Physical oceanography during METEOR cruise M60/3 at the Logatchev hydrothermal field in the mid-Atlantic

The R/V METEOR cruise M60/3 took place from January 13 through February 14, 2004. Target area was the Logatchev hydrothermal field situated on the Mid-Atlantic Ridge (MAR) with main spots around 14°45'N and 44°59'W and 14°55'N and 44°55'W. The active Logatchev hydrothermal field lies on a small plateau on the eastern flank of the inner rift valley in 2900 m to 3060 m water depth. It is characterized by sites of active, high-T fluid emanation and sulfide precipitation as well as by inactive sites. CTD data for 17 stations located in the vicinity of the Logatchev hydrothermal field were recorded using a SEABIRD CTD Type 911, mostly for the entire water column. CTD sensors had been calibrated by SEABIRD directly before the cruise; additional calibrations of the data obtained, e.g. by salinometer measurements of selected samples were not accomplished. For most stations, no indication of hydrothermal plumes could be identified within the CTD-profiles. An exception is station M60/3-37-CTD-R for which the S/T plot evidences the intrusion of a component relatively depleted in salinity for the depth area from 2600m to 2700m water depth.

Stable C and N isotopes and percent C as well as N composition of plankton from the North Atlantic

Elemental C and N percent composition and natural abundance of stable C and N isotopes of plankton species and/or size-fractions collected in several cruises on the N Atlantic Ocean from Greenland to Norway and around Iceland. Determinations included key copepod and krill species. Lipid extraction was performed in some samples to determine carbón isotope depletion factors.

Sediment community responses to marine versus terrigenous organic matter in the Whittard canyon

The Whittard canyon is a branching submarine canyon on the Celtic continental margin, which may act as a conduit for sediment and organic matter (OM) transport from the European continental slope to the abyssal sea floor. In situ stable-isotope labelling experiments (JC36-042-Spre01; JC36-100-Spre01) were conducted in the eastern and western branches of the Whittard canyon testing short term (3 - 7 day) responses of sediment communities to deposition of nitrogen-rich marine and nitrogen-poor terrigenous phytodetritus. Isotopic labels were traced into faunal biomass and bulk sediments, and the bacterial polar lipid fatty acids (PLFAs). These data files provide the data on macrofaunal and bacterial uptake of the isotopically-labelled organic carbon and nitrogen, and macrofaunal community composition at the two stations within the Whittard canyon