Magnitude 4.8 earthquake deep on the Reykjanes Ridge

During the night there was an earthquake deep on the Reykjanes ridge. This earthquake had the magnitude of 4.8 according to automatic result from EMSC.

308812.regional.svd.20.03.2013
The earthquake on the Reykjanes ridge. Copyright of this image belongs to EMSC.

Due to earthquakes location there is not a lot of details on it. But this location on the Reykjanes ridge has been seeing some activity in the past few months. This might well just be normal tectonic activity for this area. More information on this earthquake can be found here.

Minor earthquake swarm on Reykjanes Ridge

A minor earthquake swarm started on Reykjanes Ridge today. So far no earthquake has had the magnitude 3.0 or larger. The largest earthquake so far has had the magnitude 2.8. The depth of this earthquake swarm is around 4 to 7 km.

130206_1850
The earthquake swarm on the Reykjanes Ridge at 18:50 UTC. Copyright of this image belongs to Icelandic Meteorological Office.

It is hard to know what happens with this earthquake swarm. But if any major changes happens with this earthquake swarm. I am going to post a blog post about it soon as possible.

Earthquakes deep on the Reykjanes Ridge

Yesterday (20.01.2013) there where few medium sized earthquakes deep on the Reykjanes Ridge. This earthquakes where far off the coast of Iceland (around 1340 km from Reykjavík). So this earthquake swarm is just being noticed on instruments. What is going on there is impossible to know. The largest earthquake in this swarm is a magnitude Mb5.2 earthquake that did happen at 21:40 UTC. Earlier and earthquakes that did follow this earthquake had the magnitude from Mb4.7 to Mb5.0. But any smaller earthquakes are unlikely to be detected at this distance from any seismometer network in Europe or America.


Location of the largest earthquake in this swarm. A magnitude 5.2 earthquake. Copyright of this image belongs to EMSC.

More earthquake activity might take place on this location. But it is hard to know due to lack of data. But it is worth keeping an eye on it. As things remain quiet in Iceland at the moment.

Blog post updated at 00:37 UTC on 21.01.2013.

Earthquake swarm on Reykjanes Ridge last night (16.09.2012)

Last night there was an earthquake swarm on Reykjanes Ridge. Possibly on one of the volcanoes that are in this area of Iceland. The earthquake swarm lasted for several hours. Strongest earthquakes in this swarm had the magnitude of 3.5. With the depth from 23 km and up to 0.3 km. Strongest earthquakes in this swarm where visible on my geophone network.


The earthquake swarm on the Reykjanes Ridge. Copyright of this image belongs to Icelandic Meteorological Office.

Last earthquake swarm in this area was on 8. February 2012. There was also earthquake activity deep on the Reykjanes Ridge. With two earthquakes that did get the magnitude 4.4 (EMSC) at 12:51 UTC. The second earthquake took place at 14:30 UTC and had the magnitude of 4.4 (EMSC). This earthquake activity is far enough from land that only the largest earthquakes are detected.

But there seems to be a lot of earthquake activity both south and north of Iceland (Jan Mayen earthquake activity). But this not connected activity as such. But it is known that activity on Reykjanes Ridge happens in jumps. It is an question if such time has come that an new activity episode is about to start on the Reykjanes Ridge. But last major episode in activity on the Reykjanes Ridge ended about 671 years ago. But there is one eruption documented off the coast in the year 1926 according to Global Volcanism Program. That activity did last for 4 days or so.

I am not sure what is going to happen next on the Reykjanes Ridge. But I am going to report it best to my ability. With the best information that I can get when the time comes.

Icelandic news about this earthquake activity

34 skjálftar frá miðnætti (mbl.is, Icelandic)

Blog post updated at 02:47 UTC on 17.09.2012

Earthquakes deep south on the Reykjanes Ridge [Updated]

During last night there has been some earthquake activity deep south on Reykjanes Ridge. This earthquake activity is far from the south coast of Iceland so it has not been noticed by any people. It has only appeared on seismometers. The web page of EMSC has shows the current earthquake activity started at 00:21 UTC with two earthquakes. The largest earthquake recorded in following hours had the magnitude of Mb5.3 according to EMSC web page. But that is automatic size estimate and is subject to a change.


The location of the earthquake deep south on Reykjanes Ridge. Copyright of this image belongs to EMSC.

There most likely have been more earthquakes in this area then are registered by seismometer networks. It seems that earthquake activity in this area has quieted down again. For now at least. But this area is subject to strong earthquake swarms on regular basic.

Blog post updated at 21:33 UTC on 15.08.2012.

Earthquakes in Katla volcano. Earthquake swarm continues close to Herðubreið. Other earthquake activity

This morning there was a short earthquake swarm in Katla volcano caldera. This earthquake looks like a minor dike intrusion did take place this morning. Current series of events did start on 28. April 2012. With a small earthquake event and a small glacier flood that did follow it. Along with harmonic tremors coming from the glacier flood and possibly Katla volcano caldera (hydro-thermal activity boiling or something of that nature). I do not yet know if there was any glacier flood following the event this morning. But so far there is nothing that suggests a small glacier flood did take place following the earthquake swarm this morning.

The earthquake swarm this morning took place on an location that did erupt on 8 and 9th of July 2011. So it is clear the area that erupted last year is picking up activity again. But there was an drop in activity from end of November 2011 until end of April 2012.


Earthquake activity in Katla volcano this morning. Copyright of this picture belongs to Icelandic Meteorological Office.

This earthquake activity did appear well on my geophone at Skeiðflöt farm.


Earthquake activity in Katla volcano caldera this morning on my Skeiðflöt geophone. There is a lot of noise on this geophone. But earthquake activity can still be seen on this. The earthquakes are marked by red (some noise is also marked by red). This picture is released under Creative Commons Licence. See CC Licence page for more details.

