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This eruption is definitely a little wierd. Thank you Bruce for your graphs, makes the action a little easier to understand. Thank you Amanda-Jo and Shawn for the updates.
As a physicist, I’d say there’s a mechanical reason for the flip flopping of the vents, like a temporary solid magma flap that’s being pushed to one side or the other by the varying gas pressure, thereby diverting the magma flow left or right. It will disappear when the physical conditions inside the vents change.
Thank you for brining us up to date on the eruption. Bruce G's charts graphically describe the eruption series and how they are alike and different. Good stuff there! Interesting pulsing of the two vents. Impressed that the Icelandic road crews are already re-establishing the roads.
Thank you so much for displaying the vent switching. After hearing about it on Isak's stream today I really wanted a chance to see some of it, and now I have the timestamps too. Neat stuff.
Thanks for the update Shawn. The northern vent outflow is at a slightly higher elevation than the southern vent, I wondered if it was a siphoning kind of action between the two.
Isaak's most recent video (Day 12) is interesting where he goes below the peak of the berm - showing that the lava field is actually slightly higher than the berm but the connectivity and motion seemingly stops it from spilling. However the berm will have to go even higher to stop future westerly flows flooding into what is now the Blue Lagoon Valley.
Thanks for the update. Another thing that's interesting on the plots at about 11:00 - Uplift flattened out just before the eruption started. Maybe lava moving toward the vent?
Very well pointed out at 14:41 where you were talking about the vents erupting in the same crater, that faces away from Vogar out from two different vents. I asked myself often, why does the activity changes so often, that lava spills over the right or over the leften side of the cone ? Now, I have the answer. But it looks amazing, how the mount has build up since last nov, 20th., that I can see every day with my own eyes from at home.
Really interesting and a bit exciting (had never seen/heard of such things as well). I found it on the Sandholl cam 2,5 days ago. It was clearly visible how the right cone restarted several minutes past 4 am, no activity there in the hours before visible (for me😀, maybe I overlooked sth.?) in the stream. But it was much more surprising that the cones started to alternate, more or less often, more or less long and how this went on and on. RUV wasn't interested, yesterday was polling day in Iceland and today they had to analyse.😀And Shawn Willsey wasn't here either.🙁😀So tyvm for your update!
Glad to hear you had good family time Shawn. I’ve been away over the weekend so only catching up now! The oscillating vents (the first time I’m aware of this phenomenon) and various theories are fascinating and I’m looking forward to hearing more in this regard. Great to have Bruce’s data - a good visual aid. Thanks Shawn, Amanda-Jo et al.
It sure seems like the south/right vent of that linked cone is outgassing substantially more than the north/left vent. I noticed that when the north/left is erupting, the south/right is just outgassing. When the effusion switches, the south/right vent produces lava gas. The north/left vent just goes totally quiet. So an explanation for this cyclic phenomenon ought to include the fact that during all phases, the outgassing seems to have a preferential path to the surface on the south/right vent.
My theory on the oscillation is that the two vents are in a Y-shape. As vent #1 is effusing, vent #2 cools off, causing the gas pressure to slowly increase in that cooled tube until it finally forces its way to erupt. The magma now has a preferential and higher velocity path through vent #2 causing the flow in vent #1 to decrease and now vent #1 starts to cool, building up gas pressure until it cycles again.
Hey Shawn, welcome back :) Thanks for this informative update, it's much appreciated as always! Many thanks also to Bruce and to Amanda Jo! As for the "pulsating" vents, well I’d say it’s related to gas pressure + some kind of obstruction... but I’m no expert! ;) Would definitely love to hear Mike Poland’s take on this. Also, there are some interesting guesses in the comments below. Looking forward to your Random Roadcuts from Arizona! ;) Btw there's still a bit of a weird echo to your audio...
Thanks Professor, at 21.00 there is a 3rd vent north of the twin vents spraying lava. All 3 vents are in line over the rift, so it appears. Fluid flow thru a narrow channel has some dynamic reversals because of erosion and replacement of hydraulic materials and solids. Think of how a stream of water over almost flat sand will slowly snake back and forth. Perhaps this occurs with lava and gas voids in the rift.
about 2 hours ago I did an evening remote drone flight booked through NatureEye but deliberately didn't check how things were developing today. I had assumed it would just be a single cinder cone building up so was very confused when at one point I thought there was a second vent but on moving the drone round for a better view, it had disappeared.
