Unraveling abiotic organic synthesis pathways in the mafic crust of mid- ocean ridges

• 成果类型: Article
• 署名作者: Nan, Jingbo; Peng, Xiaotong; Plumper, Oliver; ten Have, Iris C.; Lu, Jing- Guang; Liu, Qian-Bao; Li, Shao-Lin; Hu, Yingjie; Liu, Yu; Shen, Zhen; Yao, Weiqi; Tao, Renbiao; Preiner, Martina; Luo, Yongxiang
• 署名单位: Chinese Academy of Sciences; Institute of Deep-Sea Science & Engineering, CAS; Chinese Academy of Sciences; Utrecht University; Utrecht University; Macau University of Science & Technology; Macau University of Science & Technology; Nanjing Xiaozhuang University; China University of Mining & Technology; Southern University of Science & Technology; Max Planck Society; Philipps University Marburg; Max Planck Society
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9969
• DOI: 10.1073/pnas.2308684121
• 发表日期: 2024-10-22
• 关键词: fischer-tropsch synthesis; carbon; serpentinites; fluxes; time; iron; hydrocarbons; SURFACES; catalyst; water

摘要

The aqueous alteration of the oceanic lithosphere provides significant energy that impacts the synthesis and diversity of organic compounds, which are crucial for the deep carbon cycle and may have provided the first building blocks for life. Although abiotic organic synthesis has been documented in mantle- derived rocks, the formation mechanisms and complexity of organic compounds in crustal rocks remain largely unknown. Here, we show the specific association of aliphatic carbonaceous matter with Fe oxyhydroxides in mafic crustal rocks of the Southwest Indian Ridge (SWIR). We determine potential Fe- based pathways for abiotic organic synthesis from CO2 and H2 using multimodal and molecular nano- geochemical tools. Quantum mechanical modeling is further employed to constrain the catalytical activity of Fe oxyhydroxides, revealing that the catalytic cycle of hydrogen may play a key role in carbon-carbon bond formation. This approach offers the possibility of interpreting physicochemical organic formation and condensation mechanisms at an atomic scale. The findings expand our knowledge of the existence of abiotic organic carbon in the oceanic crustal rocks and emphasize the mafic oceanic crust of the SWIR as a potential site for low- temperature abiotic organic synthesis.