Category: Swarm

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Glacier flood has started from west Skaftárketill cauldron in Vatnajökull glacier

Yesterday an glacier flood started form west Skaftárketill cauldron. But that is an hydro-thermal area inside Hamarinn volcano (Bárðarbunga volcano system). The glacier flood is expected to be small. Last year in July there was also an glacier flood from this area of Vatnajökull glacier. But that was due to minor eruption in this area (it was poorly documented by scientists. I do not know why that is). But now it is melt-water from hydro-thermal area that is causing this glacier flood.

But glacier floods like this happen every 1 to 3 years from this area. Following this glacier flood an swarm of glacier-quakes have been detected in this part of Vatnajökull glacier. Flood in western Skaftárkatli might trigger a glacier flood in the eastern skaftárkatli cauldron. But it is not known if that is actually going to happen this time. It is not expected that current glacier flood is going to be a large one. But there is an risk of Hydrogen sulfide poisoning if people are close the glacier river during the glacier flood. So it is not recommend to go close to the glacier river due to this risk. The glacier flood is expected to appear from under Vatnajökull glacier in the next 5 to 6 hours. It is expected to last around 2 to 3 days at most.


Glacier quakes in Vatnajökull glacier following this glacier flood. This glacier quakes are not strong and do not show up on automatic SIL system. Copyright of this picture belongs to Icelandic Meteorological Office.


Glacier quake activity as it appears on SIL seismometers around Vatnajökull glacier. Copyright of this picture belongs to Icelandic Meteorological Office.


Glacier quake activity as it appears on SIL seismometers around Vatnajökull glacier. Copyright of this picture belongs to Icelandic Meteorological Office.


Glacier quake activity as it appears on SIL seismometers around Vatnajökull glacier. Copyright of this picture belongs to Icelandic Meteorological Office.


Click on this image for full size. This plot here shows output from several SIL stations. This image was released by Icelandic Meteorological Office today. Copyright of this picture belongs to Icelandic Meteorological Office.

It is believed that sometimes following this type of glacier floods from this area in Vatnajökull glacier there are small eruptions, or steam events as the pressure on the hydro-thermal system drops . That in turns allows for some magma movement that is powering the hydro-thermal system in this area of Vatnajökull glacier. It is impossible to know for sure if that is going to happen now. But it is good idea to keep an eye-out for such events taking place in Hamarinn volcano. Given the minor eruption that took place there last year.

Here is an comparison of the events that took place last year compared to the events that are currently taking place in Hamarinn volcano.


Harmonic tremor subsiding from Hamarinn volcano on 13. July 2011. The following glacier flood appears clearly on this tremor plot from Icelandic Meteorological Office. Copyright of this picture belongs to Icelandic Meteorological Office.

I was seeing activity to November 2011 after the activity in July 2011.


One of the last harmonic tremor activity that I did see in Hamarinn volcano during the year 2011. But this took place on 7. November 2011. After this point it did go quiet. Copyright of this picture belongs to Icelandic Meteorological Office.

I do not expect any volcano eruption in Hamarinn volcano at this point. But such things are impossible to know for sure. As Hamarinn volcano has not been studied in details until after the year 2011 eruption.

Icelandic news about this glacier flood

Hlaup hafið í Skaftá (Rúv.is)
Verður væntanlega ekki mikið hlaup (Rúv.is)
Hlaup að hefjast í Skaftá (Vísir.is)
Aldrei verið jafnfljótir að sjá hlaupið (Vísir.is)
Skaftárhlaup hafið (mbl.is)

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New earthquake swarm in Katla volcano

This morning at 07:03 UTC on 21. August 2012 an earthquake swarm started in Katla volcano. This earthquake swarm lasted for few minutes with the last earthquake taking place at 07:50 UTC. No harmonic tremor was detected following this earthquake swarm in Katla volcano. Update 1: The largest earthquake in this earthquake swarm had the magnitude of 2.6 at the depth of 0.1 km.


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

It is impossible to know for sure what this activity means. But this might just be normal autumn activity in Katla volcano. I am expecting more earthquake activity in Katla volcano in next few days to weeks.

