Donation notice: If you can donate please do so. It helps me run this website and keeping up my work here. Information on how to donate can be found here. Thanks! 🙂
Few years ago there was an strong earthquake swarm 45 km north of Grímsey island, the earthquake swarm location was between Grímsey island and Kolbeinsey island. The strongest earthquake in that swarm had the magnitude of 5,5. It’s now considered a possibility that an minor eruption took place at this location when this earthquake swarm took place in the year 2002. This is according to an recent study into the volcano activity in this area. Since this part of the rift zone where volcanic activity continues where the Tjörnes Fracture Zone ends.
This volcano is located at depth at this location so any minor eruption is not going to get noticed on the surface of the ocean.
The earthquake swarm in this area in the year 2002 (vedur.is, Icelandic, images). Earthquakes larger than 3,0 are marked by green dots. Copyright on this image belongs to Icelandic Meteorological Office.
Icelandic News about this. Beware Google Translate.
Við misstum af síðasta eldgosi við Norðurland (Vísir.is, Icelandic)