Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

B (Biogeosciences) » B-BG Biogeosciences & Geosphere-Biosphere Interactions

[B-BG02] Interrelation between Life, Water, Mineral, and Atmosphere

Mon. May 21, 2018 10:45 AM - 12:15 PM 101 (1F International Conference Hall, Makuhari Messe)

convener:Ken Takai(Extremobiosphere Research Center, Japan Agency for Marine-Earth Science & Technology), Kentaro Nakamura(Department of Systems Innovation, School of Engineering, University of Tokyo), Yuichiro Ueno(東京工業大学大学院地球惑星科学専攻, 共同), Yohey Suzuki(Graduate School of Science, The University of Tokyo), Chairperson:Ueno Yuichiro(Tokyo Tech.), Nakamura Kentaro(Univ. Tokyo)

10:45 AM - 11:00 AM

[BBG02-06] Hydrogen generation mechanism on the magnetite surface with hydrothermal reaction

*Tomoya Tamura1, Ryo Sugaya1, Atsushi Kyono1 (1.Graduate School of Life and Environmental Sciences, University of Tsukuba)

Keywords:Magnetite, Hydrogen generation, TEM

To elucidate the hydrogen generation mechanism on the magnetite surface during serpentinization, the observations of surface and chemical states of hydrothermally reacted magnetite were conducted by the electron microscope techniques. Hydrogen was detected with methyleneblue colorimetry. The SEM observations showed that the (100) plane was readily dissolved with the hydrothermal reaction. The electron diffraction patterns indicated that the shallow depth of the (100) plane was transformed to maghemite. The TEM analysis revealed that the precipitates on the (111) plane were composed of hematite and goethite. It is assumed that these precipitates were grown from the dissolved iron ion from (100) plane. Consequently, the hydrogen generation occurs with reduction of the H2O.