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The main research goals for the MenezMar cruise were achieved thanks to the excellent team work with the RV Meteor crew and Captain, the ROV Quest Team, the scientific crew, the good weather conditions, and the Portuguese authorities that
allowed us to work in their waters. A total of 23 ROV dives were used for video mosaicking of hydrothermal vent habitats, detailed measurements of physico chemical environmental parameters with various state of the art in situ instruments,
coordinated sampling of hot and diffuse hydrothermal vent fluids, macro- and
microbiota and geological samples, performance of various biological in situ experiments, and the recovery of experiments deployed during a preceding R/V POSEIDON cruise in August 2010. A further milestone of the cruise was the
discovery of a new hydrothermal vent site about 5 kilometers away from the known vent field Menez Gwen by gas bubble flare detection with R/V METEOR’s new EM 122 multibeam echo sounder in combination with the analyses of water column sample and sensor data. Only a single ROV dive with QUEST was needed to locate the site on the seafloor, and hot smokers and animals typically found at vents on the Mid-Atlantic Ridge were discovered. Gas bubble analyses revealed at least five other vent plumes in the vicinity, indicating that many more of these small active sites exist along the Mid-Atlantic Ridge than previously assumed