Category: Earthquakes

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Still quiet in Iceland

It is continues to be quiet in Iceland in regards to earthquakes. Just small earthquakes swarms have been taking place in Krýsuvík volcano and in Hengill volcano.

Sadly I currently don’t have a time to write an decent blog post about other interesting things in Icelandic geology or historic eruptions in Iceland (translated to english). But if nothing interesting happens, I plan to do so next weekend.

Other: My plans are not going as I planned. I am only going to be in school until the end of this year (starting from August) since I cannot afford it (yea, I am that broke). But school is going to give me more time to write on this blog rather then I am not working. In the new year of 2012 I am just going to do what I do so well now. Write, and write some more on this blog and a book or two. But I don’t think that I can manage to write more then that in one year.

I also want to thank my readers for this patents for the lack of updates and blog post this summer. As I am working all days now, except weekends from 08:15 to 16:15 UTC. It is an hard work that makes me tired, so I don’t have an lot of energy to write after the day.

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Quiet in Iceland. Picture of Grímsfjall volcano new crater lake

It has been quiet in Iceland. Some minor earthquake swarms have taken place. But they where all less then 50 earthquakes with sizes for most part less then ML3.0. So this is going to be an short blog post.

At Eruptions at BigThink Erik did link to an interesting picture of the aftermath of last eruption in Grímsfjall volcano.

Due to how quiet it is in Iceland. I am not going to have this blog post longer. But on other note, I am going to make fewer blog post this summer since I am working during the day and I am really tiered after I finish working. But I am going to due my best in keeping new blog post coming.

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Earthquake swarm in Presthnjúkar volcano. Update on Katla volcano

Presthnjúkar volcano: Few days ago an earthquake swarm did start in Presthnjúkar volcano. This earthquake swarm is entirely tectonic in nature. There is nothing that suggests that this earthquake swarm is connected to magma movements inside Presthnjúkar volcano system. So far this earthquake swarm has been slow and small. But the largest earthquakes have gone up to ML3.3 in size according to Icelandic Met Office.


The location of current earthquake swarm in Presthnjúkar volcano. Copyright of this picture belongs to Icelandic Met Office.

Katla volcano: Over the last 18 hours it has been quiet in Katla volcano. As no more earthquakes have been detected from it. I would not be surprised if there are more earthquakes swarms in Katla volcano in the next few weeks and months. It is an well known fact that Katla volcano is heading to an eruption. But nobody knows when that is going to happen.


Location of the earthquakes in Katla volcano yesterday. Copyright of this picture belongs to Icelandic Met Office.

Besides this two highlights of earthquake activity in Iceland. It has been rather quiet in the past few weeks. With just from ~100 to ~300 earthquakes during the week.

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Earthquake swarm in Katla volcano

Around 17:10 UTC an earthquake swarm did start in Katla volcano. This earthquake swarm is focused inside the Katla caldera at small point. The one earthquake that I have so far been able to record was an long period earthquake, but that suggests that this earthquake was created by magma movement. At current time I am not sure from where this earthquake did originate from. But from Goðabunga area in Katla volcano this types of earthquakes are common and no surprise at all.

At current time I do not know what this means for Katla volcano. But so far no increase in harmonic tremor has been detected on the seismometers around Katla volcano. But that might not start at current time, as harmonic tremor is only going to increase when magma starts to move inside the Katla volcano, like did happen in Grímsfjall volcano few weeks ago.

The location of this earthquake swarm strongly suggests that what is going on in Katla volcano is an dike intrusion in the Katla caldera. If that is powerful enough to start an eruption is an question remained unanswered at current time.


Area of activity is marked by the earthquakes. Looks like an dike intrusion into Katla caldera. Copyright of this picture belongs to Icelandic Met Office.

I am going to update or post new blog posts as this continues to develop. I do not think that this events are over. But it is hard to know for sure, since volcanoes are impossible to predict.

Post post updated at 18:39 UTC.

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General update of earthquake activity in Iceland and other things

Here is finally an new blog post from me. This week has been busy. As I did move to Hvammstangi again for this summer. But I did move to Iceland on the 5. June 2011. But just for the next 1 to 3 years, depending on how things goes for me. My work is hard, so I might not often have energy to write new blog post during the week. But I am going to do my best.

Now, the earthquake information on what has been going on in Iceland for the past two weeks or so.

Katla volcano: Even after the harmonic tremor pulse last week. Nothing special has been going on in Katla volcano. But it did come to my attentions that Icelandic Met Office did notice that in Week 23 there have been explosions (mine for road work in the area). So when an “earthquake” appears in that area. It means that an mine explosion have taken place in that area. I do not know when they are going to stop mining operations in this area.

