A powerful earthquake struck near Santorini at 3:04 p.m. on Tuesday, registering 5.0 on the Richter scale, according to the revised assessment from the Geodynamic Institute of the National Observatory of Athens. This is the strongest quake recorded in the area so far.
The epicenter was located 21km south-southwest of Amorgos, a Greek island that has experienced hundreds of tremors in recent days, including a 4.7-magnitude quake earlier on Tuesday and a 4.3-magnitude tremor shortly after.
The ongoing seismic activity in the southern Aegean Sea and the Greek islands of Santorini, Amorgos, Ios and Anafi, has raised concerns among locals and experts. More than 5,000 people left the island on Monday and Tuesday on special flights and extra ferry services in response to the escalating tremors.
Seismologist Akis Tselentis, a professor at the National and Kapodistrian University of Athens and Director of the Geodynamic Institute of Greece and the National Tsunami Center (UNESCO), warned that a stronger earthquake could be imminent.
Seismic Activity not De-escalating
“Seismic activity is not de-escalating; on the contrary, it is intensifying,” Tselentis stated, adding that the major fault of Amorgos, responsible for the devastating 1956 earthquake that destoyed Santorini and left 54 people dead, has been reactivated.
Between February 1 and 4 (until 9 a.m.), more than 43 tremors exceeding magnitude 4.0 have been recorded, with Tuesday’s quake being the most powerful so far. Data from the European-Mediterranean Seismological Center (EMSC) indicates that over 770 earthquakes have occurred in the Aegean area since January 27.
Tselentis emphasized that the seismic activity recorded so far exhibits characteristics of a “preseismic sequence (foreshocks)”. This means, he said, that unless the main earthquake occurs soon, temblors of an even greater magnitude are expected.
While Greek experts do not associate this seismic activity with Santorini’s two active volcanoes, they acknowledge a possible indirect impact.
Meanwhile, Santorini, one of the world’s most popular tourist destinations and a key revenue generator for Greece, has been under scrutiny due to overtourism. In recent decades, construction of hotels and accommodation facilities to meet the increasing demand has frequently occurred without proper spatial planning or permits, raising concerns about the island’s infrastructure resilience in the face of seismic events. Tourism stakeholders now fear the quake activity may impact bookings.
In response to the ongoing earthquake activity, an Interdisciplinary Risk and Crisis Management Committee, convened by the National and Kapodistrian University of Athens on Monday, confirmed that the tremors appear to be part of a “preseismic pattern”. Authorities and experts continue to monitor the situation closely.
