Volcano and earthquake activity in Iceland
Today (28-July-2021) at 12:36 UTC an earthquake with magnitude of Mw3,1 took place in Katla volcano caldera. Few smaller earthquakes have followed the largest earthquake.
This looks like a normal summer earthquake activity in Katla volcano. If that changes is impossible to know. There is no change in harmonic tremor on SIL stations around Katla volcano.
After a long while of not writing about Bárðarbunga volcano it is now time for new article.
On 27-July-2021 at 19:02 UTC an earthquake with magnitude of Mw3,9 took place in Bárðarbunga volcano. At 22:12 UTC an earthquake with magnitude of Mw4,5 took place in eastern part of Bárðarbunga volcano. EMSC is reporting this earthquake as mb4,8. That information can be found here.
This earthquake activity in Bárðarbunga volcano is because there is now inflation going on in Bárðarbunga volcano. This inflation is going to continue until there is a new eruption. When that happens is impossible to know.
Today (26-July-2021) at 16:35 UTC an earthquake with magnitude of Mw3,0 took place in Ljósufjöll volcano. Earlier earthquake with magnitude of Mw2,2 also took place at 15:44 UTC.
In this area there is also a fault zone that is between Langjökull and Snæfellsnes. That fault zone normally doesn’t have many earthquakes. With only activity happening every few decades and sometimes even less frequency. The area where the earthquake activity is inside the volcano named Ljósufjöll. Earthquake activity in this area started in May-2021. Currently its too early to know if this means anything, since this might just be earthquake activity and nothing more might happen, even if this earthquake activity is happening in a volcano.
Since yesterday (24-July-2021) and until today (25-July-2021) there has been rather strong earthquake activity in Katla volcano. The earthquakes are not strong with largest earthquakes having a magnitude of Mw2,6. It is unclear what is going on.
One of the reasons this earthquake activity is happening is that cauldron might be emptying in the Mýrdalsfjökull glacier. That creates a drop in pressure that can start earthquake activity. I don’t know if that is what happened now. If that is what is going on it is going to take the melt water few hours to reach the rivers in Mýrdalssandur sand area. There has not been any change in harmonic tremor activity following this earthquake activity.
Since 22-July-2021 there has been an earthquake activity in Katla volcano. This earthquake activity has been mostly located to the east of the caldera and largest earthquake so far detected had a magnitude of Mw3,0.
There has not been any change in harmonic tremor activity following this earthquake activity. That strongly suggest that this is normal summer earthquake activity for Katla volcano. Earthquake activity is also far too low for it to signal any eruption risk. That might change if earthquake activity changes and grows in size.
Early morning of 11-July-2021 an earthquake swarm took place north of Grindavík town. Largest earthquake in this swarm had a magnitude of Mw2,5. Most of the other earthquakes had a magnitude of Mw0,0 to Mw1,0. There was also an earthquake swarm on Reykjanestá area that is part of Reykjanes volcano.
It is difficult to know for sure what this earthquake activity means for this volcano. Since it has already been proven that eruption activity can start on Reykjanes peninsula without any warning or earthquake activity. Currently there are no clear indicators that suggest anything is about to happen but that can change without warning.
Donations
Please remember to support my work with donations. Thanks for the support. 🙂
On 24-May-2021 at 21:36 UTC an earthquake took place in Brennisteinfjöll volcano. The magnitude of this earthquake was Mw3,6 and this earthquake was felt in Reykjavík area.
There have been few smaller earthquakes in this area since the largest earthquake, but other than that it has been quiet. This earthquake is believed to have happened because of stress changes on the Reykjanes peninsula because of the eruption in Fagradalsfjall mountain.