Despite their potential impacts, the processes are still not understood, even though significant conceptual progress has been made over the last fifteen years based on the combination of land-based seismological and geodetic data. Because the active processes occur below the ocean floor, further progress is hampered by the lack of appropriate seafloor seismological and geodetic instrumentation.
To address the observational gap in the ocean, the international community must be ready to collect new data at tectonically active zones with the appropriate offshore instrumentation, at as many sites as possible, including in Europe and in its oversea regions, where the existence of multiple active margins requires a multi-facetted, flexible and mobile approach.
Our ambition is to start developing such a pool for France, with the idea of extending this initiative at the European level.
This seaward extension of Résif-epos on-land networks and sensors will allow to get closer to the sources of submarine earthquakes which release most of the seismic energy affecting the Earth. We also anticipate that developing seafloor geodesy will foster our understanding of geodynamic processes, as the development of GPS for continental areas did in the nineties.