Earthquake swarm in Askja volcano and Katla volcano

During the night there was a earthquake swarm in Askja volcano and in Katla volcano. The earthquake swarm in Katla volcano might be ongoing, but it is hard to know that for sure at the moment.

The earthquake swarm in Askja volcano are signs that volcano is preparing for a eruption period. But it seems like that magma has been starting to collecting in Askja volcano last year (in March of 2010). This progress also seems to be moving along faster then I did expect last year. But the earthquake swarm that took place during night was because if a possible dike intrusion from Askja volcano that got into the crust inside Askja volcano fissure swarm. So far the pressure of the magma is not high enough to start a eruption and I am unsure how long this progress needs to continue before Askja volcano is ready for a eruption. The largest earthquake that happened during the night was ML3.4 and on around 1 km depth according to the news on Rúv.


The earthquake area in Askja volcano. It is outside the main Askja volcano, but inside Askja volcano fissure swarm, the star marks the location of the ML3.2 earthquake (automatic size). Copyright of this picture belongs to Iceland Met Office.

Earthquake activity continues in Katla volcano as before. Most of the earthquakes are as before just small ones. Currently the earthquakes do not appear to be from dike intrusion as happened last week (5 October, 2011) with the earthquakes that where up to ML3.9 in size (checked data). After this large earthquake swarm activity dropped considerably. But it has been picking up again slowly during the week. But earthquake observation has been difficult due to frequent storms during the past two weeks that have been passing over Iceland. This storms have had wind up to 30m/s and wind gusts up to 56m/s (recorded).


The earthquake swarm in Katla volcano caldera. This area was active this summer when there was a minor eruption in Katla volcano. Copyright of this picture belongs to Iceland Met Office.

For the moment it is hard to know what happens next in Katla volcano or in Askja volcano. But it is clear that Askja volcano is preparing for a eruption (along with Kverkfjöll volcano). It is clear that Katla volcano is continuing to prepare for a eruption. But it is impossible to know when and how big that eruption might be. Until a eruption takes place, more dike intrusions with following earthquake swarms should be expected in Katla volcano.

Note: I am going to write more on El Hierro volcano (Canary Islands, Spain) later today. When I know more on what is going on in that volcano. But information gathering takes a little time when it is in a language that I do not properly understand yet.

News on this from Rúv.is.

Jarðskjálfti við Lokatind (Rúv.is, Icelandic)

Blog post updated at 14:23 UTC on 11 October, 2011

Deep earthquake in Herðurbreiðarfjöll volcano (Askja volcano fissure swarm)

Today at 06:57 UTC in Iceland there was a ML0.2 earthquake east of Herðurbreiðarfjöll volcano. While the size of this earthquake is really small. It is the depth that is interesting in this case. The depth of this earthquake was at 25,7 km depth. This is a interesting depth given the increase in earthquake activity in Askja volcano.

According to my geological map (a rather new one) the mountain named Herðubreiðarfjöll is a volcano that is inside Askja volcano fissure swarm. A common thing that happens in Iceland. This area has many active fault lines and has erupted in modern time. But I do not know when this volcano last erupted, as there are no information on Herðurbreiðarfjöll volcano activity in the GVP database and I have not found anything useful on the internet about this volcano.

Earthquake activity continues in Askja volcano. But at slower rate then before. Other then this, it is quiet in Iceland as it has been for the past few weeks.

The magma below Upptyppingar tuff mountains

Upptyppingar are a tuff mountains in the east highlands in Iceland. There formation is contributed to a sub-glacier eruption in this area around 12.000 years ago. A second older sub-glacier eruption feature is also present in this area, it is called Álftadalsdyngja. It is believed that it did form around 700.000 years ago in a basalt eruption in this area. Upptyppingar and Álftadalsdyngja are both inside Kverkfjöll volcano fissure swarm.


Map of the area. Copyright of this picture belongs to how created it. Author unknown. Picture is from here.

In the year 2007 (Week 50) a earthquake swarms started to appear in Upptyppingar area. Earthquake activity in Upptyppingar area have continued since then. With total number of earthquakes in this area since the year 2007 is something over 6000 total. The reason why earthquakes are happening in this location is because magma is pushing up trough the crust in this area. This has been confirmed by GPS measurements since the year 2007.

It is my opinion that increased activity in Askja volcano might trigger a eruption in Upptyppingar area or in nearby area. As the risk of dike intrusion from Askja volcano into the Upptyppingar magma sill might trigger a large fissure type of event in this area. This is just speculation based on observed data. So please take note of that fact. The reason why I fear dike intrusion from Askja volcano is due to the changes that Upptyppingar magma has created in the nearby crust. But if this happens depends on how Askja volcano eruptions are going to behave in the future.

