Clumped isotope signature of abiotic methane formed via Fischer-Tropsch catalysis and its implication in identifying the pathway of natural abiotic methane

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14594
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17050:Biogeosciences-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: ZHANG NAIZHONG 東京工業大学, 地球生命研究所, 研究員 (90782772)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: メタン / 同位体 / ガスハイドレート / 非生物学的メタン

Outline of Final Research Achievements

Understanding global methane cycles is one of the hot research topics as CH4 is a major greenhouse gas and an important energy resource. In this study, we have developed the most advanced methane clumped isotope analytical technique which could be used for exploring the natural CH4 formation and consumption pathways. We applied this method in two types of samples:
(1) natural gas hydrate recovered from the sediment of Japan Sea: our study sheds new light into the fundamental processes of methane clumped isotope effects in marine sediment environment and their potential to answer fundamental questions regarding the source and migration of CH4 found in naturally occurring hydrate accumulations.
(2) the laboratory synthesized abiotic CH4 via gaseous Fischer-Tropsch Type reactions: we discussed the mechanisms controlling isotopic changes during abiotic methanation and further applied our observations in better understanding the observed isotope patterns in natural abiotic CH4 reservoirs.

Free Research Field

地球科学

Academic Significance and Societal Importance of the Research Achievements

新しいメタン二重置換同位体分析法を適用することにより、地球規模のメタン循環や過去および将来の気候変動を制約するための有用性を実証した。また、実験室でのメタン生成実験成果は、地球や他の惑星における初期生命シグナルの探索に応用できる可能性がある。