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Earthquake swarm in Katla volcano, Kolbeinsey ridge, Hveravellir geothermal area

It has been a bit busy day earthquake wise in Iceland. But there has been more activity today then in past few weeks in Iceland. But it has been really quiet for a long time now in Iceland. But let’s start with the largest earthquake of the day.

Kolbeinsey Ridge

Today at 11:11 UTC there was an earthquake with the magnitude of ML3.65. This earthquake was not felt since it was more then 100 km away from nearest human population in Iceland. The earthquake took place on Kolbeinsey Ridge. It last erupted in the year 1755. No known eruption is known in this area since then. My geophone network did record this earthquake properly. The signal was strongest at my Hvammstangi geophone station. But it was also recorded on my Heklubyggð geophone station. On other geophone stations. The signal was too weak to be properly detected by my geophone.


The ML3.65 magnitude earthquake as it was recorded on my Hvammstangi geophone. This image is released under Creative Commons licence. Please see the CC Licence page for more details.


The ML3.65 magnitude earthquake as it was recorded on my Heklubyggð geophone. It is filtered at 1Hz. This image is released under Creative Commons licence. Please see the CC Licence page for more details.


The location of the earthquake. Copyright of this picture belongs to Iceland Meteorological Office.

Hveravellir geothermal area

There is an earthquake swarm ongoing (or it might be over. I have no good way to know that currently) at Hveravellir geothermal area. I only know there is an earthquake swarm there because of the tremor recording on Hveravellir geothermal area. But only two earthquakes have been large enough to appear on earthquake map on IMO web page.


The two earthquakes that did appear on IMO earthquake map. Copyright of this picture belongs to Iceland Meteorological Office.


However, Hveravellir SIL station did show that more was going on then did appear on the earthquake map. Most of this earthquakes are too small to appear automatic on the earthquake list. Some might even be too weak to be properly located by the SIL network. Copyright of this picture belongs to Iceland Meteorological Office.


Some of this activity did also appear on Skrokkalda SIL station I think. Copyright of this picture belongs to Iceland Meteorological Office.

Katla volcano

Katla volcano did have an new earthquake swarm during the night. This earthquake swarm had around 30 or so earthquakes. Most of them where located almost in the central caldrea. This type of swarm activity has now been ongoing since end of April, when it started rather sharply with an earthquake swarm. Since then it has had many earthquake swarm. But the current rate of earthquake swarm is around 1 to 3 earthquake swarm pr. Week. Normally they are in an new area inside the Katla volcano caldera.

My geophone station at Skeiðflöt records most of the earthquakes if the background noise is not too high during that time.


The earthquake activity in Katla volcano last night. Copyright of this picture belongs to Iceland Meteorological Office.

So far. This is just normal earthquake activity. It does not signal any chance of eruption activity so far. But this earthquake pattern is interesting. What it means is a different matter. So far, nobody knows for sure at this point in time. This activity seems to change hydrothermal activity inside Katla volcano caldera. This has also created minor glacier floods from Katla volcano caldera. But the flood have been seen on instruments that record water conditions in Múlakvíls glacier river. Glacier floods are marked by higher conductivity of the water, darker color and stronger sulfur smell (rotten egg smell). What happens next in Katla volcano is anyone guess. As Katla volcano has proven to be unpredictable volcano.

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Donations and advertisements

As many have seen during past few weeks. I have been cutting down advertisements on this blog. The reason is simple. The ads that I am cutting down do not work. I get little pay from them. For that reason I have removed them. The only one left to remove is infolinks. But I am going to remove them soon as I get there payment threshold. But that is $50. At current time I only lack around $5 until I reach that threshold. It should be in the next few days to weeks I hope.

Donations

I do not know at current time if I keep the donations open up longer. As I do not get so much donations at current time. I wold like to hear from people on that before I remove that options completely. But at any rate. I am planning on changing the money aspect of this blog. Since current trial and error approach is not something that I want to continue in the long term.