Here are some scientific data on Upptyppingar and the magma that has been collecting at 15 km depth below Upptyppingar mountains since the year 2007.

EARTHQUAKE SWARMS AT UPPTYPPINGAR, NORTH-EAST ICELAND: A SIGN OF MAGMA INTRUSION? (pdf, study)


Location of the earthquakes since the year 2007. Copyright of this picture belongs to Icelandic Met Office. Picture is from here.


Depth of the earthquakes in the year 2007. As can be seen, the magma moved upwards with time. Copyright of this picture belongs to how created it. Author unknown. Picture is from here.


Estimated location of the magma below Upptyppingar mountain. This location is based on earthquakes and other measurements. Copyright of this picture belongs to how created it. Author unknown. Picture is from here.

What happens with Upptyppingar is now just a question of waiting and seeing. But there is also a good chance that this magma is never going to reach the surface in a eruption and is just going to cool down there and form a basalt dike that is going to be exposed in few million years when the weather and ice remove the rocks on top of it.

Earthquake in Askja volcano last night

Here is a picture of a earthquake that took place in Askja volcano last night. This earthquake was bearly visable on my geophone close to Hekla volcano. From this data it is clear that the earthquakes are created by magma movements inside Askja volcano. But the earthquake swarm is taking place on the edge of Askja volcano main system. It is not happening outside as it might appear.

It is also worth pointing out that not all of Askja volcano earthquakes might appear on the automatic SIL system. But most of them should do so. As Askja volcano is remote and in a unpopulated area there should not be any damage from a eruption. The only damage might happen if there is a eruption in Askja caldera lake due to ash cloud that might form.


Askja volcano earthquake. This is low pass filtered at 1Hz. This image is released under Creative Commons License, see top link for more information. Click on this picture for full resolution.

This earthquake has magma signature from the looks of the earthquake signal. But due to distance it is hard to be sure on that.

When this is written a tremor pulse appears to be starting in Askja volcano. But this might also be a swarm of micro earthquakes taking place in Askja volcano without the earthquakes appearing on the automatic SIL system. At this point it is hard to know for sure, as this activity is new.


Locations of the earthquakes in relations to the Askja volcano system. As can be seen on this map from Icelandic Met Office, the earthquakes are clearly inside Askja volcano. Even if they are not at the main caldera. Picture is from Icelandic Met Office web site. Copyright of this picture belongs to Icelandic Met Office.

Blog post updated at 16:37 UTC on 5 May 2011. Picture is added.

More information on the Askja volcano earthquakes

The earthquake activity in Askja volcano continues to evolve at rather fast phase. A lot faster phase then I did originally expect. Far as I can tell from the Icelandic Met Office SIL data (tremor plots). The earthquakes that are now taking place in north Askja volcano appear to be mostly magma related earthquakes. The strongest earthquake so far did happen today and had the size ML2.5 with the depth of 0.1 km. The deepest earthquake so far took also place today and had the depth of 19,6 km. It had the size ML1.4.

However earthquakes with the depth of 22 km has been recorded close to Herðubreiðartögl. Few days ago a tornillo earthquakes (most likely the case now. But yet unconfirmed from my point of view) started too appear in Askja volcano. But that means that magma is on the move in Askja volcano. Currently this might also be the case with the earthquake activity east of Askja volcano. But at this moment it is a bit more unclear what the activity east of Askja volcano means. But it is also possible that magma is also pushing east from Askja volcano. But so far earthquake activity east of Askja volcano has been different then from the earthquake activity north of Askja volcano. But it has not been focuesed on a single spot like the earthquake activity in north part of Askja volcano system.

It is unclear at this moment how this is going to evolve in the long term. But no reports of increased hydrothermal activity have so far appeared in the news. Currently the activity is rather low, so a eruption is not yet imminent in Askja volcano. But that might change without any warning at all at any time.


Current Askja volcano earthquake activity. Click on this picture for full resolution. Picture is from Icelandic Met Office web site. Copyright of this picture belongs too them.

Due to distance. I do not record any small earthquakes from Askja volcano. But they need to be larger then ML3.0 to appear on my geophone network.

Overview of the Askja volcano earthquakes

This is just a short overview of the Askja volcano earthquakes that have been taking place over the past few weeks. I do not at this have a good picture of what is happening in Askja volcano.

In Week 15 earthquake activity started north of Askja volcano. This activity have been growing since then, with considerable difference between Week 16 and Week 17. Currently the earthquake activity is ongoing. It is not clear if this earthquake activity has slowed down or not. Many of the earthquakes that are taking place north of Askja volcano are shallow. But most of the earthquakes are happening on a depth from 1 km and up to 0.0 km. I am currently unclear on why the activity is so shallows as seems to be the case.

