Category: Earthquakes

Posted on

Continued earthquake activity in Öræfajökull volcano

Earthquake activity continues in Öræfajökull volcano. There is a small drop in earthquake activity every few hours just before it increases again. This seems to be normal for earthquake like Öræfajökull volcano. The magma in Öræfajökull volcano is expected to be rhyolitic in nature. That explains the nature of the earthquakes swarms that are now taking place.


The earthquake activity in Öræfajökull volcano for the last 48 hours. Copyright of this image belongs to Icelandic Met Office.

Largest earthquake in last 48 hours had the magnitude of 1,7. At the moment larger earthquakes have not yet happened in last few weeks (since the magnitude 3,5 earthquake took place). The earthquakes at the outline and some distance from Öræfajökull volcano seems to be fault lines that move as Öræfajökull volcano continues to inflate. There is some risk of earthquakes at those locations, it is my view that risk is mostly minimal for now at least. I don’t know how the development has been for the cauldron in Öræfajökull volcano caldera since I haven’t seen any news about the development of that area.

Donations

Please remember to support my work with donations. Everything helps and prevents me from going completely broke in December. Thanks for the support. 🙂

Posted on

Slow increase in earthquake activity in Öræfajökull volcano

There seems to be a slow increase in earthquake activity in Öræfajökull volcano. For the last 48 hours the number seems to be rising. This is how it looks on this graph from Icelandic Met Office.


Earthquake activity in Öræfajökull volcano from 2005 – today. Copyright of this image belongs to Icelandic Met Office.

This increase in earthquake activity suggest that more magma is pushing up the volcano at faster rate. The main idea now is that the magma that is pushing up Öræfajökull volcano is rhyolite in nature and that seems to be confirmed to an extent by the earthquake activity as it now appearing.


Last 48 hours of earthquake activity in Öræfajökull volcano. The volcano is located in south part of Vatnajökull glacier. Copyright of this image belongs to Icelandic Met Office.

How this develops is a big question due to lack of accurate historical accounts. What is known about the eruption in 1362 was written down up to two centuries later and when that happens lack of accuracy is passed into the written record. The written record for the eruption in 1727 – 1728 is slightly better but is far from being accurate.

Donations

Please remember to support my work with donations. I am a bit broke in December due the long term problem with my finances (November was awful!). I hope for improvements in the year 2018. It also costs to run this website. Thanks for the support. 🙂

Posted on

Magma movement in Askja volcano (Dyngjufjöll)

For the past few days there has been a earthquake activity in Askja volcano. All of the earthquakes so far have been small in magnitude and only few have reached magnitude above 1,0. This earthquake activity is due to magma movements and its the first time I have seen it reported at this shallow depth (above 10 km depth).


Earthquake activity in Askja volcano. North of Vatnajökull glacier. There is also activity in Herðubreið to the east, but that’s an unrelated activity and is due to tectonic forces in the area. Copyright of this image belongs to Icelandic Met Office.

There are no clear signs that an eruption is about to happen in Askja volcano or in Dyngjufjöll as this area is also called. If an eruption starts in this area outside of any major water area its only going to erupt lava with minimal risk. Explosive eruption due to water is also a possibility but those are impossible to predict.

Posted on

Two magnitude 3,9 earthquakes in Bárðarbunga volcano

Today (21-November-2017) at 13:53 and 13:55 UTC two magnitude 3,9 earthquakes happened in Bárðarbunga volcano. This earthquake activity was in the regular area in the north-east part of the Báðarbunga volcano caldera. It remains to be seen if there is any change in conductivity in Jökulsá á Fjöllum following this earthquake swarm.


Earthquake activity in Bárðarbunga volcano today (green stars, red dots). Öræfajökull volcano is quiet today (maybe due to extremely bad weather in this part of Iceland at the moment). Copyright of this image belongs to Icelandic Met Office.

The aftershocks form a interesting line that goes east to west in the caldera. I’ve not seen that form before and it’s interesting to see it. I don’t know yet if it means anything besides a possible fault in the volcano. It takes the glacier water 9 hours to reach the monitoring station at Jökulsá á Fjöllum, Grímsstaðir from the one at Upptyppingar. I don’t know how long it takes the water to reach Upptyppingar from the glacier, it is at least several hours.

—

Please note that with current high activity I’m getting a bit stressed out with the workload when a lot of things are happening in short period of time.

Current list of unrest volcanoes is this.

Bárðarbunga (continued in September 2015 after the August 2014 – February 2015 eruption)
Öræfajökull
Katla
Askja (deep magma activity, not a major concern at the moment)

Other volcanoes are not a concern until they erupt without warning.

Posted on

Update on Bárðarbunga volcano and high conductivity in Jökulsá á Fjöllum glacier river

Conductivity remains rather high in Jökulsá á Fjöllum as it has been doing since before 14th of November. The source remains at Bárðarbunga volcano. The conductivity has slowly been getting lower since it peaked before 14th of November (I’m not sure when the peak was). Yesterday (18-November) I did notice the news a little discussion about Bárðarbunga volcano. It was stated that at least one cauldron in the glacier above Bárðarbunga volcano is so hot that is makes a steam trough the glacier. I have also not hear any other details about the reason why conductivity remains rather high in Jökuls á Fjöllum glacier river from the observations yesterday.

