Category: TFZ

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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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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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Earthquake activity drops in TFZ

During the past few hours earthquake activity in TFZ has dropped. This is not unusual. As earthquake activity in this area happens in swarms. Last earthquake swarm in this area where in the years 1996 and 2004. Those earthquake swarm lasted for several days and made several earthquakes with the magnitude 4. It is impossible to know how long activity is going last in this area. But since it has been ongoing for better part of current week (week 38). It might well be this activity is already over. But only time is going to tell what happens next. In current earthquake swarm. More then 500 earthquakes have been recorded so far.


The area of activity in TFZ. Stars mark earthquakes that are larger then magnitude 4 in size. But red dots show other earthquakes. The arrows show the fault movements in this area. It is from this news here on IMO web page. Copyright of this image belongs to Icelandic Meteorological Office.


The earthquake swarm as it looks during the past 48 hours. Copyright of this image belongs to Icelandic Meteorological Office.


The earthquakes on IMO tracker. It shows the magnitude of most of the earthquakes that have taken place during past 48 hours. Copyright of this image belongs to Icelandic Meteorological Office.

As sad before. It is impossible to know what happens next in this earthquake swarm. But it might well be that it is over by now. Only time is going to tell us what happens next in this. Chance of an larger earthquake taking place in this area remains high.

Almannavarnir announcement (Icelandic Civil Protection System)

Jarðskjálftahrina úti fyrir Norðurlandi (Almannavarnir.is, Icelandic)

Icelandic news about this earthquake swarm

Jarðskjálftar í Eyjafjarðarál (Icelandic, vedur.is)
Talsverð jarðskjálftavirkni á Norðurlandi (Icelandic, Vísir.is)
Fjórir skjálftar yfir 4 að stærð (Icelandic, mbl.is)
Íbúar geri ráðstafanir til að draga úr tjóni (Icelandic, mbl.is)

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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)

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Earthquake swarm in TFZ

Yesterday (16.09.2012) an earthquake swarm did start in TFZ (Tjörnes Fracture Zone). The largest earthquakes in this swarm so far got the magnitude of 3.1 that took place at 11:07. The second earthquake took place at 14:13 UTC and had the magnitude of 3.4. This earthquake activity is located in an non-volcanic area. So this is nothing but tectonic activity. It is difficult to know for how long this activity is going to last. But it can be anything from two days and up to several days.


Current earthquake activity in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

This area might have more earthquakes that are above 3.0 in magnitude. But that is in no way certain that is going to happen. The largest earthquakes appear on my geophone network. Not all the stations. Just the one located in Hvammstangi.

Icelandic news about this activity

Skjálftar norður af Eyjafirði (Rúv.is, Icelandic)
Jarðskjálfti í Eyjafjarðarál (Rúv.is, Icelandic)
Skjálftahrina við Siglufjörð (Vísir.is, Icelandic)
Jarðskjálftar í Eyjafjarðarál (mbl.is, Icelandic)

Blog post updated at 16:58 UTC on 17.09.2012

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Earthquake swarm on TFZ and in Þeistareykir volcano

This is going to be short blog post.

Earthquake east of Grímsey Island

Earthquake with the magnitude of ML3.5 (estimate) did take place at 19:48 UTC. This is normal tectonic activity for this area. But this area of Iceland has the most earthquake activity most of the year.


Earthquake activity in TFZ. Copyright of this picture belongs to Iceland Meteorological Office.

Þeistareykjabunga volcano

It was noticed by a reader of this blog that Þeistareykjabunga volcano was having few earthquakes. Þeistareykjabunga volcano last erupted in the year 900 BC (+- 100 years). This earthquake swarm was small. Mostly earthquakes with the magnitude of ML0.5 to ML1.0. The focal depth of this earthquake swarm was around 5 km. So this in all, is most likely an tectonic earthquake swarm. Rather then volcanic. Þeistareykjabunga volcano is an active volcano. But at current time I do not think anything has changed in that volcano at present time.


Þeistareykjabunga volcano is located north of Krafla volcano. Copyright of this picture belongs to Iceland Meteorological Office.

I do not expect anything more to happen in Þeistareykjarbunga volcano. But if there are changes, they won’t go unnoticed.

Thanks to Mafl for the tip on Þeistareykjabunga volcano.

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Minor earthquake swarms in Iceland

It has been quiet in Iceland during the past few weeks. Besides activity in Katla volcano and Kolbeinsey ridge. Nothing of interest has been going on in Iceland. Here is however the overview of activity in Iceland during the past few hours.

Kolbeinsey Ridge

Some minor earthquake activity has been taking place in Kolbeinsey Ridge during the past few hours. This earthquake swarm is small in nature, with largest earthquakes reaching the magnitude 2.4. Otherwise it remains quiet in this area.


Earthquake activity in Kolbeinsey Ridge. Just north of Grímsey Island. Copyright of this image belongs to Iceland Meteorological Office.

Kolbeinsey ridge has seen some activity during past few weeks. But it might just be normal tectonic earthquakes taking place. So far nothing suggest any volcanism nature of this earthquake activity.

