Updated on 2026/04/08

写真a

 
OHTA KENJI
 
Organization
School of Science Professor
Title
Professor
Homepage
http://kenjiohta-uhpr.sakura.ne.jp/Kenji_Ohtas_homepage/Welcome.html
External link

News & Topics

Degree

  • PhD ( Tokyo Institute of Technology )

Research Interests

  • Core

  • Mantle

  • High pressure and temperature experiment

  • Core-Mantle Boundary

  • Earth's Deep Interior

  • Thermal conductivity

  • Electrical conductivity

  • Sound velocity

Research Areas

  • Natural Science / Solid earth sciences  / High-Pressure Mineral Physics

Education

  • Tokyo Institute of Technology   Graduate School of Science and Technology   Department of Earth and Planetary Sciences

    2006.4 - 2010.9

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  • Tokyo Institute of Technology   School of Science   Department of Earth and Planetary Sciences

    2002.4 - 2006.3

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Research History

  • Institute of Science Tokyo   School of Science, Department of Earth and Planetary Sciences   Professor

    2025.12

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    Country：Japan

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  • Institute of Science Tokyo   Department of Earth and Planetary Sciences, School of Science   Associate Professor

    2024.10 - 2025.11

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    Country：Japan

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  • Tokyo Institute of Technology   School of Science, Department of Earth and Planetary Sciences   Associate Professor

    2017.7 - 2024.9

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  • Tokyo Institute of Technology   School of Science, Department of Earth and Planetary Sciences   Lecturer

    2013.11 - 2017.6

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  • Osaka University   Center for Quantum Science and Technology under Extreme Conditions   JSPS researcher (SPD)

    2011.4 - 2013.10

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  • Tokyo Institute of Technology   Department of Earth and Planetary Sciences, Graduate school of Science and Technology   JSPS researcher (PD)

    2010.10 - 2011.3

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  • Tokyo Institute of Technology   Graduate school of Science and Technology, Department of Earth and Planetary Sciences   JSPS researcher (DC1)

    2008.4 - 2010.9

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Professional Memberships

  • THE JAPAN SOCIETY OF HIGH PRESSURE SCIENCE AND TECHNOLOGY

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  • JAPAN GEOSCIENCE UNION

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Committee Memberships

  • SPring-8ユーザー協同体（SPRUC）地球惑星科学会   会長  

    2020.4 - 2024.3   

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  • SPring-8ユーザー協同体（SPRUC）地球惑星科学会   副会長  

    2018.4 - 2020.3   

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    Committee type：Academic society

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  • Frontiers in Science   Review Editor of Solid Earth Geophysics  

    2017.11   

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    Committee type：Academic society

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  • 日本高圧力学会   高圧力学会誌編集委員  

    2017.4 - 2020.9   

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    Committee type：Academic society

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  • Nature Publishing Group   Scientific Reports Editorial Board Member  

    2017.1 - 2020.6   

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    Committee type：Academic society

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Papers

  • Internally heated diamond-anvil cell technique using a boron-doped diamond as a resistive heater up to 100 GPa and 2400 K

    Yoshihiro Nagaya, Bunrin Natsui, Tatsuya Tamura, Kenji Ohta

    Review of Scientific Instruments   2026.4

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1063/5.0309204

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  • Temperature and pressure dependence on slip systems in MgO: Insights from large-strain deformation experiments using the rotational diamond anvil cell☆

    Keiya Ishimori, Shintaro Azuma, Kentaro Uesugi, Masahiro Yasutake, Keishi Okazaki, Bunrin Natsui, Eranga Gyanath Jayawickrama, Kenji Ohta

    PHYSICS OF THE EARTH AND PLANETARY INTERIORS   369   2025.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.pepi.2025.107461

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  • Crystallographic preferred orientation of (Mg,Fe)O up to 125 GPa inferred from torsional deformation experiments using a rotational diamond anvil cell Reviewed

    Bunrin Natsui, Shintaro Azuma, Keishi Okazaki, Kentaro Uesugi, Masahiro Yasutake, Saori Kawaguchi-Imada, Ryuichi Nomura, Kenji Ohta

    Physics of the Earth and Planetary Interiors   366   107392 - 107392   2025.9

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.pepi.2025.107392

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  • Thermal conductivity and evolution of the Earth's and Mars' cores Invited Reviewed