A second set of earthquakes have also been taking place in Askja volcano system. But this earthquakes are taking place east of main Askja volcano. But Askja volcano fissure system goes east and then north from the main volcano. It also goes several km south of main Askja volcano. But that area has not seen any activity so far. While the activity east of Askja volcano is not clustered as it is north of it. It is showing many of the same signs as the earthquakes north of Askja volcano. They are shallows with most of the earthquakes taking place in less then 1 km depth. As before I am not sure why the earthquakes are taking place on less then 1 km depth. But one idea for both the earthquakes north and east of Askja volcano is that there is magma pushing up the bedrock north and east of Askja volcano. But does not at this time have the power to break up trough the crust and start a eruption. Only one deep earthquake has so far been recored, it was on a 22,8 km depth. The location of this earthquake was not far from Herðubreiðartöglum mountains.

Due to lack of GPS data it is hard to see any deflation or deformation in Askja volcano. But it has been known since last year (2010) that Askja volcano has started to prepare for a eruption. But it remains unclear how long it is until Askja volcano is fully ready for a eruption. Last eruptions that took place in Askja volcano where in the years 1961, 1938, 1926, 1924, 1923. More on Askja volcano eruption history here (GVP web page).

About the earthquakes north of Askja volcano

The earthquakes that are now taking place north of Askja volcano are interesting for many reasons. One of the biggest reason why this earthquakes are interesting is the fact how shallow they are. But it is also interesting on how small the area the earthquakes are taking place on.

This earthquake activity did start in Week 15 with one earthquake. In Week 16 the activity had grown up to few earthquakes. In Week 17 (current) the activity has continued to grow in this area. This activity currently stands out in the earthquake activity around Askja volcano.

While it is common for Icelandic volcanoes to erupt from a central vent. It is also common for Icelandic volcanoes too erupt from fissures (like Fimmvörðuháls Eruption 2010). One of the clues to this type of eruption close to a central volcano is a earthquake activity. It is my opinion that this earthquake activity qualifies as pre-activity for a fissure eruption in the area of Askja volcano. But if anything happens soon is a different question and it is impossible to predict for now. It is however sure that before such eruption the earthquake activity in this area needs to increase a lot more from the current levels of earthquake activity that are being seen today.

Currently no eruption is immanent in Askja volcano.

Interesting earthquakes north of Askja volcano

There is a interesting cluster of earthquakes north of Askja volcano. What is most interesting is the fact that this earthquakes are shallow This cluster of earthquakes is most interesting for the fact that it is shallow. The depth of the earthquakes is from 8.4 km and up to 0.1 km (~100 meters). This suggests that this is a dike intrusion is making. But appears to be growing slowly (a bit unclear at the moment however). But at this time it is impossible to know if this possible dike intrusion makes it too the surface or not.

History tells that it is not unclear for Askja volcano to erupt in small fissures. But that last happened in the Askja eruption in the year 1961.

Currently it is unclear what is going on north of Askja volcano. But this is for sure evolving into something in my opinion. But the question remains how long this is going to take. But this process has already been ongoing now for about 14 months and counting.

A short history of volcano eruptions in Iceland

Here is a short list of known eruptions in Iceland since the year 900 (or around that time). There might be missing eruptions because of lack of historical data. This list might not be completed from the reference that I am using.

Year of eruption

Year ~870. Ash and lava flow eruption in Vatnaöldum. Settlers ash layer is created in Iceland.

Year ~900. Creation of a lava field named Afstapahraun.

Year ~900 – ?. Somewhere in Vatnajökull glacier.

Year ~900. Krafla volcano erupts.

Year ~900. Hallmundarhraun lava field is created.

Year ~900. Rauðhálshraun lava field in Hnappadal is created.

Year ~905 – ?. Somewhere in Vatnajökull glacier.

Year ~920. Somwhere on the Reykjanes ridge. Location is unknown. But a ash layer is known from this eruption.

Year ~920. Katla volcano eruption. Ash layer named Katla-R.

Year ~934. Katla volcano creates Eldgjá volcano fissure. Lava flow from Eldgjá volcano fissure flows over Álftaver, Meðalland and Landbrot. Mýrdalssandur is sad to have been created in this eruption by a big flood from Mýrdalsjökuli following this eruption.

Year ~940. In Vatnajökull glacier or in Veiðivötnum. Ash from this eruption has been found in north-east Iceland.

Year 999 or 1000. Svínahraun lava field is created in a volcano eruption.

