates seen in the big fissure eruptions, at least not for any long duration.

Mayotte is an example of a Hell Machine that is erupting now, it is in the deep sea and it may be that most such eruptions are, but there is a historical eruption like this that occurred on land and it offers some tantalising clues.

On the 1st September 1730 an eruption began on the island of Lanzarote, in the Canary Islands. It was relatively large, creating a cinder cone that was ultimately named Caldera del Cuervos, as well as over a few months the similarly sized Caldera del St Catalina and Pico Partido cones. This constitutes what would have been a typical if somewhat larger than average eruption in the Canary Islands, but we now know this first eruption managed to set off the Hell Machine. Eruptions continued into the next year, though it had declined from the initial high rates as expected, the flows were still fed at an impressive volume to sustain over a year. Submarine eruptions well off the west coast and going up all the way to just inland beginning in June of 1731 marked the completion of the hell machine, it was now in full working order, and eruptions marched eastwards back onto land to flood even more of the island. Observations after this are poor as few inhabitants stayed beyond this point but the eruptions continued into 1736, erupting some 5 km3 of lava, constituting the large majority of the volume of all eruptions in the Canary islands in recorded history. Lanzarote has no active central volcano, and has not possessed one for millions of years, the eruption of 1730-1736, or Montanas del Fuego as it is known locally, was fed out of the mantle directly by extensive melting under the base of the crust. Perhaps most notably, all the eruptions from the late Pleistocene and Holocene on Lanzarote before this were on the northern part of the island, the area where the Montanas del Fuego eruption occurred had not been volcanically active for possibly several tens of thousands of years or more, a certain similarity it does share with Fagradalsfjall.

Lava fields on Lanzarote. Source: Becerril et al. ,Assessing qualitative long-Term volcanic hazards at Lanzarote Island (Canary Islands), 2017 Natural Hazards and Earth System Sciences, 17, 1145-1157

The Signs

The first sign of a hell machine is that the eruption is persistent and erupts out of the mantle directly, something clearly the case already. An eruption should also be a rifting event, where the rift is kept open by new magma, and this also seems to be happening, as a dike has formed within the crust going from less than 2 km depth down to at least 7 km, with possibly many feeding points below this that are not resolved. The very high temperature of the lava will also serve to enlarge the pathways, something that may take longer than a week to become evident but which is expected.

So far our eruption is quite small, even tiny, but it has a big future. The first obvious sign could be that the vent increases in output, or that it stays constant but another vent opens. We may already be seeing this, as the vents are rather a lot larger than they were to begin with, and the output appears to have increased. Deflation is not observed along the dike either, which would suggest the eruption is being fed by continued decompression melting in the mantle, a process that may increase accordingly with the eruption rate and set the hell machine in motion.

What will become of the Reykjanes peninsula if this occurs? Perhaps the most direct consequence is that land within perhaps 10 km of Fagradalsfjall is potentially at risk. There is no danger to Reykjavik but Grindavik may suffer if not from the lava then from the gas emission. The effect it will have on the normal Reykjanes cycle is also unknown, most typically the section of the transform fault at Brennisteinsfjoll is the first to go but this time around the section going through Krysuvik was set of by the recent intrusion, leaving Brennisteinsfjoll in a precarious situation. Decompression melting at Krysuvik may well have already begun now in preparation to its awakening, and Brennisteinsfjoll could wake up rapidly following its eventual quake. Eruptions here will resemble those from the Reykjanes Fires, but taking a back seat to the lava flood that is just beginning now at Fagradalsfjall. We are watching history creating itself.

Perhaps this will not come to fruition, it may turn into a shield instead, or even stop. But with all the signs it is looking like the future is grand for the new little volcano.

Chad – 2021

866 thoughts on “The Hell Machine

  1. Is there an article regarding the pinatubo eruption? I couldn’t find in with the search option.

    • I have seen that. Pompeii was is at a similar distance to Vesuvius as Kingstown is to Soufrey. Yes Vesuvius’ ash cloud was likely to be about twice as big as Soufrey’s. Enough velocity could be devastating.

      My prayers are with SVG at the moment.