    Kenji Ohta, Kei Hirose

    Physics of the Earth and Planetary Interiors   366   107416 - 107416   2025.9

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.pepi.2025.107416

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  • High pressure–temperature picosecond acoustic measurements on Fe using an internal-resistive-heated diamond anvil cell Reviewed

    Yoshihiro Nagaya, Takashi Yagi, Ryoto Ebina, Kei Hirose, Manabu Kodama, Shuichiro Hirai, Kenji Ohta

    High Pressure Research   1 - 15   2025.6

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

    DOI： 10.1080/08957959.2025.2520559

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  • Electrical and thermal conductivities of Fe–Ni–Si alloy under core conditions: A reevaluation Reviewed

    Kenji Ohta, Hayato Inoue, Sho Suehiro, Kei Hirose, Saori Kawaguchi-Imada, Haruhiko Dekura

    Physics of the Earth and Planetary Interiors   363   107351 - 107351   2025.4

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    File： Ohta_Electrical and thermal conductivities of Fe–Ni–Si alloy under core conditions_2025PEPI.pdf

    DOI： 10.1016/j.pepi.2025.107351

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  • Observation of hot dense H2O phases through non-time-resolved and time-resolved x-ray diffraction measurements in a laser-heated diamond anvil cell Reviewed

    Kenta Iwamatsu, Yoshiyuki Okuda, Saori Kawaguchi-Imada, Kenji Ohta

    Physical Review B   2024.10

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    Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)  

    DOI： 10.1103/PhysRevB.110.134115

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  • Inversion of the temperature dependence of thermal conductivity of hcp iron under high pressure Reviewed

    Akira Hasegawa, Kenji Ohta, Takashi Yagi, Kei Hirose, Yuichiro Yamashita

    Scientific Reports   14 ( 1 )   2024.10

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    Authorship：Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    DOI： 10.1038/s41598-024-74110-3

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    Other Link： https://www.nature.com/articles/s41598-024-74110-3

  • Characterization of the lattice preferred orientation of hcp iron transformed from the single-crystal bcc phase in situ at high pressures up to 80 GPa Reviewed

    Yohan Park, Tatsuya Wakamatsu, Shintaro Azuma, Yu Nishihara, Kenji Ohta

    Physics and Chemistry of Minerals   51 ( 3 )   2024.8

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    Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    Abstract

    Studying the anisotropic physical properties of hexagonal closed-packed (hcp) iron is essential for understanding the properties of the Earth’s inner core related to the preferred orientation of the inner core materials suggested by seismic observations. Investigating the anisotropic physical properties of hcp iron requires (1) the synthesis of hcp iron samples that exhibit several distinctive types of strong lattice preferred orientation (LPO) and (2) the quantitative LPO analysis of the samples. Here, we report the distinctive LPO of hcp iron produced from single-crystal body-centered cubic (bcc) iron compressed along three different crystallographic orientations ([100], [110], and [111]) in a diamond anvil cell based on synchrotron multiangle X-ray diffraction measurements up to 80 GPa and 300 K. The orientation relationships between hcp iron and bcc iron are consistent with the Burgers orientation relationship with variant selection. We show that the present method is a way to synthesize hcp iron with strong and characteristic LPO, which is beneficial for experimentally evaluating the anisotropic physical properties of hcp iron.

    DOI： 10.1007/s00269-024-01293-6

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    Other Link： https://link.springer.com/article/10.1007/s00269-024-01293-6/fulltext.html

  • Electrical Conductivity of Dense MgSiO3 Melt Under Static Compression Reviewed

    Yoshiyuki Okuda, Kei Hirose, Kenji Ohta, Saori Kawaguchi‐Imada, Kenta Oka

    Geophysical Research Letters   2024.6

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1029/2024GL109741

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  • Submillisecond in situ X-ray diffraction measurement system with changing temperature and pressure using diamond anvil cells at BL10XU/SPring-8

    Saori Kawaguchi-Imada, Ryosuke Sinmyo, Kenji Ohta, Shogo Kawaguchi, Toshiyuki Kobayashi

    Journal of Synchrotron Radiation   31 ( Pt 2 )   343 - 354   2024.2

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1107/S1600577523010974

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  • Measuring the Electrical Resistivity of Liquid Iron to 1.4 Mbar Reviewed

