On the potential of underwater DAS

https://www.gotomeet.me/SeminairesGeosciencesENS Résumé : Distributed Acoustic Sensing (DAS) is a recent instrumental development allowing to turn optical fibers into long and dense seismo-acoustic arrays. In 2019, several studies have demonstrated the ability to get meaningful measurements from seafloor telecom cables. Therefore, DAS carries high hopes after decades of efforts to find an efficient and cost-effective solution to monitor geophysical signals on the sea-bottom. In this seminar, I will present some recent works investigating signals recorded from one cable in the South of France, and two cables in the South-West of Greece. For the most part, these cables are laid on the seafloor and not buried. This configuration is probably less ideal but representative of the vast majority of the global network of seafloor telecom cables. I will highlight some limitations of the approach, but also stress that the technology continues to hold promising prospects for tackling long-standing scientific questions and respond to pressing societal needs.