The acquisition of bathymetric data on this transit is the initiative of a group of geologists and geophysicists, in consultation with the French Oceanographic Fleet. The overall objective of this initiative is to generalize the acquisition of multibeam echosounder data along transits of the French research vessels, in order to a) fill gaps of the existing medium resolution bathymetric coverage and contribute to the global bathymetric mapping of the oceans, b) establish a protocol for the acquisition, processing and valorization of the data, and c) facilitate research work through the public sharing of the data acquired during these transits. The data are intended for use in medium resolution mapping (digital terrain model with a grid spacing of about 100 meters). The data acquisition during transit can be constrained : - the speed of the vessel is the one set by the transit, without adjustment with respect to the quality of the data or their resolution. - the multibeam echosounder is placed in an automatic mode. The real-time acquisition is not necessarily followed continuously by a specialized operator. - the sound velocity profiles used for data acquisition are established from global tables of temperature and salinity, without in-situ measurements during acquisition (temperature probes). The data are pre-processed and validated and are intended to be made available in the short term through the Ifremer Sismer research vessel database. The acquisition is limited to international waters, for which no authorization request is necessary. This initiative is also in interaction with the Seabed2030 project (seabed2030.org).