Year ~1000. Katla volcano eruption. Ash layer has been found. There is a written account of the flood that followed this eruption.

Year ~1060. Somewhere in Vatnajökli glacier.

Year 1104. Hekla volcano erupts it’s first documented eruption in Iceland. This eruptions sends ash to north and north-east. The valley of Þjórsárdalur is destroyed by volcano ash in this eruption.

Year 1151. Krýsuvík volcano erupts. This eruption creates the lava field Ögmundarhraun and Kapellahraun lava field. Trölladyngja is also created in this eruption.

Year 1158. Eruption in Hekla volcano.

Year ~1160. Somewhere in Vatnajökull glacier.

Year 1160 – 1180. Eruption on the Reykjanes Ridge. Two eruptions on the Reykjanes Ridge. Ash layer is known from this eruption.

Year 1179. Katla volcano eruption. Written accounts are unclear. But ash from this eruption has been found in Greenland glacier.

Year 1188 – ?. Rjúpnadyngjuhraun and Mávahlíðarhraun lava fields are created.

Year 1206. Hekla volcano erupts.

Year 1210 – 1211. Volcano eruption on the Reykjanes Ridge. Eldey is created in this eruption.

Year 1222. Hekla eruption.

Year 1223. Volcano eruption on the Reykjanes Ridge. Location unknown.

Year 1225. Volcano eruption on the Reykjanes Ridge. Location unknown.

Year 1226 – 1227. Several volcano eruptions on the Reykjanes. The following lava fields are belvied to have been created in this eruption, Younger Stampahraun, (Klofningahraun), Eldvarpahraun, Illahraun and Arnarseturshraun. At the same time a large ash eruption takes place at Reykjanestá. The middle age ash layer is created in this volcano eruption. This volcano eruption created a lot of problems for the local population.

Year 1231. Volcano eruption on the Reykjanes Ridge. Location unknown.

Year 1238. Volcano eruption on the Reykjanes Ridge. Location unknown.

Year 1240. Volcano eruption on the Reykjanes Ridge. Location unknown.

Year 1245. Volcano eruption in Katla volcano. This eruptions comes up at Sólheimajökli. Flood follows this eruption.

Year 1262. Volcano eruption in Katla volcano. This eruption is in Sólheimajökli. It creates a flood and is followed by a heavy ash fall.

Year 1300 – 1301. Hekla volcano eruption. A lot of ash fall in Skagafjöður, a famine followed this eruption due to ash fall.

Year 1311. A volcano eruption in Katla volcano. Heavy ash fall in east of Iceland (austfjörðum). A big flood followed this eruption, it was most likely on Mýrdalssandi. But written accounts are unclear and unreliable on what did happen.The following year was followed by a famine with death of both people and animals due too volcano ash.

Year 1332. A volcano eruption in Vatnajökli glacier. Most likely in Grímsfjall volcano.

Year 1340 – ?. Eruption in Brennisteinsfjöllum volcano. But no lava field from 14th century have been found however.

Year 1341. Hekla volcano eruption. Heavy ash fall. The ash did go to Borgarfjörð and Akranes. A lot of animal did die. Many farms in Rangárvöllum where abandoned following this eruption.

Year 1341 – ?. Grímsfjall volcano erupts.

Year 1354 – ?. Grímsfjall volcano erupts.

Year 1357. A large eruption in Katla volcano. A lot of damage.

Year 1362. A large eruption in Öræfajökull volcano. It did destory the county of Litla-Hérað and most likely all people how lived there did die. Most of the ash fall was into the ocean. But some of it did go to Hornafirði and in Lónshverfi. A glacier flood did go down Skeiðársand and out to the ocean.

Year 1372. North-west of Grímsey.

Year 1389 – 1390. Around Hekla volcano. Several farms did go under lava field in this eruption.

Year 1416. Eruption in Katla volcano.

Year 1422. Eruption somewhere off the Reykjanes. Creates a island that lasts for few years.

Year 1440. Eruption in or around Hekla volcano.

Year 1477. Volcano eruption on a long fissure in Veiðivötnum lakes and it reaches the western part of Vatnajökull glacier.

Year ~1480 – ~1500. Katla volcano has eruption. Few written accounts of this eruption.

Year ~1500. Somewhere in Vatnajökli glacier.

Year 1510. A large eruption in Hekla volcano. This eruption creates the largest known historical lava field from Hekla volcano. A heavy ash fall too the south takes place. A lot of destruction in Rangarvallársýsla follows it.

Year 1554. A eruption South-West of Hekla volcano. This eruption lasts about six weeks. Created craters called Rauðubjallar and from them a lava field called Pálssteinshraun.

Year 1580. Katla volcano erupts.

