This work presents a new high-resolution multibeam bathymetric map of a segment of active deep sea-floor spreading in the Atlantic Ocean, the northern Mid-Atlantic Ridge (MAR) at 45–46º N. New high-resolution bathymetry data were acquired using an Atlas multibeam echosounder onboard the research vessel Sarmiento de Gamboa during the EXPLOSEA-2 survey in 2019. The final map of the MAR (50 m cell grid size) at the original scale of 1:200,000 shows a segment of 140 × 35 km of the MAR, at water depths from 715 to 3700 m. This new high-resolution bathymetric map allows to better defining the submarine morphology of the Moytirra hydrothermal active field, the only high-temperature field identified between the Azores Archipelago (Portugal) and Iceland. ROV submarine observations reaching the deepest part of the system for the first time show giant anhydrite-sulfide chimneys up to 20 m high, active strong black smokers and polymetallic massive sulfides.
Funding
The EXPLOSEA-2 cruise was funded by the Ministerio de Ciencia e Innovación of Spain as part of the project EXPLOSEA (CTM201675947-R, http://www.igme.es/explosea). The EXPLOSEA2 cruise benefit from the Scientific Agreement between Spain and Portugal to share oceanographic vessels and ROV. This study also benefits from the Atlantic Seabed Mapping International Working Group (ASMIWG) as part of the Atlantic Ocean Research Alliance Coordination and Support Action (AORA-CSA). This study is a contribution to the EMODNET-Geology project funded by the Executive Agency for Small and Medium-sized Enterprise (EASME/EMFF/2018/1.3.1.8-Lot 1/SI2.811048) and the GeoERA-MINDeSEA project funded by the Directorate-General for Maritime Affairs and Fisheries (Grant 731166, project GeoE.171.001). CV is supported by the Fundação para a Ciência e a Tecnologia (FCT) under the PhD fellowship (SFRH/BD/129683/2017) and strategic project (UIDB/05634/2020), PO2020 FunAzores (ACORES 01-0145-FEDER-000123) funded by the Azores Operational Program from European Regional Development Fund (ERDF), and H2020 SponGES project funded by the Horizon 2020 research and innovation program under grant agreement No. 679849.
