【作者】 常华进； 储雪蕾； 黄晶； 冯连君； 张启锐；

【Author】 CHANG Huajin~(1,2,3)),CHU Xuelei~(1,2)),HUANG Jing~(1,2,3)),FENG Lianjun~(1,2)),ZHANG Qirui~(1)) 1) Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029; 2) Key Lab of Mineral Resources,Chinese Academy of Sciences,Beijing,100029; 3)Graduate University of the Chinese Academy of Sciences,Beijing,100049

【机构】 中国科学院地质与地球物理研究所； 中国科学院矿物资源研究重点实验室； 中国科学院研究生院；

【摘要】 缺氧的沉积环境中存在大量的细菌,它们消耗硫的化合物为其新陈代谢提供能量,并导致硫的化合物被还原、氧化或（和）歧化。细菌的还原作用和歧化作用都能造成明显的硫同位素分馏。细菌硫酸盐还原造成的硫同位素分馏一般在4‰～46‰之间,平均为21‰;细菌参与的氧化作用所造成的硫同位素分馏很小,不到5‰;硫的中间价态物质(S⁰、S₂O₃^2-和SO₃^2-)的歧化作用可以造成7‰～11‰的硫同位素分馏。主要依据实验研究和现代海洋观测获得的细菌还原和歧化作用的硫同位素分馏结果已经被用于解释古代沉积物中的硫同位素记录,成为研究地球历史上古海洋的化学演化的重要手段。更多还原

【Abstract】 Plentiful bacteria are observed in anoxic sediments,where inorganic sulfur compounds can be reduced, oxidized,or/and disproportionately reacted by bacterial action and the bacteria acquire metabolic energy through those reactions.Bacterial reduction and disproportionation bring a significant isotope fractionation.For bacterial sulfate reduction（BSR）,in general,the isotope fractionation between sulfate and H₂S ranges between 4‰and 46‰,with an average of 21‰,but the isotope fractionation is small（less than 5‰） and negligible for bacterial sulfide oxidation.The bacterial disproportionation of the sulfur intermediates,such as S⁰,S₂O₃^2- and SO₃^2-,results in isotope fractionations of 7‰～ll‰.The information of sulfur isotopic fractionation from cultural experiments and modern ocean investigations has been used to interpret sedimentary record and reconstruct chemical evolution of ocean in the Earth history.更多还原