Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Oral

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS08] Drilling Earth Science

Tue. May 22, 2018 9:00 AM - 10:30 AM Convention Hall B (CH-B) (2F International Conference Hall, Makuhari Messe)

convener:Yasuhiro Yamada(Japan Agency for Marine-Earth Science and Technology (JAMSTEC), R&D Center for Ocean Drilling Science (ODS)), Junichiro Kuroda(Department of Ocean Floor Geoscience, Atmosphere and Ocean Research Institute, the University of Tokyo), Kohtaro Ujiie(筑波大学生命環境系, 共同), Yusuke Suganuma(National institute of Polar Research), Chairperson:Ujiie Kohtaro(Graduate School of Life and Environmental Sciences, University of Tsukuba), Yamada Yasuhiro(JAMSTEC)

9:15 AM - 9:30 AM

[MIS08-02] Deep Igneous Rock Biosphere Unveiled beneath Ultra-Oligotrophic South Pacific Gyre Sediments

*Yohey Suzuki1 (1.Graduate School of Science, The University of Tokyo)

Keywords:Subsurface microbiology, Basaltic basement

The upper oceanic crust is composed of basaltic lava and overlying sediment. The aged basaltic basement is considered to be inhospitable for microbial life, because the apparent energy source is lacking. By drilling >10-million-years-old basaltic basement underneath oxygenated, ultra-oligotrophic sediments in South Pacific Gyre, microbial communities were profiled by single-gene analysis. The dominant occurrence of microorganisms phylogenetically affiliated within methanotrophic lineages suggests that the crustal biosphere is likely fueled by methane in the old basaltic basement. The dense colonization of endolithic life was observed for the first time in the deep basaltic basement. Given that the areal coverage of basaltic basement overlain by oxygenated sediments reaches up to 25% on Earth, we conclude that microbial life is widespread in the upper oceanic crust.