During the night and today (18. December 2022) the earthquake swarm around 47 km east of Fonti in Eastern Iceland continued. Largest earthquake at the writing of this article had magnitude of Mw3,3 but another and few smaller earthquakes, but with magnitude of Mw3,1 took place in the same location. Several earthquakes with magnitude above Mw2,5 also took place.
This is a inner plate earthquake activity. This type of earthquake activity happens infrequently in Iceland. When it happens it can get rather strong and long period of earthquake activity can take place. It is not known what is in this area. Its either an extinct volcano (re-activated faults connected to that extinct volcano) or an old fault zone that is now re-activated for some time. The crust in this area is 15 million to 24 million years old and possibly older.
I am expecting more earthquake activity in this area. This earthquake activity might stop as quickly as this earthquake activity started.