Category: Earthquakes

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New earthquake swarm east of Grímsey Island

This night there where two minor earthquakes on TFZ (according to the Richter scale). According to automatic results from Iceland Meteorological Office. The first earthquake had the magnitude of ML3.7 and the second earthquake had the magnitude of ML3.5. Many smaller earthquakes took place between this earthquakes. Most of them with the magnitude of 1.0 to 2.5. Earthquake activity is currently ongoing in this area at the moment. Earthquake activity started east of Grímsey Island around 00:04 UTC, 13.10.2012. The first earthquakes where smaller then 2.0 in magnitude.


The earthquake swarm on TFZ during the night. Copyright of this image belongs to Icelandic Meteorological Office.

This area of TFZ is well known for earthquake activity. During past few weeks it had several earthquake swarms around this location. More earthquakes should be expected in this area in next few hours to days. I do not know if any of this earthquake activity has been felt in Grímsey Island.

Blog post updated at 08:05 UTC.

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Earthquake swarms in Brennisteinsfjöll volcano and TFZ

Over the past few days there has been continued earthquake activity in Breinnisteinsfjöll volcano. The largest earthquake in this swarm had the magnitude of ML2.5. It is possible that this earthquake swarms have there orgin in SISZ. Rather then Breinnisteinsfjöll volcano. But at current time is hard to be sure on this detail.


Earthquake activity in Breinnisteinsfjöll volcano during the past few days. Copyright of this image belongs to Icelandic Meteorological Office.

Tjörnes Fracture Zone

Earthquake activity has also been taking place east of Grímsey Island. This earthquake activity has mostly been small. But this are earthquake swarm did not have any earthquake that was above 3.0 in magnitude.


Earthquake swarm on TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

The largest earthquake in this swarm had the magnitude of ML2.8. More earthquake activity should be expected in this area. As this is one of most active areas in Iceland when it comes to earthquake swarm.

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Magnitude 3.8 earthquake in Breinnisteinsfjöll volcano

Earthquake with the magnitude of 3.8 took place in Breinnisteinsfjöll volcano at 19:42 UTC. This earthquake was felt in Reykjavík and nearby area. Many aftershocks have followed this earthquake. Most of them are however below 2.0 in magnitude. There was also pre-earthquake activity before the magnitude 3.8 earthquake did take place. Most of those earthquakes where below 2.0 in magnitude. Last month an earthquake with the magnitude 4.3 took place in this same area. Earthquake activity is currently ongoing with smaller earthquakes for the time being.


Green star marks the place where the magnitude 3.8 earthquake took place. Copyright of this image belongs to Icelandic meteorological Office.

So far there is nothing to suggests that current earthquake activity is nothing but tectonic. But this area is a riftzone. So there are earthquake swarm often take place there without them being related to any volcano activity in this area. This earthquake swarm appears clearly on my geophone network in Iceland. I am going to continue to monitor this earthquake activity. As more strong earthquakes in this area can take place in the next few hours to days.

Icelandic news about this earthquake activity

Jarðskjálfti upp á 3,8 í Bláfjöllum (Rúv.is)
Jarðskjálftar við Bláfjöll (mbl.is)
Jarðskjálfti í Bláfjöllum (Vísir.is)
Skjálftinn var 3,8 stig (mbl.is)

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Earthquake swarm east of Grímsey Island.

This morning a earthquake swarm started east of Grímsey Island. This is activity in TFZ area that possibly has two active volcanoes (GVP information). This is however most likely just a normal earthquake activity taking place now in this area of Iceland. The largest earthquake in this earthquake swarm was a magnitude 3.1 earthquake that took place at 11:35 UTC.


Earthquake swarm on TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

This earthquake swarm might continue for the next few hours. With the possibility of more earthquakes reaching magnitude 3.0 or larger. But it is common for earthquakes swarms in this area to just stop over period of few hours. The largest earthquake in this earthquake swarm was not felt according to the news.

Icelandic news about this earthquake swarm

Jarðskjálfti norðan Grímseyjar (Rúv.is)
Jarðskjálftahrina við Grímsey (mbl.is)

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Magnitude 3.1 earthquake in Katla volcano this morning

Today at 08:26 UTC this morning a magnitude 3.1 earthquake took place in Katla volcano. There was minor pre-earthquake activity before the magnitude 3.1 earthquake took place, the depth of this earthquake was around 100 meters (0.1 km). There was also some minor aftershock activity following this earthquake. No change in harmonic tremor took place following this earthquake. So there is a good chance this was just part of normal autumn activity in Katla volcano. This earthquake activity did appear clearly on my geophone network. It can be viewed here on my geophone network web page.


The earthquake as it did appear on my geophone station in Skeiðflöt. This image is released under Creative Commons licence. See CC licence page for more details.


The earthquake as it did appear on my geophone station in Heklubyggð. This image is released under Creative Commons licence. See CC licence page for more details.


The location of the earthquake in Katla volcano. Copyright of this image belongs to Icelandic Meteorological Office.

More earthquakes like this should be expected in Katla volcano. But it is impossible to know if there is going to be an eruption in Katla volcano any time soon. But so far everything is quiet in Katla volcano. Besides occasional earthquake swarm that is taking place in Katla volcano.

Icelandic news about this earthquake activity

Jarðskjálfti í Kötlu – 3,2 að stærð (Rúv.is)
3,2 stiga skjálfti í Kötlu (mbl.is)
Snarpur skjálfti í Kötlu (Vísir.is)

Blog post updated at 19:34 UTC on 03.10.2012
Blog post updated at 05:45 UTC on 04.10.2012

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Earthquake activity east of Grímsey Island (TFZ). Possible fake earthquakes in Eyjafjallajökull volcano

At 03:03 UTC an earthquake with the early and unconfirmed magnitude of ML3.3 took place east of Grímsey Island. This earthquake did take place on TFZ. It is possible, but this earthquake might be the start of an earthquake swarm in this area. But that is not uncommon pattern for earthquakes in this area. But however it also happens that earthquakes like this one takes place. But then nothing more happens.


Earthquake activity in TFZ. The early magnitude ML3.3 earthquake is marked with a green star. Copyright of this image belongs to Icelandic Meteorological Office.

Eyjafjallajökull volcano

There has also been some earthquake activity in Eyjafjallajökull volcano during the night. This activity is possibly false due to weather or faulty SIL seismometer. The earthquake that have been detected so far have extremely low quality. But the increases the chance of them being false, rather then real events. It is not going to get known if this activity is real or not until it is reviewed by seismologist at Icelandic Meteorological Office.


The possible earthquake activity in Eyjafjallajökull volcano. This activity might be due to faulty hardware or weather, rather then real activity in Eyjafjallajökull volcano.Copyright of this image belongs to Icelandic Meteorological Office.

Eyjafjallajökull volcano has been quiet since it’s eruption in the year 2010. I do not expect that to change any time soon. Since it seem that Eyjafjallajökull volcano eruption cycle is around 150 to 500 year (theoretical maximum in my opinion). So I am not expecting anything to happen in Eyjafjallajökull volcano any time soon. If this earthquake activity is confirmed it is interesting. What might come out it is impossible to know for sure.

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Minor earthquake swarm in Katla volcano

Tonight around 22:30 UTC there was an minor earthquake swarm in Katla volcano. This earthquake swarm did last in about 20 minutes. After that the earthquake activity did drop back to normal background levels. This earthquake swarm is most likely part of normal autumn earthquake activity in Katla volcano. More earthquake swarms like this should be expected in Katla volcano during next few weeks.


Earthquake activity in Katla volcano this evening (28.09.2012). Copyright of this image belongs to Icelandic Meteorological Office.

What happens next is impossible to know. But I am not expecting anything special to happen in Katla volcano following this earthquake swarm. This earthquake swarm did appear clearly on my geophone at Skeiðflöt and Heklubyggð. The geophones can be viewed here.

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Minor earthquake swarm in Katla volcano

Normal autumn activity appears to be starting in Katla volcano. This earthquake activity is not something to be alarmed about. But worth keeping an eye on anyway.


The earthquake activity in Katla volcano during the past 48 hour period. Copyright of this image belongs to Icelandic Meteorological Office.

This is just normal autumn activity. As such it is not dangerous and does not mean anything. More earthquakes might happen in next few days to weeks.

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TFZ earthquake swarm update at 20:50 UTC

This is a short update for the earthquake swarm in TFZ at 20:50 UTC.

At 19:42 UTC on 20.09.2012 an earthquake with the magnitude of ML4.2 took place on TFZ. This earthquake swarm was most likely felt in Siglufjöður town, Dalvík town and possibly more places around the epicenter of this earthquake. This earthquake did also appear clearly on my geophone network in Iceland. Swarm of smaller earthquakes did follow this larger earthquake as before.


The epicenter of the latest magnitude ML4.2 earthquake in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.


The progress of the earthquake swarm during the past 48 hour period. This earthquake swarm happens in swarm, with drop in activity between them. Copyright of this image belongs to Icelandic Meteorological Office.


The earthquake swarm as it did appear on my Hvammstangi geophone station. This image is released under Creative Commons licence. Please see CC licence page for more details.


The earthquake swarm as it did appear on my Heklubyggð geophone station. This image is released under Creative Commons licence. Please see CC licence page for more details.

It is impossible to predict the progress and development of this earthquake swarm. But I expect this earthquake swarm to continue for the next few hours to days. It might last longer then few days. But only time is going to tell us what is going to happen next in this earthquake swarm. I am going to post new update on this earthquake swarm once I have had the time to check some of this data. But that might take few hours until I can do so. At the longest, not until tomorrow. Depending on IMO work on this earthquake swarm data. I am going to post new updates on this earthquake swarm soon as possible if anything major happens.

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Continued earthquake activity in TFZ

This morning (19.09.2012) at 04:53 UTC the earthquake swarm that has been ongoing in TFZ (Tjörnes Fracture Zone) started to intensify. But it was not until 07:55 UTC the first strong earthquake did happen. But then a magnitude 3.0 earthquake did take place about 20 km north-east of an town named Siglufjörður. The largest earthquakes have been felt in Siglufjörður, Ólafsfjörður and Sauðárkrókur and possibly more towns close to this area of activity on TFZ. The largest earthquake so far had the magnitude of ML4.3, other earthquakes had the magnitude 3.0, 3.4, 4.0 and 3.2. The depth of this earthquake swarm is from 17 km and up to 2 km or so. This area does not have any active volcanoes. But it highly active when it comes to earthquakes. But spreading in this area of Iceland is up to 50mm/year.


This image shows part of the Tjörnes Fracture Zone. It is from this science paper here. Copyright of this image belongs to Icelandic Meteorological Office/Hjorleifur Sveinbjornsson


Earthquake swarm at 15:10 UTC. As can be seen here on this image where the earthquake swarm is taking place. Copyright of this image belongs to Icelandic Meteorological Office.


The earthquake swarm at 16:15 UTC. This image has few new earthquakes that have taken place in this earthquake swarm since the picture from 15:10 UTC. Copyright of this image belongs to Icelandic Meteorological Office.


The earthquakes as they did appear on my Hvammstangi geophone. This image is released under Creative Commons Licence. Please see CC page fore more details.


The earthquakes as they did appear on my Heklubyggð geophone. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML3.0 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML3.0 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.3 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.3 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.3 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.0 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.0 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.


The magnitude ML4.0 earthquake on TFZ. This image is released under Creative Commons Licence. Please see CC page fore more details.

The last earthquake was at 16:52 UTC. That was magnitude 2.0 earthquake. But it is hard to know if this earthquake swarm is over or not. I am going update this blog post or make a new one if any new major development take place in TFZ. Larger earthquakes in this area cannot be ruled out at this time.

Icelandic news about this earthquake

Harðir jarðskjálftar fyrir norðan (mbl.is)
Skjálftahrina fyrir norðan (Vísir.is)
Jarðskjálfti 4,3 í Eyjafjarðarál (Rúv.is)
Enn skelfur undan Tröllaskaga (Rúv.is)