This is a short update on the activity in Krýsuvík volcano. The activity has been confirmed to be only in Krýsuvík volcano and nothing is currently happening in Reykjanes volcano at the writing of this article.
Krýsuvík volcano started to show changes in late 2008 and early 2009 and that has been going on since then in low activity. Krýsuvík volcano is strange in that it does not have any shallow magma chamber in the top layers of the crust and Krýsuvík volcano size is unclear. This uncertainty shows in maps as different maps show different size and location of Krýsuvík volcano. While there is no shallow magma chamber in Krýsuvík volcano it does not rule out a deep, large magma chamber that does not show up on any seismometer since this magma chamber is located in the top layers of the mantle (10 to 30 km).
Largest earthquakes since midnight had a magnitude of Mw4,6 and since around 12:00 it has been rather quiet in Krýsuvík volcano when it comes to large earthquakes. A lot of smaller earthquakes have been taking during all this time and there is no sign of those stopping. The reason for all this earthquake activity is a magma dyke that is now breaking its path up to the surface from around 10 km depth. There are nothing to suggest that process is about to stop or slow down. Drop in activity as is now happening are common feature of this type of dyke activity and was seen just before the eruption in Bárðarbunga volcano (Holuhraun) in 2014 to 2015.
Earth Science department of University of Iceland released a pictures that show how this dyke in Krýsuvík volcano works and that image can be viewed here on Facebook.
If anything major happens I am going to post an update soon as possible. Next update is tomorrow (03-March-2021) if activity remains as it currently is.
Article updated at 20:25 UTC. Fixes in the text.