Year ~1582. Somewhere close to Eldey is a eruption.

Year 1597. A eruption in Hekla volcano started 3. January. Ash fall did happen but did not create a lot of damage.

Year 1598. Eruption in Grímsfjall volcano.

Year 1603. Eruption in Grímsfjall volcano.

Year 1612. Eruption in Katla volcano and Eyjafjallajökull volcano. A volcano eruption did start on 12. October in Katla volcano. But it unclear when the eruption did start in Eyjafjallajökull volcano.

Year 1619. Eruption in Grímsfjalla volcano.

Year 1625. Eruption starts in Katla volcano. The eruption started on the 2. September and it ended on the 25. September. This was a large eruption that did destroy 25 farms. Most the ash fall was to the east in this eruption. First report about volcano eruption is written in about this eruption.

Year 1629. Eruption in Grímsfjall volcano.

Year 1636 – 1637. Eruption in Hekla volcano starts 8. May and is ongoing for about one year. Little ash and little damage from this volcano eruption.

Year 1637 – 1638. Eruption somewhere in the neighbourhood of Vestmannaeyjar volcano.

Year 1638. Eruption in Grímsfjall volcano.

Year 1655. Eruption somewhere in Vatnajökull glacier. Most likely in Kverkfjöllum volcano. A large glacier flood took place in Jökulsá á fjöllum.

Year 1659. Eruption in Grímsfjall volcano.

Year 1660 – 1661. Katla volcano eruption did start on the 3. November and lasted over the new year. Not a lot of ash fall. But a large glacier flood. It did destroy the farm called Höfðabrekka.

Year 1681. Somewhere in Vatnajökuli glacier.

Year 1684 – 1685. Eruption in Grímsfjall volcano. A large glacier flood in Jökulsá á fjöllum. One man did die along with large number of livestock.

Year 1693. Volcano eruption in Hekla volcano. This eruption did start on the 13. February. A lot of the ash did go to north-west. The ash fall did create a heavy damage in the nearby area.

Year 1693. Katla volcano erupts.

Year 1697. Eruption somewhere in Vatnajökull volcano glacier.

Year 1702. Eruption somewhere in Vatnajökull volcano glacier.

Year 1706. Eruption somewhere in Vatnajökull volcano glacier.

Year 1711 – 1712. Eruption in Kverkfjöll volcano.

Year 1721. Eruption in Katla volcano. Heavy ash fall, volume of ash is estimated 1 km³ and large glacier flood follows this eruption.

Year 1724 – 1729. Krafla volcano eruption. This eruption creates the crater Víti when lava did flow into Mývatn.

Year 1725. Eruption somewhere in Vatnajökull volcano glacier.

Year 1725. Eruption takes place south-east of Hekla volcano.

Year 1726. Eruption somewhere in Vatnajökull volcano glacier.

Year 1727. Volcano eruption in Öræfajökull volcano. Three people did die in this eruption.

Year 1729. Volcano eruption in Kverkfjöll volcano.

Year 1746. Volcano eruption in Krafla volcano. Only one eruption documented.

Year 1753. Eruption takes place south-west of Grímsfjall volcano.

Year 1755 – 1756. A eruption starts in Katla volcano on the 17. October. A heavy ash fall that is estimated to have been 1,5 km³ drifts to the north-east and creates heavy damage in it’s path. A large glacier flood goes down Mýrdalssand. It flows mostly west of Hafursey. Two men die due to lightning strike. About 50 farms where abounded temporary due to this eruption.

Year 1766. Eruption in the western part of Vatnajökull glacier. Most likely in Bárðarbunga volcano.

Year 1766. Volcano eruption in Hekla volcano. The ash cloud drifts to Húnaþings counties and Skagafjarðar. Ten farms where abandoned following this eruption due to the ash cloud.

Year 1774. Volcano eruption in Grímsfjall volcano.

Year 1783. Eruption on the Reykjanes Ridge. Creates a new island named Nýey. It is not far from Eldey. But it disappears soon after it’s creation.

Year 1783 – 1784. Skaftáreldar take place. A long with a eruption in Grímsfjall volcano. Lava flows over a area of the size 580 km². Volcano gasses and did create famine and shortage of green grass for live stock around most of Iceland. Effects of this eruption was felt over in Europe and most of northern hemisphere.

Year 1797. Volcano eruption in Grímsfjall volcano.

Year 1807. Volcano eruption in Grímsfjall volcano.

Year 1816. Volcano eruption in Grímsfjall volcano.

Year 1821. Volcano eruption in Katla volcano.

Year 1821 – 1823. Volcano eruption in Eyjafjallajökull volcano. This eruption started on the 19. December and was mostly ash fall. A glacier flood did go down Markarfljót.

