Santorini earthquake swarm triggers evacuations amid fears of larger quake

An earthquake swarm near the popular tourist destination of Santorini and surrounding Greek islands has prompted the deployment of emergency crews, school closures, and voluntary evacuations amid fears of a larger earthquake, according to local media.

Hundreds of earthquakes have been recorded in Greece’s Cyclades island group in the Aegean Sea, according to seismologists. While most have been minor, some have reached magnitudes in the lower 5s and upper 4s.

The swarm has intensified over the past week, with the highest seismic activity detected in the last three days, according to data from the Department of Geophysics-Geothermics at the University of Athens.

The strongest earthquakes in the swarm were recorded on Monday, according to the United States Geological Survey (USGS). A magnitude 5.0 earthquake, the largest at the time, struck at 11:29 a.m., local time, causing shaking in nearby islands, including Santorini. Nearly three hours later, a magnitude 5.1 earthquake followed.

Since Sunday, 12 additional earthquakes above magnitude 4.5 have struck the region, triggering rockslides, local media reported.

Greek seismologists, including Gerasimos Papadopoulos, Manolis Skordylis, and Akis Tselentis, have not ruled out the possibility of a stronger earthquake and have urged the public to remain prepared. Authorities are taking precautionary measures in case seismic activity continues to escalate.

Greek officials have implemented several emergency measures, including deploying rescue teams and closing schools until at least February 7. Citizens have been advised to take preventive actions such as securing non-structural elements in buildings, draining swimming pools, and avoiding large gatherings or visits to abandoned buildings and ports in the affected islands.

“We have a very intense geological phenomenon to handle,” said Prime Minister Kyriakos Mitsotakis. “I want to ask our islanders, first and foremost, to remain calm and follow the instructions of Civil Protection.”

Hundreds of people were seen at Santorini’s main port on Monday afternoon boarding ferries to leave the island, according to the Associated Press. Meanwhile, The Guardian reported that both residents and tourists are voluntarily evacuating the Cyclades, prompting Aegean Airlines and ferry services to increase departures.

“The earthquakes are occurring along a fault zone that runs northeast from Santorini,” said German seismologist Jens Skapski. “This fault zone was the origin of a 7.6 magnitude earthquake in 1956 that caused severe damage in the Dodecanese Islands and triggered a tsunami with waves exceeding 20 meters.”

“The risk that this earthquake swarm will lead to a potentially catastrophic earthquake and tsunami is real but not particularly high,” Skapski added. “An exact assessment is not possible. However, due to the significant risk, precautionary measures are urgently required.”