The steaming hydrothermal systems means there is a considerable energy in Bárðarbunga volcano system at the moment. This also invites the risk that next eruption cycle in Bárðarbunga volcano is going to large. This also increases the risk of small eruptions that are also hard to detect and might not break the glacier surface, unless they happen close to one of the new hydrothermal areas.


Earthquake activity in Bárðarbunga volcano in the last 48 hours. Copyright of this image belongs to Icelandic Met Office.

When next eruption cycle starts in Bárðarbunga volcano is impossible to know.

Posted on

Uncertainly level declared for Öræfajökull volcano, aviation code moved to yellow alert

Yesterday the Department of Civil Protection and Emergency Management declared uncertainty level for Öræfajökull volcano. Aviation colour code was also moved up to yellow alert level (can be viewed here).

Current status is that a ice cauldron has formed in the centre of the Öræfajökull volcano caldera. It is about 1 km wide and around 21 to 25 meters deep according to early measurements. This is the first time in documented history that such ice cauldrons has formed in Öræfajökull volcano. It is now believed that the ice cauldron has been emptying it self all week resulting in smell of sulphur in Kvíá glacier river. The glacier river can be viewed here on Google Maps Street View. Currently there is not a lot of earthquake activity happening in Öræfajökull volcano. This is to be expected (I guess). It is also worth noting that Öræfajökull volcano did do in few months what took Eyjafjallajökull volcano 16 years to do until an eruption happened.

There is not a lot of details on earlier eruptions from Öræfajökull volcano. Earliest eruption to our in time took place between 1727 and until 1728 (289 years). Before that an eruption took place in 1362 (655 years) and lasted for five months. Currently I don’t have a lot of information about the current status. This is due to lack of measurements as it was not expected that Öræfajökull volcano would do this even if earthquake activity was happening in the volcano. It was only from October (it seems) that it was figured out that something was going on in Öræfajökull volcano.


No earthquake activity in Öræfajökull volcano during the past 48 hours (blue dot in the south part of the image). Copyright of this image belongs to Icelandic Met Office.

Images of the new ice cauldron can be found here on Icelandic Met Office website.

I’ll post new information in this article as needed. If anything major happens I’ll write a new article.

Article updated at 16:26 UTC. Added information that I forgot.

Posted on

High conductivity in glacier rivers coming form Mýrdalsjökull glacier (Katla volcano)

During the last few days there has been high conductivity in glacier rivers coming from Mýrdalsjökull glacier (Katla volcano). Due to how cold it is the glacier rivers are not getting any melt water or water from clear streams and that is making the hydrothermal water stronger than normal. Current conductivity is 567µS/cm in Múlakvísl in Mýrdalssandur sand area (not sure where the sensor is located). Some gas has also been detected and that gas is toxic and enough amount to result in breathing problems. Measured amount of H2S was 1ppm and this gas is toxic.

Some minor earthquake activity has been in Katla volcano during the last two days. That earthquake activity might be due to the emptying of the cauldrons in Mýrdalsjökull glacier. The magnitudes in this earthquake activity is minor and all below 2,0 at the moment.


Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

It is difficult to know if this means anything other than cauldrons in the glacier emptying them self in nearby glacier rivers.

Posted on

Magnitude 3,4 earthquake in Tjörnes Fracture Zone during the night

At 01:01 UTC on 18-November-2017 there was a magnitude 3,4 earthquake in western part of the Tjörnes Fracture Zone. A foreshock of magnitude 2,2 occurred at 00:30 UTC. Only this two earthquakes happened at this location north of Siglufjörður village.


The earthquake activity in TFZ during the night. Copyright of this image belongs to Icelandic Met Office.

The larger earthquake was felt in Siglufjörður village.

Posted on

Sulphur smell from Kvíá glacier river that comes from Öræfajökull volcano

Today (16-November-2017) it was reported that sulphur smell was felt from a glacier river that comes from Öræfajökull volcano. The glacier river in question is called Kvíá and is a small and short glacier rivers on the south side. Currently there are no conductivity measurements on the glacier rives that comes from Öræfajökull volcano. The plan is that such measurements are going to start soon around Öræfajökull volcano. Along with gas measurements.

This change suggests that a hydrothermal systems have opened up somewhere under the glacier in Öræfajökull volcano. This means that magma has now reached depth of 1 km or less. For the past few days the earthquake activity in Öræfajökull volcano has been getting lower then during the last few weeks when up to 50 earthquakes was being recorded during each week. Earthquake activity continues today, but at much lower rates than before at the moment.

I’ll post updates about this as more information is reported.

Icelandic news in Icelandic

Brennisteinslykt við Öræfajökul (Rúv.is, Icelandic, map of the area)
Rannsaka brennisteinslykt við Kvíá (Vísir.is)

Article updated at 17.11.2017 at 00:44 UTC. Minor text title fixes.

Posted on

One magnitude 3,7 earthquake in western TFZ

Yesterday (13-November-2017) at 07:36 UTC a magnitude 3,7 earthquake took place in western Tjörnes Fracture Zone. There where no aftershocks following this earthquake or any other earthquake activity.


The magnitude 3,7 took place where the green star is. Copyright of this image belongs to Icelandic Met Office.

There is not much else to say about this earthquake since no other earthquake took place following it. It was felt by local people.