BGU's Dr. Orit Sivan and her colleagues from Caltech and the University of Cambridge have shed new light on the mechanism that prevents the release of large quantities of the greenhouse gas methane from the sea floor in to the atmosphere.
Sivan and her colleagues have just published their findings in the prestigious Proceedings of the National Academy of Sciences (PNAS). Methane is an important natural gas, but also a highly effective greenhouse gas, whose major natural reservoir is marine sediments. Fortunately, anaerobic oxidation of methane coupled with sulfate reduction has been shown to consume about 90% of the upwarded methane within the subsea floor environment, preventing its release to the atmosphere.
However, the mechanism of this process has remained enigmatic. In this study, Sivan, of the Department of Geological and Environmental Sciences, and her colleagues provide geochemical evidence for the stimulation of this process by iron oxides in methane seep sediments, and propose a mechanism for the iron involvement. The evidence is based on incubation experiments with seep sediments and measurement of chemical composition and sulfur, oxygen, and carbon isotopes.
Sivan collaborated with Victoria Orphan and Jeffrey Marlow from Caltech and Gilad Antler and Sasha Turchyn from the University of Cambridge.