Thank you Shawn this is fascinating. my interpretation in the difference between this eruption and the previous eruptions is this. The beginning eruptions each have fractured and expanded the magma conduits to an increasing extent. They now exist in a state where the buoyancy of the magma is able to keep the entire system expanded and open. It would not surprise me to see the GPS uplift flatten out with the current rate of effusion remaining more or less constant. i see the subsurface now being something like a mixture of icecubes and chopped ice. A kind of solid that gassy liquids easily push through and can change over relatively short time frames. Shawn, you Nick Zentner and GeologyHub have given me my new favorite pass time of Armchair Geologist !:-) ps i must give an honorable mention of Gyfli of Just Icelandic 🙏💜⚡
16:00 My guess is the feeding pipe comes up and splits in two like a Y, one of the upper parts goes to that left side and the other to the right. The lava splashes up for a while in one side of the cone and the splashed lava heats up the sides of the cone in that area weakening it until a chunk slides off the inside into the cone and plugs that pipe. So then the other side gets fed until it does the same thing. By that time that first chunk has been in the lava long enough to soften it so it breaks through that (that's the weaker of the two pluging the pipes). Maybe this is seldom seen because you usually have just one feeding pipe to the cone, so any chunk blocking the pipe gets pushed aside from pressure
Thank you for this update Shawn. I also was watching the eruption last night and noticed the off gassing from the more southern vent, but I also wonder if there are lava tubes extending further as there are smaller rising in the lava. This has been an interesting year for me learning about the Icelandic volcano systems and geology in general. Thank you for you work and presentations on youtube.
What you describe about the South and North vents makes me think of piston like action or something opening and closing. Maybe there are two gas vents where there isn’t enough pressure to allow both vents to spew at the same time but as one side empties, there is just enough slowing to cause allow a “soft clot” of magma to form and allow gas to build up and later push through the new, loosely formed obstruction. 🤷♀️Just trying to imagine something I know absolutely nothing about. Thank you.
Thanks, Shawn, and thanks to Bruce for his graphs. ?Do you think that there was such little earthquake activity leading up to this event because there is now an open conduit, and that magma didn't have to break a lot of rock to erupt?
That oscillating suggests to me that there's a chunk of rock, possibly from a wall collapse, that has got into the vent. Mostly, this is blocking the secondary tube and is held there by the pressure, but if the pressure drops temporarily, the rock falls free and rolls over to block the primary conduit. When the pressure resumes, it now holds the rock in the primary conduit. On the next pressure drop, the rock rolls back over to the secondary tube and the cycle starts again. I had been musing about whether wall collapses were contributory factors in ending an eruption. My idea is that as the eruption proceeds, there is an accumulation of solid rock debris in the crater from the wall collapses. When there's sufficient pressure in the system, the rocks get blown clear of the vent, and the flow continues. As the pressure starts to wane, the rocks are no longer blown clear and settle around the vent, restricting the flow. This is not enough to stop the eruption, but it slows it down enough that the pool within the cone cools. The higher viscosity lava in the pool then further restricts the flow, reducing the pool temperature still more. Eventually the vent becomes blocked by a combination of rocks and increasingly viscous lava. I would be interested to see if we get a sustained eruption where there is a constant prevailing wind, preventing the build-up of a cone. My suspicion is that the flow will continue longer, because any collapse from the leeward wall would not be trapped within a cone, and would flow out, keeping the vent clear. What prompted me to think this was observing that all of the eruptions seem to be pretty constant until a spatter cone develops. Even once that happens, they seem to maintain their activity. It's only once the cones get large enough that they start collapsing back into the pool that we start to see a decline in the output. It would be nice to see a lab experiment using hot wax in a heated header tank, flowing into a tube which enters the bottom of a funnel. The overflowing wax can be returned to the header to maintain the pressure. This should be able to maintain the flow indefinitely. Gradually adding stones or glass beads into the funnel should restrict the flow enough to cause the wax in the funnel to cool and become thicker, eventually blocking off the flow. The stones/beads should not be so heavy that they instantly sink and block the funnel, but have a density just slightly higher than that of the molten wax.
Supposing a similar picture to the one at 20:00; If the lower elevation vent might be 'clogging up' at low flow pressures (due to a longer/narrower conduit etc) we might see switching with flow pulsations Also, outgassing could affect it too - perhaps the most direct gas route is at the higher elevation vent, which means it takes over flow when buoyancy builds up enough but doesn't flow until then.
I think the oscillation started sometime between Thursday night and Friday morning local time. During Friday it had longer intervals a little reminiscent of the 2021 eruption.
I love the mystery of the oscillation. If it is blockage, why does it not melt away being in the heat of the lava for hours? And gases, I started thinking about if gases are caught in hollows, fills up and then pushes something… I mean, why am I even imagining these things. Im an art historian!😂😂😂 I hope you can find some good answers to the oscillation before I start imagining a giant troll messing about in there! Thanks for the update!
Shawn - I think you should consider the plumbing and reservoir set up such that magma “sloshing” from one side to the other causes the pulsing you are seeing.
Looks like gas pressure drops in the active vent , while gas pressure in other vents increases to activate. Perhaps there is a bend in the feed to the near surface that temporarily blocks one vent than the other to create a valve-like action.
It is obvious that pressure changes are causing the oscillating events. It might be that one side's pressure pinches off the other vent. You can see small bursts make it through, when the opposite side is active, which indicate pressure throttling.
20:36 Perhaps with the switching spatter cone the lava has so me other below earth gas vent that at times blows massive amounts of gas and other times it doesn't . the one time it blows it forces the lava to exit from one cone, the time it does not do it. the lava goes straight up without diversion.
I threw in a late comment yesterday, on the previous YT post, speculating that it was a grooved rotating plug at a Y junction point, that would have the groove to the left side and then to the right. Too much time in my past looking at IV stopcocks in the OR, I guess. It seems as if the flow of the northern side is more energetic, so perhaps there is a cyclic pressure shift down below where at higher pressure it pushes a plug up to block the south vent conduit, but then as pressure subsides the plug drops to then favor a flow to the south by blocking thr north side conduit.
I have two thoughts on the oscillation. One could be a blockage or wall of malleable material shifting back and forth like a septum in your nose. this could be driven by gas build up. I would look to see if the outflow is more violent after it oscillates. I don't think would be parallel I think there is interaction between the two vents causing it. It to be consistent oscillation I don't think it is likely to occur from to independent processes happening in parallel.
Thank you for the update and the data. In the GPS data you concentrate on the uplift since this is the biggest of the three directions of change. The vertical drop of the latest eruption is about 220 mm. The horizontal Svartsengi data show consistent movements to the North and to the East during the vertical rise with a reversal of 60 mm southward and 30 mm westward after the start of the eruption. From this it seems that the Svartsengi measurement point is East of the dike that feeds the eruption. The vector addition of these three is 230 mm, consistent with a much bigger bulge diameter than the length of the dike opening. Is there any analysis of theGPS data to determine the three-dimensional shape adjustment of the bulge in the course of the sequence of eruptions?
Could you have a blockage working like a valve in an air rachet. Similar to those found with geysers that causes the predictable pulses but in this case a directional shift.
My wife and I really enjoy your broadcasts! Thanks for doing what you do! I'm curious if it's some kind of weird "P" trap type situation with the vents? Your diagram reminded me of the piping sinks/toilets, etc. Have an awesome day!
Is it possible the oscillation could be due to some kind of vacuum or suction effect? Sort of like an assassin's teapot? Where an inflow of atmosphere is becoming intermittently blocked and creating a suction effect that prevents lava from flowing out of the primary vent, but not out of the less preferred secondary... until that suction effect goes away again and the primary vent once again becomes active
Maybe the switching is change in lave chemistry that affects density. one side has less friction and more dense lava goes to lest friction side. Or the change may be temperature related, hotter gas maks more liquid lava then cooler gas makes denser causing switching vent location.
Maybe the storage area only holds what volume that accumulated before the August eruption? That area has reached its elastic maximum? Will be interesting to see before the next one…if inflation resumes.
I wonder if the tube connecting the 2 vents has a length and size that just happens to be a resonating frequency for the pressurized gasses as the lava refills kind of like blowing over the mouth of a bottle... in this case an upside down bottle.
Hey... I'm thinking the change in vents could be due to accumulation of lava, partially closing one at a time till pressure blows it apart? Could also depend on gasses tho
Bruce's graphs seem to indicate that over time the conduits have cleared any obstructions that caused back pressure on the chamber subsurface. This allows full flow without the need to break rock in the 'build up" phase of the quakes and less need for rise and fall in the GPS data. A clear, relatively unobstructed conduit over time seems reasonable as it seeks equilibrium of pressure. The volcano has cleared it's throat and opened a large enough conduit to avoid the need to build high pressure in the chamber below. Just a guess but seems logical. If this is true, the GPS data, both rise and fall, should become less extreme with each eruption and the quakes should drop off to where it only needs to clear the openings (cooler end plugs) each time. As to the oscillations, again it seems pressure related so likely an obstruction near the end of the pathway that is fluttering. Something down there is obstruction one path at a time and shifting with the currents. Over a period it should melt away and give equal and open access to both paths. Again using logic not data to "guess" but an "educated guess" because pressure of any type act similar. I have seen similar obstructions in pressurized water lines where something foreign gets into the system and gets stuck at a wye of reduced size and flutters around to obstruct one path or the other but not both. Pressurized system always seek equilibrium over time. I have also heard of similar events in hydraulic lines on heavy equipment when a foreign object or debris gets into the fluid system beyond the system filter, usually during a repair where the mechanic was not careful enough to avoid contamination entering the system.
Renting of the rift zone between the plates, have any measurements be made of the separation of the plates in iceland? Similar to the African Rift zone, Hawaii is a volcano over a hot spot, so Iceland is over a hot spot or the moving of the plates causing the eruptions. Thanks for the update
After watching the oscillating vents, and seeing you're diagram Shaun, could there possibly be a shallow sill connected to both vents?. Slowly filling up, then releasing, and taking all pressure from first vent to second vent with it. Second vent seemed to have a lot more output when it did erupt, from my perspective anyway, could be completely wrong though
could it be a divided chamber where the two vents are either side of a dividing wall with a common feed under the dividing wall which causes each chamber to build pressure independent of the other
If the inflow of magma equals the outflow of lava, would it be correct to state that barring an earthquake that would break the pipe, this eruption could last a very long time? Or is the current inflow of magma not sustainable/abnormally high and is expected to go back down and end eruption any time?
The most fascinating thing in nature is its chaotic behaviour. Imagine dripping water from a tap. You know that drops will appear after some time. The more time passed, the more likely a drop will appear. But it is quite uncertain when exactly a drop will appear. I think the eruptions so far followed a similar quasi periodical but chaotic pattern, too. We expected that, after we discovered some regular stuff (for example, the uplifting before the 3rd eruption was higher than before the 2nd one), ... that this pattern will continue. But this time, it didn't. We discovered that there's a significant earthquake pattern before an eruption. But this time, it was different. We don't know the reason for this different behaviour, and we don't know if the next eruption will follow this pattern now or switch back to the old pattern. That's the fascinating chaotic behaviour of natural systems. For the oscillating vents, I have my own explanation. Of course, I don't know if I'm right. The lava conduit from deeper layers splits into two somewhere in the subsurface. At first, both vents were fed by the conduit with a similar amount of magma. But both don't have exactly the same shape. So the magma at one point may prefer vent A because degassing may be easier at vent A. Then, because there's no degassing at vent B anymore, the magma in this vent may sink down to where the conduit splits. Parts of the magma in vent B are now forced by the gasses to move into vent A too. This increases the volume of magma in vent A but decreases the amount of magma in vent B. At one point, the gases switch to vent B because of less magma resistance. Then vent B is erupting, and vent A is calming down. The magma in vent A now sinks down like the other did before, and at some point, the gasses again prefer to feed vent A again. This also may show some chaotic behaviour. I'm no geologist, so I'm not sure if this is a possible way how two vents erupt in a quasi oscillating manner. But for me, it's a nice explanation until an expert says that this is impossible. 😉 Thank you again for another very interesting video. Have a nice day 👋🏻👴🏼
Are the active vents coming up through an earlier flow? and could some of that material be unstable and prone to collapse? Could the switch between vents be caused by collapses in the "tube" feeding the primary vent, temporarily blocking it, so the magma diverts to the second vent, until the blockage material in the primary vent remelts and is cleared? Maybe the pulses in magma flow could trigger those collapses. I'm no volcanologist, but I have seen odd behaviour with bentonite breakouts occurring during HDD drilling through unstable sediments. Bentonite under pressure in some ways seems to act like magma and finds its way to the surface.
So, I think your picture of the vent-switching may be misleading. Because I'm wondering if it's more like a larger channel forking into 2 narrower ones, with the actual fork being shaped like the profile of a knife. Because _I think_ that shape creates a situation where the "choice" of which direction to flow, which channel to take, has barely any difference, which would allow for easy switching between the two. I'm also gonna go out on a limb and posit that fluid-dynamics-turbulence at or just past the fork is what causes temporary "blockage", thereby causing the flow to temporarily prefer one vent, then the other. But it's been well over 27 years since my last fluid-dynamics class 😉, and I never learned much of anything about turbulent flow. Someone who studies fluid-physics might know of an analogous device that causes water to "pulsate" by flipping between two different flow-paths.
curiosity question. Lately there have been a pretty decent amount of large scale solar storms theory being that it can affect on earths enviornment. of course like the moon affecting the push and pull of the oceans word of mouth is that large enough solar storms can cause earthquakes and earthquakes themselves alongside the tectonic movement can cause an eruption to to changes in the lava pockets and changes in lava tunnels opening up or creating a large enough tunnel for a lot of lava to break through of course all pockets being connect to the core you can read as blood vessels being clogged up is there any way of knowing wether the solar storms lately are causing this ?
I'm curious I'm wondering if one vent is gassing off till the lava gets too heavy on one side Then starts coming out the gas side and the restriction of the lava starts putting gas out the other tube just a thought
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This eruption is definitely a little wierd. Thank you Bruce for your graphs, makes the action a little easier to understand. Thank you Amanda-Jo and Shawn for the updates.
Volcano are very artistic and individualistic.
It’s their sense of humor: they laugh when we try to find patterns.
@@edwardlulofs444 😂
Thanks!
As a physicist, I’d say there’s a mechanical reason for the flip flopping of the vents, like a temporary solid magma flap that’s being pushed to one side or the other by the varying gas pressure, thereby diverting the magma flow left or right. It will disappear when the physical conditions inside the vents change.
Agreed
Fascinating!
Sluffiing off, collapsing walls over the vent?
Can’t they drop cheap and disposable pressure sensors from drones? Would be fascinating data ❤
like a septum in your nose?
Thank you for brining us up to date on the eruption. Bruce G's charts graphically describe the eruption series and how they are alike and different. Good stuff there! Interesting pulsing of the two vents. Impressed that the Icelandic road crews are already re-establishing the roads.
Thank you so much for displaying the vent switching. After hearing about it on Isak's stream today I really wanted a chance to see some of it, and now I have the timestamps too. Neat stuff.
Thanks
Hi Shawn. Welcome back. I'm glad to know you had family time, and you sound fresvh and rested. Thanks as always for your insight. 🧙🏽♂️
Welcome back and thank you for the update! Thanks also to Bruce G. for his clear and informative charts!
Great to have you back, Shawn.
Thank you!
Thank you for another interesting update. The oscillating vents are so fascinating.
Thanks for the update Shawn. The northern vent outflow is at a slightly higher elevation than the southern vent, I wondered if it was a siphoning kind of action between the two.
Please don’t feel you need to apologize for being on vacation! We appreciate you keeping us updated but not when it would interfere with family!
Exactly. Family time during a holiday is a lot more important than updating us! We should’ve been spending more time with our families, too, anyway!
