Category: Volcano

Posted on

The dormant volcanoes in Iceland

While all the active volcanoes in Iceland get all the press and coverage. There are volcanoes in Iceland that are not so active and have remain dormant for thousands of years now and currently do not show any signs of activity. Some have some hot spring activity. But that is about it for them. The following volcanoes in Iceland have not erupted in historical times. Some have not even erupted in past 12.000 years best to my knowledge. But as history has proved in other parts of the world. An dormant volcano can start to erupt when it feels like it and without any warning at all in some cases.

This is based on Global Volcanism Program data. So it might be subject to errors and updates.

Volcano

Hrómundartindur – Last eruption is unknown. This volcano is an stratovolcano.

Grensdalur – Last eruption was in Pleistocene and its current status is Pleistocene-Fumarolic. This volcano is an stratovolcano.

Grímsnes – Last eruption is believed to have taken place around 3500 BC. But this volcano is marked as tephrochronology. This volcano makes crater rows when it erupts.
Geysir – This volcano last erupted in Pleistocene and is marked as Pleistocene-Geysers. This is an stratovolcano.

Hveravellir – This volcano last erupted around the year 950 AD. It is currently marked as radiocarbon. This is an subglacial volcano.

Hofsjökull – This volcano has erupted sometimes in the last 12.000 years. It has the marking holocene. This is an subglacial volcano. The second volcano in this system is not marked in GVP database. But that volcano is named Kerlingarfjöll. I do not know when it last erupted. There is also an embeeded second volcano in Hofsjökull volcano that is Independent from the main Hofsjökull volcano (yes, this is the case it seems). I do not have any idea when that did last erupt.

Esjufjöll – This is an sub-glacier volcano in Vatnajökull glacier. Its last eruption is uncertain. But is believed to taken place in the year 1927. From the year 2000 this volcano has been showing signs of increased activity. This volcano is an stratovolcano.

Fremrinamur – This volcano is last believed to have erupted in the year 1200 BC. This volcano is an stratovolcano.

Þeystareykjabunga – This volcano last erupted around the year 900 BC. This volcano is an shield volcano.

Snæfellsjökull – This volcano last erupted around 200 AD. It is currently marked as radiocarbon. This is an stratovolcano.

Helgrindur (also known as Lysuhóll) – This volcano has no record of eruption. But it is thought that it erupted sometimes in the past 12.000 years. But exact time is not known. This volcano makes pyroclastic cones. This volcano is the smallest volcano system in Iceland.

Tindafjallajökull – It is unknown if this volcano has erupted during holocene. But the GVP information say that dozen of small eruptions took place in early holocene. This is an stratovolcano.

Snæfell – This volcano is located east of Vatnajökull glacier and south of Kverkfjöll volcano. It was once believed that this volcano was extinct. But new research into it has changed that opinion. This is most likely an stratovolcano. But I do not have it confirmed. This volcano has at least not erupted for several thousands years or more. Currently there are no information about this volcano in the Global Volcanism Program database.

Skrokkalda – This volcano is dormant. But I do not know if it has erupted in historical times or not, but I do no think that is the case. I am also not sure what type of volcano it is.

There are few more volcanoes missing due the fact that they are not in the Global Volcanism Program database. But I have them on a map that I own. So they are going to be added later when I update this blog post.

Posted on

Harmonic tremor continues to drop in El Hierro volcano

It seems that currently the eruption in El Hierro volcano is coming to an end. I do not know if this is an permanent end to the current eruption or just an short break in it. The reports that I have seen so far suggest that the main crater out of the coast of La Restinga has stopped erupting. The current harmonic tremor however suggests that an eruption is still taking place somewhere. But I have no idea where that might be at current time, and so far no clues where that might be. But the lack of earthquakes north of El Hierro Island suggests that an eruption might be taking place there. But that is just speculation.


The harmonic tremor in El Hierro volcano at 20:36 UTC. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

Other then this. There is not that much to report from the eruption in El Hierro volcano, or what is left of it at current time. If there are any major changes. I am going to report them soon as I can. But at current time. It does not look like there is isn’t a lot needed to be reported on the eruption in El Hierro volcano.