    Kenji Ohta, Sho Suehiro, Saori I. Kawaguchi, Yoshiyuki Okuda, Tatsuya Wakamatsu, Kei Hirose, Yasuo Ohishi, Manabu Kodama, Shuichiro Hirai, Shintaro Azuma

    Physical Review Letters   130 ( 26 )   266301   2023.6

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    DOI： 10.1103/physrevlett.130.266301

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    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.130.266301/fulltext

  • Viscosity of Earth’s inner core constrained by Fe–Ni interdiffusion in Fe–Si alloy in an internal-resistive-heated diamond anvil cell Reviewed

    Yohan Park, Kyoko Yonemitsu, Kei Hirose, Yasuhiro Kuwayama, Shintaro Azuma, Kenji Ohta

    American Mineralogist   108 ( 6 )   1064 - 1071   2023.6

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Mineralogical Society of America  

    Abstract

    Diffusivity in iron (Fe) alloys at high pressures and temperatures imposes constraints on the transport properties of the inner core, such as viscosity. Because silicon (Si) is among the most likely candidates for light elements in the inner core, the presence of Si must be considered when studying diffusivity in the Earth’s inner core. In this study, we conducted diffusion experiments under pressures up to about 50 GPa using an internal-resistive-heated diamond-anvil cell (DAC) that ensures stable and homogeneous heating compared with a conventional laser-heated DAC and thus allows us to conduct more reliable diffusion experiments under high pressure. We determined the coefficients of Fe–nickel (Ni) interdiffusion in the Fe–Si 2 wt% alloy. The obtained diffusion coefficients follow a homologous temperature relationship derived from previous studies without considering Si. This indicates that the effect of Si on Fe–Ni interdiffusion is not significant. The upper limit of the viscosity of the inner core inferred from our results is low, indicating that the Lorentz force is a plausible mechanism to deform the inner core.

    DOI： 10.2138/am-2022-8541

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  • Ammonia and the ice giants Invited Reviewed

    Kenji Ohta

    Nature Physics   2023.5

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    Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    DOI： 10.1038/s41567-023-02081-9

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    Other Link： https://www.nature.com/articles/s41567-023-02081-9

  • Equations of state for B2 and bcc Fe1-Si

    Yoshihiro Nagaya, Hitoshi Gomi, Kenji Ohta, Kei Hirose

    Physics of the Earth and Planetary Interiors   107046 - 107046   2023.5

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    Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.pepi.2023.107046

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  • Thermal conductivity of platinum and periclase under extreme conditions of pressure and temperature

    Akira Hasegawa, Kenji Ohta, Takashi Yagi, Kei Hirose

    High Pressure Research   43 ( 1 )   1 - 13   2023.3

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    Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

    DOI： 10.1080/08957959.2023.2193892

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  • High-P–T impedance measurements using a laser-heated diamond anvil cell

    Yoshiyuki Okuda, Kenta Oka, Yusuke Kubota, Mako Inada, Naoki Kurita, Kenji Ohta, Kei Hirose

    Review of Scientific Instruments   93 ( 10 )   105103 - 105103   2022.10

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    Publishing type：Research paper (scientific journal)   Publisher：AIP Publishing  

    The electrical conductivity (EC) of minerals found on Earth and throughout the solar system is a fundamental transport property that is used to understand various dynamical phenomena in planetary interiors. High-pressure and high-temperature ( P–T) EC measurements are also an important tool for observing phase transitions. Impedance measurements can accurately measure the EC of a nonmetallic sample. In previous measurements under static conditions using a laser-heated diamond-anvil cell (LHDAC), only direct current resistance is measured, but this method overestimates the bulk sample resistance. Moreover, the previous methodology could only be applied to nontransparent samples in an LHDAC using infrared lasers, limiting the range of measurable composition. To the best of our knowledge, no in situ high- P–T EC measurements of transparent materials have been reported using LHDAC techniques. We developed a novel impedance measurement technique under high- P–T conditions in an LHDAC that applies to transparent samples. As a validation, we measured the EC of Mg0.9Fe0.1SiO3 bridgmanite up to 51 GPa and 2000 K and found that the results are consistent with those of previous studies. We also measured the EC values of sodium chloride to compare with those of previous studies, as well as those of cubic boron nitride and zirconia cement to quantify how well they insulate under high P–T conditions. This is the first report of the impedance and EC measurements of transparent minerals in an LHDAC, which allows the measurement of Fe-poor/-free materials, including the major constituents of the interiors of gas giants and icy planets, under extreme conditions.

