Abstract
Abiotic synthesis of hydrocarbon-bearing fluids during geological processes has a significant impact on the evolution of both the Earth's biosphere and the solid Earth. Aqueous alteration of ultramafic rocks, i.e., serpentinization, which forms serpentinite, is one of the geological processes generating abiotic methane (CH4). However, abiotic CH4 generation is not limited to the serpentinization of mafic and ultramafic lithologies. Metasedimentary dolomitic marble from the Hida Belt, Japan, is characterized by the presence of forsterite-rich olivine (Fo~89–93), and olivine crystals contain abundant fluid inclusions (<1 to 10 μm in size). Raman spectroscopic analyses of olivine-hosted fluid inclusions found that both primary and secondary fluid inclusions contain CH4, lizardite/chrysotile, and brucite. This indicates that micro-scale interactions between COH fluid and host olivine produced CH4 through the reduction of CO2 by H2 released during local serpentinization within inclusions. Our observation implies that the dolomitic marble has the potential to be a key lithology for the synthesis and storage of abiotic CH4 in a shallower crustal portion of orogenic belts.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.