It is clear that Katla volcano seems to be warming up to an eruption. But it is impossible to know when such eruption might happen, or how big it is going to be.

Herðubreið

Earthquake activity continues south-west of Herðubreið. But almost all of the earthquakes have been less then ML2.0 in magnitude. Earthquake activity has been slowing down all day. At the moment, it appears this earthquake swarm is close to being over.


The earthquake activity close to Herðubreið mountain. Copyright of this picture belongs to Icelandic Meteorological Office.

This area is well known for for earthquake activity. So this is not something that is new in this area.

Reykjanes Ridge

According to EMSC and USGS there have been several earthquakes with the magnitude of Mb4.5 to Mb4.8 on the Reykjanes Ridge. Earthquake activity is common on the Reykjanes Ridge. But because of the location and depth (around 2km) it is impossible to know if there any volcano eruption taking place at this location. It might well be, or not.

Kolbeinsey Island

Over the past weeks there has been some earthquake activity close to or in Kolbeinsey Island. The largest earthquakes have had the magnitude around ML3.0, with some underestimates due to distance from the SIL network. At this moment it is impossible to know if this earthquake activity is related to possible eruption activity. But it believed that an eruption (or dike intrusion) took place on Kolbeinsey Ridge in the year 1999. It started off with a large earthquake swarm.

Overview of earthquake activity in Iceland past few weeks

During the past few weeks it has been quiet in Iceland. With few earthquakes. March for instance was rather quiet month. In Week 17 there was more activity in Katla volcano, then the weeks before.

There have been several small earthquake swarms taking place in Iceland during past few weeks. Most noticeable was off the coast of Flatey. That is on TFZ earthquake zone. Also there was a noticeable earthquake swarm in Hengill volcano due to water pumping activity. There has also been earthquake activity on the Reykjanes ridge. Where the largest earthquake had the size of ML3.3.

Other then this minor earthquake activity. It is has been rather quiet in Iceland for several weeks now. This does happen in Iceland. But even so, there is always something interesting going on when it comes to earthquake activity in Iceland.

Short earthquake swarm on Reykjanes Ridge

This morning there was an short earthquake swarm on the Reykjanes Ridge. This earthquake swarm only lasted for about 1 hour. The largest earthquake had the size around ML3.1 (automatic size estimate).


The earthquake swarm on the Reykjanes Ridge this morning. Copyright of this picture belongs to Iceland Meteorological Office.

There is still a risk of this earthquake swarm is going to resume at any point for the moment. But it still might just be over. It is hard to know for sure at current time. The strongest earthquake was visible on my geophones in Iceland. The web page can be viewed here.

Icelandic news about this short earthquake swarm

Skjálftahrina á Reykjaneshrygg (mbl.is)

Strong earthquake in Japan, small earthquake swarm on Reykjanes Ridge in Iceland and more

Yesterday (14.03.2012) at 09:08 UTC there was an strong earthquake in Japan. The size of this earthquake was Mw6.9 and it had the depth of 10 km. Local tsunami warning was given out for the area closest to the epicenter of the earthquake. Aftershock activity has been ongoing after the main earthquake. The largest aftershock so far had the size Mw6.0. More details on the earthquake in Japan can be found here at EMSC web page.


Regional view of the earthquake in Japan yesterday morning. Copyright of this image belongs to EMSC.


Local view of this earthquake. It appears to have been in an subduction mountain, or close to it. Copyright of this image belongs to EMSC.

Iceland

Currently there is an earthquake swarm ongoing on the Reykjanes Ridge off the coast of Iceland. So far the strongest earthquake has reached the size of ML2.7. The depth is about 7 – 16 km. There is an slight chance that his might be an dike intrusion taking place on the Reykjanes Ridge. But this also might just be normal fault movement in the area. For the moment. There is no way to know for sure exactly why this earthquake swarm is taking place.


Reykjanes Ridge earthquake swarm as it is at 00:35 UTC. Copyright of this image belongs to Iceland Met Office.

South Norway

An minor earthquake took place in south Norway at 19:22 UTC. The size of this earthquake was ML3.5 according to EMSC. With the depth of 10 km. This earthquake was clearly felt in Norway according to EMSC and news reports of this earthquake. More details on this earthquake can be found here, on EMSC web page.

The regional view of the earthquake in south Norway. Copyright of this image belongs to EMSC.


Local view of the earthquake. It can clearly be seen here how close it was to several towns in south Norway. Copyright of this image belongs to EMSC.

This earthquake was clearly felt in Norway due the old crust that it took place it. But older crust conducts earthquakes better then new crust. Like the one that can be found in Iceland. That is due to lack of faults in it and the fact it is more dense with sediments then new crust. Earthquake in this area should be expected every 5 to 20 years or so. As there are old fault lines in this area, they sometimes break and create a earthquake.

Norwegian news about this earthquake.

Kanskje noen glass har falt ned fra bordet
Jordskjelv i Rogaland i kveld

New Britain region

Today at 21:13 UTC there was an Mw6.4 earthquake in New Britain region. The depth of this earthquake was 80 km according to EMSC. I do not know if this earthquake was felt or not. It at least has not been reported yet.


Regional view of the earthquake from EMSC. Copyright of this image belongs to EMSC.


Local view of the earthquake from ESMC. Copyright of this image belongs to EMSC.

More information about this earthquake can be found here, on EMSC web page.

Other

I am sorry for late post. I was flying back to Iceland today. It took awhile. I also had to do other things this evening before I could write about the most recent activity yesterday. This is going also going to happen later when I move back to Denmark. But I am going to post more details on that later.

Blog post updated at 12:11 UTC on 15.03.2012. Location of the earthquake in Norway was fixed.

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)