    DOI： 10.1063/5.0097883

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  • Compressional wave velocity for iron hydrides to 100 gigapascals via picosecond acoustics Reviewed

    Tatsuya Wakamatsu, Kenji Ohta, Shoh Tagawa, Takashi Yagi, Kei Hirose, Yasuo Ohishi

    Physics and Chemistry of Minerals   49 ( 5 )   17   2022.5

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media {LLC}  

    DOI： 10.1007/s00269-022-01192-8

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    Other Link： https://link.springer.com/article/10.1007/s00269-022-01192-8/fulltext.html

  • Persistent Spin–Orbit Mott Insulating State in Highly Compressed Post-Perovskite CaIrO3 Reviewed

    Takuya Aoyama, Kenji Ohta, Katsuya Shimizu, Kenya Ohgushi

    Journal of the Physical Society of Japan   91 ( 4 )   2022.4

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    Publishing type：Research paper (scientific journal)   Publisher：Physical Society of Japan  

    DOI： 10.7566/jpsj.91.045003

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  • Low-spin ferric iron in primordial bridgmanite crystallized from a deep magma ocean Reviewed

    Yoshiyuki Okuda, Kenji Ohta, Yu Nishihara, Naohisa Hirao, Tatsuya Wakamatsu, Sho Suehiro, Saori I. Kawaguchi, Yasuo Ohishi

    Scientific Reports   11 ( 1 )   2021.12

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    Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    <title>Abstract</title>The crystallization of the magma ocean resulted in the present layered structure of the Earth’s mantle. An open question is the electronic spin state of iron in bridgmanite (the most abundant mineral on Earth) crystallized from a deep magma ocean, which has been neglected in the crystallization history of the entire magma ocean. Here, we performed energy-domain synchrotron Mössbauer spectroscopy measurements on two bridgmanite samples synthesized at different pressures using the same starting material (Mg0.78Fe0.13Al0.11Si0.94O3). The obtained Mössbauer spectra showed no evidence of low-spin ferric iron (Fe3+) from the bridgmanite sample synthesized at relatively low pressure of 25 gigapascals, while that directly synthesized at a higher pressure of 80 gigapascals contained a relatively large amount. This difference ought to derive from the large kinetic barrier of Fe3+ rearranging from pseudo-dodecahedral to octahedral sites with the high-spin to low-spin transition in experiments. Our results indicate a certain amount of low-spin Fe3+ in the lower mantle bridgmanite crystallized from an ancient magma ocean. We therefore conclude that primordial bridgmanite with low-spin Fe3+ dominated the deeper part of an ancient lower mantle, which would contribute to lower mantle heterogeneity preservation and call for modification of the terrestrial mantle thermal evolution scenarios.

    DOI： 10.1038/s41598-021-98991-w

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    Other Link： https://www.nature.com/articles/s41598-021-98991-w

  • Thermal conductivity of CaSiO3 perovskite at lower mantle conditions Reviewed

    Zhen Zhang, Dong-Bo Zhang, Kotaro Onga, Akira Hasegawa, Kenji Ohta, Kei Hirose, Renata M. Wentzcovitch

    Physical Review B   104 ( 18 )   2021.11

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    Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    DOI： 10.1103/PhysRevB.104.184101

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    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevB.104.184101/fulltext

  • Numerous chondritic impactors and oxidized magma ocean set Earth’s volatile depletion Reviewed

