DOI: 10.1111/gbi.12086
Scopus记录号: 2-s2.0-84902377092
论文题名: Barite in hydrothermal environments as a recorder of subseafloor processes: A multiple-isotope study from the Loki's Castle vent field
作者: Eickmann B. ; Thorseth I.H. ; Peters M. ; Strauss H. ; Bröcker M. ; Pedersen R.B.
刊名: Geobiology
ISSN: 1472-4677
EISSN: 1472-4669
出版年: 2014
卷: 12, 期: 4 起始页码: 308
结束页码: 321
语种: 英语
Scopus关键词: barite
; black smoker
; channel
; hydrothermal system
; isotopic composition
; leaching
; mid-ocean ridge
; oxygen
; pyrite
; seawater
; sulfate
; Arctic
; Loki
; barium sulfate
; iron
; pyrite
; sulfide
; sulfur
; Arctic
; chemistry
; Gram negative anaerobic bacteria
; hydrothermal vent
; isolation and purification
; microbiological phenomena and functions
; Arctic Regions
; Barium Sulfate
; Hydrothermal Vents
; Iron
; Microbiological Processes
; Sulfides
; Sulfur Isotopes
; Sulfur-Reducing Bacteria
Scopus学科分类: Earth and Planetary Sciences: General Earth and Planetary Sciences
; Environmental Science: General Environmental Science
; Agricultural and Biological Sciences: Ecology, Evolution, Behavior and Systematic
英文摘要: Barite chimneys are known to form in hydrothermal systems where barium-enriched fluids generated by leaching of the oceanic basement are discharged and react with seawater sulfate. They also form at cold seeps along continental margins, where marine (or pelagic) barite in the sediments is remobilized because of subseafloor microbial sulfate reduction. We test the possibility of using multiple sulfur isotopes (δ34S, Δ33S, {increment}36S) of barite to identify microbial sulfate reduction in a hydrothermal system. In addition to multiple sulfur isotopes, we present oxygen (δ18O) and strontium (87Sr/86Sr) isotopes for one of numerous barite chimneys in a low-temperature (~20 °C) venting area of the Loki's Castle black smoker field at the ultraslow-spreading Arctic Mid-Ocean Ridge (AMOR). The chemistry of the venting fluids in the barite field identifies a contribution of at least 10% of high-temperature black smoker fluid, which is corroborated by 87Sr/86Sr ratios in the barite chimney that are less radiogenic than in seawater. In contrast, oxygen and multiple sulfur isotopes indicate that the fluid from which the barite precipitated contained residual sulfate that was affected by microbial sulfate reduction. A sulfate reduction zone at this site is further supported by the multiple sulfur isotopic composition of framboidal pyrite in the flow channel of the barite chimney and in the hydrothermal sediments in the barite field, as well as by low SO4 and elevated H2S concentrations in the venting fluids compared with conservative mixing values. We suggest that the mixing of ascending H2- and CH4-rich high-temperature fluids with percolating seawater fuels microbial sulfate reduction, which is subsequently recorded by barite formed at the seafloor in areas where the flow rate is sufficient. Thus, low-temperature precipitates in hydrothermal systems are promising sites to explore the interactions between the geosphere and biosphere in order to evaluate the microbial impact on these systems. © 2014 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/85185
Appears in Collections: 影响、适应和脆弱性
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作者单位: Department of Earth Science, Centre for Geobiology, University of Bergen, Bergen, Norway; Department of Geology, University of Johannesburg, Johannesburg, South Africa; Institut für Geologie und Paläontologie, Westfälische Wilhelms-Universität Münster, Münster, Germany; Centre for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Institut für Mineralogie, Westfälische Wilhelms-Universität Münster, Münster, Germany
Recommended Citation:
Eickmann B.,Thorseth I.H.,Peters M.,et al. Barite in hydrothermal environments as a recorder of subseafloor processes: A multiple-isotope study from the Loki's Castle vent field[J]. Geobiology,2014-01-01,12(4)