  2. Ash has been confirmed to have landed in Grenada. Grenada is the island state most immediately south of St. Vincent and the Grenadines #LaSoufriere


    St Vincent’s #LaSoufrierevolcano has created 3 volcanic ‘hot towers’ in the last 5 hours on the GOES 16 IR. Enormous columns of latent heat are regularly punching into the stratosphere. If #LaSoufriere continues at this pulse surge, it’s likely to be rated at least a level 5 VEI.

  4. Diario de Avisos are saying SO2 may reach the Canary Islands.

    ”a erupción del volcán La Soufriere en el Mar Caribe ha provocado que sus nubes de SO2 recorran el océano Atlántico “a toda velocidad”
    🔴🔴 The eruption of La Soufiere volcano in the Caribbean Sea has caused its SO2 clouds to travel the Atlantic Ocean ′′ at full speed ′′

    • How high is that Luis? Is it as high as the 4th eruption at 40kft?
      It appears to have gotten progressively stronger.

      • I think this one is the strongest untill now… don’t know how big.

        • They are stronger, 3 of them passed the -80 C column in the IR legend for the IR photograph, yesterday I only saw to -77 C, but today’s seem to be approaching -90 C.

          Also the gravity waves effect upon the lower clouds like a ripple in the pond from a stone, reached all the way to Dominica.

      • Up to 52.000 feet / 16 km. Dunno if it was still in progress at that point.

        Volcanic ash plume from La Soufrière on the island of St. Vincent reaching heights ~52,000 ft (~16 km) well SE of our region.

        Nube de ceniza volcánica de La Soufrière en la isla de San Vicente alcanzando alturas de 52,000 pies bien al SE de la región.

  5. Volcano watching is often a painful and sad occupation. As Peter Bray said earlier. May God have mercy on the Islanders.
    I am always in awe of the power beneath our feet and how fragile life is in comparison. What never ceases to impress is the wonder of regeneration. The Islanders who left will return. Those who remained will rebuild. The vegetation will recover.

    • Yes, its one thing to admire the power of nature, but so often that power has dreadful consequences and I fear this is one.

  6. Reports are via @NEMOSVG is that scientists have stated that the series of events following the 1st eruptive explosion of 9 April 2021 is reminiscent of the 1902 eruption. The 1902 eruption continued for a period of 10 months. #LaSoufriere #lasoufriereeruption2021

  7. ?w=600&h=441

    The latest ash plume has now reached Barbados without fully coming off St Vincent…#LaSoufriere

  8. Magma is on the move at Katla, Taal is restless again, major eruption in St Vincent, Grimsvotn on the brink, so much is stuff is happening that I can’t figure out what my article should be about!

  9. Biggest eruption of the 21st century? Grímsvötn 2011 is the biggest I think.
    Looks to me that we are seeing a big one.
    Notable sunsets in Western Europe and some global cooling perhaps.
    Those poor Islanders are going to need big help.

    • 2011–2012 Puyehue-Cordón Caulle is considered the biggest of the 21st century, so far.

      • It comes with age, forgetfulness… I was commenting on this blog during Puyehue-Cordón Caulle, I forgotten how big it was already! I think the atmosphere of Grímsvötn 2011burnt an image on me. Lol’s

    • In terms of volume the largest eruption is in Mayotte, a submarine effusive eruption, >5 km3.

      Cordon Caulle is the biggest in VEI.

    • After watching this great video i would like to know, of there is any new data about the flowrate of these 4 vents combined??
      It must be over 10 m3/s, according to this video….

      • There have been no flyovers or measurments this weekend due to weather, I think they are going to do some flights tomorrow.

        • Or if not due to weather (as the video above shows great visibility) then for other reasons, bottom line, no measurments/flyovers during this weekend.

        • One of the articles on mbl mentioned yesterday that IMO would not have anyone on site this weekend unless something major happened

  10. Here are 2 timelapses from yesterday afternoon to this morning

    From the Geldingadalir camera:

    From the Meradalir camera:

    They are a bit slow and moody. The Geldingadalir flow was actually already so fast that speeding up would be a shame (though I have to admit, quite spectacular, it just over in the blink of eye then)

    Enjoy and share your insights (that’s not my turf 😉 )

  11. Looking through twitter, reports of pyroclastic flows on the eastern side of island, reaching the sea.

  12. Live Update from Barbados coming up shortly

    UWISeismic Research
    A press conference will be held today at 2:30pm AST with Prime Minister of Barbados Mia Mottley, Home Affairs Minister Wilfred Abrahams and Director of The UWI Seismic Research Centre, Dr Erouscilla Joseph.
    It can be viewed using the link below.
    La Soufrière Emergency Update (Barbados)

  13. 19:40:30 ish on the Geldingadalir RUV camera. Collapse and then expels lots of lava

    Update on the vast SO₂ cloud produced by the #LaSoufrière #eruption. #Sentinel5P #Tropomi data on April 11 show the SO₂ cloud reaching #CaboVerde in the eastern #Atlantic. SO₂ altitude ranges from the upper-troposphere to lower-stratosphere; total SO₂ mass ~0.45-0.6 Tg.

