Hamarinn – Page 3 – Iceland geology

September 3, 2013September 3, 2013

Interesting harmonic signals appearing around Vatnajökull glacier

In the past few hours an interesting harmonic signals have been taking place on two sil stations (so far) around Vatnajökull glacier. I do not know what is creating this harmonic tremor spikes on them, it might be water on the move or starting to move from Skaftár cauldron in Vatnajökull glacier or it might be something different that I do not know about at present time. Currently the source of this harmonic tremor is unknown and it might never been known in the worst case. I do hope to figure out in next few hours what is creating this harmonic tremor spikes on this two sil stations.

The harmonic tremor signal at Skrokkalda sil station. The harmonic tremor signal can be found at the end of the tremor plot. Copyright of this image belongs to Icelandic Meteorological Office.

The harmonic tremor signal at Jökulsel sil station. It is at the end of the tremor plot. Copyright of this image belongs to Icelandic Meteorological Office.

As I say above, the source of this tremor signal is not known. It might be bad weather in the area, traffic (unlikely due to bad weather in this part of Iceland at the moment) or something that is not known at the moment. What I can rule out at the moment is this harmonic tremor signal does not appear to come from magma movement, the frequency of the harmonic tremor is too high for that at the moment and does not show little to no energy at 0.5 to 1 Hz band. This suggest the source is something else then magma, this however does not rule out magma. Since magma is known to due many strange things under pressure and high frequency harmonic tremors are not unknown, but they are unlikely to take place rather than being a common feature in volcano activity.

For the moment the best thing that can be done is to monitor the signal and see if there are any changes and on the nearby sil stations. For the moment I do not expect any major change in this area, risk of glacier flood is still in place for this part of Vatnajökull glacier. If this harmonic tremor signal connects to that is not known at the moment.

September 2, 2013

Possible glacier flood from Skaftár cauldron

It is possible that glacier flood from Skaftákötlum cauldron has started some hours ago. According to Rúv, Icelandic Meteorological Office is now monitoring for signs that glacier flood has started. Changes in conductivity in glacier rives from Vatnajökull glacier (South-West) and the rivers that normally flood from Skaftárkötlum cauldron. It has not been confirmed that glacier flood has started yet.

At the moment it has not been confirmed that glacier flood has started, but it might start soon. I am going to post more information once I have them or when they are published.

Icelandic News about this

Fylgjast náið með Skaftárhlaupi (Rúv.is)

June 22, 2013

Update on Hamarinn volcano activity

I did check up on the activity in Hamarinn volcano today. It turns out the earthquakes in that area are mostly glacier quakes, that means they are formed by the ice and are not real earthquakes as such. It is difficult to locate glacier quakes, it is also unclear why this glacier quake activity is taking place. There is a chance of glacier flood taking place soon, but so far nothing has been detected.

I am expecting more glacier quakes to take place in the next few days to weeks in this area.

June 21, 2013June 21, 2013

Fresh dike intrusion into Bárðarbunga volcano

Interesting earthquake activity continues in Bárðarbunga volcano. There is also interesting earthquake activity taking place in Hamarinn volcano. The source of this activity is magma dike activity in Bárðarbunga volcano. It is most likely not going to result in a eruption, but might be a sign of more activity in the future.

Activity in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Meteorological Office.

There has also been activity in Hamarinn volcano, I do not know if it is connected with the activity in Bárðarbunga volcano. I find it unlikely to be the case, but I cannot rule it out at current time. It is unclear if this is new earthquake activity, it might be as simple as new SIL stations in the area, or this could be real activity increase in the area close to Hamarinn volcano. I am currently not clear on this detail as is. Last eruption in Hamarinn volcano was in July 2011, I did write about it here. It is worth keeping a eye on this activity in the Hamarinn volcano, it has proven to be a unpredictable volcano and it appears that magma is at shallow depth in it.

Blog post updated at 23:32 UTC on 20-June-2013.

April 6, 2013April 6, 2013

Magnitude 3.6 earthquake in Hamarinn volcano

Last night (05.04.2013) at 01:50 UTC a magnitude 3.6 earthquake took place in Hamarinn volcano (no GVP profile yet!). This earthquake had the depth of 2.1 km. This seems to be a dike intrusion taking place in Hamarinn volcano. No clear signs of harmonic tremor have been detected based on tremor data from Icelandic Meteorological Office.

The Hamarinn volcano is where the green star is. But that is the location of the magnitude 3.6 earthquake that took place last night. Copyright of this image belongs to Icelandic Meteorological Office.

Harmonic tremor plot do not show any harmonic tremor pulse. The signal on this harmonic tremor plot is the earthquake swarm in TFZ for most parts. Copyright of this image belongs to Icelandic Meteorological Office.

This earthquake activity is due to minor dike intrusion. Rather then something else. It is not clear if this activity is just normal activity for Hamarinn volcano or signal about something else is about take place. But as before. Hamarinn volcano remains mostly quiet for the moment.

February 28, 2013February 28, 2013

Earthquake swarm east of Grímsey (TFZ) and in Grímsfjall volcano fissure swarm

Currently there is a minor earthquake swarm east of Grímsey Island in the Tjörnes Fracture Zone. So far the largest earthquake has had the magnitude of 2.9 according to Icelandic Meteorological Office reviewed earthquake overview. Earthquake swarms are common in this area of TFZ.

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

Grímsfjall and Hamarinn volcanoes

Some internesting earthquake activity is now taking place in Grímsfjall volcano (outside the main volcano). This earthquake activity is in the fissure swarm that extents away from Grímsfjall volcano in the direction of Katla volcano fissure swarm. There has also been interesting earthquake activity taking place in Hamarinn volcano (no GVP page). But Hamarinn volcano last had a minor eruption in July of the year 2011. So far nothing suggests anything of volcanic nature is about to take place.