For those how have been donating directly via bank it is important that you update your information. As I have moved to a new bank in Denmark, called Sydbank from Nordea. The new IBAN and SWIFT code can be found here, on the donation web page.

If I stop accepting donations. I am going to remove all the links. For those how I have promised a ebook for a donation. Don’t worry. I still remember my promise in that regard.

Future direction

As I say here above. I am planning a change on this blog. Not on what I cover. I have already tested that, and failed. I am rather changing how this blog can help me make a slightly better living then I am currently having. But I not expect this blog to become super-popular any time soon. So I do not know how that is going to work out in the long term. But one thing is clear. I am going to keep covering volcanoes and earthquakes in Iceland for many years to come.

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Possible glacier flood from Grímsfjall/Grímsvötn glacier lake (Unconfirmed)

There seems to be a glacier flood did start this morning in Grímsfjall glacier lake. Based on the tremor, the glacier flood is already subsiding or something of that nature. So far this glacier flood has not yet been confirmed by monitoring scientists. So I am unsure what exactly what is going on. But current activity seems to have started around 13. June 2012, when the tremor changed from normal background noise to higher frequency noise. This can be seen on the SIL station from Grímsfjall volcano.


Grímsfjall SIL station tremor reading. The spike marks what seems to be a glacier quake taking place. Copyright of this image belongs to Iceland Meteorological Office.

This harmonic tremor started early this morning. But it can be up to 12 to 24 hours before the glacier flood is visible in the rivers that flow from Grímsfjall volcano.


The second SIL station that tremor appears on from Grímsfjall volcano. Copyright of this image belongs to Iceland Meteorological Office.

Until there is official conformation what is exactly going on in Grímsfjall volcano. It is bit hard to know exactly what is going on there at the moment. But I hope that it is going to be cleared up in the next few hours or tomorrow. There are no signs that an eruption has started in Grímsfjall volcano at current time. It is impossible to know if that is going to change following this events that are taking place in Grímsfjall volcano.

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How to spot an earthquake on my geophone helicorders web site

I run today 5 geophones. Four of them are located in Iceland. I have one geophone in Denmark where I am living. My helicorder web site can be found here. This blog post is meant to help people on reading what takes place on this geophones. What is earthquake and what is noise. As on my geophones there is a lot of noise taking place. I have put in markers on this images for easy reading. It is my first attempt on doing that. I hope it looks decent.

This is Hvammstangi geophone station earlier today. The green line, marked as note 1 means that I lost the connection with Hvammstangi geophone station during the night. Note 2 shows a typical noise on that geophone.

The red circle on shows a small earthquake that took place during the night close to Hekla volcano. The rest appears to be just a noise from nature, wind etc. Heklubyggð is often a quiet station.

Red circle around the earthquake that took place in Katla volcano during the night. The rest is just noise, cars, human walking around, wind etc.

This is the geophone station at Eyrarbakki. It doesn’t have any earthquake that I can see. But it has plenty of noise from all types of sources. Mostly washing machines of all types, human waking around, cars, wind etc.

I hope this rather short guide helps people finding earthquakes among the noise on my geophones. It is easier to find larger earthquake then smaller on my helicorders that I have online.

Update 1: Here is a picture of a larger earthquake taking place in SISZ in the year 2011.

The earthquake is the line that crosses above the helicorder image. This earthquake however only the magnitude of ML2.0 or around that. But it was close to my geophone at Heklubyggð.

Blog post updated at 01:14 CEST on 15.06.2012.

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New earthquake swarm in Katla volcano on 11. June 2012

Today from 04:00 to around 08:00 UTC this morning. There was an earthquake swarm in Katla volcano. This earthquake swarm was not large in the magnitude of the earthquakes. With the largest earthquakes being around ML2.0 in magnitude. There has been slight increase in conductivity in Múlakvísl river following this earthquake swarm. That suggests water is now leaking from hydro-thermal vents in Mýrdalsjökull glacier. So far no change in harmonic tremor has been seen. So for now, this are just earthquakes taking place inside Katla volcano caldera.


