Category: Magma

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Special report: Eruption at El Hierro volcano, Canary Islands

At 04:18 UTC on 10 October, 2011 a eruption did start somewhere close to the El Hierro volcano Island (but inside El Hierro volcano system). So far nothing has been seen to this eruption, so location is uncertain at the moment. At the moment this eruption has only been confirmed by harmonic tremors seen on seismometers on El Hierro island.

From what I can tell, based on the harmonic tremor plots. It seems that the eruption has been growing in size since it started well over 12 hours ago. This suggests that the eruption is growing in size. That also brings up the issue that new fissures might open, both into deeper ocean and on shallower depth and even on land without any warning at all.


The harmonic tremor from El Hierro at 21:08 UTC on 10 October, 2011. Copyright of this picture belongs to Instituto Geográfico Nacional.

A location for the eruption has been suggested, as can be see on this map here.


The speculated eruption in El Hierro. Copyright of this picture belongs to el-mundo.es Thanks to Dr. John v. Kampen for this map via email.

Lack of earthquakes does not mean that magma is not the move and has not reached the surface already. But this however suggests that magma now has a free flow upwards to the surface since sometimes yesterday, when the earthquake activity did drop suddenly from ~100 earthquakes to ~30 earthquakes over the day.


Current earthquake activity in El Hierro. It is my personal opinion that the eruption is around -18.05 and 27.65 to 27.70 (middle of that area, around 450 meter depth). Copyright of this picture belongs to Instituto Geográfico Nacional.


Spectral image of the harmonic tremor. This image clearly shows that the orgin of the harmonic tremor is magma on the move. Not something else. Copyright of this picture belongs to Instituto Geográfico Nacional.

I am going to update this blog post as more is known about the eruption in El Hierro.

Canary Island news about this. With thanks to Dr. John v. Kampen how did send them to me in a email.

Posible erupción al sur de El Hierro (Youtube, Spanish, Video)
¿Emergerá una nueva isla? (Youtube, Spanish, Video)

Blog post updated at 21:49 UTC on 10 October 2011.

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Tremor pulses in Hamarinn volcano (most likely)

During the past two weeks there have been tremor pulses in Hamarinn volcano (is claimed to be part of Bárðarbunga volcano system), at least most likely that volcano. But it might also be a volcano that I call Skrokkalda Volcano (other name might be Hágöngur volcano) (it has no entry on GVP web page, I do not know why). But given recent history I find it unlikely to be the case.

This harmonic tremors might be due to dike intrusions. I find it unlikely to be from a man made lake called Hágöngulón that is in this area. The harmonic tremor pulses look like sharp spikes on the tremor plot on the Skrokkalda SIL station.


Harmonic tremor spikes from Hamarinn volcano. Copyright of this picture belongs to Iceland Met Office.

This pattern of harmonic tremor spikes was seen all last year and all of the year 2009 from what I can remember. I do not have tremor charts from that period. But however this suggests that more magma has now started to flow into Hamarinn volcano. But there was a small volcano eruption (it seems so, given the flood that took place in July) in Hamarinn volcano last summer (summer 2011). What happens next is a good question.

This process of inflow of magma seems to without earthquakes, or close to it. I do not know why that is and I have no ideas that explain it.

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Update on Katla volcano earthquake swarm

There has not a lot changed in the past few hours since the earthquake swarm did start in Katla volcano. Eruption has not yet started in Katla volcano and when it might start is still a mistery.

Current map of the earthquake activity.


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

Here are traces from my Heklubyggð geophone. But that is currently the geophone that I have that is closest to Katla volcano. I am collecting donations so I can buy two new geophones. The blog post about that can be found here. I do not expect to have the geophone in place before a eruption starts in Katla volcano this time around. So far the donations are up too 5,410.74 DKK, so I am not far from what I need to collect. I do not have to pay customs of this according to a email I got from the customs office when I did ask about it. But I have too pay 25,5% VAT on this when it gets here. That might be a good amount I think in Icelandic Kronas (ISK).


One of the large earthquakes. This is not the strongest earthquake in the earthquake swarm that took place this morning in Katla volcano. This is also a double earthquake, that is two earthquakes taking place at the almost the same time. That is the reason for the odd looking wave form on this earthquake trace. This picture is released under Creative Commons licence. See Licence web page for more details.


