Overview of Hamarinn volcano current activity

Here is a short overview of the Hamarinn volcano activity this summer. From what I can gather in the current data this is most likely not over. During the past few days there have been at least suspected two minor eruption in Hamarinn volcano. But it hard to confirm it due to glacier that is covering this area.

This all starts on 12. July 2011 at 07:30 UTC with this event here.


The tremor spike on 12. July 2011 at 07:49 UTC. Copyright of this picture belongs to Icelandic Met Office.

When the clock is around 19:10 UTC the same day the tremor chart looks like this.


The tremor spikes are now three on 12. July 2011 at 19:09 UTC. Copyright of this picture belongs to Icelandic Met Office.

On the 13. July 2011 the tremor plot looks like this. But at that time the glacier flood had started and broken from the Vatnajökull glacier.


The tremor chart at 13. July 2011 at 01:10 UTC. Copyright of this picture belongs to Icelandic Met Office.


The tremor chart at 13. July 2011 at 12:59 UTC. Copyright of this picture belongs to Icelandic Met Office.

Then there was a short period of break when nothing interesting happened in Hamarinn volcano. That break did last until 16. July 2011 when a new, but smaller spike did appear on Skrokkalda SIL station.


The tremor at 16. July 2011 at 15:22 UTC. It is not fully clear what did happen at this time. But this was most likely a earthquake in Hamarinn volcano. But that is yet unconfirmed at this time. Copyright of this picture belongs to Icelandic Met Office.

Then there is a new break that lasts until 1. August when a earthquakes happens deep under Bárðarbunga volcano. But the deepest earthquake had the depth of 25.2 km. But it is also important to notice this earthquake that took place on 13. July 2011 and it is from Hamarinn volcano.


The earthquake from Hamarinn volcano. This picture is released under Creative Commons licence. Please see licence web page for more details.

On the 3. August 2011 around 02:00 UTC a new harmonic tremor spike starts to be visible on Skrokkalda SIL station.


The tremor plot at 01:55 UTC on 3. August 2011. Copyright of this picture belongs to Icelandic Met Office.

This day two minor harmonic tremor happens. A change in Skaftá glacier river is noticed. That is higher conductivity and slightly more water. It was announced in the news that a Skaftá glacier river flood was about to start from the eastern glacier cauldron that is formed above the Hamarinn volcano. Today however that does not seem to be the case. As no glacier flood has taken place so far.

Today (5. August 2011) there was a new harmonic tremor spike on Skrokkalda SIL station. It did follow the same pattern as before. It started and lasted for about 20 to 60 minutes or about that long.


The tremor chart 5. August 2011 at 17:38 UTC. Copyright of this image belongs to Icelandic Met Office.

So far today only one harmonic tremor has been detected. But given the past experience that is unlikely to hold for a long time now. But it is impossible to know when a new event starts or how big it is going to be.

The original event on 12. July 2011 did create new cauldron in the glacier. This map from Icelandic Met Office shows the location of those new cauldrons. But it has been marked with a star on the map. The coloured dots are earthquakes in this area over the past few years.


Map of the area that is currently active in Hamarinn volcano. Copyright of this image belongs to Icelandic Met Office.

Given the current data I am expect a full scale eruption in this area soon. When is hard to know for sure. But until that happens there are going to be more smaller eruptions in this area. I do not know why there is a lack of earthquakes following this events. I cannot explain it. But because of that this can only be seen after it has started on the tremor charts.

Hekla volcano earthquake from early this morning

Here is the earthquake that took place in Hekla volcano this morning. This earthquake was small, just ML2.02 with the depth of 4.8 km. Because of how close this earthquake was to my geophone at Heklubyggð it did appear clearly on it.


The earthquake at Hekla volcano this morning. This picture is released under Creative Commons License, see License web page for more details.

No aftershocks where recorded after this earthquake and nothing suggests that a Hekla volcano is about to erupt at present time. But that can change without warning at any time.

Sharp rise in harmonic tremor on Skrokkalda and Grímsfjall SIL station (among others)

There is a sharp rise in harmonic tremor on the Skrokkalda and Grímsfjall SIL station. I do not know yet what volcano is responsible for it. But the Hamarinn volcano is a suspect at the moment.