Icelandic news about this earthquake activity

Skjálfti í Mýrdalsjökli (Rúv.is, Icelandic)
Jarðskjálfti upp á 3,1 stig í Mýrdalsjökli (Vísir.is, Icelandic)
3,1 stigs skjálfti í Mýrdalsjökli (mbl.is, Icelandic)

Blog post updated at 15:18 UTC on 21.08.2012. I have not yet fully recovered from the heat wave. I forgot the important information about this swarm. They have now been added.

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Earthquake swarm in progress in Krýsuvík volcano

Today (18.08.2012) at 15:52 UTC an earthquake swarm did start in Krýsuvík volcano. So far this swarm is not big. With the largest earthquake having magnitude 1.8 according to automatic size. It is impossible to know at this point if this earthquake swarm is going to be strong, or has just ended. So far earthquake activity continues with minor earthquakes.


The earthquake swarm in Krýsuvík volcano. Copyright of this image belongs to Icelandic Meteorological Office.

If the earthquake activity picks up. I am going to do my best to update this blog. But I am on limited 3G internet connection. So it might be a while until update takes place.

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Earthquake in Katla volcano today (17.08.2012)

Today at 15:48 UTC there was an magnitude 3.8, at the depth of 0.1 km in Katla volcano. This earthquake took place on the caldera rim in Katla volcano. No major harmonic tremor was detected following this earthquake. However some harmonic tremor was detected. But it was minor. This might have been hydro-thermal-activity or magma on the move. It is impossible to know for sure what is the case now. This earthquake did appear clearly on my geophone network. Mostly on the geophone station at Skeiðflöt and Heklubyggð.


The location of the earthquake in Katla volcano. It was located on the edge of Katla volcano caldera. Copyright of this image belongs to Iceland Meteorological Office.


Influence map of todays ML3.8 earthquake. This suggests that it was not felt in nearby populated areas. Copyright of this image belongs to Iceland Meteorological Office.


Tremor plot that clearly shows the earthquake of today. The spikes are the earthquakes that have been taking place in Katla volcano or close by areas. This is Alftagrof SIL station. Copyright of this image belongs to Iceland Meteorological Office.


This tremor plot shows some minor harmonic tremor following the earthquake in Katla volcano. The spikes show the earthquake from Katla volcano and areas close by. This is Austmannsbunga SIL station. Copyright of this image belongs to Iceland Meteorological Office.

It is impossible to know what this means exactly. But Katla volcano has been quiet since around middle of July. It remains to be seen if earthquake activity is picking up again or if this was just an single event.

Icelandic news about this earthquake

Jarðskjálfti í Mýrdalsjökli (Rúv.is, Icelandic)
Jarðskjálfti í Mýrdalsjökli (Vísir.is, Icelandic)
Jörð skalf við Austmannsbungu (mbl.is, Icelandic)

Blog post updated at 18.08.2012 at 11:51 UTC. Blog post title fixed for the future.

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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.

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Minor earthquake swarm in Brennisteinsfjöll volcano system

When I was moving there was an small earthquake in Brennisteinsfjöll volcano. Because I was moving I was unable to track this earthquake swarm properly. But the largest earthquake was around ML1.5 from what I can remember. The earthquakes had the depth of at least 2 km. But I am not sure what the exact depth is. But I have not yet looked at the reviewed data on this earthquake swarm.


The earthquake swarm in south-west part of Brennisteinsfjöll volcano. Copyright of this picture belongs to Iceland Meteorological Office.

There has not been a lot of activity in Iceland during all summer. So I have not had lot to write about. But that might change without any warning. As is common in Iceland.

I did also move on 7th of August to a new town in Denmark. That means I am out of ADSL connection until 24th of August. So this blog is going to suffer from lack of updates until I am properly connected to the internet.

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Earthquake swarm in SISZ this morning (31.07.2012)

This morning there was an earthquake swarm in SISZ. This earthquake swarm was located just south of Hveragerði and Selfoss town. The largest earthquake in this earthquake swarm had the magnitude of ML1.3. Most of the other earthquake where less the magnitude 1.0 in size. Focal depth for this earthquake swarm was 5 to 6 km. Total of 30 or so earthquakes where recorded in this earthquake swarm. This earthquake swarm is in continued activity in this area. But SISZ often has frequent smaller earthquake swarms.