Year 1823. Eruption somewhere in Vatnajökull glacier.

Year 1830. Eruption takes place somewhere in the area of Eldeyjarboða.

Year 1838. Eruption in Grímsfjall volcano.

Year 1845 – 1846. Eruption starts in Hekla volcano on the 2. September. A lava flow covers 25 km² area. Heavy ash fall follows this eruption. The farm Næfurholt was moved following this eruption.

Year 1854. Eruption in Grímsfjall volcano.

Year 1860. Eruption in Katla volcano. This eruption is small.

Year 1861. Most likely a eruption in Grímsfjall volcano that year. But it is uncertain.

Year 1862 – 1864. A eruption starts on the 15 km long fissure north of Tungnaárjökuls. It creates a crater rows called Tröllagígar and a lava field called Tröllahraun. The volcano responsible for this eruption is Bárðarbunga volcano.

Year 1867. Volcano eruption in Grímsfjall volcano.

Year 1867 – 1868. Volcano eruption around or creates Mánareyjar.

Year 1872. Eruption somewhere in Vatnajökull glacier.

Year 1873. Volcano eruption in Grímsfjall volcano.

Year 1874. Askja volcano erupts. Eruption may have started in February, when steam clouds where first seen.

Year 1875. Askja volcano erupts. A lava eruption did start on 3. January. A caldera starts to form later in January following this eruption.

Year 1875. A 25 km long fissure opens 18. February and lasted until middle of August. This is believed to be a dike intrusion from Askja volcano that did get up to the surface.

Year 1875. The largest eruption in history of Iceland started on the 28. March and lasted for about 8 hours. In this eruption the crater Víti erupted and other caters. There was a heavy ash fall in east of Iceland. This did destroy many farms in the east of Iceland. The Askja lake was created in this eruption. Many other eruption where documented in the following months.

Year 1876. The eruption from Askja volcano is believed to have ended in that year.

Year 1876. Eruption somewhere in Vatnajökli glacier.

Year 1878. Eruption in Krakártindur east of Hekla volcano.

Year 1879. Eruption close to Geirfulgasker.

Year 1883. Volcano eruption in Grímsfjall volcano.

Year 1884. Somewhere around Eldey. Poorly documented.

Year 1885. Most likely a eruption in Grímsfjall volcano. But it is poorly documented.

Year 1887. Eruption in Grímsfjall volcano.

Year 1889. Eruption in Grímsfjall volcano.

Year 1892. Eruption in Grímsfjall volcano.

Year 1896. Eruption most likely south of Vestmannaeyjar volcano.

Year 1897. Eruption in Grímsfjall volcano.

Year December 1902 – June 1903. Eruption in Bárðarbunga volcano. Eruption possibly in Dyngjuháls, exact location is unknown.

Year 1902 – 1904. Eruption in Grímsfjall volcano.

Year 1905 – 1906. Eruption in Grímsfjall volcano.

Year 1908 – 1908. Eruption in Grímsfjall volcano.

Year 1910 June 18 – October 1910. Eruption in Loki-Fögrufjöll (Hamarinn volcano).

Year 1910. Eruption in Grímsfjall volcano. Ash fall is documented from June to November in east of Iceland.

Year 1913. Eruption east of Hekla volcano in a area named Mundafell / Lambafell.

Year 1918. Katla volcano erupts. This eruption started 12. October and did finish 5. November. The ash cloud did go up to 14,3 km high into the air. A large glacier flood did go down Mýrdalssand. People was in danger. A lot of live stock got lost.

Year 1921. Askja volcano. Small fissure eruption.

Year 1922. Askja volcano. Small fissure eruption.

Year 1922. Grímsfjall volcano started erupting in September. This eruption did finish in less then a month.

Year 1923. Askja volcano. Small fissure eruption.

Year 1923. Grímsfjall volcano eruption. Small eruption.

Year 1926. Askja volcano eruption. Creates a small island in Öskjuvatni lake.

Year 1926. Around Eldey. Boiling ocean reported for few hours.

Year 1927. Around Esjufjöll volcano. Minor eruption. A glacier flood from Breiðarmerkujökli glacier that killed one person.

Year 1929. Askja volcano eruption possible. But poorly documented and uncertain because of that.

Year 1929. Eruption in Kverkfjöll volcano. The volcano eruption was observed during the summer.

Year 1933. Minor eruption in Grímsfjall volcano.

Year 1934. Eruption started in the middle March and lasted until middle of April in Grímsfjall volcano.

Year 1938. Eruption in Grímsfjall volcano. Was on the north part of the caldera. But did not break trough the glacier ice.