Current tremor plot.


The tremor spike is at the end of this tremor plot. Copyright of this picture belongs to Icelandic Met Office.


The tremor spike is at the end of this tremor plot. Copyright of this picture belongs to Icelandic Met Office.

I am going to post more information about what is going on when I know more. This blog post might get updated soon if needed.

Interesting earthquakes in Bárðarbunga volcano system (Hamarinn volcano)

At 02:06 and 02:07 UTC there where interesting earthquakes in Bárðarbunga volcano system. What makes them interesting is that fact they did happen at 0.6 km depth one of them. But this area did see some volcano related activity (speculated) earlier this summer, that did result in large glacier flood. But it has been suggested that a minor eruption took place there around 10. July 2011.


The two earthquakes can be seen as spikes at the end of this tremor plot from Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.

What makes this earthquakes so interesting is that they seem to have a low period component in them. But it was seen on the Kálfafell SIL station, and other SIL station that was decent distance from the source of the earthquake.


The two earthquakes can be seen as spikes at the end of this tremor plot from Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.

Currently there is nothing that suggests that a eruption is about to start in this area. But that can change without warning given the current status of Hamarinn volcano system.

Glacier flood has started in Skaftá river

The latests news is that a glacier flood has started in Skaftá river. At the moment this glacier flood does not appear to be big, as there was also a glacier flood in this river last year. Because of this short time, there has not been a lot of water collected in the western cauldron that is emptying now. It was clear today that it was the western cauldron that had emptied when scientists did fly over the area earlier today.

This glacier flood is often early event and has been since the year 1955. Following this glacier flood there is often spike in harmonic tremor because magma goes on the move due to sudden pressure release in this area. So far it has not been able to trigger a eruption in Hamarinn volcano. It remains to be seen if that has changed or not.

Icelandic News about this

Hlaup hafið í Skaftá (Rúv.is, Pictures, Icelandic)
Rennsli eykst í Skaftá (Vísir.is)
Hlaupið komið í Skaftá (mbl.is)

No glacier flood yet from Hamarinn volcano, but it is on it’s way

At current time (around 20:30 UTC) it has been observed that no glacier flood has started in Skaftá river. But the glacier flood is expected to start in the river around midnight, but the river might start to grow around 19:00 to 21:00 UTC. According to latest news the river has however started to get darker and conductivity in the water has started rise since this morning, but that was the signal that a glacier flood was about to start. Glacier flood tremor have also been dropping in the last few hours according to the latests news that I have seen (but I am hoping for a update on that detail).

The source of this glacier flood is a hydrothermal area in Hamarinn volcano (part of Bárðarbunga volcano). This area also did have a glacier flood last year. But last year there where two glacier floods in Skaftá river in June 2010, see reports here in Iceland at Icelandic Met Office web page.

This hydrothermal area in Hamarinn volcano is in two cauldrons in the Vatnajökull glacier. With time they fill with water that then breaks ice when the pressure is enough in the cauldrons due to water levels. It remains a question if the surprise glacier flood earlier this month from Hamarinn volcano has something to do with this. But at current time that is only speculation. But if the hydrothermal area is unusually highly active, or there has been some change it is hard to know for sure the size of this glacier flood.

Currently however the experts are expecting a small glacier flood due the fact there where two glacier floods from this area last year. But we however have to wait until midnight until we know what is the actual size of this glacier flood.

Icelandic News about this

Skaftárhlaup ekki enn hafið (Rúv.is)
Skaftárhlaupið komið í byggð eftir sólarhring (Vísir.is)
Engin merki um hlaup ennþá (mbl.is)

Grímsfjall volcano inflates after the large May 2011 eruption

It can be sad that Grímsfjall volcano did not waste any time starting to prepare for next eruption after the large May 2011 eruption. But that eruption was the largest one in at least 140 years or so. This large eruption did mean that there was a large deflation that took place during the eruption. Where the most deflation was around 250mm down, and around 300mm north, and around 350mm east.

