Ocean drones enabling long-term earthquake monitoring in target zones

Seismic station coverage in the oceans is limited due to high costs and logistical challenges, leading to insufficient earthquake data from oceanic regions. Ocean drones, with quiet operation, buoyancy-driven mechanics, and autonomous underwater profiling, provide a promising alternative for near-real-time data acquisition. We evaluated an oceanic seismological platform using 6 years (2015-2021) of passive acoustic monitoring data from ocean drones in the Santos Basin, southeastern Brazil, originally not designed for earthquake monitoring. Our analysis identified 12 potential earthquake signals, characterized by low-frequency seismic energy and emergent patterns. These findings demonstrate that ocean gliders are highly effective for earthquake monitoring, offering significant advantages for long-term, targeted seismic observations in coastal and marginal areas where conventional methods often face operational limitations.