Dynamics of methane and hydrogen sulphide in the water column and sediment of the Namibian shelf Volker Brüchert 1 , Bronwen Currie 2 , Kay-Christian Emeis 3 , Rudolf Endler 4 , Thomas Leipe 4 , Kathleen R. Peard 2 , Thomas Vogt 5 1 Max-Planck Institute for Marine Microbiology and Research Center Ocean Margins, Bremen 2 Ministry of Fisheries and Marine Resources, Namibia 3 Institute of Biogeochemistry and Marine Chemistry, University of Hamburg 4 Institute for Baltic Sea Research, Warnemünde 5 Geoscience Department University of Bremen
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Dynamics of methane and hydrogen sulphide in the water column and sediment of the Namibian shelf Volker Brüchert 1, Bronwen Currie 2, Kay-Christian Emeis.
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Dynamics of methane and hydrogen sulphidein the water column and sediment
of the Namibian shelf
Volker Brüchert 1, Bronwen Currie 2, Kay-Christian Emeis 3, Rudolf Endler 4, Thomas Leipe 4, Kathleen R. Peard 2, Thomas Vogt 5
1 Max-Planck Institute for Marine Microbiology and Research Center Ocean Margins, Bremen2 Ministry of Fisheries and Marine Resources, Namibia3 Institute of Biogeochemistry and Marine Chemistry, University of Hamburg4 Institute for Baltic Sea Research, Warnemünde5 Geoscience Department University of Bremen
Depth range 75 – 95 m (1m – contour lines)Ship direction 180° 14°20‘E, 22°51‘S
< 660m >
Efficient anaerobic oxidation of methane by sulfate in areas where the depth of free gas is greater than than one meter
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Emeis, Brüchert et al. (2004)
Evidence for gas escape from the sediment
Bubbles tracked by echosounder
Meteor M 57-3
Pore water methane, sulphate, and sulphide in sediment crater
181 gravity core
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Rising mud islands and coast-wide fish kills
Lobster kills
Turquoise, elemental sulfur-containing surface water
MODIS satellite imagery:turquoise discolourations often coincide with reportsof hydrogen sulphide smell;measurements indicatesulphur concentrations up to 30 moles/L.
• Brüchert V., Jørgensen B.B., Neumann K., Riechmann D., Schlösser M., and Schulz H. Regulation of bacterial sulfate reduction and hydrogen sulfide fluxes in the central Namibian coastal upwelling zone. Geochimica et Cosmochimica Acta, 2003; 67: 4505-4518.
• Brüchert V., Lass U., Endler R., Dübecke A., Julies E., Leipe T., and Zitzmann S. An integrated assessment of shelf anoxia and water column hydrogen sulphide in the Benguela coastal upwelling system off Namibia, In Past and Present Marine Water Column Anoxia, L.N. Neretin, B.B. Jorgensen, and J.W. Murray, eds.: Kluwer; in press.Emeis K.-C., Brüchert V., Currie B., Endler R., Ferdelman T.G., Kiessling A., Leipe T., Noli-Peard K., Struck U., and Vogt T. Shallow gas in shelf sediments of the Namibian coastal upwelling ecosystem. Continental Shelf Research, 2004; 24: 627-642.
• Weeks S.J., Currie B., Bakun A., and Peard K.R. Hydrogen sulphide eruptions in the Atlantic Ocean off southern Africa: implications of a new view based on SeaWIFS satellite imagery. Deep-Sea Research, 2004; 51: 153-172.