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

It is difficult to know what happens next in Katla volcano. As it is bit unclear what is exactly taking place in Katla volcano. With the lack of harmonic tremor following this earthquake swarms. This simply might just be normal summer earthquake swarms taking place. But Katla volcano is well known for that type of behavior during the summer in Iceland. With the most earthquake activity taking place in July and August.

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Earthquake swarm in Katla volcano yesterday (07.June 2012)

Yesterday there was an earthquake swarm in Katla volcano. Over 50 earthquakes have been recorded so far. But this earthquake swarm stopped yesterday at 16:22 UTC. Most of the earthquakes where shallow, with depth less then 1 km. Largest earthquake had the magnitude of ML2.5. No harmonic tremor was detected following this earthquake swarm. But that is unlike what did happen last year, when a similar earthquake swarm took place in Katla volcano.


Earthquake activity in Katla volcano yesterday (07. June. 2012). The main areas appear clearly on this map. The small dot SE on the caldera rim is an area that became active after last years minor eruption. What is taking place there is still an mystery. Copyright of this picture belongs to Iceland Meteorological Office.

This activity appears to be similar to what happened around 9th July, 2011. But no harmonic tremors are taking place in Katla volcano following this earthquake swarm.


Earthquake activity in Katla volcano on 9. July 2011. This good to compare the earthquake activity yesterday (image above this one). Copyright of this picture belongs to Iceland Meteorological Office.


The ML2.98 magnitude earthquake that happened in Katla volcano yesterday (07. June. 2012). This is the earthquake as it was recorded on Skeiðflöt geophone station. This image is released under Creative Commons License. See License page for more details.


Same earthquake as above. But filtered at 1Hz and this is how the earthquake appeared in Heklubyggð geophone station. This image is released under Creative Commons License. See License page for more details.

So far this is just an earthquake swarm. As there are no harmonic tremor signal taking place as the earthquake swarm is taking place. I do not know if there has been any glacier flood following this earthquake swarm. But if there was. It would mean that hydrothermal vents under Mýrdalsjökull glacier have been emptying out. It happens regularly in glacier such as Mýrdalsjökull glacier.

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New pictures of Grímsfjall volcano crater

Rúv News has just published pictures of Grímsfjall volcano craters. This pictures where taken by Ómar Ragnarsson. The pictures show among them a Island that has formed inside the 1.5 km long and 800 meter wide crater that did erupt in May of last year.


The Grímsfjall volcano crater that erupted on 25. May 2011. Copyright of this picture belongs to Ómar Ragnarsson.

More pictures can be found on Rúv News web site. I recommend that people click on the images to get full size (or click and open in new tab).

Undraveröld Grímsvatna – Myndir (Rúv News, Icelandic, Pictures)

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Special report: New magma injection at depth in El Hierro volcano

While I have returned to just covering Iceland volcano and earthquake activity. It does not mean that I have stopped to watch the earthquake activity in El Hierro volcano at present time.

New earthquake activity with the depth of 15 to 28 km have been taking place in El Hierro volcano today (04.06.2012). Minor earthquake activity has also taken place on 29. May, 1. June, 3. June. But this where not many earthquakes. Nothing suggests that eruption has resumed in El Hierro volcano. However an new injection of magma into El Hierro volcano might have increased hydro-thermal activity in earlier eruption vents, or moved older magma that is already high up in the fissure that was eruption. That however does not mean that the eruption has resumed. But there is nothing in the data from El Hierro volcano to suggest that an eruption has resumed at this point.

For the moment, it is mostly quiet in El Hierro volcano. I fully expect that to continue for the time being. At least it is clear that more needs to happen in El Hierro volcano before an new eruption starts in El Hierro volcano. So for the moment, there is nothing to worry about in my opinion.