A small earthquake swarm took place in Tungnafellsjökull volcano during the night of 18-March-2017. All earthquakes that happened where minor in magnitude with many earthquakes having depth from 3 to 13 km.
The earthquake activity in Tungnafellsjökull volcano (yellow dots, north of Bárðarbunga volcano). Copyright of this image belongs to Icelandic Met Office.
It is not clear why this earthquake activity happened in Tugnafellsjökull volcano. This might be a dyke intrusion at depth or it might also just be a stress adjustment in the crust due to the inflation happening in Bárðarbunga volcano. It is not known at the moment if this is due to magma or stress adjustment in the crust. This is the first earthquake activity in Tungnafellsjökull volcano after considerable period of quiet.
The activity at Herðubreið appears to be intensifying, any word from IES?
No. At the moment it’s not enough to be a concern. If it starts getting significant enough to raise eyebrows (like at Katla in late September) then they’ll respond e.g. a yellow alert.