PURGE-AND-TRAP GC-MS ANALYSIS OF VOLATILE ORGANIC-COMPOUNDS FROM THE GUAYMAS BASIN HYDROTHERMAL SITE (GULF OF CALIFORNIA)

During the French-Mexican cruise 'Guaynaut', carried out in November 1 991 in the southern depression of the Guaymas Basin (gulf of Californi a), an actively spreading oceanic basin, various samples were collecte d by means of the submersible 'Nautile'. The on-line coupling of purge and trap to capillary gas chromatography-mass spectrometry (P/T-GC-MS ) has been applied to the analysis of volatile organic compounds (VOC) in water, sediments and hydrothermal deposit samples in order to cont ribute to the characterization of the bacterial microflora activity wh ich is developed on this particular hydrothermal site. The results obt ained for alkanes, monoaromatic hydrocarbons and organosulfur compound s lead to successful interpretation in terms of bacterial activity.