Similar tremors have been observed before volcanic eruptions in the past, and the Icelandic Meteorological Office said that the movements of magma were a likely cause for continued activity. The agency warned that an outbreak could occur within days or weeks.
“The two tectonic plates are moving away from each other and this movement created the conditions for the magma to surface,” said Freysteinn Sigmundsson, a professor of geophysics at the University of Iceland.
Dr. Einarsson said that of the five volcanoes in the Reykjanes area, the movement of magma has been observed close to at least three of them since the seismic episode started in December 2019. “We may be entering a new active period on the peninsula,” he added . “There seems to be food for an eruption.”
Iceland has about 30 active volcanoes, but volcanologists say an eruption in Reykjanes will not threaten the inhabited areas of the peninsula. “We are talking about an effusive, rather than explosive, eruption,” said Dr. Sigmundsson, explaining that the lava would likely bubble with little explosive force.
He added that any activity is unlikely to be as disturbing as the eruption that occurred in 2010, when another volcano in Iceland launched an ash cloud so vast that it caused one of the most significant air traffic disruptions in decades, trapping millions of passengers in Europe, some for weeks.
The meteorological office said the volcanic activity could occur near Fagradalsfjall, 20 miles south of Reykjavik, or near the nearby Keilir mountain. Hundreds of volcano enthusiasts have been hooked up to live cameras in the area and to a website that asks “Has there ever been an eruption?” kept them up to date. (It still said “Nei” – No – on Thursday afternoon, but a playlist on the website helped with the wait.)
The meteorological office said that among the possible scenarios, the ongoing seismic activities could decrease in the coming days or weeks, but the peninsula could also face more earthquakes, of magnitude 6.5.