MoMARDREAM-Naut Leg 2 & BBMoMAR cruises

Integrated studies at the Lucky Strike vent fields (MoMAR)

V. Ballu1, W. Crawford2, J. Escartin2, P.-M. Sarradin3 and Science Parties*

The 2nd leg of the MoMARDREAM-Naut cruise (19-28 July 2007) onboard "PourQuoi Pas?" (IFREMER/SHOM) with the submersible Nautile (IFREMER) will carry out multidisciplinary and integrated studies at the Lucky Strike hydrothermal site. Additional field work will be carried out onboard "Suroit" (IFREMER) during BBMoMAR (18-28 July 2007). This 2007 field work is part of a coordinated effort within the French MoMAR program to monitor active processes and their feedback at a slow-spreading segment, and it is funded primarily by CNRS, INSU and IFREMER.

Lucky Strike is the target for integrated and long-term monitoring projects within the MoMAR program. The goal is to understand the feedback between active processes operating at this site, including seismicity and deformation, hydrothermal activity, and the ecosystems that it supports. These cruises encompass several projects, 3 of which are multi-year. The results of these cruises, and the time series recorded by the instrumentation deployed will provide the basis for the full development of an integrated study site at a slow spreading ridge, and for the installation at longer term of a seafloor observatory within the European ESONET program. Installation of instrumentation at the seafloor for long-term measurements was initiated in 2006, during the Graviluck'06 and MOMARETO cruises. These included temperature sensors, time-lapse cameras, pressure gauges, geodetical benchmarks, geomicrobiological incubators, geochemical sensors and biological samplers. During the 2007 cruises instrumentation at the seafloor will be recovered so as to obtain a 2006-2007 time series. Redeployment of instruments, and expansion of the monitoring with additional sensors (i.e., OBSs for microseismicity) will provide time series for 2006-2007 and 2007-2008. These time series will include temperature, pressure, seismicity, electromagnetism, chemistry, ecology, imagery, geomicrobiology, etc.

Information on the MoMARDREAM-Naut Leg 2 cruise can be found at: http://www.insu.cnrs.fr/a2255,debut-de-la-campagne-momardream.html