Since then Grímsfjall volcano has however been inflating at interestingly high speed. Currently the GPS data shows that it has reached around 250mm east, north and 200mm up since the eruption. But the magma chamber is going to expand horizontal before it expands upwards (think of this in 3D). So it is going to be a while until a inflation upwards is going to be seen.

The GPS data is clear on this as can bee seen here.


Current inflation at 27. July 2011. Copyright of this picture belongs to Icelandic Met Office.

It is hard to know when Grímsfjall volcano is going to erupt next after this big eruption. But it might take few years until we see a new eruption in Grímsfjall volcano.

Earthquake swarm and minor harmonic tremor in Katla volcano

There has been a minor earthquake swarm in Katla volcano today. This earthquake swarm started around 09:00 UTC and lasted with breaks until 14:39 UTC. The largest earthquake in this swarm was ML1.7 with the depth of 3.5 km. Following this earthquake swarm there was a small harmonic tremor spike seen on few SIL stations around Katla volcano. It is unknown at this time if there has been a small glacier flood taking place. But if that is the case, it should be known in the next few hours if that is the case or not.


The earthquake swarm in Katla volcano caldera. Copyright of this picture belongs to Icelandic Met Office.


The harmonic tremor spike can be seen on this SIL station. It is located close to the end of tremor plot. Copyright of this picture belongs to Icelandic Met Office.


The harmonic tremor spike can be seen on this SIL station. It is located close to the end of tremor plot. Copyright of this picture belongs to Icelandic Met Office.

This harmonic tremor is small, but larger then last harmonic tremor that took place in this are about one week ago (far as I can remember). Currently there is nothing that suggests that eruption is imminent. This is just earthquake activity in the same place as it has been for the past five or so weeks.

Sorry for the short blog post. I have gone sick with some cold. No advice needed on how to get rid of it. That is going to take few days on it’s own.

Currently all is quiet in Iceland

At the moment it is rather quiet in Iceland in earthquakes and volcanoes. When that might change is impossible to say. But in the last few days there have been minor earthquake swarms on the Reykjanes Ridge. It is not related to volcanism, but rather tectonic movement along the rift zone.

There is continued minor earthquake swarm activity in Katla volcano. But it has quieted down from about two weeks ago. For the moment, the glacier floods seems to have stopped.

Other then this minor earthquake activity, everything is quiet in Iceland.

Small glacier flood from Mýrdalsjökull glacier (Katla volcano)

During the night (and when I had unstable power) there was a small glacier flood from Mýrdalsjökull volcano. Some minor harmonic tremor change was detected following this glacier flood. This even was small one, many times smaller then what did happen on the 8 to 9 July 2011. Due to security concerns the Civil Emergency Authority did close the main road in Iceland for this area. Since they never know how big the flood can actually be. The main road was closed for about one hour. This glacier flood was detected around midnight 20 to 21 July 2011.

This flood is actually so small it is hard to see it on the harmonic tremor plot from the SIL stations around Katla volcano.


Tremor plot from 07:50 UTC this morning. It is hard to see the harmonic tremor from this minor glacier flood. Copyright of this image belongs to Icelandic Met Office.


Tremor plot from 07:50 UTC this morning. It is hard to see the harmonic tremor from this minor glacier flood. Copyright of this image belongs to Icelandic Met Office.


Tremor plot from 07:50 UTC this morning. It is hard to see the harmonic tremor from this minor glacier flood. Copyright of this image belongs to Icelandic Met Office.

What happens next is impossible to know for now. But it seems that activity continues to be high in Katla volcano. All that can be done is to wait and see what happens. But I am going to continue to monitor the changes in Katla volcano as best that I can do until I finish my summer job (29. July).

Icelandic News about this.

Aukin leiðni í Múlakvísl og órói í Mýrdalsjökli (Vísir.is, Icelandic)
Náið fylgst með Mýrdalsjökli (mbl.is, Icelandic)
Hringvegurinn opinn á ný (Rúv.is, Icelandic)
Breytingar í Múlakvísl (Rúv.is, Icelandic)