Iceland's Reykjanes Peninsula may soon experience a volcanic eruption.
More than 18,000 earthquakes have shaken the southwestern region over the past week, according to the Icelandic Meteorological Office.
The largest was a 5.7-magnitude tremor on Feb. 24 around 10 a.m. local time. Another magnitude 5 quake hit just 30 minutes later, the agency said.
The earthquakes have caused little damage so far, but they continue to unnerve residents in Reykjavik and other nearby cities, according to CNN.
"I have experienced earthquakes before, but never so many in a row," Reykjavik resident Auður Alfa Ólafsdóttir told CNN. "It is very unusual to feel the Earth shake 24 hours a day for a whole week. It makes you feel very small and powerless against nature."
Þorvaldur Þórðarson, a professor of volcanology at the University of Iceland, told the outlet it is understandable that residents are concerned about the recent uptick in seismic activity.
"Of course it worries people," he said. "For this region, this is actually fairly unusual, not because of the type of earthquakes or their intensity, but for their duration. It's been going for more than a week now."
He continued, "We are battling with the 'why' at the moment. Why is this happening? It is very likely that we have an intrusion of magma into the [Earth's] crust there. It has definitely moved closer to the surface, but we are trying to figure out if it's moving even closer to it."
HALLDOR KOLBEINS/AFP via Getty
Iceland sits along the mid-Atlantic Ridge, which is a set of tectonic plates that are continuously spreading apart from each other, according to the United States Geological Survey.
Most of the ridge is deep underwater and much of its seismic activity cannot be felt by humans, but earthquakes as strong as at least 6.9-magnitude have been felt in Iceland in the past.
Never miss a story — sign up for PEOPLE's free weekly newsletter to get the biggest news of the week delivered to your inbox every Friday.
This unusual uptick in large tremors could be enough to trigger an eruption from one of multiple nearby volcanoes, Iceland's meteorological agency warned. However, experts said an eruption "should not threaten inhabited areas of the peninsula."
More seismic activity is likely in store, with the possibility of a magnitude 6 or 6.5 earthquake in some areas.