Sulfur Isotope Geochemistry of Ice Wedges, Northeastern Siberia
학위논문(석사) -- 서울대학교대학원 : 자연과학대학 지구환경과학부, 2023. 8. 심민섭. With its unique stable isotope ratio and involvement in various biogeochemical processes, sulfur serves as a valuable paleoenvironmental proxy. Ice wedges have recently been evaluated as archives for aerosols, precipitation, and organic matter, se...
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| Other Authors: | , , |
| Format: | Doctoral or Postdoctoral Thesis |
| Language: | English |
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서울대학교 대학원
2023
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| Online Access: | https://hdl.handle.net/10371/197330 https://dcollection.snu.ac.kr/common/orgView/000000179219 |
| Summary: | 학위논문(석사) -- 서울대학교대학원 : 자연과학대학 지구환경과학부, 2023. 8. 심민섭. With its unique stable isotope ratio and involvement in various biogeochemical processes, sulfur serves as a valuable paleoenvironmental proxy. Ice wedges have recently been evaluated as archives for aerosols, precipitation, and organic matter, serving as useful archives of paleoenvironmental information. However, sulfur isotopic compositions in ice wedges have not yet been comprehensively explored or understood. This study presents the first sulfur isotope geochemical data from the ice wedge of Northeastern Siberia. The samples were collected from the Yakutsk (Cyuie, Churapcha, Syrdakh), Zyryanka, and Batagay regions and separated into dissolved sulfate, particulate organic matter (POM), and lithic particles. The sulfur isotopic composition from the different areas shows consistent trends in each component. Yakutsk showed significant enrichment of more than 6‰ compared to the other study regions. Despite their distance, Cyuie, Churapcha, and Syrdakh in the Yakutsk region have similar sulfur isotopic compositions but are differed from values from the Zyryanka and Batagay regions. This observation suggests a potential influence of the local bedrock on sulfur sources. Sulfur isotopic compositions between modern precipitation, plant sulfur, and ice wedges in Yakutsk and the upper and lower Batagay sections could not find temporal variations in sulfur isotopic composition. Instead, the differences observed within the same ice wedge suggest that while the source of sulfur-containing materials remains consistent, the ice wedge may have temporal sensitivity to glaciation. In-house freezing experiments and sulfide assay in the ice wedge found that there was no fractionation during the freezing process and by sulfate-reducing microorganisms within the ice wedge, indicating that the sulfur contained in the ice wedge preserves the isotopic composition of the source material. This study establishes an experimental method for analyzing sulfur isotope analysis in ice ... |
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