A new interferogram (InSAR) image of the magma intrusion beneath Reykjanes Peninsula was published yesterday.
The image depicts a series of multicoloured fringes centered between Fagradalsfjall and Keilir, resulting in a ground deformation between 28 June and 6 July.
Even though the deformation signal extends over a vast area of the peninsula, this doesn’t indicate a full-scale magma dyke beneath the region. The magma-filled dyke is situated between Fagradalsfjall and Keilir. Several small lineaments are also visible in the interferogram, which cut across the fringes. These represent fault movements/earthquakes that were triggered during the dike propagation. The maximum accumulated vertical deformation has increased to around 18 cm in the area in the NW direction.
About 4700 quakes have been monitored by the seismic instrument since the seismic swarm started on 4 July. 6 quakes during the past 24 hours were recorded with magnitudes of 3.5 or more, of which the strongest was reported to be felt in the SW region of Iceland.
The seismic activity is consistent with sequences in 2021 (February-March and December) and 2022 (July-August), caused by vertically propagating dyke injections.
Earthquakes are arranged in a northeast-southwest trending linear area between Fagradalsfjall and Keilir area, mostly concentrated north of Litli Hrútur mountain, and become shallower as magma continues to push its way towards the surface. As of the morning of 5 July, magma reached 2-3 km depth.
Due to the increased earthquake swarm, the Icelandic Meteorological Office (IMO) reported an increased risk of rockfalls in the area as the current hazard. People are advised to avoid steep slopes, cliffs and areas prone to collapse.
There are 7 webcams pointing at a potential eruption onset:
https://www.youtube.com/watch?v=_q1N4J5oTSE
https://www.youtube.com/watch?v=yJfiMhqLgTY
https://www.youtube.com/watch?v=aJP-8kLa3N0
https://www.youtube.com/watch?v=LMb66idO7DE
https://www.youtube.com/watch?v=uZGleOgreBY
https://www.youtube.com/watch?v=dPtOhow3KY0
https://www.youtube.com/watch?v=3uE8TEdK4C4
There are currently two possible scenarios to appear:
1. The activity may cease without eruption,
2. Based on the elevated seismic unrest, a likelihood of an impending eruption is considered high and is expected to occur within the upcoming hours to days