1. Life at cold seeps: a synthesis of biogeochemical and ecological data from Kazan mud volcano, eastern Mediterranean Sea
- Author
-
Werne, J.P., Haese, R.R., Zitter, T.A.C., Aloisi, G, Bouloubassi, I., Heijs, S., Fiala-Medioni, A., Pancost, R.D., Sinninghe Damste, J.S., de Lange, G., Forney, L.J., Gottschal, J.C., Foucher, J.-P., Mascle, J., Woodside, J.M., MEDINAUT and MEDINETH, Party, Sedimentology, Department of Marine Biogeochemistry and Toxicology, Royal Netherlands Institute for Sea Research (NIOZ), Department of Earth Sciences - Geochemistry [Utrecht], Utrecht University [Utrecht], Department of Sedimentology and Marine Geology Faculty of Earth and Life Sciences, Free University of Amsterdam, Laboratoire d'océanographie dynamique et de climatologie (LODYC), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de biogéochimie et chimie marines (LBCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Microbiology, University of Groningen [Groningen]-Center for Ecological and Evolutionary Studies, Laboratoire d'océanographie biologique de Banyuls (LOBB), Observatoire océanologique de Banyuls (OOB), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité de recherche Géosciences Marines (Ifremer) (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Center for Marine Earth Sciences [Amsterdam], Géosciences Marines (GM), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
GAS HYDRATE ,Biogeochemical cycle ,010504 meteorology & atmospheric sciences ,Aardwetenschappen ,MARINE-SEDIMENTS ,Clathrate hydrate ,MID-ATLANTIC RIDGE ,Geochemistry ,FLUID-FLOW ,010502 geochemistry & geophysics ,01 natural sciences ,Methane ,chemistry.chemical_compound ,mud volcano ,biogeochemistry ,Geochemistry and Petrology ,cold seep fauna ,ARCHAEA ,SDG 14 - Life Below Water ,14. Life underwater ,ComputingMilieux_MISCELLANEOUS ,AUTHIGENIC CARBONATES ,0105 earth and related environmental sciences ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,IN-SITU ,microbiology ,Geology ,Authigenic ,anaerobic oxidation of methane ,15. Life on land ,Cold seep ,Petroleum seep ,Oceanography ,chemistry ,13. Climate action ,Anaerobic oxidation of methane ,ALEUTIAN SUBDUCTION ZONE ,ANAEROBIC METHANE OXIDATION ,LIPIDS ,Mud volcano - Abstract
Recent field observations have identified the widespread occurrence of fluid seepage through the eastern Mediterranean Sea floor in association with mud volcanism or along deep faults. Gas hydrates and methane seeps are frequently found in cold seep areas and were anticipated targets of the MEDINAUT/MEDINETH initiatives. The study presented herein has utilized a multi-disciplinary approach incorporating observations and sampling of visually selected sites by the manned submersible Nautile and by ship-based sediment coring and geophysical surveys. The study focuses on the biogeochemical and ecological processes and conditions related to methane seepage, especially the anaerobic oxidation of methane (AOM), associated with ascending fluids on Kazan mud volcano in the eastern Mediterranean. Sampling of adjacent box cores for studies on the microbiology, biomarkers, pore water and solid phase geochemistry allowed us to integrate different biogeochemical data within a spatially highly heterogeneous system. Geophysical results clearly indicate the spatial heterogeneity of mud volcano environments. Results from pore water geochemistry and modeling efforts indicate that the rate of AOM is similar to 6 mol m(-2) year(-1), which is lower than at active seep sites associated with conditions of focused flow, but greater than diffusion-dominated sites. Furthermore, under the non-focused flow conditions at Kazan mud volcano advective flow velocities are of the order of a few centimeters per year and gas hydrate formation is predicted to occur at a sediment depth of about 2 m and below. The methane flux through these sediments supports a large and diverse community of micro- and macrobiota, as demonstrated by carbon isotopic measurements on bulk organic matter, authigenic carbonates, specific biomarker compounds, and macrofaunal tissues. Because the AOM community appears to be able to completely oxidize methane at the rate it is seeping through the sediments, ultimate sinks for methane in this environment are authigenic carbonates and biomass. Significant differences in organic geochemical data between this site and those of other cold seep environments, even within the eastern Mediterranean mud volcanoes, indicate that the microbiological communities carrying out AOM varies depending on specific conditions such as methane flux and salinity. (C) 2004 Elsevier B.V. All rights reserved.
- Published
- 2004
- Full Text
- View/download PDF