Category: Magma

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Ongoing earthquake activity in Katla volcano (Week 50)

Yesterday and today there has been some earthquake activity in Katla volcano. While this earthquake activity is less then what have been taking place during the past few months this activity is bit higher then it used to be during the winter times. The largest earthquakes so far have had the magnitude around ML2.0 (from what I can tell). Currently this earthquake activity is limited to three areas inside Katla volcano caldera according to report from Iceland Meteorological Office.


Earthquakes in Katla volcano during the past 48 hours. The ares with most earthquake activity can clearly be seen inside Katla volcano caldera. Copyright of this picture belongs to Iceland Meteorological Office.

This earthquake activity is more then compared to the winters few years back. Here is an comparison from the years 2009 and 2010 in Week 50 (current Week).


Earthquake activity in Katla volcano during Week 50 in the year 2009. Copyright of this picture belongs to Iceland Meteorological Office.


Earthquake activity in Katla volcano during Week 50 in the year 2010. Copyright of this picture belongs to Iceland Meteorological Office.

As can be seen with this comparison, the earthquake activity now in Katla volcano is considerable higher then in what is called an normal year in terms of activity in Katla volcano. What this means is unclear. But this suggests an eruption is not far away in Katla volcano. But when and how big is impossible to know at current time. Many of the earthquake swarms in Katla volcano are due to dike intrusions taking place in the Katla volcano caldera. But not all of them get to the surface to start an eruption. However such activity can and has increased hydro-thermal activity inside Katla volcano caldera. As has been evident during the past few months in Katla volcano caldera.

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Harmonic tremor continues to drop in El Hierro volcano

It seems that currently the eruption in El Hierro volcano is coming to an end. I do not know if this is an permanent end to the current eruption or just an short break in it. The reports that I have seen so far suggest that the main crater out of the coast of La Restinga has stopped erupting. The current harmonic tremor however suggests that an eruption is still taking place somewhere. But I have no idea where that might be at current time, and so far no clues where that might be. But the lack of earthquakes north of El Hierro Island suggests that an eruption might be taking place there. But that is just speculation.


The harmonic tremor in El Hierro volcano at 20:36 UTC. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

Other then this. There is not that much to report from the eruption in El Hierro volcano, or what is left of it at current time. If there are any major changes. I am going to report them soon as I can. But at current time. It does not look like there is isn’t a lot needed to be reported on the eruption in El Hierro volcano.

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Earthquake activity continues in Katla volcano

Even if it is December and Mýrdalsjökull glacier has added around 6 meters of snow on top of it self. It seems that the earthquake activity in Katla volcano is rather strong, even if it winter already in Iceland.


Earthquake activity in Katla volcano past 48 hours. Some of this earthquakes might be frost-quakes due the freezing weather in Iceland for the past few days. Copyright of this picture belongs to Iceland Met Office.

The earthquake activity in Katla volcano is resistant in the Katla volcano caldera and has been that for several weeks already. I cannot interpreted this earthquake activity other then Katla volcano is preparing for an eruption. But when I am not sure at this moment. There is an pattern of earthquakes in Katla volcano caldera, this pattern has been in place since Week 27, but that is the week when the minor eruption took place in Katla volcano caldera last summer (summer 2011).

It is clear that this earthquake activity in Katla volcano is going to continue. I am assuming that this earthquake activity is going to continue until a eruption takes place in Katla volcano. But there is also the chance of the year 1999 event. When a small eruption took also place and earthquake activity remained high for several weeks after that. But after some time the earthquake activity started to drop. For the moment I find that to be unlikely outcome given how long the earthquake activity has remained high in Katla volcano after the minor eruption this summer.

Donations: I am going to try and setup the geophones in Eyrarbakki village and the geophone close to Katla volcano in December. But that trip is going to cost me some money (I pay for the car benzine), but the cost might go as high €157, 1169 DKK, $210, 25.000 ISK (current exchange rates) just for gas (on an car) for that trip. So if anyone can help with this cost it would be welcomed. Thanks for the support! 🙂

Update 1: I am most likely going with the bus. But that also costs some money, around 3900 ISK, 182 DKK, 24€. $32, 20GBP (Current exchange rates).

