Iceland is bracing for a volcanic eruption, as have shaken the southern part of the Reykjanes peninsula since October. The earthquakes were caused by a huge amount of magma from deep inside Earth moving upwards and forming a 15-kilometre-long crack between 2 and 5 kilometres underground. As of 12:30pm GMT on 15 November, no volcanic eruption had begun.
When will the volcanic eruption occur?
No one knows. It is thought likely that an eruption will occur, but it isn鈥檛 certain. The mass of magma could remain where it is and gradually cool rather than erupting.
But I saw videos of an eruption on social media?
These are videos of past volcanic eruptions, such as of the Fagradalsfjall volcano that erupted in 2021, 2022 and July 2023. The Fagradalsfjall volcano is near the new magma intrusion but
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Why is the ground cracking?
The magma intrusion has pushed the land on either side outwards and up, causing the ground immediately above the intrusion to . This has resulted in cracks in the ground, causing a lot of damage in the coastal town of Grindav铆k, whose north-western edge is
What鈥檚 at risk in the region?
The magma intrusion runs from just off the coast, passes under Grindav铆k and continues inland to within a couple of kilometres of a geothermal power plant called Svartsengi. The hot water from Svartsengi is the source for the Blue Lagoon spa nearby, one of Iceland鈥檚 biggest tourist attractions.
What鈥檚 happening there now?
The 3000 residents of Grindav铆k have been evacuated, but they were allowed back briefly to collect belongings, pets and livestock. The Blue Lagoon .
What would happen if there is an eruption?
No one can be sure. It is likely that a fissure vent could form, with a fountain of lava generating a lava flow. 鈥淚t kind of unzips, letting out magma in a long fissure,鈥� says at the University of Leeds, UK, who is in Iceland monitoring the site. 鈥淲e don鈥檛 see necessarily a large, pyramid-shaped stratovolcano.鈥�
How much destruction this causes depends on where it happens and how much lava comes out. If rising lava meets large amounts of groundwater, or the eruption occurs under the sea, there could be an explosive eruption due to the formation of steam. 鈥淚f we are lucky, we will get mostly eruptions within uninhabited valleys like we had in 2021 and 2022 and earlier this year,鈥� says Ilyinskaya.
Can anything be done to protect the town?
In the past, Iceland has sometimes and protect key infrastructure, including on the Reykjanes peninsula. However, the magma chamber stretches for 15 kilometres in this case, and it isn鈥檛 clear where or if lava will start to flow.
During a 1973 eruption that threatened to block a harbour, seawater was sprayed on a lava flow to slow it down, says Ilyinskaya. 鈥淎ctually that was really successful.鈥�
Will an eruption disrupt transatlantic flights?
The basalt eruptions that occur on the Reykjanes peninsula seldom produce much ash, so it is unlikely we will see an impact like that of the Eyjafjallaj枚kull eruption in 2010. 鈥淭his could cause some short-lived disruption to local air traffic,鈥� says Ilyinskaya. 鈥淏ut it is pretty certain there鈥檚 not going to be a lot of disruption to air traffic across the world like in 2010.鈥�
Why have there been so many eruptions in this area recently?
In this part of Iceland, the volcanoes all seem to erupt around the same time every thousand years or so, in cycles called Reykjanes Fires, says Ilyinskaya. The last time this happened was around 800 years ago. 鈥淣ow it鈥檚 pretty clear we are in this very active cycle again. We could be going into these kind of eruptions for the rest of our lifetimes,鈥� she says. 鈥淟uckily, the eruptions that do happen in these [Reykjanes] Fires are all quite small.鈥�
