A 4.2 magnitude earthquake shook Iceland’s Reykjanes peninsula last night, originating just west of the Blue Lagoon. Magma is collecting some 4-5 kilometres [2.5-3.1 miles] below the surface of the peninsula, not far from where three eruptions have occurred over the last three years. While those eruptions did not damage infrastructure or inhabited areas, this latest magma intrusion is close to Svartsengi Geothermal Power Plant, the town of Grindavík, and the aforementioned Blue Lagoon.
Earthquakes and deformation
An earthquake swarm began on the Reykjanes peninsula on the night of October 24 just north of the town of Grindavík. On October 27, the land in the area began to rise, indicating a magma intrusion in the earth below. No volcanic unrest has been detected and there are no signs an eruption is imminent. However, the Department of Civil Protection and Emergency Management has declared an uncertainty phase in the area due to the earthquake activity.
This is the fifth time that deformation has been measured at this location since 2020. None of the previous instances resulted in an eruption. In a notice, the Icelandic Met Office stated that earthquakes are expected to continue. The notice also warned travellers of the risk of rockfall from steep slopes.
Water and electricity supply could be impacted
Reykjanes residents receive their hot water, cold water, and electricity from the Svartsengi Geothermal Power Plant, located near the magma intrusion that has formed on Reykjanes. According to the CEO of HS Orka, which owns the power plant, an eruption at the site could make it difficult to supply residents with hot water. Representatives of HS Orka answered residents’ questions at a town hall meeting in Grindavík yesterday, along with Icelandic authorities and experts.
Kristinn Harðarson, HS Orka’s production manager, stated that the company is prepared to respond if an eruption does occur near Svartsengi. “We are well prepared as far as that goes, what can be done,” Kristinn stated at the meeting. “We are very well connected with working groups within the Department of Civil Protection who will work with us to protect the power plant in the event of lava flow. And every effort will be made to protect the power plant, if such an event were to happen.”