Japan Geoscience Union Meeting 2021

Presentation information

[J] Oral

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS21] Chemosynthetic community and mud volcano: biology, geochemistry, and geophysics of fluid discharge

Thu. Jun 3, 2021 10:45 AM - 12:15 PM Ch.25 (Zoom Room 25)

convener:Yusuke Miyajima(Geomicrobiology Research Group, Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology), Kayama Hiromi WATANABE(Japan Agency for Marine-Earth Science and Technology), Akira Ijiri(Japan Agency for Marine-Earth Science and Technology), Tomohiro Toki(Faculty of Science, University of the Ryukyus), Chairperson:Yusuke Miyajima(Geomicrobiology Research Group, Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology), Hiromi Kayama WATANABE(Japan Agency for Marine-Earth Science and Technology)

11:00 AM - 11:15 AM

[MIS21-02] Methanogenesis in deep subseafloor sediments −living methanogen diversity, distribution, physiology and activity−

★Invited Papers

*Taiki Katayama1, Hideyoshi Yoshioka1, Masanori Kaneko1, Susumu Sakata1, Miki Amo2, Tetsuya Fujii2 (1.National Institute of Advanced Industrial Science and Technology, 2.Japan Oil, Gas and Metals National Corporation)

Keywords:gas hydrate, biogenic methane formation, cultivation, deep subseafloor sediment

Gas hydrates deposited in subseafloor sediments are considered to be the Earth’s largest natural gas reservoir of biogenic methane based on geochemical analyses. However, thus far, viable methanogens, microorganisms that are responsible for biogenic methane formation, have been poorly obtained and characterized. Characterization of living methanogens in subseafloor sediments at hydrate sites are fundamental for understanding biogenic gas hydrate formation and our estimations of gas hydrate reserves. We performed cultivation dependent and independent analyses of microorganisms in the hydrate-bearing sediments from the eastern Nankai Trough. In this presentation, I will show previously overlooked phylogenetic and metabolic diversity of viable methanogens and importance of methylotrophic methanogenesis and discuss their depth-related profiles. This study was part of the Research Consortium for Methane Hydrate Resources program in Japan (MH21 Research Consortium).