Krýsuvík volcano

During the past few hours. Krýsuvík volcano did see some earthquake activity. This activity is most likely to be tectonic in nature. As Reykjanes peninsula has frequent earthquake swarm that are tectonic in nature.


Earthquake swarm on Reykjanes. It is located within Krýsuvík volcano. This was small earthquake swarm. Copyright of this image belongs to Iceland Meteorological Office.

It remains rather quiet on Reykjanes besides this minor earthquake swarm today.

Katla volcano

After rather interesting activity during the past few weeks. It seems that Katla volcano is slowing down in earthquake activity. For now at least. But it is impossible to know for sure if current quiet sense is going to continue in Katla volcano.


Earthquake activity in Katla volcano during past few days. The activity is mostly concentrated into Katla volcano caldera. Copyright of this image belongs to Iceland Meteorological Office.

Besides this top of the activity. All is quiet in Iceland. Both in volcanoes and earthquakes. That might however change at any time without warning. It happens often in Iceland. I also want to remind people of my geophone web page. Where earthquakes can sometimes be seen soon after they have taken place.

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Minor earthquake activity in Iceland

During the past few weeks it has been quiet in Iceland. Really quiet, with almost nothing going on. It is still like that to some extent. So this is just a short overview of the small activity that has been taking place in Iceland during the past 48 hours or so.


The earthquake activity in Iceland during the past 48 hours. Copyright of this image belongs to Iceland Met Office.

The most activity in the last 48 hours have been on the Reykjanes and on TFZ. But there was an small earthquake swarm in each area. With earthquakes that did not get over ML2.5 in size so far. Two earthquakes where in Askja volcano. One in Grímsfjall volcano fissure system (maybe in Þórðarhyrna volcano).


Earthquake west of Hekla volcano, in the SISZ. This picture is released under Creative Common Licencee. See the licence page for more detail.

Katla volcano

During this winter. Katla volcano has been quiet. This is somewhat normal, as more snow means more ice-mass on top of the volcano. But now that has started to melt a little and that means less ice-mass on top of the volcano. That could mean more activity in Katla volcnao during the next few weeks. So far however the activity remains small and there are no special earthquakes to report.


Earthquake activity in Katla volcano, on this picture earthquake activity west of Hekla volcano can also been seen here. Copyright of this image belongs to Iceland Met Office.

The earthquakes west of Hekla volcano belong to the SISZ fault area. Not Hekla volcano it self. What is also interesting is the earthquake activity in south part of Katla volcano. In area outside of the glacier. This are small earthquakes, that do not appear on my geophone. Even if they are close to it. I am unsure what this means for the future. But it is worth keeping an eye on it.

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Earthquakes in north and south Iceland [Updated]

This evening has been busy in Iceland. There was an ML3.5 earthquake just outside an area called Gjögurtá (part of TFZ). Followed by an ML3.2 aftershock. Earthquake activity seems to have stopped there for the moment. This took place at 22:06 UTC on 29.02.2012. The largest earthquake was felt over an large area that was closest to its location.


The location of the earthquake in the TFZ. Copyright of this picture belongs to IMO.

At 00:29 UTC on 01.03.2012 there was an earthquake on the Reykjanes. It happened in an mountain called Helgafell. Early results suggest that this earthquake had the size of ML3.2. It was felt over an wide area in south Iceland. Aftershocks are currently taking place, and more large earthquakes in this area cannot be ruled out at the moment.


The earthquake location on the Reykjanes. Copyright of this picture belongs to IMO.

There is an chance for more earthquakes in Reykjanes. As earthquake swarms in this area of Iceland can often be tense and make many earthquakes that have magnitude 3.0 and stronger.

This earthquake activity appears clearly on my geophones in Iceland. They can be viewed here and are updated every 5 min.

Update 1: More strong earthquake activity is taking place on the Reykjanes at this moment. The largest earthquake so far is ML3.9 according to the automatic data from IMO.

Update 2: Here is the image from Iceland Met Office of the area where this earthquake activity is taking place.


The current earthquake activity on the Reykjanes. Copyright of this picture belongs to IMO.

Update 3: The size of the second earthquake has been upgraded to ML4.2. Some minor damage has already been reported according to new from Rúv.

Blog post updated at 01:14 UTC on 01.03.2012.
Blog post updated at 01:39 UTC on 01.03.2012.
Blog post updated at 01:52 UTC on 01.03.2012.

Icelandi News about the earthquake in north Iceland. All news are in Icelandic.

Jarðskjálfti upp á 3,5 út af Gjögurtá (mbl.is)
Snarpir skjálftar fyrir norðan (Vísir.is)
Skjálfti út af Eyjafirði (Rúv.is)

News about the earthquake on the Reykjanes. All news are in Icelandic.

Skjálftakippur á höfuðborgarsvæðinu (Rúv.is)
Jarðskjálfti fannst vel á höfuðborgarsvæðinu (Vísir.is)
Jarðskjálfti við Helgafell (mbl.is)