Magma Shift Between Santorini and Kolumbo Volcanoes Fueled 2025 Earthquakes, Scientists Say

A probe vessel astatine Santorini’s Volcano. Credit: Amna

The volcano astatine Santorini, 1 of Greece’s astir iconic islands, is showing caller signs of activity. A survey led by Marius P. Isken, and published successful Nature, has revealed that the Santorini and Kolumbo volcanoes, lone 7 kilometers (4.34 miles) apart, whitethorn stock a heavy underground magma system.

The findings shed airy connected the events of aboriginal 2025, erstwhile a almighty seismic situation shook the region, forcing Greek authorities to state a authorities of emergency.

Signs of unrest emerged months before

Researchers began detecting changes beneath Santorini successful mid-2024. Instruments recorded a gradual uplift of the caldera floor, signaling magma question underground. Gas emissions from the island’s cardinal vents besides rose.

Then, connected January 27, 2025, an earthquake swarm erupted northeast of Santorini. Tremors lasted for much than a month, spreading toward Kolumbo and the surrounding islands.

The University of Athens successful Greece person reported 15,300+ earthquakes connected Santorini successful conscionable the past 15 days, thing that has ne'er happened successful the past of the planet! #Santorini #Amorgos #Greece #Cyclades #Earthquake #Earthquakes pic.twitter.com/gMjSXd1w1C

— LeanneSpurs (@LeanneSpurs) February 16, 2025

The situation was terrible capable that the Greek authorities declared a authorities of exigency successful Santorini and besides closed schools. For an land that draws millions of tourists each year, the exigency measures struck astatine the bosom of Greece’s economy.

By the extremity of February, the crushed astatine Santorini had risen much than 10 centimeters (almost 4 inches), portion Kolumbo’s seafloor had sunk by arsenic overmuch arsenic 32 centimeters (just implicit 1 foot). Such deformation suggested that ample volumes of magma were moving.

Evidence points to a shared magma system

The study combined information from land-based seismic stations, ocean-bottom sensors, GPS measurements, and outer radar. Researchers reconstructed the magma displacement beneath the 2 volcanoes. They recovered that Santorini’s ostentation preceded the intrusion of a monolithic magma-filled dike—an underground sheetlike body—that originated from Kolumbo.

About 0.31 cubic kilometers (74 cardinal gallons) of magma intruded into a 13-kilometer (about 8 miles) agelong fracture, reactivating faults successful the crust earlier halting conscionable a fewer kilometers beneath the seafloor.

The simultaneous ostentation astatine Santorini and deflation astatine Kolumbo suggest the 2 volcanoes whitethorn beryllium hydraulically linked. Magma appears to migrate betwixt their reservoirs, showing they are not autarkic systems arsenic erstwhile thought.

Historic eruptions loom ample successful Greece’s memory

Santorini and Kolumbo beryllium to the aforesaid volcanic tract and some person a grounds of explosive eruptions that shaped Greek history.

The Minoan eruption of Santorini astir 1600 BCE devastated Aegean civilizations and remains 1 of the largest eruptions successful the past 10,000 years. Kolumbo erupted successful 1650 CE, sidesplitting radical connected Santorini and adjacent islands and generating a tsunami that struck the Aegean coast.

The caller survey suggests the 2025 unrest is portion of a agelong rhythm of rejuvenation. It besides confirms earlier hints that the 2 volcanoes tin power each other. Historical accounts adjacent picture simultaneous enactment astatine some sites. For Greece, these findings reenforce the urgent request for semipermanent hazard readying crossed the Aegean.

Outlook for hazards and monitoring successful Greece

Analysis of much than 30,000 events revealed that the dike intrusion expanded successful bursts. Each surge coincided with larger quakes and accelerated aboveground deformation. Between surges, smaller quakes indicated gradual magma pressurization.

The exemplary besides shows that magma flowed from a mid-crustal reservoir beneath Kolumbo into the dike, portion Santorini’s shallow enclosure inflated. This signifier suggests a complex, multi-storage strategy wherever reservoirs interact and sometimes vie for magma supply.

Although nary eruption followed the crisis, scientists pass that the interplay betwixt Santorini and Kolumbo increases the hazard of aboriginal activity.

The dike stopped earlier reaching the surface, but its shallow path—through crust lone a fewer kilometers heavy and successful waters little than 200 meters (656 feet) deep—raises concern. Such conditions could marque immoderate aboriginal eruption much explosive and perchance disruptive for Greece.

Need for monitoring and preparedness successful Greece

The survey highlights the value of high-resolution monitoring. Greek institutions, including the National Observatory of Athens and Aristotle University of Thessaloniki, already play a cardinal relation successful tracking seismic and volcanic activity. However, arsenic the 2025 situation showed, adjacent with wide informing signs, predicting the nonstop people of events remains difficult. Continuous reflection and preparedness are indispensable to safeguard Greece’s people, heritage, and future.