Posted on

More man made earthquakes in Hengill volcano

Since 04:49 UTC this morning (17 December, 2011) there has been an earthquake swarm in Hengill volcano. This earthquake swarm is due to hydro-thermal power production that is currently taking place in this area. But the Orkuveita Reykjavíkur (OR) is obligated to pump down cold water into the bedrock at depth that is greater then 800 meters. This water is used hot water that they pump up from the ground to warm houses and make electricity.


The earthquake swarm at 12:45 UTC on 17 December, 2011. Copyright of this picture belongs to Iceland Met Office.


The evolution of the earthquake swarm since it did start. Copyright of this picture belongs to Iceland Met Office.


The earthquake swarm as it did appear on my geophone at Heklubyggð. But the geophone at Eyrarbakki is scheduled to be up and running in next week. This picture is released under Creative Commons licence. See top bar for more information under CC Licence.

The earthquake swarm in Hengill volcano is currently ongoing. So far the largest earthquakes have had the size ML2.1 according to the automatic SIL system. Due the high number of earthquakes, the earthquakes have been wrongly placed on the map of Iceland that Iceland Met Office has. This are not real earthquakes in most cases, just wrongly located earthquakes that are taking place in Hengill volcano. The earthquake swarm is currently ongoing. If there are any major changes to this earthquake swarm. I am going to update this blog post with information about it.

Posted on

Short overview of volcano eruptions in Canary Islands

Here is an short overview of volcano activity in Canary Islands during the past 1000 years. But I do not want to go any more back in time. But this is similar to what I did about Iceland few months ago. For refrence I am using Global Volcanism Program data. I do not have any other data point at the moment. This blog post is going to be updated as more eruptions takes place. This is the same thing that I do with historical overview about volcano eruptions in Iceland.

Year of eruption

Gran Canaria has not had any eruption in past 1000 years.

Fuerteventura has not had any eruption in past 1000 years.

Year ~1060, eruption starts in Tenerife.

Year ~1480 eruption takes place in La Palma.

Year 1492, eruption starts in Tenerife on ~24 August.

Year 1585, May 19. Eruption starts in La Palma. It lasts until 10 August.

Year 1646, eruption starts on 2 October in La Palma. It lasts until 21 December.

Year 1677, eruption starts on November 17 in La Palma. It lasts until 21 January 1678.

Year 1704, eruption starts in Tenerife on 31 December. It last until 27 March in the year 1705.

Year 1706, eruption starts in Tenerife on May 5. It lasts until 13 June.

Year 1712, eruption starts on October 9 in La Palma. It lasts until 3 December.

Year 1730, eruption starts on September 1 in Lanzarote. It lasts until April 16 in the year 1736.

Year 1798, eruption starts in Tenerife on June 9. It lasts until ~14 September.

Year 1824, eruption starts in Lanzarote on July 31. It lasts until 24 October.

Year 1909, eruption starts in Tenerife on November 19. It lasts until November 27. It lasts until November 27.

Year 1949, eruption starts on June 24 in La Palma. It lasts until 30 July.

Year 1971, eruption starts on October 26 in La Palma. It last until November 18.

This blog post is going to be updated regularly.

Blog post updated at 20:55 UTC. Fixed some errors in the text.

Posted on

Update on the eruption in El Hierro volcano (13 December, 2011)

Here is a long overdue update on the eruption in El Hierro volcano. But the eruption in El Hierro volcano is now in its third month.

Overall there has not been a lot of change in the eruption that is taking place in El Hierro volcano. But from what I can gather the eruption is taking place in just one vent at the moment. But that is common with this type of eruption. As they start with an fissure, but they end up just one vent erupting and building an cinder cone. Currently the eruption is taking place underwater. But that does not stop it from building an cinder cone. If the eruption continues long enough it is going to form an new island in this location. If that happens, the eruption is going to go from ash making eruption and down to lava eruption. Islands that form in this type of eruptions stand an better chance of lasting more then few months in the ocean. As the eroding powers of the ocean can wipe out a new Island in matter of months if it is just made out of volcanic tuff material.


