Iceland volcanic region waking up?

Volcanic activity seems escalating in a region of Iceland that has not erupted for 800 years, with scientists warning it could cause disruption for centuries to come.

Since 21 January, 2020, the Reykjanes peninsula south-west of Iceland’s capital, Reykjavik, has experienced more than 8,000 smaller earthquakes and about 10 centimeters of land uplift due to magma intrusions underground.

Situated close to the town of Grindavík and only 15 kilometers from Iceland’s international airport, the region last erupted about 800 years ago (though there have been more recent eruptions offshore). Geological evidence shows the area is fed by five volcanic systems, which seem to come to life in a coordinated way roughly every 1,000 years.

The last period of volcanic activity on the peninsula lasted from the 10th century until the 13th. Unlike typical Icelandic volcanoes, which tend to wake for a few years and then die down, this region appears to splutter on and off for up to 300 years, producing eruptive episodes (locally known as 'fires') lasting a few decades. Long thin cracks (or fissures) extend up to 8 kilometers, producing fountains of lava, usually without large amounts of ash or explosive activity.

The most recent 'fires' occurred between 1210 and 1240 and covered about 50 sq km of land in lava. At least six separate eruptions occurred, each lasting weeks to months, interspersed with gaps of up to 12 years with no activity. Volcanic rock fragments and particles were carried tens of kilometres by the wind and written sources report the rockfall causing problems for livestock in the area.

Icelanders are used to volcanic activity, but they will be keeping a close eye on the Reykjanes peninsula. Because the eruptions are likely to be relatively small and occasional they will be easier to cope with than massive and sudden outpourings of lava like the 1783-84 Laki eruption, but if the pattern is indeed about to repeat, it will present a new kind of challenge for Icelanders.