Blog post updated at 13:12 UTC on 12 December, 2011.

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Earthquake activity in Katla volcano

Even if there is December and Katla volcano is supposed to have less earthquake activity during this time of year. It seems to be that currently that is not the case. But the earthquake activity is less then it was this summer after the minor eruption in July 2011. No major earthquake swarm has been taking place in Katla volcano for the past few weeks. But there is a lot of earthquakes taking place, without it being a earthquake swarm at one single location inside Katla volcano.


Current earthquake activity in Katla volcano. Copyright of this image belongs to Iceland Met Office.

Many people might ask if this earthquake activity is something to worry about. The answer is no. Katla volcano is unlikely to start an eruption in December. But if this pattern of earthquake activity it is clear that Katla volcano is going to erupt sooner rather then later. But the question after the mini-eruption last summer (July 2011), if there are going to be around 10 years until next eruption takes place in Katla volcano. For the moment nobody knows for sure.

Other: I want to remind people about the forum. It can be used to ask questions, chat, share pictures and so on.

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Harmonic tremor in El Hierro volcano drops

There was a change in the eruption in El Hierro volcano last night. The harmonic tremor started to drop of slowly. This drop in harmonic tremor comes several days after a drop in earthquake activity happened. But it might be possible that this drop in earthquake activity in north El Hierro volcano might be because a erupting vent did open up in north El Hierro volcano. But at such depth that the eruption was not noticed on the surface on the ocean. At least that might be the reason. But without any data, this is just a speculation. But at any rate, the earthquake activity in north part of El Hierro volcano has dropped down to almost zero in few days time.


The harmonic tremor yesterday (5 December, 2011). The drop in harmonic tremor can clearly be seen here. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The harmonic tremor today at 08:15 UTC. The harmonic tremor continues to drop during the past few hours. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

The harmonic tremor drop is something that has happened before in El Hierro volcano. Just before a new fissure did open up in El Hierro volcano eruption. I am unsure if that is the case now. But it should become clear in about two to three days. But it is also a possibility that this eruption is coming to a end. But it has been erupting now for close to three months now. So this eruption might just ending. But we might have to wait a bit until that is confirmed. But at the moment the harmonic tremor is dropping and that means the eruption is smaller for the moment.

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Harmonic tremor pulse in Grímsfjall volcano

There have only been seven months since (May 2011) the last eruption in Grímsfjall volcano. But it seems that Grímsfjall volcano is getting ready for its next eruption. Even if the last eruption was the largest one for at least 140 years in Grímsfjall volcano. So far earthquake activity remains low in Grímfjall volcano. But I am not sure if that means anything for the moment. But there has been in earlier lead up to a eruption a build up of earthquake activity in Grímsfjall volcano.

Today at least two harmonic tremors spikes have been detected by IMO. But this type of harmonic tremor pulse have been detected before in Grímsfjall volcano. Older blog posts on that subject can be found here and here. But this time around it seems that the harmonic tremor is stronger then before. Currently it remains uncertain of there is a glacier flood starting from Grímsvötn lake, as was the case last time this type of harmonic tremor pulse was detected in Grímsfjall volcano.


Harmonic tremor in Grímsfjall volcano at 00:21 UTC on 5 December, 2011. Copyright to this picture belongs to Iceland Met Office.


The harmonic tremor in Grímsfjall volcano at 01:39 UTC on 5 December, 2011. Copyright to this picture belongs to Iceland Met Office.

There is a clear change in the harmonic tremor, as can be seen here. But why and what this actually means for Grímsfjall volcano I am not sure. But I am rather sure that this means a new eruption might only be several months away. But it is hard to know that for sure. But I am just base my estimate on earlier experience with Grímsfjall volcano. But it might not mean anything after last eruption.


