Santorini and Kolumbo Magma Link Raises Concerns for east Mediterranean Eruptions

Santorini and Kolumbo Magma Link Raises Concerns for east Mediterranean Eruptions
by Clarence Oxford
Los Angeles CA (SPX) Sep 30, 2025

Santorini's volcanic system, long known for the catastrophic Minoan eruption around 1600 BCE, may be more dangerous than previously understood. A new study in Nature shows that the island's volcano is hydraulically linked with the nearby submarine Kolumbo volcano, creating a coupled magma system that could trigger cascading volcanic crises across the eastern Mediterranean.

The findings come from analysis of the 2024-2025 volcanic unrest, when earthquake swarms and ground deformation forced Greek authorities to declare an emergency. Using land and seafloor seismometers, satellite radar, and ocean-bottom pressure sensors, scientists tracked magma migration in real time. They discovered that a mid-crustal reservoir beneath Kolumbo deflated as magma intruded laterally into a 13-kilometer-long dike extending toward Santorini, while Santorini's shallow reservoir inflated.

In total, about 0.31 cubic kilometers of magma moved, a volume similar to that which has fueled past Kolumbo volcanic chain eruptions. Though no eruption followed, the crisis revealed that Santorini and Kolumbo draw from interconnected reservoirs at depth. This connection means that unrest at one volcano can influence the other, a factor absent from previous hazard models.

Santorini has erupted explosively multiple times, most infamously during the Minoan eruption that devastated Bronze Age Aegean civilizations. Kolumbo erupted in 1650 CE, generating a tsunami and lethal gas release that killed hundreds. The recognition that the two volcanoes can act in concert increases the regional hazard profile.

Researchers highlight several risk factors: magma is actively recharging beneath Santorini, tectonic faults in the Santorini-Amorgos zone create conduits for magma ascent, and shallow-water eruptions near Kolumbo could drive phreatomagmatic explosions and tsunamis. Combined with dense local populations and heavy tourism, even a moderate eruption could have severe consequences.

The study emphasizes the need for integrated monitoring of both volcanoes and contingency planning for coupled crises. While another Minoan-scale eruption is unlikely in the near term, the conditions for explosive activity remain present and interconnected beneath the Aegean.

Research Report:Volcanic crisis reveals coupled magma system at Santorini and Kolumbo