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Few words about my geophone network

As many know. I run a geophone network in Iceland. This is my personal network. I have for most part funded it all on my own. But the last two geophones where exception to that. As I did fund them with donations from this web site. That made it possible to setup geophones at Eyrarbakki and at Skeiðflöt, a geophone that is close to Katla volcano.

My geophone network is not complex. It is build up on Mark Products 4.5 Hz 3 component geophone, like this one here. I also have to use analog to digital board and an amplifier. Both I buy both from the same supplier. I also have to use a PC with every geophone station. That is the hardest part of the setup, as PC often fail without reason and with age. For that reason I plan to move to something else in the future. Something that is not PC powered. Having this geophone network allows me to watch the areas where I keep them in real time if something of interest happens. Like an earthquake swarm or a eruption.

Sensitivity of the geophone network

I have setup my geophone network in a such way that it is sensitive to earthquakes. The smallest earthquakes that I can detect in a good weather is somewhere around -2.0ML really close to the geophone. This means in the instance of Katla volcano, that I can see earthquakes down to ML0.2 in magnitude. But I did that this evening, and I did detected that earthquake trough an high noise level. In the case of Heklubyggð geophone (Hekla volcano) and Skeiðflöt (Katla volcano). I am clearly going to see any harmonic tremor that those two volcano are going to make when an eruption starts, when ever that might be.

Wind noise is an constant problem on my geophone network. There isn’t anything that I can do about it. As isolating setup requires a lot of money and a lot of work to setup and maintain properly. Something that I cannot afford. I also cannot do this. But I do try to insulate the geophones with some cheap ways, like keeping them indoor and placing an cheap plastic bucket on top of them with some insulating material. But that does not work in the worst storms that pass over Iceland during the winter. But works well against minor noise in the environment.

All that my geophones record can be viewed online here. The images are updated every 5. min.

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Earthquake swarm on Reykjanes Ridge this morning

This morning at 05:48 UTC an earthquake swarm started on the Reykjanes Ridge. The earthquake swarm is believed to have been created by an dike intrusion in the area. Around 40 earthquakes have been recorded so far, the largest ones have had the size over ML3.0 in magnitude. But at the moment the earthquake swarm has stopped or is doing some idle time. As this earthquake swarm was created by an dike intrusion. It is not impossible that is going to resume in few hours to days time. But it is hard to know for sure what happens next in this area.


The area of activity. Please note that some earthquakes have wrong location due the distance from the SIL network. Copyright of this picture belongs to IMO.

This activity of dike intrusions suggests that this area of Reykjanes Ridge is getting more active then it has been since the year 1926, when the last confirmed eruption took place. But there might have been unconfirmed eruptions on the Reykjanes Ridge in the years 1966 and in 1970. It is also most likely that dike intrusion activity is going to continue for some time now. But as I sad above, it is impossible to know how long the breaks are going to be between activity episodes. Last large earthquake swarm in this area took place in early 2010 (Erik blog post about it can be found here). That activity was about one month before the eruption in Eyjafjallajökull volcano.

Largest earthquakes of this earthquake swarm appeared clearly on my geophones where the noise level was not too high. They can be viewed here on the 24 hour plot.

Icelandic news about this activity. Use Google translate and hope make sense of it.

Skjálftahrinan í rénun (Rúv.is)
Skjálftar við Eldey (Rúv.is)
Jarðskjálfti upp á 3,8 stig (mbl.is)
Á fjórða tug skjálfta við Eldeyjarboða (DV.is)

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Eruption in Etna volcano

Tonight around 21:00 UTC an eruption started in Etna volcano. From the views of the web cameras that watch Etna volcano. This eruption seems to be rather small. I do not expect it to get any bigger.


Web camera picture of the eruption in Etna volcano. Copyright of this picture belongs to Radio Studio 7, Italy.


Web camera picture of the eruption in Etna volcano. Copyright of this picture belongs to Radio Studio 7, Italy.

Eruptions in Etna volcano are frequent, so this event is no surprise that it is currently taking place. Live web camera feed can be found here.

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More earthquake activity in Katla volcano

Yesterday (05.02.2012) there was an new earthquake swarm in Katla volcano. This activity suggests that it was due to dike intrusion as before in the Katla volcano caldera. The largest earthquake was ML2.1 with the depth of 0.1 (~100 meters) km. So this where really shallow earthquakes this time around.


The location of the earthquake swarm in Katla volcano yesterday. Copyright of this picture belongs to IMO.

This pattern of activity has been ongoing since July 2011, when a minor eruption took place in Katla volcano caldera. I am expecting this pattern of activity to continue for some time now. For how long I do not have any idea. It depends if this going to end in a larger eruption then took place in Katla volcano in July 2011 or if this is going to quiet down one day for several more years.

Activity in Katla volcano can be observed on Iceland Met Office pages. It also can be observed on a geophone that I run in Skeiðflöt (website here), a farm located few km south of Katla volcano.

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New hot springs in Greenland after an earthquake (swarm?)

While hot springs are in few areas of Greenland. They are not common and not as hot as those in Iceland. I do not know a lot about the details of geology of Greenland. So I am unsure on the details why there are hot springs in Greenland to start with. But this news is even more interesting for that exact reason.

