IODP Proceedings Volume contents Search | ||
![]() |
||
Expedition reports Research results Supplementary material Drilling maps Expedition bibliography | ||
|
doi:10.2204/iodp.proc.311.209.2008 IntroductionMicrobial sulfate reduction is the major pathway of organic matter oxidation in coastal marine and continental shelf sediments (Jørgensen, 1982) and is a fundamental process linking the geochemical cycles of carbon, sulfur, and oxygen (e.g., Schidlowski et al., 1983; Berner, 1982; Garrels and Lerman, 1984; Wortmann and Chernyavsky, 2007). Sulfate-reducing microorganisms reduce SO42– according to the following net reaction:
SO42– + 2CH2O
Microbially mediated sulfate reduction affects the isotopic composition of dissolved and solid sulfur species in marine sediments. Although several details of the fractionation process remain controversial, the overall process is well understood and can be described as the sum of several mass-dependent fractionations during the stepwise reduction of sulfate to sulfide and the ratio between the forward and backward reactions (Rees, 1973; Bruechert, 2004; Brunner and Bernasconi, 2005). Experiments and field data show that the
This data report offers |