Isaak's most recent video (Day 12) is interesting where he goes below the peak of the berm - showing that the lava field is actually slightly higher than the berm but the connectivity and motion seemingly stops it from spilling.
However the berm will have to go even higher to stop future westerly flows flooding into what is now the Blue Lagoon Valley.
Good Afternoon from Oak Island (OKI), NC. Thank you for the update Shawn!
Thanks for the update. Another thing that's interesting on the plots at about 11:00 - Uplift flattened out just before the eruption started. Maybe lava moving toward the vent?
Very well pointed out at 14:41 where you were talking about the vents erupting in the same crater, that faces away from Vogar out from two different vents. I asked myself often, why does the activity changes so often, that lava spills over the right or over the leften side of the cone ? Now, I have the answer. But it looks amazing, how the mount has build up since last nov, 20th., that I can see every day with my own eyes from at home.
Thank you Shawn, for keeping us informed. I like your episodes very much. Also big thanks for your time!!!
Thanks for all the hard work on these videos!
Thank you Bruce. Very nice to see that data in chart form.
Really interesting and a bit exciting (had never seen/heard of such things as well). I found it on the Sandholl cam 2,5 days ago. It was clearly visible how the right cone restarted several minutes past 4 am, no activity there in the hours before visible (for me😀, maybe I overlooked sth.?) in the stream. But it was much more surprising that the cones started to alternate, more or less often, more or less long and how this went on and on. RUV wasn't interested, yesterday was polling day in Iceland and today they had to analyse.😀And Shawn Willsey wasn't here either.🙁😀So tyvm for your update!
Thank you for the update!
Excellent as always Prof W!! Hope you had a good mini break.
Thanks Professor Willsey.
Glad to hear you had good family time Shawn. I’ve been away over the weekend so only catching up now! The oscillating vents (the first time I’m aware of this phenomenon) and various theories are fascinating and I’m looking forward to hearing more in this regard. Great to have Bruce’s data - a good visual aid. Thanks Shawn, Amanda-Jo et al.
Aloha from Makaha.......oscillating vents, fascinating subject....I saw that on Isak's video yesterday...
Thanks to Shawn and Amanda Jo for the update and news. That oscillating vent activity is particularly fascinating!
Thank you Shawn. Always clear and interesting information.
Love logging on to an update thank you 😊
Thank you for the detailed update, Shawn. We all appreciate your videos and diligent work ethic! Inspiring man!
Thank you Prof Willsey 🙏 ❤
It sure seems like the south/right vent of that linked cone is outgassing substantially more than the north/left vent. I noticed that when the north/left is erupting, the south/right is just outgassing. When the effusion switches, the south/right vent produces lava gas. The north/left vent just goes totally quiet. So an explanation for this cyclic phenomenon ought to include the fact that during all phases, the outgassing seems to have a preferential path to the surface on the south/right vent.
My theory on the oscillation is that the two vents are in a Y-shape. As vent #1 is effusing, vent #2 cools off, causing the gas pressure to slowly increase in that cooled tube until it finally forces its way to erupt. The magma now has a preferential and higher velocity path through vent #2 causing the flow in vent #1 to decrease and now vent #1 starts to cool, building up gas pressure until it cycles again.
Like your hypothesis better than some others here. 👍🏼 👌.
Hey Shawn, welcome back :) Thanks for this informative update, it's much appreciated as always! Many thanks also to Bruce and to Amanda Jo!
As for the "pulsating" vents, well I’d say it’s related to gas pressure + some kind of obstruction... but I’m no expert! ;) Would definitely love to hear Mike Poland’s take on this. Also, there are some interesting guesses in the comments below.
Looking forward to your Random Roadcuts from Arizona! ;)
Btw there's still a bit of a weird echo to your audio...
Thanks Professor, at 21.00 there is a 3rd vent north of the twin vents spraying lava. All 3 vents are in line over the rift, so it appears. Fluid flow thru a narrow channel has some dynamic reversals because of erosion and replacement of hydraulic materials and solids. Think of how a stream of water over almost flat sand will slowly snake back and forth. Perhaps this occurs with lava and gas voids in the rift.
about 2 hours ago I did an evening remote drone flight booked through NatureEye but deliberately didn't check how things were developing today. I had assumed it would just be a single cinder cone building up so was very confused when at one point I thought there was a second vent but on moving the drone round for a better view, it had disappeared.
Thanks for a detailed description...I can say it's been my hobby for last 10 yrs to keep track of volcanic activity around the globe!
I love these updates- always learning! Ty Shawn & tribe
Thank you Shawn this is fascinating. my interpretation in the difference between this eruption and the previous eruptions is this. The beginning eruptions each have fractured and expanded the magma conduits to an increasing extent. They now exist in a state where the buoyancy of the magma is able to keep the entire system expanded and open. It would not surprise me to see the GPS uplift flatten out with the current rate of effusion remaining more or less constant.
i see the subsurface now being something like a mixture of icecubes and chopped ice. A kind of solid that gassy liquids easily push through and can change over relatively short time frames.
