Massive Undersea Hydrothermal Field Discovered off Greece

Scientists have discovered a surprisingly large hydrothermal vent field near Milos, Greece, revealing Earth's dynamic interior through boiling fluids and vibrant microbial life. The discovery, made public on December 30, 2025, highlights the role of seafloor fault lines in releasing hot, gas-rich fluids, according to MARUM - Center for Marine Environmental Sciences, University of Bremen.

The extensive underwater vent system was found hidden along active fault lines beneath the seafloor near Milos. These geological fractures act as pathways for hot, gas-rich fluids to escape, forming clusters of vents with striking visual diversity, according to researchers.

The discovery surprised researchers, who observed boiling fluids and vibrant microbial mats during deep-sea dives. Sampling of fluids reaching 180 degrees was also conducted. Milos now stands out as one of the Mediterranean's most important sites for studying Earth's dynamic interior, according to the MARUM - Center for Marine Environmental Sciences, University of Bremen.

The findings, detailed in Scientific Reports, emphasize the significance of Milos as a key site for studying underwater geological activity and its potential impact on marine ecosystems. The research team plans to further investigate the site to understand the full extent of the hydrothermal field and its influence on the surrounding environment.