Simon Besançon is a CNRS engineer in instrumentation and electronics. Attached to the IPGP, he is integrated in the OBS (Ocean Bottom Seismometer) park of the INSU. Simon is responsible for the maintenance of the instruments, participates in the development and design of new or improved instruments and carries out the operational implementation of the instruments. For Arc en Sub, he is in charge of the deployment of 5 of the 7 so-called broadband OBS or BBOBS, the most powerful and voluminous of the fleet. Over the past 7 years, he has spent almost a year at sea on 15 missions on ships of 5 different nationalities, and has carried out more than 100 OBS deployments, mainly in the Atlantic and Indian Oceans, as well as in the Mediterranean Sea.
Rémi Coltat is currently a post-doctoral researcher at ENS Paris, where he studies the reactions between deep ocean lithosphere rocks and hydrothermal fluids at the axis of ridges using a petrographic and geochemical approach. He first studied these rock-fluid interaction processes in alpine ophiolites during his PhD and now has the opportunity to bring his expertise to the study of present-day ocean systems, by characterising the high and low temperature hydrothermal circulations that occur at the Rainbow hydrothermal site where the Arc en Sub expedition is taking place.