Year 1941. Eruption might have taken place in Grímsfjall volcano.

Year 1945. Eruption might have taken place in Grímsfjall volcano.

Year 1947 – 1948. A eruption starts in Hekla volcano on the 29. March. The ash cloud goes up to 30 km. The ash cloud goes to the south. The lava flow had the size of 0,8 km³. Most of it did go the west and south-west from Axlargýg.

Year 1954. Possible eruption in Grímsfjall volcano.

Year 1955. Possible small eruption in Katla volcano. Small glacier flood from Mýrdalsjökli.

Year 1961. A fissure eruption started on the 26. October in Askja volcano on a 300 meter long fissure.

Year 1963 – 1967. Eruption in the Vestmannaeyjar volcano system. Surtsey island is formed south of Geirfulgaskeri. Few smaller island are also created. But disappear quickly.

Year 1970. Eruption in Hekla volcano started on 5. May. Most of the ash fall was to NNW and into Húnavatnssýslur. The eruption the mountain only lasted for few days. But the eruption in Skjólkvíum the eruption lasted for about two months.

Year 1973. A volcano eruption starts in Vestmanneyjar volcano. A 1600 meter long fissure opens close to the town of Vestmanneyjar. About the third of the town did go under lava and about 400 houses where destroyed. This created Eldfell and Heimaey did grow to the east.

Year 1975. Krafla volcano eruption starts on 20. December. A short fissure opens on close to Leirhnjúk.

Year 1977. Krafla volcano eruption starts on 27. April, it ends on 29. April.

Year 1977. Krafla volcano erupts. Eruption starts on 8. September, it ends on 9. September.

Year 1980. Krafla volcano erupts on 16. March.

Year 1980. Krafla volcano erupts. Volcano erupts starts on 10. July, it sends on 18. July.

Year 1980. Krafla volcano erupts. The eruption starts on 18. October and is to 23. October.

Year 1981. Krafla volcano erupts. The eruption starts on 30. January and it sends on 4. February.

Year 1981. Krafla volcano erupts. The eruption starts on 18. November. It ends on 23. November.

Year 1980 – 1981. Hekla volcano erupts. The eruption started on 17. August, it lasted until 20. August. The eruption did resume on the 9. April the year later (1981) and did most likely end on 18. April.

Year 1983. Eruption in Grímsfjall volcano in the end of May.

Year 1984. A most likely a minor eruption in Grímsfjall volcano.

Year 1984. Eruption in Krafla volcano. It starts on 4. September and it sends 18. September.

Year 1985. Most likely a minor eruption in Lokahrygg in Vatnajökli glacier. Harmonic tremor is recorded and a caldera forms in the glacier.

Year 1991. Eruption starts in Hekla volcano on the 17. January. The power of the eruption quickly vanish. One crater remains active until 17. March. Little ash was in this eruption. Considerable amount of lava did flow south of Hekla volcano.

Year 1996. Eruption on a fissure between Bárðarbunga volcano and Grímsfjall volcano. This eruption started on 30. September on a 4 to 5 km long fissure. This eruption lasted until 30. October. The earthquake swarm did indicate the dike intrusion from Bárðarbunga volcano. Water that was melted in this eruption did flow to Grímsvatna in Grímsfjall volcano. The drain did happen on 5. November.

Year 1998. Volcano eruption in Grímsfjall volcano did start on 18. December. It lasted until 28. December.

Year 1999. Small volcano eruption takes place in Sólheimajökli glacier in the Katla volcano. Small glacier flood follows. The eruption does not break the surface of the glacier ice. This happens on 17. July. Earthquake swarm follows this event with largest earthquakes that are up to ML3.0 in size. Harmonic tremor is seen on seismometers around Katla volcano.

Year 2000. Eruption did start in Hekla volcano on the 26. February. It lasted until 8. March. Little ash did follow this eruption. Lava flow was not considerable large.

Year 2004. Eruption did start in Grímsfjall volcano on 4. November.

Year 2010. Eruption starts in Eyjafjallajökull volcano after a large earthquake swarm in it. The first phase of the eruption takes place in Fimmvörðuhálsi when a eruption starts there on 20. March. A eruption starts in the main crater on Eyjafjallajökull volcano on 14. April. A ash clouds follows it along with a glacier flood that goes down Markarfljót. Some damage takes place in this eruption the nearby area of Eyjafjallajökull volcano.

Year 2011. Largest eruption in 140 years Grímsfjall volcano start on May 21. It ended on May 25. The ash cloud coming from the eruption was the largest one in the past 140 years from Grímsfjall volcano. No glacier flood did take place in this eruption. The eruption started around 17:30 UTC. But the first steam cloud was not observed until around 18:32 UTC. The ash cloud did reach the hight of 20 km. But did soon drop down to 10 km. Three days after the eruption did start it did loose power at fast rate and was over on May 25.