    • That is not half bad. For one single coughing dragon. I gather 10 months with boom-boom-chakkalakkalakka-BOOM would be something to watch out for.

      The Windy 3-day-forward SO2-prognosis seems to be based on current erupted material, so I expect that to change as this continues.

  15. Looks like the ISS is going to come reasonably close to be overhead St. Vincent around sunset(in about two hours), who knows, we might get some great photos from there.

    • I wonder if the bright material are pyroclastic flow deposits. If so, then they are minor, and it doesn’t look like any village has been destroyed. Good news it seems. Although there are some random houses here and there that may not have been so lucky.

    • If these both are related to climatic (Stratospheric) SO2 injections (Tg) it is worth noting that Pinatubo ejected 14 to 23 Tg SO2 over the course of apx. 4 days if memory serves me correct.

      Meaning La Soufrière needs to go on at this rate for ~62 to ~76 days to “fill those shoes”. (14/0,225 vs 23/0,3) Am I thinking straight here given asumptions?

  16. White steam clouds coming from La Soufriere now, perhaps the collapse has started to fill with water?

      • Groundwater from the rain. La Soufriere had a crater lake in the past so that the new collapse probably stands below the water table and may fill with a lake at some point, may or may not be happening already.

  17. Likely gonna be a LOT of transatlantic flights affected between Europe and the Lesser Antilles and South America Same goes for flights to/from the US/Canada, especially Miami.

    • I like the way the first one stops and take a look onto the volcanic vents..staring for 2 secs as wild life toward wild nature…

  18. a lot of lava flux all over the place….officials maybe hurding ppl away…what will be tonight?

  19. I went to post about Dr Eva Eibl and her rotational sensor technology which was detecting crustal changes while the 3rd vent was opening up, but suddenly my browser was slammed and the DNS blocked the post. Her instrument was setup about 7 km away from the new vent and she has a twitter post showing the readings.

    Can anyone else do a twitter search and see if they can locate this important tweet?

    – Randall

  20. Okay, had to leave the duck duck browser and drop back to the google search engine to re-find this important tweet

    Dr Eibl tweets

    The third fissure opened around midnight on 7 April at #Geldingadalir #Reykjanes. My rotational sensor (installed by @isor_iceland) at 7 km distance from the eruptive site detected some change a few hours before and is sensitive to volcanic tremor.

    I am attempting to contact her to learn more about this sensor technology

    – Randall

    • this is the stuff she look for…I dont get much, I’am not a geo related connoisseur but seismic fall in study ring a bell for me..

  21. Question, do we see the restoration of the 2nd vent in the original Geldingdalur cones? Remember that the 2nd vent was covered over, but it now seems like there are two gas emission vents based upon the lava bubbles emitting in the large pool of the north cone. See

    It appears that gaseous emissions are coming from two locations in the lava pool now.

  22. Did anyone else notice the light in the sky coming in at 21:25:20 in this cam?

    • At the 3:50 – 4:15 mark, it looks like the #2 fissure’s forming a nice little shield!

  23. Would be great if the Geldingadalir cam was turned a bit, would be sweet to see this lavafield from the other side.

    • If they turn it we’ll miss the twins…I already said that ruv1 cam should be duplicated or more..that’s the most important pov of the event so far.

      • Could turn it for five minutes each hour, and then back to the twins. The camera has been stationary all day as far as I can tell.

        • yeah…panning..tha’s manual sport…and meanwhile you could miss some kodak moments…if I were the it tech I simlply install 2 samsung cam onto ruv1 cam spot..replace the others for lava spreading controll and voila!..eventually some pan and so media cover up, and not only…scientf, marketing whatever…anyway is a safe spot, I dont think that will be lava terorist atacked

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