The area of earthquake activity in SISZ this morning (31.07.2012). Copyright of this image belongs to Iceland Meteorological Office.

This doesn’t mean anything special. But SISZ (South Icelandic Seismic Zone) is always at risk having large earthquakes. But based on how short it was since last one took place (May 2008). It is unlikely that is going to happen now.

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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 swarm in Katla volcano

This Sunday is not quiet when it comes to earthquake activity in Iceland. Earlier today a small earthquake swarm started in Katla volcano. The largest earthquake in this swarm had the magnitude 2.3 according to the automatic SIL system. The largest earthquake did appear clearly on Skeiðflöt and Heklubyggð geophone stations. But Skeiðflöt geophone station is closest to the area where this earthquake swarm was taking place.


Earthquake swarm in Katla volcano. Copyright of this picture belongs to Iceland Meteorological Office.


The earthquake trace on Skeiðflöt geophone station. This is filtered at 1Hz. I have not located this earthquake trace (no P and S wave markers). This image is released under Creative Commons Licence. Please see CC Licence page for more details.


The earthquake trace from Heklubyggð geophone station. This is filtered at 1Hz. I have not located this earthquake trace (no P and S wave markers). This image is released under Creative Commons Licence. Please see CC Licence page for more details.

It is impossible to know what happens next in Katla volcano. But it is monitored heavily, so if anything happens. It is going to show up almost in real time on the internet.

GPS monitoring of Ice cauldron on Mýrdalsjökull glacier

In the news on Rúv yesterday (07.07.2012) they did tell about real time GPS monitoring of ice cauldron in Mýrdalsjökull glacier. But it is hoped that with this real time GPS monitoring they can give out warning sooner when a ice cauldron empties it self of the water it holds.

The news about this can be found here on Rúv News in Icelandic.

GPS-tæki komið í sigketilinn (Rúv.is, Icelandic, video)

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Earthquake swarm in SISZ continues

The earthquake swarm that I wrote about yesterday (7. July 2012) in South Icelandic Seismic Zone (SISZ) continues. The largest earthquake so far has reached magnitude 3.1. The earthquake swarm has been ongoing for almost three weeks now. But almost all of the earthquakes that have been taking place during this swarm have been small earthquakes, often with less then 2.0 in magnitude. Earthquake activity is ongoing in SISZ at the moment. It is impossible to know if there are going to be any more earthquakes with magnitude 3.0 in this area. The magnitude 3.1 earthquake was felt in Selfoss and Hveragerði towns.


The area on SISZ where this earthquake swarm is taking place. Copyright of this picture belongs to Iceland Meteorological Office.


Map that shows how the earthquake was felt in this area of Iceland. Copyright of this picture belongs to Iceland Meteorological Office.


The earthquake did appear clearly on all of my geophones. This is from Eyrarbakki, the geophone that is closest to the earthquake swarm. Copyright of this picture belongs to Iceland Meteorological Office.


This is the earthquake seen on Heklubyggð geophone station.


The earthquake seen on my Hvammstangi geophone. This is filtered at 4Hz due to local noise. This picture is released under CC Licence. Please see CC Licence for more information.


The earthquake as it was recorded on my Skeiðflöt geophone station. This picture is released under CC Licence. Please see CC Licence for more information.


The earthquake as it was recorded on Eyrarbakki geophone station. This geophone is closest to the earthquake swarm. But is noisy. This picture is released under CC Licence. Please see CC Licence for more information.


The earthquake seen on Heklubyggð geophone station. This picture is released under CC Licence. Please see CC Licence for more information.

Earthquake activity in this area of SISZ is ongoing, and shows no signs of slowing down at the moment. This earthquake swarm started about 3 weeks ago. But has mostly been making minor earthquakes. But that are earthquakes with the magnitude of 0.0 to 2.0. It is impossible to know for how long this earthquake swarm is going to continue in this area of SISZ.