Year 2011: Katla volcano had a subglacier eruption in July. This is the second eruption of the year 2011 in Iceland. A glacier flood followed this minor eruption of Katla volcano. The eruption started on 8th of July and ended on 9th July.

Year 2011: Hamarinn volcano might have (most likely) had a eruption week after Katla volcano. Glacier flood followed this minor eruption of Hamarinn volcano. The eruption ended 13 July. Total eruption time was around 12 to 14 hours.

Year 2014.

Bárðarbunga volcano

  • Two eruptions in the period of 16 – 22-August-2014. Exact time and date not known at the moment. Each eruption lasted for up to 24 hours at most.
  • Eruption 23-August-2014 under the glacier. Lasted for ~6 hours.
  • Eruption 29-August-2014 in Holuhraun. Lasted for ~4 hours.
  • Eruption 31-August-2014, it ended on 27-Februar-2015. It lasted for almost 6 months.
  • It is not clear how many minor eruptions have taken place under the glacier. Only documented eruptions are mentioned.

Year 2017

Katla volcano.
Start date: 29-July
End date: 29-July

A minor eruption took place in Katla volcano during the night of 29-July. It only lasted for 2 to 3 hours and was not visible and did not break trough the glacier. This eruption was only observed on harmonic tremor data from Icelandic Met office.


The minor eruption in Katla volcano as it appeared on harmonic tremor data on Icelandic Met Office SIL station. Copyright of this image belongs to Icelandic Met Office.

Before and after this even a small glacier flood appeared in Múlakvísl glacier river that comes from Mýrdalsjökull glacier. That glacier flood ended in the early mornings of 30-July-2017.
——-

This is the list of eruptions so far. It is not free of errors or typos. I am also going to update this list on a later date if I have to. As it is incomplete in regards to number of volcanoes mentioned in him.

Reference.

Eldgosaannáll Íslands (Wiki, Icelandic)
2010 eruptions of Eyjafjallajökull (Wiki)
Ármann Höskuldsson. „Hvert er öflugasta eldgos á Íslandi sem vitað er um?“. Vísindavefurinn 15.10.2010. http://visindavefur.is/?id=57031. (Skoðað 3.4.2011). (Icelandic)

Text is updated at 01:21 UTC on 4. April 2011. Error corrections to the list.
Text updated at 28. June 2011 at 22:34 UTC. Added Grímsfjall volcano eruption to the list.
Text updated at 28 September, 2011 at 12:56 UTC. Added Katla volcano eruption and Hamarinn volcano possible eruption to the list.
Article updated on 24-January-2015 at 00:57 UTC.
Article updated on 03-March-2015 at 15:14 UTC.
Article updated on 10-January-2016 at 19:19 UTC.
Article updated on 04-March-2016 at 03:00 UTC.
Article updated on 04-March-2016 at 03:08 UTC.
Article updated on 30-July-2017 at 20:18 UTC.
Article updated on 3-March-2019 at 00:24 UTC.

Deep earthquakes in Askja volcano. Data on how Japan Mw9.0 earthquake was recored in Iceland

I see that in last week (week 10) that there was a deep earthquake swarm that took place under Askja volcano. This time around the earthquake swarm lasted for about 75 seconds and the depth of this earthquake swarm was about 20 km. The location of the earthquakes was north-east of the main Askja caldera, but within the Askja volcano system it self. The largest earthquake last week in Askja volcano was ML2.2 in size. Last year there was also a deep earthquake swarm in Askja. But that time around it lasted for few hours, not second. That activity took place in Week 09 of the year 2010. Here is a map of that weeks activity. But this deep earthquake swarm suggests that magma is on the move under Askja volcano, as was the case in the year 2010 when a similar event did happen.

Above: Picture of the Vatnajökull glacier area. The deep earthquakes north-east of Askja volcano can be seen here.

Above: The 75 second earthquake swarm north-east of Askja volcano.

Japan Mw9.0 earthquake

Strong earthquakes like the Mw9.0 earthquake in Japan appear all over the world on seismometers. In fact the effect from this earthquake could be seen up to five days at least on long period seismometers. Icelandic Met Office did release in last week overview.

Above: How the earthquake did appear on the IRIS seismometer in Iceland.

Above: This is how the earthquake did appear on the SIL network. Aftershocks can also been seen in this plot.

Copyright of this pictures in this blog post belong to Icelandic Met Office or other parties unless I notice otherwise.

Blog post updated at 21:57 CET on 16.02.2011.