Iceland is experiencing an eruption “which could be the largest known since 2021”, estimates a volcanologist

A volcanic eruption began on Monday in the southwest of the country, near the capital, Reykjavik.

The current eruption in Iceland “is not of a tourist nature”because “this could be the biggest known on the island since 2021”, analyzes Patrick Allard, volcanologist at the Institute of Globe Physics in Paris this Tuesday on franceinfo. Iceland has been in the grip of a new volcanic eruption since Monday evening near the village of Grindavik, south of the capital Reykjavik. The images show a wall of fire almost three kilometers long.

franceinfo: What does this wall of fire correspond to?

Patrick Allard: It is the gushing of magma through the fractures which opened during the night from Monday to Tuesday, which are almost four kilometers long. This magma, which had been building since November 10, had accumulated without making too much noise in recent weeks. We even believed that perhaps the eruption would not take place, although it was believed to be imminent at the beginning of November. It finally happened with few warning signs Monday evening.

“We have this wall of fire, what we call lava fountains, that is to say magma that gushes out and spreads on each side of the fracture.”

Patrick Allard, volcanologist

at franceinfo

Can this fault get bigger? Is it dangerous?

So that’s the problem. For the moment, the zone of magma intrusion, that is to say the establishment of magma since the beginning of November, is fifteen kilometers long. The head of the intrusion was further north. This is where the eruption started last night. The problem is that the fractures spread south overnight and now the southernmost head of the fractures is three kilometers from the port town of Grindavik, a town already evacuated in November and very close especially of the Svarstengi geothermal power plant, which is important for both heating and electricity generation for Grindavik and Reykjavik.

Do you know what it can feel like to be there? Does it smell anything for example?

Any eruption emits a lot of magmatic gases: water vapor, CO2, but also a lot of sulfur dioxide, hydrochloric acid, hydrofluoric acid… These are toxic gases. It sure smells. This is not a tourist rash. The first three eruptions since 2021, we could get quite close. It wasn’t very violent. There, it’s on a larger scale.

Is this a sign of a resumption of volcanic activity in Iceland that could last?

It’s an active area. This is the zone where the American and Eurasian plates separate. This area had been inactive for 800 years. We have entered a new cycle of eruptive and seismic activity in this area in 2021 with already three eruptions. This could be the biggest since the start of this streak.

And do we have an idea of ​​how long this eruption could last?

No, we have no idea, but it is generally proportional to the quantity of magma accumulated in the subsoil, barely three to five kilometers deep. It is also proportional to the available energy that this magma has, that is to say the quantity of gas it contains. Finally, it is also proportional to the opening of the fractures. The 2021 eruption lasted two months. This could last longer.