Presthnjúkar: There continues some earthquake activity in the Presthnjúkar area. This earthquake activity appears to be tectonic and nothing else. The latest earthquake swarm taking place there appear to be starting tonight. It is hard to be sure how it is going to develop over the past few hours.

Other: There is currently not a lot other thing going on in Iceland.

I hope to make an better post tomorrow. When I am well rested and focused.

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Earthquake swarm in South Langjökull volcano and Krýsuvík volcano

Today has been spotted with earthquake swarms in Iceland. This earthquake swarms have not been big so far in both terms of earthquakes and size of the earthquakes. With the biggest earthquakes in South Langjökull volcano (Presthnjúkar). The biggest earthquakes in South Langjökull volcano have been around ML2.5 in size. With the average depth of 10 to 5 km. Total number of earthquakes is something around 39 and that is an small earthquake swarm.

The area in question is known for earthquake activity. Few years ago there was an earthquake swarm in this area with several ML4.0+ earthquakes. This area did also see earthquake swarm earlier this year. So far nothing suggests that an eruption is close in this area.


Map from Icelandic Met Office showing the area with the earthquake swarm. Click on the picture to get full size. Copyright of this picture belongs to Icelandic Met Office.

Krýsuvík volcano did also have an minor earthquake swarm today. The largest earthquake in Krýsuvík volcano was ML2.1 with the depth of 3.9 km. So far this earthquake swarm has been an minor one. With just over 32 earthquakes happening today.

Other earthquake activity in Iceland is currently not an lot. A ML3.1 earthquake took place few days ago in TFZ in an area that commonly has earthquake swarms. That area does not have any volcanoes, so earthquakes there are only connected to faults in the fault lines in that area.

Blog post updated at 23:29 UTC on 7. June 2011.
Blog post updated at 23:35 UTC on 7. June 2011.

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Everything has gone quiet again in Iceland

After the eruption in Grímsfjall volcano last week everything has gone quiet again in Iceland. Earthquake activity is currently low and all earthquake activity in volcanoes remains low at current time.

Because of that I am going to take me an little break until I move to Iceland. Unless something of interest happens in Iceland. Part of this time I am going to in the sun here in Denmark and check out the beautiful ladies that populate Denmark (if you are offended by this, then I am sorry for you). 🙂

For those how want to know about my money status. June is going to be rather broke-ish. So all supported is welcomed. But I am not going to request it specially as I have done before. Thanks for the support all. 🙂

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Eruption in Grímsvötn appears to be over (hopefully correct this time around)

It appears that the eruption in Grímsvötn / Grímsfjall volcano is over or is about to end, but authorities in Iceland might not declare the eruption over until after next weekend. No ash plume has been observed for over 24 hours now from Grímsfjall volcano. Harmonic tremor pulses are still taking place in Grímsfjall volcano and it is still dangerous to get close to the eruption site. As explosion still take place in the eruption area and that makes going there dangerous. It is not only the area where the water is that is having explosions. There are also gas and explosions taking place in the crater rims and nearby area. According to news today Icelandic Met Office did stop recoding the eruption in Grímsfjall volcano around 07:00 UTC this morning (28. May 2011). But harmonic tremor pluses might still be taking place in Grímsfjall volcano. But the SIL stations around Grímsfjall volcano have now started to record background noise again, including the SIL station at Grímsfjall volcano.

Earthquake activity has continued at similar levels as before the eruption took place. I am not sure why that is. But this might indicate that Grímsfjall volcano has already started to prepare it’s next eruption. But when that might happen is a question that only time is going to answer. The main earthquake activity is currently taking place NW of Grímsfjall volcano, and SW of Grímsfjall volcano.

According to automatic GPS data it appears that Grímsfjall volcano has started to inflate again. This inflation appears to be rather rapid at current moment. But it appears to be close to 1mm/day inflation to the south and east. This means that new magma has already started to flow into Grímsfjall volcano magma chamber and magma system from greater depth. So far Grímsfjall volcano has not started to inflate upwards and it might be an while until that happens, as there might be enough space for the magma to move into inside Grímsfjall volcano.

Measurements of the volcano tephra that did fall, along with measurement of the volcano ash that did fall have recorded the depth up to 170 cm in some areas of Vatnajökull glacier even at distance of 8 km from the eruption site. This is going to create problem in the summer when it is dry and the wind blows this volcano ash around Iceland. But mostly in the areas that where closest to the main ash fall areas.

Update 1: According to news on Vísir.is the Icelandic Coast Guard did see an plume with the hight of 1,5 km yesterday. This plume was however mostly made out of steam rather then volcano ash. The news about this can be found here, along with an picture of the plume. Here is an second news of this steam plume that was seen yesterday.