Shawn, you Nick Zentner and GeologyHub have given me my new favorite pass time of Armchair Geologist !:-)
ps i must give an honorable mention of Gyfli of Just Icelandic 🙏💜⚡
Thank you for the update
16:00 My guess is the feeding pipe comes up and splits in two like a Y, one of the upper parts goes to that left side and the other to the right. The lava splashes up for a while in one side of the cone and the splashed lava heats up the sides of the cone in that area weakening it until a chunk slides off the inside into the cone and plugs that pipe. So then the other side gets fed until it does the same thing. By that time that first chunk has been in the lava long enough to soften it so it breaks through that (that's the weaker of the two pluging the pipes). Maybe this is seldom seen because you usually have just one feeding pipe to the cone, so any chunk blocking the pipe gets pushed aside from pressure
Thank you for this update Shawn. I also was watching the eruption last night and noticed the off gassing from the more southern vent, but I also wonder if there are lava tubes extending further as there are smaller rising in the lava. This has been an interesting year for me learning about the Icelandic volcano systems and geology in general. Thank you for you work and presentations on youtube.
@Shawn Willsey Thank you so much for all your videos. X
Thank you Professor
Thanks Amanda Jo
Good morning from Santa Monica CA 🌴 thank you for the update
What you describe about the South and North vents makes me think of piston like action or something opening and closing. Maybe there are two gas vents where there isn’t enough pressure to allow both vents to spew at the same time but as one side empties, there is just enough slowing to cause allow a “soft clot” of magma to form and allow gas to build up and later push through the new, loosely formed obstruction.
🤷♀️Just trying to imagine something I know absolutely nothing about. Thank you.
Thanks, Shawn, and thanks to Bruce for his graphs.
?Do you think that there was such little earthquake activity leading up to this event because there is now an open conduit, and that magma didn't have to break a lot of rock to erupt?
That oscillating suggests to me that there's a chunk of rock, possibly from a wall collapse, that has got into the vent. Mostly, this is blocking the secondary tube and is held there by the pressure, but if the pressure drops temporarily, the rock falls free and rolls over to block the primary conduit. When the pressure resumes, it now holds the rock in the primary conduit. On the next pressure drop, the rock rolls back over to the secondary tube and the cycle starts again.
I had been musing about whether wall collapses were contributory factors in ending an eruption. My idea is that as the eruption proceeds, there is an accumulation of solid rock debris in the crater from the wall collapses. When there's sufficient pressure in the system, the rocks get blown clear of the vent, and the flow continues. As the pressure starts to wane, the rocks are no longer blown clear and settle around the vent, restricting the flow. This is not enough to stop the eruption, but it slows it down enough that the pool within the cone cools. The higher viscosity lava in the pool then further restricts the flow, reducing the pool temperature still more. Eventually the vent becomes blocked by a combination of rocks and increasingly viscous lava.
I would be interested to see if we get a sustained eruption where there is a constant prevailing wind, preventing the build-up of a cone. My suspicion is that the flow will continue longer, because any collapse from the leeward wall would not be trapped within a cone, and would flow out, keeping the vent clear. What prompted me to think this was observing that all of the eruptions seem to be pretty constant until a spatter cone develops. Even once that happens, they seem to maintain their activity. It's only once the cones get large enough that they start collapsing back into the pool that we start to see a decline in the output.
It would be nice to see a lab experiment using hot wax in a heated header tank, flowing into a tube which enters the bottom of a funnel. The overflowing wax can be returned to the header to maintain the pressure. This should be able to maintain the flow indefinitely. Gradually adding stones or glass beads into the funnel should restrict the flow enough to cause the wax in the funnel to cool and become thicker, eventually blocking off the flow. The stones/beads should not be so heavy that they instantly sink and block the funnel, but have a density just slightly higher than that of the molten wax.
Hi Shawn and all from Westchester county , NY
Supposing a similar picture to the one at 20:00;
If the lower elevation vent might be 'clogging up' at low flow pressures (due to a longer/narrower conduit etc) we might see switching with flow pulsations
Also, outgassing could affect it too - perhaps the most direct gas route is at the higher elevation vent, which means it takes over flow when buoyancy builds up enough but doesn't flow until then.
I think the oscillation started sometime between Thursday night and Friday morning local time. During Friday it had longer intervals a little reminiscent of the 2021 eruption.
I love the mystery of the oscillation. If it is blockage, why does it not melt away being in the heat of the lava for hours? And gases, I started thinking about if gases are caught in hollows, fills up and then pushes something… I mean, why am I even imagining these things. Im an art historian!😂😂😂 I hope you can find some good answers to the oscillation before I start imagining a giant troll messing about in there! Thanks for the update!
Shawn - I think you should consider the plumbing and reservoir set up such that magma “sloshing” from one side to the other causes the pulsing you are seeing.
Thank you for your insight and information!!
Looks like gas pressure drops in the active vent , while gas pressure in other vents increases to activate. Perhaps there is a bend in the feed to the near surface that temporarily blocks one vent than the other to create a valve-like action.
Thank you professor. So interesting, the vents alternating makes me think a lot. Hope you find an answer. Greetings from the Yucatan peninsula 🇲🇽
Thank you great update enjoy your information 😊
Great update!
