Geosphere- biosphere studies at the Logatchev hydrothermal vent field, Mid-Atlantic Ridge at 15°N HYDROMAR VII – Cruise No. MSM10/3 - January 11 – February 13, 2009 - Las Palmas (Spain) – Fort de France (France) (English)

R/V MARIA S. MERIAN cruise MSM 10/3 was the last in a series of cruises to the Logatchev hydrothermal vent field at 15°N on the Mid-Atlantic Ridge (MAR) as part of the German Research Foundation’s Priority Program SPP 1144 "From the Mantle to the Ocean". The goal of SPP 1144 was to better understand the geology, chemistry, and biology of hydrothermal vents on the slow-spreading MAR. This cruise had three main goals: 1) to continue and conclude time series studies on the spatial and temporal variability of vent fluids and their effect on vent biota, 2) to better understand how plumes that rise from the Logatchev vents are dispersed in the water column, and how currents and tides influence this dispersal, and 3) to determine the fine structure of the Logatchev hydrothermal vent field and adjoining areas using high-resolution bathymetric mapping. Participating institutions were the Max Planck Institute for Marine Microbiology, the IFM-Geomar, the University of Kiel, the University of Hamburg, the Jacob’s University Bremen, and the French CNRS (Biological Station of Roscoff). The main working tools were the ROV (Remotely Operated Vehicle) Kiel 6000 for Goal 1, a CTD-rosette, Miniature Autonomous Plume Recorders (MAPRs), and oceanographic moorings for Goal 2, and the ship’s Kongsberg EM120 multibeam echosounder for Goal 3. Although weather conditions allowed only five ROV dives in the Logatchev working area, we were able to address most of our goals and recovered all scientific instruments that had been deployed during earlier cruises.