Update 2: According to news on Rúv there is small harmonic tremor being recorded. But most of the time, no harmonic tremors are being detected from Grímsfjall volcano. The Rúv news can be found here (Icelandic, Picture). It also has an new picture of the eruption crater. But this picture was taken around 10:00 UTC today (28. May 2011).

Icelandic News about this. Use Google translate on this for an risky translation.

Eldgosið mælist ekki lengur á jarðskjálftamælum (Vísir.is, Icelandic)
Enginn gosmökkur í dag (From 27. May 2011, Rúv.is, Icelandic)

Blog post updated at 19:11 UTC.
Blog post updated at 20:15 UTC.

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Explosions are still taking place in Grímsvötn crater

While the activity has almost stopped in Grímsfjall volcano, but there are still explosions taking place in Grímsvötn lake where the eruption took place due to magma going up, explosions take place all over the fissure at random times. That makes travelling to this area really dangerous thing to do. Ash fall is still taking place in Grímsfjall volcano when explosions take place. But the ash fall is limited to the local area in Grímsfjall volcano. Because of this, the official word is that the eruption is not yet over. Even if it just an small eruption at the moment. So far there is no data that suggests that new magma is currently flowing into Grímsfjall volcano. This is according to news in Icelandic media.

An new caldera (correct word?) has formed in the glacier close to the eruption site. But that suggests that a lot of heat is below in the glacier and is creating strong melt where this taking place. This is according to news on Rúv. But they don’t say where this glacier melt is taking place. But it can be assumed that this formation is somewhere close to the current eruption site. But when I know more about this location. I am going to update this post when I can.

Harmonic tremors pulses are still being detected from Grímsfjall volcano up to 200 km away from the volcano. Why they are still taking place while there is no eruption taking place is unknown to me. It is important to notice that currently the harmonic tremor is slowly dropping for now. But it might increase again without any warning. For now there is no way to know what this tremor means for Grímsfjall volcano.

Automatic GPS data from Icelandic Met Office tells an interesting story. According to this data (it might not be 100% accurate due to nature of GPS) Grímsfjall volcano has moved close to 320mm to the west, close to 350mm to the north, it has also lowered down about 250mm. This is major movement in Grímfjall volcano. To compare it with something, Eyjafjallajökull volcano only inflated about 60mm before it did erupt. This is many times more deflation that took place in Grímsfjall volcano then in Eyjafjallajökull volcano for example.

Earthquakes are still taking place SE and SSE of Grímsfjall volcano. There is no volcano at this location. So I am assuming that this are tectonic earthquakes taking place due to stress changes in the crust around Grímsfjall volcano. All earthquakes so far have been small but with the depth from 15 and up to 5 km.

Extra: According to new news (while I was writing this blog post). The Civil Emergency Authority in Iceland has lowered the alert level from danger level to alert level. News about that can be read here (Icelandic, mbl.is)

Icelandic News about this. Google Translate in an maze. It might work or maybe not.

Enn sprengivirkni í Grímsvötnum (Rúv.is, Icelandic)
Jarðeðlisfræðingur: Orðum ofaukið að gosinu sé lokið (Vísir.is, Icelandic)

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The eruption in Grímsvötn / Grímsfjall volcano most likely not over

Here is a interesting paradox. While the eruption it self has currently stopped in Grímsfjall volcano. The tremor chart around Grímsfjall volcano is still acting like there is a eruption ongoing. I do not know why this is like this. But because of that I don’t think that geologist that monitor Grímsvötn eruption in Iceland are not ready to call off this eruption at current time. At least that is what the news did say at 12:20 UTC on Rúv.

They are also issuing warning to people not going to close to the volcano. As explosions due happen and they can throw up rocks that weight up to 1 ton. If anyone gets hit by that rock, that person does not have to worry about what happens next. The save distance for viewing the crater is estimated to be 2 km or more.

I have no idea what happens next. But I am guessing that this eruption might resume soon and without an any warning at all.

The tremor plot at 15:00 UTC. Pictures are from Icelandic Met Office.

This pattern of tremor is interesting. I am yet unsure what it means. But my guess is that this eruption is not over. Even if it has just stopped for now. I normally consider eruption over when the tremor has gone back into background noise (wind, ice, ocean etc..). That has not yet happened with Grímsfjall volcano eruption at this moment.

Update 1: Here is an tremor plot that Icelandic Met Office has released. The article where this picture is from Icelandic Met Office can be read here, it is in english.


Click on the picture for full size. I must point out that this picture is big. Copyright of this picture belongs to Icelandic Met Office.

Blog post updated at 20:46 UTC.