Santorini Declares State of Emergency Amid Ongoing Earthquake Swarm
The Greek island of Santorini has been placed under a state of emergency following a series of persistent tremors, including its strongest earthquake in decades. Since late January 2025, the island has experienced thousands of earthquakes, with the most powerful—a magnitude 5.2 quake—striking on Wednesday evening. This was followed by two additional tremors exceeding magnitude 4.0 on Thursday. The seismic activity has raised concerns, though no injuries or significant damage have been reported so far. Santorini’s last major earthquake, a devastating magnitude 7.5 event in 1956, claimed at least 53 lives.
What’s Happening in Santorini?
Santorini, part of Greece’s Cyclades islands in the Aegean Sea, has been rattled by near-constant tremors since January 27, 2025. The recent magnitude 5.2 quake is the strongest recorded since the swarm began. Earthquakes are measured on the Richter scale, with magnitudes above 6.0 considered severe and those around 5.2 classified as moderate.
The island lies along the seismically active Hellenic Volcanic Arc, which stretches from the Peloponnese through the Cyclades. The region is also home to two volcanoes: Nea Kameni, a small islet within Santorini’s caldera, and Kolumbo, an underwater volcano located about eight kilometers northeast of the island.
Where Are the Epicenters?
The earthquakes’ epicenters are clustered between Santorini and nearby islands such as Anafi, Amorgos, and Ios. Most of the seismic activity is concentrated beneath the seabed, which scientists say is preferable to land-based quakes, as the latter tend to cause more destruction. Greece is no stranger to earthquakes, given its location in one of the world’s most seismically active regions.
What Are the Main Concerns?
Authorities are preparing for the possibility of a larger quake, as the tremors show no signs of subsiding. On Wednesday, officials warned of potential landslide risks in certain areas. Vassilis K. Karastathis, a seismologist and research director at the National Observatory of Athens, stated that there is no evidence yet of the seismic activity slowing down. “We are still in the middle of the road,” he said.
While no injuries or major damage have been reported, more than 11,000 people have left the island due to the tremors. Santorini, a popular tourist destination, has a permanent population of around 15,000, according to the 2021 census.
Could the Earthquakes Trigger a Volcanic Eruption?
Despite Santorini’s proximity to two volcanoes, experts believe a volcanic eruption is unlikely. The current earthquakes are not linked to volcanic activity and do not pose a specific volcanic threat. Last week, Greece’s Ministry of Climate Crisis and Civil Protection detected mild seismic-volcanic activity within Santorini’s caldera, but similar activity in 2011 lasted 14 months without leading to any volcanic issues.
Athanassios Ganas, research director at the National Observatory of Athens, noted that while a second pulse of magma could potentially reactivate the situation, there is currently no immediate volcanic hazard. Santorini has a long history of volcanic activity, including a massive eruption around 1,600 BC that shaped the island’s current geological form.
Will the Tremors Continue or Worsen?
Scientists cannot rule out the possibility of a stronger earthquake, potentially up to magnitude 6.0, occurring on nearby faults. Ganas explained that the ongoing seismic activity is transferring stress to neighboring faults, which could trigger a larger quake. However, he emphasized that the most likely scenario is a continuation of the current seismic swarm—a series of small to moderate earthquakes without a single dominant mainshock.
How Are Greek Authorities Responding?
Greek Prime Minister Kyriakos Mitsotakis is scheduled to visit Santorini on Friday to assess the situation. Local authorities have closed schools in Santorini and Amorgos until Friday, deployed rescue teams, and advised residents to avoid ports and indoor gatherings. The state of emergency, declared to address the population’s needs and the seismic activity’s impact, will remain in effect until March 3.
As the island braces for potential further tremors, residents and officials remain vigilant, hoping for a swift resolution to the ongoing seismic crisis.