Current harmonic tremor in El Hierro volcano eruption. The spikes are believed to be explosions taking place in the eruption area. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


Steam event taking place in the eruption of El Hierro volcano. This picture is from 4 December, 2011. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

There is also an other event that has mostly gone unnoticed by people. But that is the fact that earthquakes have stopped in north part of El Hierro volcano, current rate of earthquakes is close to zero during 24 hour period. This strongly suggests that an eruption has started in north part of El Hierro volcano. I have no idea where it, as there are no signals at the surface of the ocean that give clues to where this eruption might be taking place. But an similar drop in earthquakes took place just after the eruption in south El Hierro volcano started. The depth in north part of El Hierro Island increases sharply and any eruption that is currently taking place on more depth then 1000 meters is going to be hard to impossible to detect properly.

I am going to continue to monitor the eruption in El Hierro volcano. If there are any major changes. I am going to report it soon as I can do so.

Posted on

Earthquake activity continues in Katla volcano

Even if it is December and Mýrdalsjökull glacier has added around 6 meters of snow on top of it self. It seems that the earthquake activity in Katla volcano is rather strong, even if it winter already in Iceland.


Earthquake activity in Katla volcano past 48 hours. Some of this earthquakes might be frost-quakes due the freezing weather in Iceland for the past few days. Copyright of this picture belongs to Iceland Met Office.

The earthquake activity in Katla volcano is resistant in the Katla volcano caldera and has been that for several weeks already. I cannot interpreted this earthquake activity other then Katla volcano is preparing for an eruption. But when I am not sure at this moment. There is an pattern of earthquakes in Katla volcano caldera, this pattern has been in place since Week 27, but that is the week when the minor eruption took place in Katla volcano caldera last summer (summer 2011).

It is clear that this earthquake activity in Katla volcano is going to continue. I am assuming that this earthquake activity is going to continue until a eruption takes place in Katla volcano. But there is also the chance of the year 1999 event. When a small eruption took also place and earthquake activity remained high for several weeks after that. But after some time the earthquake activity started to drop. For the moment I find that to be unlikely outcome given how long the earthquake activity has remained high in Katla volcano after the minor eruption this summer.

Donations: I am going to try and setup the geophones in Eyrarbakki village and the geophone close to Katla volcano in December. But that trip is going to cost me some money (I pay for the car benzine), but the cost might go as high €157, 1169 DKK, $210, 25.000 ISK (current exchange rates) just for gas (on an car) for that trip. So if anyone can help with this cost it would be welcomed. Thanks for the support! 🙂

Update 1: I am most likely going with the bus. But that also costs some money, around 3900 ISK, 182 DKK, 24€. $32, 20GBP (Current exchange rates).

Blog post updated at 13:12 UTC on 12 December, 2011.

Posted on

Earthquake activity in Katla volcano

Even if there is December and Katla volcano is supposed to have less earthquake activity during this time of year. It seems to be that currently that is not the case. But the earthquake activity is less then it was this summer after the minor eruption in July 2011. No major earthquake swarm has been taking place in Katla volcano for the past few weeks. But there is a lot of earthquakes taking place, without it being a earthquake swarm at one single location inside Katla volcano.


Current earthquake activity in Katla volcano. Copyright of this image belongs to Iceland Met Office.

Many people might ask if this earthquake activity is something to worry about. The answer is no. Katla volcano is unlikely to start an eruption in December. But if this pattern of earthquake activity it is clear that Katla volcano is going to erupt sooner rather then later. But the question after the mini-eruption last summer (July 2011), if there are going to be around 10 years until next eruption takes place in Katla volcano. For the moment nobody knows for sure.

Other: I want to remind people about the forum. It can be used to ask questions, chat, share pictures and so on.

Posted on

Harmonic tremor in El Hierro volcano drops

There was a change in the eruption in El Hierro volcano last night. The harmonic tremor started to drop of slowly. This drop in harmonic tremor comes several days after a drop in earthquake activity happened. But it might be possible that this drop in earthquake activity in north El Hierro volcano might be because a erupting vent did open up in north El Hierro volcano. But at such depth that the eruption was not noticed on the surface on the ocean. At least that might be the reason. But without any data, this is just a speculation. But at any rate, the earthquake activity in north part of El Hierro volcano has dropped down to almost zero in few days time.


