Start of a series? Volcanic eruptions in Iceland could last for decades to come

The southwest of Iceland is plagued by numerous volcanic eruptions. Researchers suspect that the recent lava flows are just the beginning of a long-lasting series.

According to researchers, the latest volcanic eruptions on Iceland could last for decades to come. The country's most densely populated region and its vital infrastructure may be threatened for a long time to come, according to a study by international researchers published on Wednesday in the journal "Terra Nova".

The series of eruptions began in 2021 on the Reykjanes Peninsula in the southwest of the island, just 55 kilometers southwest of the capital Reykjavik. There have been five major volcanic eruptions since December last year alone. Lava flowed out of elongated cracks in the earth, which is why this type of eruption is also known as a fissure eruption. Some houses were covered in lava.

Affected region relatively densely populated

A large part of the population of the North Atlantic island lives in the affected region. It is also home to the only international airport and several geothermal power plants that supply the country with hot water and electricity. According to the study, the peninsula was last volcanically inactive almost 800 years ago.

For their study, the researchers analyzed earthquake data from the past three years and took lava samples from several locations. They compared the liquid rock that flowed out of the earth at various locations in terms of its chemical and physical properties. In this way, they wanted to determine whether it came from the same magma chamber underground or from different chambers.

The petrographic properties of the magma

According to the investigations, the magma actually has similar petrographic properties. This suggests a coherent underground magma system, the researchers write. Together with the seismic data, they come to the conclusion that it is a moderately large magma accumulation at a depth of around nine to eleven kilometers, which extends over a width of ten kilometers. It formed between the years 2002 and 2020.

The research team concludes that the current series of eruptions could be the beginning of a long episode. However, they cannot predict how long the series will actually last. "Nature is never regular," said co-author Ilya Bindeman, volcanologist and professor of earth sciences at the University of Oregon in the USA. "We don't know how long or how often it will continue over the next ten or even hundred years. A pattern will emerge, but nature always has exceptions and irregularities."

Iceland is located on the Mid-Atlantic Ridge, the tectonic plate boundary where the North American and Eurasian plates are moving apart. Volcanic eruptions are therefore frequent in Iceland, but the eruptions of the more centrally located volcanoes usually only last a few days or weeks, such as the eruption of the Eyjafjallajökull volcanic glacier in 2010. The fissure eruptions, on the other hand, can last much longer.

dpa