A ML3.0 earthquake that took place in Katla volcano this morning. This picture is released under Creative Commons licence. See Licence web page for more details.


The largest earthquake in the earthquake swarm this morning. Its size was ML3.55 with the depth just short of 1 km. This picture is released under Creative Commons licence. See Licence web page for more details.


A ML2.94 earthquake in Katla volcano this morning. This picture is released under Creative Commons licence. See Licence web page for more details.

So far it has quieted down in Katla volcano. But that does not mean a lot. As magma can go on the move at any time. Without any warning at all. So monitoring Katla volcano is important with that fact in mind. According to Iceland Met Office, this is the largest earthquake swarm in Katla volcano caldera since the year 2002.

I am expecting more strong earthquakes to take place in Katla volcano. But it is impossible to know when a new earthquake swarm might start in Katla volcano and how large and long it is going to last. For the moment, it is just wait and see.

Iceland Met Office has put up a news about this in English. Thanks too the readers how pointed this out!

Earthquake activity in Katla volcano October 2011

Icelandic News about this earthquake swarm.

Snarpasta hrinan í Kötlu frá 2002 (Rúv.is, Icelandic)
Snörp hrina í Mýrdalsjökli í nótt (Rúv.is, Icelandic)
Snörp hrina í Kötlu (Vísir.is, Icelandic)
Sterkir skjálftar undir Mýrdalsjökli (mbl.is, Icelandic)
Um 20 skjálftar yfir 2 stig (mbl.is, Icelandic)

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Large earthquake swarm in Katla volcano

At 02:45 UTC a large earthquake swarm did start in Katla volcano. I do not know if this an start of a eruption in Katla volcano or not. For the moment it is too early to know for sure. I have to wait few more min before that becomes clear on the harmonic tremor plots. The largest earthquake so far according to the automatic SIL systems is a ML3.9 earthquake.


The earthquake swarm in Katla volcano. The second green star is from a fake ML3.3 earthquake from yesterday. Copyright of this picture belongs to Iceland Met Office.


The harmonic tremor plot on Slysaalda SIL station at 03:04 UTC on 5 Október 2011. Copyright of this picture belongs to Iceland Met Office.

It takes a few moments to become clear if Katla volcano is starting a eruption or not. I am going to post updates as this situation changes if I have too.

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Magma on the move in El Hierro, Canary Islands

This is happening faster then I expected. But it seems that magma is now on the move upwards in El Hierro volcano in Canary Islands. This is evident by the earthquake patterns that are emerging from the volcano. Given the earthquake locations, most likely place for a eruption to take place is out on the ocean based on that. But sometimes magma can find different pathways up the surface without a lot of warning.


Latest earthquake map from Instituto Geográfico Nacional that shows clearly the earthquake pattern since the dike intrusion did start in El Hierro. Copyright of this picture belongs to Instituto Geográfico Nacional.

At the moment it is impossible to know when and where a eruption might start. It depends on many factors. But it is now clear that magma is on the move upwards. So far the magma seems to be around 10 km up in the earth crust under El Hierro. So it is clear that the magma is on the way up and most likely preparing for a eruption.

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What is happening in El Hierro volcano

This is a special blog post about the volcano El Hierro in the Canary Islands. The resons for this blog posts are those that this activity is interesting and there is not a lot happening at the moment in Iceland due to bad weather (nothing gets recorded in this bad weather).

Currently El Hierro volcano is a phase that I personally call a magma intrusion phase (I have no other word for it). But that means that magma is currently coming from a depth, that is more then 20 km below the volcano and up the crust directly below the volcano. It is impossible to know how long this phase is going to last. As a example this phase for Eyjafjallajökull volcano lasted for good part of 17 years (with some breaks). When the pressure is high enough in the sill that is now forming in El Hierro the magma is going to break up the surface.

This pattern can clearly be seen on this image here.


The magma is flowing up into the volcano at around 30 degree angle from the depth of more then 20 km. When a new magma injection starts, a new earthquake swarm starts in El Hierro. This magma injections are different in size and length. But as more magma collects into the bedrock in El Hierro the stronger earthquakes are going to take place. But this increases the pressure on the rock and inside the magma chamber that is now forming and can clearly been seen with the earthquake pattern. Copyright of this picture belongs to Instituto Geográfico Nacional.