The GPS data from top of Grímsfjall volcano. The data is missing for the last few days. Must be because of snow and ice. But given the last data set, the change so far it not that great since the eruption last spring. Copyright to this picture belongs to Iceland Met Office.

What happens next in Grímsfjall volcano is a big question. But it seems that Grímsfjall volcano is going to go for a new eruption. When that might happen I have no idea.

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Activity remains low in Iceland. Eruption continues in El Hierro volcano

At the present time the earthquake activity remains low in Iceland. This goes for both Katla volcano and other areas of Iceland. This is the regular quiet time in Iceland, as it happens sometimes. For the next days, there is a risk of frost-quakes as the ground freezes over in a cold snap.

El Hierro volcano, Canary Islands

The eruption in El Hierro volcano continues as before. New eruption vents have been opening up at random in the south part of El Hierro volcano. Earthquake activity to the north has dropped. While at the same time, the earthquake activity seems to have increased slightly to the west part of El Hierro volcano. I am not sure why that is yet.

In the tremor data. I have been seeing several explosions taking place. But they create a spikes in the tremor plot, that is different then what happens when a earthquake takes place.


The current harmonic tremor from El Hierro volcano. Explosions are the spike activity (30 November, 2011). Some of this however might be sudden increase in eruption activity. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

Other then that. The eruption in El Hierro volcano seems to be about the same for the moment as it has been for the past almost two months now. So far it is impossible to know when this eruptions ends. But eruption in La Palma volcano lasted about one month on average. Eruptions in Lanzarote volcano have lasted about three months (last eruption was in the year 1824). Based on this. This might be a eruption that lasts for about 3 to 5 months at the longest in my opinion. But what actually happens is just something that is a wait and see matter.

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Update on the weekend activity

Iceland

This weekend was quiet in Iceland. There was almost nothing going on. There was only one small earthquake swarm in Krýsuvík volcano. But this earthquake swarm was tectonic in nature, not volcanic. The largest earthquake in this earthquake swarm was about ML3.2 in size. Few earthquakes where in Katla volcano, but less this weekend then many others. But it is normal for Katla volcano to be quiet during November to March each year due to snow that is added to the glacier. But that increased the pressure of the glacier on top of the magma chamber (floating balance laws at work here).

Mainland Spain

There was a flurry of earthquakes on Mainland Spain during the weekend. None of this earthquakes where felt, from what I can gather at IGN web site.

Canary Islands, Spain

The eruption at El Hierro volcano continues as it has done for the past almost two months now. The harmonic levels are about the same as it has been, but there seems to be minor intermittent in activity from El Hierro volcano. IGN has setup a picture web site with images that show the activity since this eruption started clearly.

Erik at Eruption blog has good blog post about the magma mixing that appears to be taking place in the eruption in El Hierro volcano.

Other then this. Is is all quiet in Iceland for the moment. But frost-quakes should be expected in the next 48 hours or so in Iceland. As the ground freezes over in a really cold weather.

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Update for the eruption in El Hierro volcano

As the eruption in El Hierro volcano moves closer to the second month. Information on what has been going on has gone bit hard to come by (for me anyway). As people settle with there new reality (erupting volcano). But that does not stop me from reporting on it.

The current status of the eruption is that nothing much has changed since last blog post. But yesterday there where reports of new vents opening up off the south coast of El Hierro volcano. But this is the area where current eruption has been taking place the past month and a half. It remains to be seen if that is going to change or not. But earthquake activity has continued in north part of El Hierro volcano. This earthquake activity seems to be a mixed one. But that means there are both earthquakes due to dike intrusions and local tectonic earthquakes. I now think that this earthquake activity is going to continue all the eruption. I am not sure why a eruption has not started in north part of El Hierro volcano yet. But for the moment it is just earthquakes. The strongest earthquakes in this area can go up to Mb5.0 in size. But I base that on what type of rock makes up the area, along with the thickness of the crust. But that is from 10 km thick.