The harmonic tremor yesterday (5 December, 2011). The drop in harmonic tremor can clearly be seen here. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).


The harmonic tremor today at 08:15 UTC. The harmonic tremor continues to drop during the past few hours. Copyright of this picture belongs to IGN (Instituto Geográfico Nacional).

The harmonic tremor drop is something that has happened before in El Hierro volcano. Just before a new fissure did open up in El Hierro volcano eruption. I am unsure if that is the case now. But it should become clear in about two to three days. But it is also a possibility that this eruption is coming to a end. But it has been erupting now for close to three months now. So this eruption might just ending. But we might have to wait a bit until that is confirmed. But at the moment the harmonic tremor is dropping and that means the eruption is smaller for the moment.

Posted on

Harmonic tremor pulse in Grímsfjall volcano

There have only been seven months since (May 2011) the last eruption in Grímsfjall volcano. But it seems that Grímsfjall volcano is getting ready for its next eruption. Even if the last eruption was the largest one for at least 140 years in Grímsfjall volcano. So far earthquake activity remains low in Grímfjall volcano. But I am not sure if that means anything for the moment. But there has been in earlier lead up to a eruption a build up of earthquake activity in Grímsfjall volcano.

Today at least two harmonic tremors spikes have been detected by IMO. But this type of harmonic tremor pulse have been detected before in Grímsfjall volcano. Older blog posts on that subject can be found here and here. But this time around it seems that the harmonic tremor is stronger then before. Currently it remains uncertain of there is a glacier flood starting from Grímsvötn lake, as was the case last time this type of harmonic tremor pulse was detected in Grímsfjall volcano.


Harmonic tremor in Grímsfjall volcano at 00:21 UTC on 5 December, 2011. Copyright to this picture belongs to Iceland Met Office.


The harmonic tremor in Grímsfjall volcano at 01:39 UTC on 5 December, 2011. Copyright to this picture belongs to Iceland Met Office.

There is a clear change in the harmonic tremor, as can be seen here. But why and what this actually means for Grímsfjall volcano I am not sure. But I am rather sure that this means a new eruption might only be several months away. But it is hard to know that for sure. But I am just base my estimate on earlier experience with Grímsfjall volcano. But it might not mean anything after last eruption.


The GPS data from top of Grímsfjall volcano. The data is missing for the last few days. Must be because of snow and ice. But given the last data set, the change so far it not that great since the eruption last spring. Copyright to this picture belongs to Iceland Met Office.

What happens next in Grímsfjall volcano is a big question. But it seems that Grímsfjall volcano is going to go for a new eruption. When that might happen I have no idea.

Posted on

New media hype over Katla volcano

There apparently is a new media hype over Katla volcano in the British press. This time around it is from BBC News. The news in question claims that a eruption in Katla volcano is going to have a global impact. This is nothing but a exaggeration in my view. While a eruption in Katla volcano might be big, there effects are mostly localized to Iceland. This was clear during the Grímsfjall volcano eruption in May of 2011. Where the global effect was close to zero, there where some flight disruptions. But they where not something major like did happen during Eyjafjalljökull volcano eruption. So the media is overestimating the effects of eruption in Katla volcano. To what end I do not know. But it sure annoyed me, and the scientists that monitor volcanoes in Iceland.

It is also important fact that Katla volcano did have an eruption this year. It took place on 8 and 9th July, 2011. With a smaller eruption on the 10th of July, 2011. This eruption was however a small one and did only melt the glacier, as it was not strong enough to break trough the ice. My coverage of those events can be found here (the whole timeline of events can be viewed here).

In terms of effects of a large eruption in Katla volcano. One thing is clear. It is mostly going to local to Iceland, it might disrupt flights in Europe of the wind systems are unfavorable. Both over mainland Europe or for transatlantic flights. But transatlantic flight can in most case route around the ash clod if it they need to. But the claim for global effects are just exaggeration and nothing else.

The BBC News hype.

New Icelandic volcano eruption could have global impact