An Icelandic town near the capital Reykjavik and home to some 4,000 people was evacuated overnight after hundreds of tremors caused fears of a volcanic eruption, authorities said Saturday.
Iceland declared a state of emergency on Friday after a series of powerful earthquakes rocked the country’s southwestern Reykjanes peninsula, in what could be a precursor to a volcanic eruption near Sundhnjukagigar, some three kilometers (1.86 miles) north of the town of Grindavik.
The town — around 40 kilometers southwest of Reykjavik — is located near the Blue Lagoon geothermal spa resort, a popular tourist destination that closed temporarily earlier this week as a precaution.
Grindavik is also near the Svartsengi geothermal plant, the main supplier of electricity and water to 30,000 residents on the Reykjanes peninsula.
Iceland has 33 active volcanic systems, the highest number in Europe.
The Icelandic Met Office had initially said that an eruption would most likely take place “in several days rather than hours”, as magma had been observed accumulating under the Earth’s surface at a depth of about five kilometers for several days.
But late Friday it noted that seismic activity was moving closer to the surface and magma was beginning to rise vertically toward the Earth’s crust between Sundhnjukagigar and Grindavik — suggesting an eruption could come sooner.
Authorities decided to evacuate Grindavik after the Met Office said there was a “likelihood that a magma intrusion has extended beneath Grindavik.”
“At this stage, it is not possible to determine exactly whether and where magma might reach the surface,” it said.
However, it noted that “the amount of magma involved is significantly more than what was observed in the largest magma intrusions associated with the eruptions at Fagradalsfjall”.
Three eruptions have taken place near Fagradalsfjall on the Reykjanes peninsula, in March 2021, August 2022, and July 2023 — all far from any infrastructure or populated areas.
The Met Office said that 500 earthquakes had been registered in the area between 1800 GMT Friday and 0600 GMT Saturday, including 14 over a magnitude of 4.0.
Iceland straddles the Mid-Atlantic Ridge, a crack in the ocean floor separating the Eurasian and North American tectonic plates.