Information on the magnitude 5.5 earthquake in TFZ

This is a short blog post about the earthquake swarm in Tjörnes Fraction Zone.

The largest earthquake so far is a magnitude 5.5. The largest aftershocks so far are magnitude 4.4 that took place at 01:14 UTC and 4.7 that took place at 08:55 UTC this morning. This earthquake swarm is taking place on a complex fault area that is highly active. There is also big question what effect this earthquake swarm is going to have on other faults in the area. There is a risk that this earthquake swarm is going to start other earthquake swarms in nearby faults. Uncertainty level has been declared for area from Sauðárkrókur to Raufarhöfn at least. This is the largest earthquake in this area since the year 2002 and 2005. But both this years there was a magnitude 5.0 earthquakes in this area.

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The earthquake activity in TFZ. Green stars are earthquakes that are larger then magnitude 3.0. Copyright of this image belongs to Icelandic Meteorological Office.

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This trace shows how dense this earthquake swarm has been. Copyright of this image belongs to Icelandic Meteorological Office.

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The earthquake is appearing clearly on my geophone network. This is Böðvarshólar geophone station. This image is released under Creative Commons licence. Please see the CC Licence page for more details.

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The largest earthquakes as they did appear on Heklubyggð geophone station. This image is released under Creative Commons licence. Please see the CC Licence page for more details.

There have been over 500 earthquake recorded since this earthquake swarm did start. It is impossible to know for sure when this earthquake swarm is going to stop, or if it is going to pick up again. But the earthquake swarm is already starting to shown signs of dropping activity. But that might change again if there is new larger earthquake in this area, or swarm of larger earthquake.

I am going to post update of anything major happens in this earthquake swarm. It is possible to monitor the current status of this earthquake swarm here on my geophone web page.

Blog post updated at 15:23 UTC on 02.04.2013.
Blog post updated at 16:14 UTC on 02.04.2013.
Blog post updated at 16:26 UTC on 02.04.2013.

Note on login issue

I was made aware of login issue today. But I had to install a anti-spam bot system due to the volume of spam bots that where registering on my web site. This created unknown to me issue for already registered users. I have fixed that issue now. So login in should work for everyone without a issue now. If it does not. Please email me and I am going to do my best to resolve the issue.

Image of the TFZ earthquake

Here are the images of the earthquake that took place at 01:00 UTC in TFZ. I do not have correct magnitude for this earthquakes yet. So it is missing at the moment.

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The earthquake at Böðvarshólar geophone station. This image is relased under Creative Common licence. Please see the CC Licence page for more details.

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The earthquake at Heklubyggð geophone station. This image is relased under Creative Common licence. Please see the CC Licence page for more details.

Earthquake swarm east of Grímsey island (TFZ)

Today at 05:25 UTC a earthquake swarm started east of Grímsey island. But this island is located in the Tjörnes Fracture Zone. The largest earthquake today is a magnitude 2.8. No larger earthquakes have taken place so far.

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

Earthquake activity is common in this area of Iceland so this is nothing unusual. This earthquake swarm is not connected to any volcano activity that I know of. If anything major happens. I am going to write a blog post about it soon as I can do so.

Deep earthquakes in Askja and Kverkfjöll volcanoes

This is a update for both Askja and Kverkfjöll volcanoes. Since they both had deep earthquakes today. None of this earthquakes where larger then magnitude 1.0. There depth was around 22 to 24 km inside the volcanoes them self.

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Earthquakes in Kverkfjöll and Askja volcanoes. There depth was around 22 to 25 km. Copyright of this image belongs to Icelandic Meteorological Office.

GVP Kverkfjöll volcano profile. GVP Askja volcano profile.

It is impossible to know for sure what this means in terms of future activity. But this are both active volcanoes and should be treated as such.

Magnitude 3.5 earthquake south of Langjökull glacier

Today at 17:24 UTC a magnitude 3.5 earthquake took place south of Langjökull glacier. This earthquake had pre-earthquakes with the magnitudes from 2.1 and up 2.8. There where also several smaller earthquakes at the same location. This earthquake did appear clearly on my geophones in south and north Iceland. My webicorders can be viewed here.

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Langjökull earthquake activity today. Copyright of this picture belongs to Icelandic Meteorological Office.

This appears to be normal tectonic earthquake swarm that are common for this area. They are not related to any volcano activity at present time. But this area often has earthquake activity with it being connected to any volcano activity. The earthquake swarm is continuing when this blog post is published. This earthquake swarm might stop at any time, or pick up at any time without a warning. If that happens. I am going to write a new blog post about it soon as possible.

Magnitude 4.4 earthquake north of Kolbeinsey Island

Today at 17:32 UTC there was a magnitude 4.4 earthquake north of Kolbeinsey Island. I do not know if this earthquake was tectonic or volcanic in nature. I do know that there where several aftershocks following this earthquake. Since I did register them on my geophone in north Iceland. The geophone web site can be viewed here. More information about the earthquake can be found here, on EMSC web page.

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Regional view of the area where the earthquake took place. Copyright of this image belongs to EMSC.

Icelandic Meteorological Office did also detected many of this earthquakes that took place there. But detection from this location is difficult due to distance from the SIL network.

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The earthquake swarm location according to Icelandic Meteorological Office. Copyright of this image belongs to Icelandic Meteorological Office.

For now this is just a earthquake swarm and nothing else. Regardless of what happens later. Earthquake activity has been common in this area of the rift zone for several months now. I do not know why that is. The ocean depth in this area is around 3 to 4 km where it is the deepest. So if an eruption takes place there it is not going to be noticed due to the depth of the ocean.

Deep earthquakes in Askja volcano

Today (26.03.2013) at 08:09 UTC there where three deep earthquakes in Askja volcano. The most depth of this earthquake swarm was 25.5 km. None of the earthquake had the magnitude above 2.5. The strongest earthquake had the magnitude 2.1 with the depth of 20.4 km

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Earthquakes in Askja volcano. Askja is located to the north of Vatnajökull glacier and the lake is round in shape on this map. Marked by the orange dots on it. Copyright of this image belongs to Icelandic Meteorological Office.

This activity is part of an progress that started in Askja volcano back in the year 2010. So far this has not lead to any eruption. But it has created some odd changes. Along one was that Askja lake was ice free last year (winter 2012). The reasons for that are still not known to me.

Blog post updated at 16:32 UTC on 26.03.2013.