It is obvious that pressure changes are causing the oscillating events. It might be that one side's pressure pinches off the other vent. You can see small bursts make it through, when the opposite side is active, which indicate pressure throttling.
20:36 Perhaps with the switching spatter cone the lava has so me other below earth gas vent that at times blows massive amounts of gas and other times it doesn't . the one time it blows it forces the lava to exit from one cone, the time it does not do it. the lava goes straight up without diversion.
At 21:10 you can see lava coming out the backside of the vent as well on the right side, so maybe a hole in the cone on that wall as well.
Hmmm always different eruption but the same magma… thank you Shawn
Much appreciated !!
I threw in a late comment yesterday, on the previous YT post, speculating that it was a grooved rotating plug at a Y junction point, that would have the groove to the left side and then to the right. Too much time in my past looking at IV stopcocks in the OR, I guess. It seems as if the flow of the northern side is more energetic, so perhaps there is a cyclic pressure shift down below where at higher pressure it pushes a plug up to block the south vent conduit, but then as pressure subsides the plug drops to then favor a flow to the south by blocking thr north side conduit.
Another great update. Thanks!
Question- How is the volume of magma estimated?
I have two thoughts on the oscillation.
One could be a blockage or wall of malleable material shifting back and forth like a septum in your nose. this could be driven by gas build up. I would look to see if the outflow is more violent after it oscillates.
I don't think would be parallel I think there is interaction between the two vents causing it. It to be consistent oscillation I don't think it is likely to occur from to independent processes happening in parallel.
I wonder if variability in the gas content or lava temperature and the unique layout of the fissure throat could explain that behavior.
Thank you for the update and the data. In the GPS data you concentrate on the uplift since this is the biggest of the three directions of change. The vertical drop of the latest eruption is about 220 mm. The horizontal Svartsengi data show consistent movements to the North and to the East during the vertical rise with a reversal of 60 mm southward and 30 mm westward after the start of the eruption. From this it seems that the Svartsengi measurement point is East of the dike that feeds the eruption. The vector addition of these three is 230 mm, consistent with a much bigger bulge diameter than the length of the dike opening. Is there any analysis of theGPS data to determine the three-dimensional shape adjustment of the bulge in the course of the sequence of eruptions?
Could you have a blockage working like a valve in an air rachet. Similar to those found with geysers that causes the predictable pulses but in this case a directional shift.
So those two vents have a bistable fluidic oscillator in the feed branch . 😊
My wife and I really enjoy your broadcasts! Thanks for doing what you do! I'm curious if it's some kind of weird "P" trap type situation with the vents? Your diagram reminded me of the piping sinks/toilets, etc. Have an awesome day!
Is it possible the oscillation could be due to some kind of vacuum or suction effect? Sort of like an assassin's teapot? Where an inflow of atmosphere is becoming intermittently blocked and creating a suction effect that prevents lava from flowing out of the primary vent, but not out of the less preferred secondary... until that suction effect goes away again and the primary vent once again becomes active
Maybe the switching is change in lave chemistry that affects density. one side has less friction and more dense lava goes to lest friction side. Or the change may be temperature related, hotter gas maks more liquid lava then cooler gas makes denser causing switching vent location.
What about connecting barrells with the high one have a lower out stream,?
Maybe the storage area only holds what volume that accumulated before the August eruption? That area has reached its elastic maximum? Will be interesting to see before the next one…if inflation resumes.
I wonder if the tube connecting the 2 vents has a length and size that just happens to be a resonating frequency for the pressurized gasses as the lava refills kind of like blowing over the mouth of a bottle... in this case an upside down bottle.
Mr brain hurts, ‘oscillating’ vents😮 all adding to my knowledge base & that’s really cool 👍
you can see it better in Isak's drone flight yesterday, one vent filling and then emptying while the the other vents fills up again....
fascinating and interesting
Hey... I'm thinking the change in vents could be due to accumulation of lava, partially closing one at a time till pressure blows it apart? Could also depend on gasses tho
Bruce's graphs seem to indicate that over time the conduits have cleared any obstructions that caused back pressure on the chamber subsurface. This allows full flow without the need to break rock in the 'build up" phase of the quakes and less need for rise and fall in the GPS data. A clear, relatively unobstructed conduit over time seems reasonable as it seeks equilibrium of pressure. The volcano has cleared it's throat and opened a large enough conduit to avoid the need to build high pressure in the chamber below. Just a guess but seems logical. If this is true, the GPS data, both rise and fall, should become less extreme with each eruption and the quakes should drop off to where it only needs to clear the openings (cooler end plugs) each time.
As to the oscillations, again it seems pressure related so likely an obstruction near the end of the pathway that is fluttering. Something down there is obstruction one path at a time and shifting with the currents. Over a period it should melt away and give equal and open access to both paths. Again using logic not data to "guess" but an "educated guess" because pressure of any type act similar. I have seen similar obstructions in pressurized water lines where something foreign gets into the system and gets stuck at a wye of reduced size and flutters around to obstruct one path or the other but not both. Pressurized system always seek equilibrium over time. I have also heard of similar events in hydraulic lines on heavy equipment when a foreign object or debris gets into the fluid system beyond the system filter, usually during a repair where the mechanic was not careful enough to avoid contamination entering the system.