I did see a picture that was made on Eruptions blog that did show his clearly, both the feeder channel of the magma and the magma chamber that is currently in the making. It seems that magma inflow into the new magma chamber or the sill in El Hierro is stable at the moment. But I base that view on the constant earthquakes that are currently taking place. But this magma inflow seems to have been stable since 16 July, 2011 when the magma started to push upwards into El Hierro.

Earthquakes that signal new inflow of magma do not need to be strong in size. But they are deep, with the most depth around 20 km. But the crust in this area is around 10 to 26 km thick. As this is a ocean crust in this area. But the Canary islands are the thickest crustal part in the area. But it is also important to notice that the magma chamber or the sill is expanding in all directions, not just upwards. That in it self is also going to create deep earthquakes. But those earthquakes should remain a bit outside the main area of the deep earthquakes that are currently taking place in the area.

I am expecting a lot more earthquake activity when or if El Hierro starts erupting. But when that might happen impossible to know for the moment. The only thing that can be done is too wait and see what happens.

Update 1: Here is the earthquake activity for today (30 September, 2011).


Earthquake activity of today (30 September, 2011). There is less earthquake activity today. This happens when magma flows into a volcano. This did also happen with Eyjafjallajökull volcano in the year 2010. If anyone has the direct link too this plot, please leave it in the comments. Thanks. Copyright of this picture belongs to Instituto Geográfico Nacional.

Update 2: Links too El Hierro information can be found here.

Update 3: The Spanish news channel Canal 24 can be found here and it is live.

Update 4: Here is a news in english about the evacuation of El Hierro. It is from 28 September, 2011. Evacuation of El Hierro begins as fears of volcanic eruption grow. Thanks to Dr. John v. Kampen that did send this to me with a email.

Note: There are new pictures of Eyjafjallajökull volcano, Fimmvörðuháls craters here. They show the difference from the year 2010 and in the year 2011. The text is in Icelandic.

Also. Please support my effort so I can buy two new geophones and add them to my monitoring network in Iceland. Thanks! 🙂

Blog post has been updated 30 September, 2011 at 22:12 UTC.
Blog post has been updated 30 September, 2011 at 22:25 UTC.
Blog post has been updated 30 September, 2011 at 23:08 UTC.
Blog post has been updated 1 October, 2011 at 14:48 UTC.

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What did happen in Hamarinn volcano yesterday

I really did think that a eruption was about to start in Hamarinn volcano yesterday. As the signal that I was seeing was not far from what I did see on 12 July, 2011 when a eruption did take place for sure in Hamarinn volcano.

Here is the tremor signal from 12 July early in the morning.


The harmonic tremor signal on 12 July, 2011 at 07:49 UTC. Copyright of this picture belongs to Iceland Met Office.

Here is the signal on the 27 September, 2011.


The harmonic tremor signal on 27 September, 2011 at 09:34 UTC. Copyright of this picture belongs to Iceland Met Office.

The tremor signal in July was stronger, but it looks almost the same way as the signal yesterday (27 September, 2011) did. So I think I know what did happen yesterday (27 September, 2011) in Hamarinn volcano. There might have been a minor dike intrusion into Hamarinn volcano. There where no earthquakes as it might have been going up resistance free pathway. But it is hard to know that for sure at the moment. Later events might however make what happened yesterday more clear what did happen on 27 September, 2011.

Note: I am looking for data on El Hierro volcano. As I am going to make a special blog post about it soon. I am looking for everything that I can get my hands on and might be useful to me.

Note 2: I have updated this blog post here and added the most recent eruptions in Iceland. Blog post: A short history of volcano eruptions in Iceland

Blog post updated at 12:59 UTC on 28 September, 2011.

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No eruption starting in Hamarinn volcano

There seems to be a minor eruption starting in Hamarinn volcano (might be part of Bárðarbunga volcano). Given the current tremor signature on Skrokkalda SIL station.


The start of a harmonic tremor spike on Skrokkalda SIL station. Most likley from Hamarinn volcano. Copyright of this picture belongs to Icelandic Met Office.

For the moment I do not know if this is going to remain a small eruption or might evolve to larger eruption. That is going to come clear in next several hours. But for the moment this is starting and glacier flood is to be expected in several hours. There is no danger to humans or humans structures I think.

Update 1: Darn! False alarm!

This is how the tremor plot did look after one update.


