Scientists Discover 73 New Underwater Volcanic Calderas Using AI Mapping

A team led by volcanologist Dr. Andrea Verolino from Paris-Saclay University in France has identified 73 previously unknown volcanic calderas beneath the ocean floor. Using artificial intelligence to analyze bathymetric maps of the seafloor, the researchers detected these massive crater-like depressions formed by the collapse of magma chambers under the sea. The calderas vary in depth up to 5,600 meters and can span diameters as wide as 20 kilometers.

Most of Earth's volcanic activity occurs underwater along tectonic plate boundaries where magma interacts with cold ocean water to build underwater mountains and islands. While many submarine eruptions are relatively gentle basaltic flows, calderas can produce explosive eruptions, tsunamis, and atmospheric shock waves, as demonstrated by the 2022 Hunga Tonga-Hunga Ha'apai eruption in the Tonga archipelago. This event caused widespread destruction and atmospheric pressure waves reaching space.

Prior to this study, fewer than 30 underwater calderas had been documented. The team adapted an algorithm originally designed to identify impact craters on Mars to scan seafloor topography, initially flagging over 87,000 potential features. After filtering and manual verification, 78 calderas were confirmed, including 5 previously known and 73 new discoveries. The findings highlight regions near tectonic boundaries and volcanic arcs as likely locations for such calderas.

The researchers emphasized seven newly identified calderas as priority sites for future investigation due to their depth, shape, and location, which may provide insights into submarine volcanic hazards. Although the study did not assess current volcanic activity, recent research suggests some seemingly dormant underwater volcanoes may still harbor magma and could erupt in the future. This work lays a critical foundation for assessing submarine volcanic risks and enhancing global preparedness.