Earthquake activity in Grímsfjall volcano system today. Along with earthquake activity in Hamarinn volcano. Copyright of this image belongs to Icelandic Meteorological Office.

At the moment it appears that nothing besides earthquakes is going to take place in Grímsfjall volcano. But it hard to be sure given how often Grímsfjall volcano erupts. I do not yet have enough data on what is happening in Hamarinn volcano to say what is taking place there. So for now. It must just be observed.

October 16, 2012

Weak harmonic tremor pulse from Hamarinn volcano

Since around 19:00 UTC (16.10.2012) a harmonic tremor pulse has been taking place in Hamarinn volcano (Bárðarbunga volcano). There is in my view no eruption taking place at the moment. This is most likely a dike intrusion of magma somewhere in the area of Hamarinn volcano. That might however trigger an eruption. But we just need to wait and see on that for the time being. This activity is interesting, as there was a small eruption in this area in July 2011.

The harmonic tremor pulse is strongest on this SIL station. But it is weak regardless. The signal suggest this event is taking place close to this SIL station location. Copyright of this image belongs to Icelandic Meteorological Office.

The harmonic tremor pulse also appears on Skrokkalda SIL station. But is weak and can hardly be detected on it. Copyright of this image belongs to Icelandic Meteorological Office.

The harmonic tremor pulse can be seen at the end of the above SIL station traces. The harmonic tremor pulse is higher then normal background noise (wind, ocean waves, human traffic, etc) on the SIL station. I do not expect this to be noise. The signal is too strong for that. It also hard to travel in this part of Iceland in October due to bad weather and difficult conditions in the high areas of Iceland.

September 2, 2012September 2, 2012

Harmonic tremor pulse activity maybe in Hamarinn volcano

Today (02.09.2012) a harmonic tremor pulse did start in Hamarinn volcano (best guess) (Bárðarbunga volcano). This harmonic tremor pulses are intermittent and normally last for up to 20 to 30 min., at the time. What is creating them is hard to say. But this might just be hydro-thermal activity taking place in Hamarinn volcano. This might also be magma on the move inside Hamarinn volcano. But nothing is confirmed so far. I do not expect anything to be confirmed any time soon.

The harmonic tremor pluses appear on the end of the traces on this image. They are bit hard to spot for the untrained eye. But they appear as higher then background noise change in the tremor plot image.

The harmonic tremor pulse as it appears on the SIL station at Grímsfjall volcano. This is high resolution image from this IMO web page. Copyright of image belongs to Icelandic Meteorological Office.

The harmonic tremor pulse at Skrokkalda SIL station. Copyright of image belongs to Icelandic Meteorological Office.

The harmonic tremor pulse at jok SIL station. Copyright of image belongs to Icelandic Meteorological Office.

Harmonic tremor pulse at dyn SIL station. Copyright of image belongs to Icelandic Meteorological Office.

It is impossible to know what this means exactly. But so far there are no signs of eruption in the area. This activity is less then activity in July 2011 that was created by an minor eruption in Hamarinn volcano. Stronger harmonic tremor pluses appear on SIL station at longer distance. But for now (when active) most of the activity only appears on SIL stations closest to the Vatnajökull glacier. I am going to continue to monitor the current situation. I will update or make a new blog post about what is going on if anything happens.

August 30, 2012

Glacier flood confirmed from western Skaftárkatli cauldron

Today (30.08.2012) an glacier flood was confirmed from the western Skaftárkatli cauldron. This glacier flood is small as expected. But it did take several days longer to appear from Vatnajökull glacier then expected. Some hydro-thermal activity in Hamarinn volcano (Bárðarbunga volcano) seems to be currently taking place at the moment. But some harmonic tremor spikes have been taking place in the past two hours.

Harmonic tremor pulse can be seen at the end of this tremor plot from IMO. It only lasted for about 30 to 60 min. Copyright of this image belongs to Icelandic Meteorological Office.

It might be that this harmonic tremor signals are coming from other volcano system then Hamarinn volcano. This type of activity has been seen before in Hamarinn volcano and follows glacier floods from it. Given the activity last year. I cannot rule out volcano activity taking place now in Hamarinn volcano. New episode of harmonic tremor is now starting in Hamarinn volcano. Based on early observations . It seems that current activity is behaving in similar manner as did happen in July 2011 when an minor eruption took place in Hamarinn volcano. If that is the case now remains to be seen. But it should be clear in few hours what is exactly going on in Hamarinn volcano following this glacier flood.

Icelandic news about this glacier flood

Skaftárhlaup kom úr katlinum – myndband (Rúv.is, video)
Hlaupið kom úr vestari katlinum (mbl.is)

August 27, 2012

Still no glacier flood in Skaftá glacier river

For reasons that are unknown. No glacier flood has yet taken place in Skaftá glacier river. Even if the western Skaftárketill cauldron in Vatnajökull glacier has emptied. It is now expected that Hamarinn eastern cauldron is going to empty it self soon. But when that might happen is impossible to know for sure.

Ice-quake activity continues in Vatnajökull glacier. But that suggests the water is on the move under the glacier. Copyright of this image belongs to Iceland Meteorological Office.

The glacier flood is expected to be small. But it won’t go unnoticed once started. As the glacier river get’s darker and conductivity in the water increases greatly during the flood. I am going to try and keep an eye out for more information on this glacier flood.

Icelandic News about this

Ekkert hlaup hafið (Rúv.is)

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