TY - GEN A1 - Günther, S. T1 - The impact of thermophilic sulphate-reducing bacteria on serpentinization reactions N2 - Serpentinization is an important process in the Earth’s oceanic lithosphere, where the reaction of olivine und pyroxene with water forms serpentine and magnetite. During this alteration reaction gaseous hydrogen is produced abiotically, which has been inferred as an essential energy source for microbes living in these systems. The serpentinization reaction directly influences the chemical composition of the lithosphere and the ocean chemistry and, thus, connects the lithosphere, hydrosphere and biosphere. While the geochemical processes are rather well studied in these systems, the biological influence on the processes is not well understood. However, microbial activity has been documented for serpentinization systems, e.g. along the Mid-Atlantic Ridge, in surficial carbonate formations constraining the activity of sulfate-reducing bacteria and methanogenic archaea. The question arises whether microbial populations can be sustained by the hydrothermal alteration of the oceanic lithosphere and whether the microbial populations directly influence and accelerate the serpentinization process. For our experimental setup the surface of mono-mineral cubes of olivine and pyroxene are directly exposed to sulfate-reducing bacteria, using an anaerobic semi-continuous fermenter system. Besides mesophilic sulfate-reducing Bacteria of the Desulfovibrio genus also thermophilic sulfate-reducing enrichment cultures from geothermal, saline fluid systems were included to investigate the mineral surface alteration. The mineral alteration was monitored using electron microprobe analysis, scanning electron microscopy and isotope fractionation of sulfide, while biofilm formation was documented and sulfate reduction activity measured. T2 - VAAM Jahrestagung CY - Würzburg, Germany DA - 05.03.2017 KW - Sulfat-reduzierende Bakterien KW - Sulfate-reducing bacteria PY - 2017 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/39418 AN - OPUS4-39418 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany