The newest phase of the eruption near Grindavík, Iceland resumed on February 8 with lava erupting to the east of the Svartsengi power station southwest of the nation’s capital, Reykjavík. This is close to the site of the first eruption from this sequence in December 2023. Lava fountains up to 80 meters tall were observed on February 8.
As of 15:00 UTC Thursday lava flows covered Grindavíkurvegur, the main highway connecting Grindavík on the south end to a freeway running between Reykjavík and the nation’s main international airport at Keflavík. The flow also damaged a hot water line running from Svartsengi power station that provides steam heat to much of Reykjanes Peninsula.
Wind patterns are likely to send volcanic gasses out to sea over the coming days though there is a risk of Keflavík International Airport being impacted for brief periods through Saturday (assuming the eruption lasts that long).
Rather than representing separate eruptions, this eruptive sequence appears to make up one eruption from Svartsengi volcano. Scientists at the Icelandic Meteorological Office first noted increased earthquake activity associated with rising magma in the region in October 2023.
In November, officials began constructing levees around critical infrastructure such as Svartsengi power station, a greenhouse facility, and the community of Grindavík (the latter of which also being evacuated). The first eruption began December 18 with the second phase starting on January 14 and the current one on February 8.
Three homes in Grindavík were destroyed during the January lava flows which originated just outside the small town. The other two phases originated about 5 kilometers to the north.
Svartsengi power station is a geothermal plant capable of producing 74 MW of power which is about 2% of the nation’s energy production. It is also home to the Blue Lagoon, a popular tourist site with geothermally heated ponds that are runoff from the power station. The Blue Lagoon has been closed off and on during this eruption and is now cut off from the road network by lava flows.
Sundhnúkur volcano is one of several on the Reykjanes peninsula in Iceland’s southwestern corner. These volcanoes are associated with a portion of the mid-Atlantic Ridge rising above sea level. This ridge is a spreading center running the length of the Atlantic Ocean. In this region it forms the boundary between the North American and Eurasian tectonic plates.
Another volcano just to the east, Fagradalsfjall, has also erupted recently with lava flows being produced periodically between 2019 and 2023. Geological evidence shows that the Reykjanes peninsula experiences phases of eruptions with long-lived dormancy in between. Geologists have been speculating that this may represent the onset of a new period of activity. The most recent ended about 800 years ago and was observed shortly after Vikings settled in Iceland.
Rather than the huge picturesque stratovolcanoes that are icons of the Cascades, these volcanoes are shield volcanoes with fairly gentle slopes formed by overlapping lava flows. Some small mountains are present, largely representing locations where lava flowed out of the earth.
Hawaii presents the most famous examples of shield volcanoes in the United States but the Cascades have produced a few as well. Newberry volcano near Bend, the Boring Lava Field underlying the Portland metropolitan area, and Indian Heaven between Mount Adams and Mount St. Helens are all considered to be shield volcanoes or groupings of shield volcanoes. There is currently no indication of an imminent eruption in the Cascades.
The featured image is of lava fountains photographed on February 8 by the Icelandic Coast Guard.
