Things had recently become quiet on the Icelandic Reykjanes peninsula. But on Monday evening around 10 p.m. the earth cracked and since then a new volcano has been spewing lava over a length of about four kilometers. The special thing about this eruption: There is not a single volcanic cone, but rather a crack along the old Sundhnúka crater series, which was last active in the 13th century and from which the magma at night spewed fountains up to 120 meters highas helicopter footage shows.
From the southern end of the volcanic chain it is about three kilometers to the village of Grindavík. The Svartsengi power plant, which supplies electricity and water to the entire Reykjanes peninsula, is also located just a few kilometers from the fissure. The Icelandic Parliament passed a bill on November 13th allowing the construction of lava barriers around the power plant and the adjacent Blue Lagoon, the famous thermal resort that has been closed since November 9th.
In November there were tremors every minute for a few days, up to 800 quakes a day. An underground fissure had filled with magma over a length of 15 kilometers, and the lava temporarily rose to 500 meters below the earth’s surface. In Grindavík, entire streets were torn open, house walls were destroyed, the place had to be evacuated on November 10th, and the almost 4,000 residents have been living with friends and relatives or in three emergency shelters ever since. Since the magma had sunk to around five kilometers again at the end of November, there was hope that the situation would calm down and residents were allowed to stay in Grindavík again during the day.
Directly beneath Iceland runs the Mid-Atlantic Ridge, a huge fault zone where the North American and Eurasian lithospheric plates are drifting apart. The entire island in the North Atlantic is, so to speak, a product of this plate movement; there are 30 volcanic systems here. The Reykjanes peninsula, in turn, lies directly on the actual fracture zone and therefore also on the main line of volcanoes.
100 to 200 cubic meters of magma escape every second
The Icelandic volcanologists had expected an eruption similar to that of Fagradalsfjall, a small volcano also located on Reykjanes, which has been active three times in recent years and has each flowed out its lava rather peacefully. Now around 100 to 200 cubic meters of magma are emerging every second, which is at least ten times the amount of lava that the Fagradalsfjall produced during its 2021 eruption.
The Icelandic Civil Defense declared an emergency level in the affected region. Police asked onlookers not to approach the volcano. The orange lava glow from the eruptions was clearly visible throughout the night from the capital Reykjavík, 40 kilometers away.
So far, the lava is not flowing towards Grindavík, but in the opposite direction to the east and north. It would be dangerous for the town and the power plant if the gap were to open further to the south, but it doesn’t look like that at the moment.
Volcanologist Thorvaldur Thórðarson estimates that initially between 30,000 and 60,000 tons of sulfur dioxide will be released into the atmosphere every day. However, his colleague, the geophysicist Páll Einarsson, predicted that the eruption would weaken across the board in a few days and that the activity would shrink to individual craters or even just a single crater.