According to the Greeland Radio new hot springs opened up in the village of Kangersuatsiaq of the west coast of Greenland. After an what appears to be swarm of earthquakes, with the largest one somewhere around ML2.9 to ML3.? (enough to sake people pictures on the wall). A new hot springs did open up following this earthquakes. The water seems to be around 20C to up 36C. It might be warmer, as details on this are few and little.

Best to my knowledge there is no known volcanoes in this area and have not been in the past ~65 million years or longer.

News about this in Danish and Icelandic.

Flere varme kilder i Kangersuatsiaq (KNR.gl)
Jordskælv ved Kangersuatsiaq (KNR.gl)
Vorlykt við glænýja grænlenska hveri (Rúv.is)

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Earthquake swarm in Hengill volcano

There was an earthquake swarm starting in Hengill volcano. This earthquake swarm is at the usual location, close to the hydro-thermal power plant. But this earthquakes happen as the hydro-thermal power plant pumps down cold water into the ground.

This earthquake swarm started at 18:08 UTC on 04.02.2012. The largest earthquake so far in this earthquake swarm is an ML2.5 in magnitude according to automatic results from Iceland Met Office.


The earthquake swarm in Hengill volcano. Copyright of this picture belongs to IMO.

It is hard to know for sure if this is just the start of the earthquake swarm or not. But earthquake swarm have been common in this area over the past few months due to water being pumped down into the ground.

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New earthquake swarm in El Hierro volcano

During the past few days there has been an earthquake swarm in El Hierro volcano in Canary Islands. Following this earthquake swarm there has been some increase in eruption activity. Resulting in some material reaching the surface of the ocean. The reason for this activity is that new magma is being injected into El Hierro volcano from depth. This magma is pushing the magma that is already there closer to the surface, creating dikes and sills in the rock along the way. This also increases the eruption in already open vents.


The harmonic tremor activity in El Hierro today. Copyright of this picture belongs to IGN.

The largest earthquakes in this swarm have had the size ML2.7 and ML3.4. They have been taking place at the depth of 12 to 15 km, based on early data from IGN.


The ML3.4 earthquake in El Hierro volcano that did happen during the night. Copyright of this picture belongs to IGN.

I am expecting this activity to continue for some time now. As it seems that more magma is coming up from depth. How long that progress is going to last is impossible to know. When it stops, it does so and only then the activity in El Hierro volcano is going to stop.

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First earthquake detected on Skeiðflöt geophone

This here is the first earthquake that I properly detect on my new geophone at Skeiðflöt farm. This is an ML2.0 earthquake in Katla volcano caldera according to IMO automatic SIL network. Even if there is high noise level I was still able to record it clearly. I might have recorded smaller earthquakes already. But they do not appear clearly so it is hard for me to be sure at the moment if I actually recorded them due to high levels of background noise.


The ML2.0 earthquake in Katla volcano caldera. This is based on automatic data and might not be 100% correct. This picture is released under CC licence. See Licence web page for more details.

This is promising for many reasons. It means that I can see earthquakes clearly even if there is high background noise level taking place at Skeiðflöt geophone. This also means that I am clearly going to see harmonic tremors and other events in Katla volcano, even in the glacier also. But this also depends on the noise level at the time. I do hope that the noise level is lower in summer then it is during the winter.

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Minor dike intrusion into Bárðarbunga volcano and earthquakes deep south of Iceland

Yesterday (03.02.2012) at 10:42 to 10:47 UTC there was an minor dike intrusion into Bárðarbunga volcano. Based on the earthquake activity and the depth that they where on. It seems that they did not go close to the surface. Based on the earthquake pattern, the dike intrusion did only go up to the depth of 12 km. But this dike intrusion did rise up from the depth of 22 km.


The dike intrusion into Bárðarbunga volcano. It can be seen by the dense earthquake swarm in Bárðarbunga volcano. Copyright of this picture belongs to IMO.

It is hard to know what this means. But it is for sure an clear sign of more activity in Bárðarbunga volcano. But this is no clear sign that an eruption might be about to take place in the nearby future.

Reykjanes Ridge

Yesterday (03.02.2012) there was an earthquake swarm deep south of Iceland. This earthquake swarm was located on the Reykjanes Ridge. It is impossible to know for sure what was going on at this location due to distance from land. But the average distance of this earthquake swarm is about 450 km south of Eldeyjarboða on the Reykjanes Ridge. The recorded size of this earthquake swarm was from ML3.1 to ML3.3. But that is most likely an underestimate of the earthquake size due to distance from the SIL network.


The star mark the earthquakes. Copyright of this picture belongs to IMO.

Other then this it has been quiet in Iceland. But that has more to due with storms and bad weather. But it has also been quiet in Iceland during the past few weeks. It might continue like that for some time now. When this ends is impossible to know for sure.

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Skeiðflöt geophone is up and running

Today I started the geophone at the farm Skeiðflöt. It is just south of Katla volcano. Some setup spikes are on the webicorder plot at the moment. But they should be clear off in the next 24 hours.

Currently there is bad weather in the area and it seems to show on the geophone at Skeiðflöt. But this new geophone adds to the sensitivity of my network and allows me to see earthquakes down to ML0.0 in good weather taking place in Katla volcano. But all large earthquakes should appear on this geophone regardless of most weather conditions outside. This geophone also increases my chances of seeing earthquakes in Eyjafjallajökull volcano if any take place to start with (it has been quiet after the eruption in the year 2010).

All my currently online geophones can be viewed online here. The webicorders are updated every 5 min.