The earthquake activity for the past 48 hours in El Hierro volcano (picture from 22 November, 2011). Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


Earthquake activity in El Hierro volcano for the past 4 days. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The earthquake activity from July 2011. This earthquake activity maps out well where the magma lies in the El Hierro volcano. But as the magma expands in the crust, it creates earthquake activity. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

The harmonic tremor tells me what is going on in the eruption, when I lack all other visual data on what exactly is going on. But the harmonic tremor increases or drops depending on the strength of the eruption. But that aspect of the eruption is based on how many and how large fissures are open at the time.


The harmonic tremor as it is today (22 November, 2011) at 21:11 UTC. The eruption as can be seen is around the same level as before. But this is not the strongest the harmonic tremor has been. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The harmonic tremor when the eruption was more active then today. This can clearly be seen by how the harmonic tremor is stronger then the scale of the harmonic tremor plot. This happens when a new fissure opens up and its eruption is at the strongest. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

The IGN web site on El Hierro volcano eruption can be found here. But it is in Spanish.

I am continuing to monitor this eruption. Even if it is a long term eruption, but that are eruptions that are longer then 1 month. As the for the eruption as a whole, little change has taken place in terms of strenght and location of the eruption. But that might change without warning as before.

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Possibility of a new fissure has opened up in El Hierro volcano eruption

It seems by the harmonic tremor data that a new erupting fissure has opened up somewhere in El Hierro volcano. But given lack of visual observation I do believe that this fissure is at really great depth, and is not leaving any signs on the surface that a new eruption is taking place. Where this new fissure might be is unknown to me at present time. But based on the harmonic tremor data this new eruption seems to be powerful one. It should be expected that new fissures opens up a random while El Hierro volcano is erupting. So far the fissures that have been opening up have been short and out in the ocean. It should also be expect that erupting fissures stop erupting for no reason and with no warning at all. This seems to have happened as I am writing down this blog post.


The harmonic tremor from the eruption in El Hierro volcano yesterday. It can be seen on this harmonic tremor chart that the eruption was powerful all yesterday. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The harmonic tremor around 22:07 UTC. At that time the eruption was in full power as can be seen. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The harmonic tremor at 22:46 UTC. Notice how the drop is sudden when the new eruption fissure stops erupting. What happens is that the magma source that fed the erupting fissure did dry up. Why and how that happens in unknown to me. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

This might mean that a new fissure might open up in the next few hours to days. Where that might happen is impossible to know. But as the fissures have been open up so far, it is going to be in a North – south line (about) in El Hierro volcano. What has however become a problem in my opinion is that the magma might have “boiled” the rock and made it soft. So it might not make a earthquakes before a eruption starts in it. This might be the case if the magma has been in the crust for the past 5 weeks. But the only example of that type of event that I know of was in Eyjafjallajökull volcano last year (2010), when a new fissure did open up suddenly and without any earthquakes or warning after 4 weeks of eruption. The reason for that was the same one on what I think might be happening in El Hierro volcano.

From what I can tell, based on data and earthquakes it does not seems that the eruptions in El Hierro volcano are over. As new magma continues to flow in from depth (the mantle). Until that flow stops, El Hierro volcano is going to continue to erupt. However there might be breaks from few hours and up to several weeks between eruptions, in that case no eruption would be taking place. This has its origin in the fact that this is a fissure rift events of shorts, a similar eruption took place in Krafla volcano in Iceland for over a 10 year period. Movement and flash inflation and deflation are also to be expected during this period in El Hierro volcano eruption. As it has many similarities of the eruption in Krafla volcano in Iceland. But it is not exactly the same, just similar. As Krafla volcano is on the inter-plate rift zone. While El Hierro volcano is on a hot spot rift zone, far inside the Africa Plate.

Update on the forum: There have been some technical difficulties with the whois registration. How that works out is not yet clear. I am going to short that issue out before I set-up the forum on the domain. In the case I have to register a new domain name. What happens in this case should be come clear next week I hope.