Renting of the rift zone between the plates, have any measurements be made of the separation of the plates in iceland? Similar to the African Rift zone, Hawaii is a volcano over a hot spot, so Iceland is over a hot spot or the moving of the plates causing the eruptions. Thanks for the update
Just amazing 😯🤩👌
After watching the oscillating vents, and seeing you're diagram Shaun, could there possibly be a shallow sill connected to both vents?. Slowly filling up, then releasing, and taking all pressure from first vent to second vent with it. Second vent seemed to have a lot more output when it did erupt, from my perspective anyway, could be completely wrong though
Do the GPS data anomalies coincide with the geomagnetic storms?
could it be a divided chamber where the two vents are either side of a dividing wall with a common feed under the dividing wall which causes each chamber to build pressure independent of the other
If the inflow of magma equals the outflow of lava, would it be correct to state that barring an earthquake that would break the pipe, this eruption could last a very long time? Or is the current inflow of magma not sustainable/abnormally high and is expected to go back down and end eruption any time?
Thanks Shawn, I would love to know why there is two.
Di…Cumbria.
The most fascinating thing in nature is its chaotic behaviour. Imagine dripping water from a tap. You know that drops will appear after some time. The more time passed, the more likely a drop will appear. But it is quite uncertain when exactly a drop will appear.
I think the eruptions so far followed a similar quasi periodical but chaotic pattern, too. We expected that, after we discovered some regular stuff (for example, the uplifting before the 3rd eruption was higher than before the 2nd one), ... that this pattern will continue. But this time, it didn't. We discovered that there's a significant earthquake pattern before an eruption. But this time, it was different. We don't know the reason for this different behaviour, and we don't know if the next eruption will follow this pattern now or switch back to the old pattern. That's the fascinating chaotic behaviour of natural systems.
For the oscillating vents, I have my own explanation. Of course, I don't know if I'm right. The lava conduit from deeper layers splits into two somewhere in the subsurface. At first, both vents were fed by the conduit with a similar amount of magma. But both don't have exactly the same shape. So the magma at one point may prefer vent A because degassing may be easier at vent A. Then, because there's no degassing at vent B anymore, the magma in this vent may sink down to where the conduit splits. Parts of the magma in vent B are now forced by the gasses to move into vent A too. This increases the volume of magma in vent A but decreases the amount of magma in vent B. At one point, the gases switch to vent B because of less magma resistance. Then vent B is erupting, and vent A is calming down. The magma in vent A now sinks down like the other did before, and at some point, the gasses again prefer to feed vent A again. This also may show some chaotic behaviour.
I'm no geologist, so I'm not sure if this is a possible way how two vents erupt in a quasi oscillating manner. But for me, it's a nice explanation until an expert says that this is impossible. 😉
Thank you again for another very interesting video.
Have a nice day 👋🏻👴🏼
i remeber seeing the pulsing before in iceland, can not remember when but i think more than 2 jears ago, was mutch more spectacular.
Maybe the stronger gas allows the main event flow but when the gas is not as strong the crust blocks the flow and causes it to go to the other vent
Are the active vents coming up through an earlier flow? and could some of that material be unstable and prone to collapse?
Could the switch between vents be caused by collapses in the "tube" feeding the primary vent, temporarily blocking it, so the magma diverts to the second vent, until the blockage material in the primary vent remelts and is cleared? Maybe the pulses in magma flow could trigger those collapses.
I'm no volcanologist, but I have seen odd behaviour with bentonite breakouts occurring during HDD drilling through unstable sediments. Bentonite under pressure in some ways seems to act like magma and finds its way to the surface.
So, I think your picture of the vent-switching may be misleading. Because I'm wondering if it's more like a larger channel forking into 2 narrower ones, with the actual fork being shaped like the profile of a knife. Because _I think_ that shape creates a situation where the "choice" of which direction to flow, which channel to take, has barely any difference, which would allow for easy switching between the two. I'm also gonna go out on a limb and posit that fluid-dynamics-turbulence at or just past the fork is what causes temporary "blockage", thereby causing the flow to temporarily prefer one vent, then the other.
But it's been well over 27 years since my last fluid-dynamics class 😉, and I never learned much of anything about turbulent flow. Someone who studies fluid-physics might know of an analogous device that causes water to "pulsate" by flipping between two different flow-paths.
Perhaps there are collapses beneath the surface that cause the pulsing.
Awsome some great views
Save some action for spring When I’m there
curiosity question.
Lately there have been a pretty decent amount of large scale solar storms theory being that it can affect on earths enviornment.
of course like the moon affecting the push and pull of the oceans word of mouth is that large enough solar storms can cause earthquakes
and earthquakes themselves alongside the tectonic movement can cause an eruption to to changes in the lava pockets and changes in lava tunnels opening up or creating
a large enough tunnel for a lot of lava to break through of course all pockets being connect to the core you can read as blood vessels being clogged up is there any way of knowing wether the solar storms lately are causing this ?
I'm curious I'm wondering if one vent is gassing off till the lava gets too heavy on one side Then starts coming out the gas side and the restriction of the lava starts putting gas out the other tube just a thought