The Civil Protection and Emergency Management’s Science Board held an online meeting today in order to discuss the earthquake swarm in the Reykjanes Peninsula. The meeting was attended by specialists from the Icelandic Met Office, University of Iceland, Iceland Geosurvey (ÍSOR), the Environment Agency of Iceland, Icelandic Institute of Natural History, and Reykjavik Energy beside representatives from the Directorate of Health, Isavia-ANS and HS-Orka. Measuring and data that have been received the past 24 hours were reviewed at the meeting.
Main conclusions of the meeting
- Magma path continues to expand and the greatest magma flow is located at the southern end of it. While magma continues to flow into the path one has to reckon the likelihoods of an eruption in that area. The longer the present situation lasts the chances of an eruption increase. Very little chances are for that kind of eruption to threaten population.
- It is important to closely monitor the activity in the southern hills of Fagradalsfjall in order to see whether this activity is a signal that the magma path is expanding to the South.
- Interpretation of satellite images received this morning and the latest GPS measuring confirm that magma accumulation continues to be restricted at the southern end of the magma path that reaches from Keilir to Fagradalsfjall. That place continues to be considered the most likely place in case of an eruption.
- In case the magma path continues to expand and cause a tensity in the area, earthquakes can be expected that will be found in habituated areas, similar to the ones that have occurred the past few days.
Further on the conclusions of the meeting
Sharp earthquakes were detected in the southern hills of Fagradalsfjall last night and all day today and they are connected to changes in the southern-most part of the magma path. Also, a few tremors were detected just north of Grindavík, but the formation of the magma path causes changes in tensity in a big area, among others, west of Fagradalsfjall. The earthquake activity this morning has consisted of smaller quakes of about 2 in size. While the magma path fills up steadily a changeable and fitful seismic activity can continue to be expected. Interpretation of satellite images received this morning and the latest GPS measuring confirm that magma accumulation continues to be restricted at the southern end of the magma path that reaches from Keilir to Fagradalsfjall. That place continues to be considered the most likely place in case of an eruption.
GPS measures indicate that the magma flow has decreased a little bit, though the uncertainty in those measurements is considerable as the magma lies at a very shallow level in the earth’s crust (at the depth of approximately 1 km). However, it is the assessment of the Science Board that it is important to closely monitor the activity in the southern hills of Fagradalsfjall in order to see whether it is a signal that the magma path is expanding to the South.
Magma will not come up with great force in case of an eruption.
As the situation is assessed at present the magma lies at a very shallow level, at the depth of 1-1.5 km. It is important to realize that if magma breaks its way all the way to the surface, it can be expected that it could happen without much effort or seismic activity. Examples of such can be seen in the eruption that began in Fimmvörðuháls in 2010. Then no clear indication of the beginning of an eruption could be found in the measuring equipment of the Icelandic Met Office and it was news from witnesses that confirmed that magma had emerged. In this light the Icelandic Met Office has set up web cameras that can be utilized in order to monitor in case magma emerges.