The tremor spike just changed into regular earthquake so to speak. So this is nothing but false alarm. It happens. Copyright of this picture belongs to Iceland Met Office.

Blog post updated at 09:59 UTC on 27. September 2011.

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Small eruption took place in Katla volcano in July 2011

According to the news on Rúv this evening it is now a opinion at Icelandic Met Office that a small eruption did take place in Katla volcano during the days 8 and 9 July 2011. This eruption was however larger then the eruption in Fimmvörðuháls in Eyjafjallajökull volcano last year (2010). But this is based on tremor data from around Katla volcano during this summer. But this is what Einar Kjartansson geologist at Iceland Met Office says in the news at Rúv this evening. Even if this small eruption did take place in Katla volcano it does not seems to have eased the pressure inside Katla volcano, so a large eruption in Katla volcano is still a possibility in the close future. Note: GVP has updated Katla volcano eruption status to the year 2011!

This conclusion was reached by checking out the cauldron that formed during this event. But they show a sign that they had a sudden melt taking place. But that melt can only happen of lava got into contact with the ice and fast melted it. This is also the reason why there was a 5 meters flood in Múlakvísl glacier river that did destroy the bride over it. But it is also a fact that the harmonic tremor in Katla volcano during this period was the same as that did happen during the eruption in Eyjafjallajökull volcano. The only difference was that it it was stronger from Katla volcano then in Eyjafjallajökull volcano it seems (at least from what I can see from the data). Even if it lasted for a shorter time then in Eyjafjallajökull volcano.


The tremor on Slysaalda SIL station on 9 July 2011 at 00:36 UTC. Copyright of this picture belongs to Iceland Met Office.


Alftagrof SIL station on 9 July 2011 at 00:36 UTC. Copyright of this picture belongs to Iceland Met Office.


The area that was active and had a eruption on 8 and 9 July 2011. Copyright of this picture belongs to Iceland Met Office.

Even with this small eruption it is clear that Katla volcano is not done with its eruptions. Since the large one is not yet over. When that happens is a good question and nobody has a answer too at the moment.

Note: This is also what did happen in Hamarinn volcano the week after. But I also think that volcano did have a minor eruption in July 2011. As the signatures are the same from what I can gather. So that makes three eruptions in Iceland for the year 2011 if confirmed later on.

Icelandic News with this. Use Google translate with care on it. Since it does not understand.

Allt bendir til Kötlugoss (Rúv.is, Icelandic, Picture)
Segir Kötlu hafa gosið í sumar (DV.is, Icelandic, Picture)
Lítið eldgos í Kötlu í sumar (mbl.is, Icelandic)

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Earthquakes in Katla volcano, strong sulphur smell in Múlakvísl river before the earthquake happened

This morning there has been some earthquake activity in Katla volcano. But it has also been reported in the news this morning that a really strong sulphur smell was found around 06:00 UTC on nearby farm to Múlakvísl river this morning. But this was before the earthquake did happen. I am not sure if this sulphur smell continues to be felt in the area close to Katla volcano. No changes in water hight has been detected in Múlakvísl glacier river.

The ML2.6 earthquake in Katla volcano was on 2.3 km depth. This was mostly a dike intrusion into the bedrock of the Katla volcano caldera.


The earthquake swarm this morning in Katla volcano. Copyright of this picture belongs to Iceland Met Office.


High resolution of the Katla volcano earthquake this morning. Along with correct depth and size. This picture is released under Creative Commons licence. See Licence page for more details.

As before. This is just a wait and see what is going to happen in Katla volcano as before.

Icelandic News of the sulphur smell in Múlakvísl glacier river.

Brennisteinslykt fannst við Múlakvísl í morgun (Vísir.is, Icelandic)
Brennisteinslykt við Múlakvísl (mbl.is, Icelandic)

Update 1: According the news on Rúv this activity suggests that hydrothermal activity is continuing to increase in Katla volcano caldera. But the news also says that this activity is something like that did happen from the year 2002 to the year 2004, when hydrothermal activity did increase before it started to get lower again. It is also pointed out my Matthew Roberts that Múlakvísl glacier river is sensitive to changes in Mýrdalsjökull glacier and small floods can happen without any warning in it due to increased hydrothermal activity.

Rúv news in Icelandic about this.

Bendir til aukinnar jarðhitavirkni (Rúv.is, Icelandic)

Blog post updated at 13:07 UTC, 23 September 2011.