    Haruka Sakuraba, Hiroyuki Kurokawa, Hidenori Genda, Kenji Ohta

    Scientific Reports   11 ( 20894 )   2021.10

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    Abstract

    Earth’s surface environment is largely influenced by its budget of major volatile elements: carbon (C), nitrogen (N), and hydrogen (H). Although the volatiles on Earth are thought to have been delivered by chondritic materials, the elemental composition of the bulk silicate Earth (BSE) shows depletion in the order of N, C, and H. Previous studies have concluded that non-chondritic materials are needed for this depletion pattern. Here, we model the evolution of the volatile abundances in the atmosphere, oceans, crust, mantle, and core through the accretion history by considering elemental partitioning and impact erosion. We show that the BSE depletion pattern can be reproduced from continuous accretion of chondritic bodies by the partitioning of C into the core and H storage in the magma ocean in the main accretion stage and atmospheric erosion of N in the late accretion stage. This scenario requires a relatively oxidized magma ocean ($$\log _{10} f_{ { \mathrm{O } }_2}$$$$\gtrsim$$$${\mathrm{IW } }$$$$-2$$, where $$f_{ { \mathrm{O } }_2}$$ is the oxygen fugacity, $$\mathrm{IW}$$ is $$\log _{10} f_{ { \mathrm{O } }_2}^{\mathrm{IW } }$$, and $$f_{ { \mathrm{O } }_2}^{\mathrm{IW } }$$ is $$f_{ { \mathrm{O } }_2}$$ at the iron-wüstite buffer), the dominance of small impactors in the late accretion, and the storage of H and C in oceanic water and carbonate rocks in the late accretion stage, all of which are naturally expected from the formation of an Earth-sized planet in the habitable zone.

    DOI： 10.1038/s41598-021-99240-w

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    Other Link： https://www.nature.com/articles/s41598-021-99240-w

  • The thermal conductivity of the Earth's core and implications for its thermal and compositional evolution Invited Reviewed

    Kenji Ohta, Kei Hirose

    National Science Review   8 ( 4 )   2021.4

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    Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press ({OUP})  

    Abstract

    Determining the thermal conductivity of iron alloys at high pressures and temperatures are essential for understanding the thermal history and dynamics of the Earth's metallic cores. The authors summarize relevant high-pressure experiments using a diamond-anvil cell and discuss implications of high core conductivity for its thermal and compositional evolution.

    DOI： 10.1093/nsr/nwaa303

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    Other Link： http://academic.oup.com/nsr/article-pdf/8/4/nwaa303/38910237/nwaa303.pdf

  • A cylindrical SiC heater for an externally heated diamond anvil cell to 1500 K Reviewed

    Yoshiyuki Okuda, Seiji Kimura, Kenji Ohta, Yohan Park, Tatsuya Wakamatsu, Izumi Mashino, Kei Hirose

    Review of Scientific Instruments   92 ( 1 )   015119 - 015119   2021.1

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    Publishing type：Research paper (scientific journal)   Publisher：AIP Publishing  

    DOI： 10.1063/5.0036551

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  • Thermal conductivity of Fe-bearing post-perovskite in the Earth's lowermost mantle Reviewed

    Yoshiyuki Okuda, Kenji Ohta, Akira Hasegawa, Takashi Yagi, Kei Hirose, Saori I. Kawaguchi, Yasuo Ohishi

    Earth and Planetary Science Letters   547   116466 - 116466   2020.10

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    Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.epsl.2020.116466

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  • Laboratory-based x-ray computed tomography for 3D imaging of samples in a diamond anvil cell in situ at high pressures Reviewed

    Kenji Ohta, Tatsuya Wakamatsu, Manabu Kodama, Katsuyuki Kawamura, Shuichiro Hirai

    Review of Scientific Instruments   91 ( 9 )   093703 - 093703   2020.9

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    Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：AIP Publishing  

    DOI： 10.1063/5.0014486

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  • Anomalous compressibility in (Fe,Al)-bearing bridgmanite: implications for the spin state of iron Reviewed

    Yoshiyuki Okuda, Kenji Ohta, Ryosuke Sinmyo, Kei Hirose, Yasuo Ohishi

    PHYSICS AND CHEMISTRY OF MINERALS   47 ( 9 )   2020.9

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s00269-020-01109-3

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  • Resistivity saturation of hcp Fe-Si alloys in an internally heated diamond anvil cell: A key to assessing the Earth's core conductivity Reviewed

    Hayato Inoue, Sho Suehiro, Kenji Ohta, Kei Hirose, Yasuo Ohishi

    EARTH AND PLANETARY SCIENCE LETTERS   543   2020.8

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.epsl.2020.116357

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  • Stability of fcc phase FeH to 137 GPa Reviewed

    Chie Kato, Koichiro Umemoto, Kenji Ohta, Shoh Tagawa, Kei Hirose, Yasuo Ohishi

    American Mineralogist   105 ( 6 )   917 - 921   2020.6

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    Publishing type：Research paper (scientific journal)   Publisher：Mineralogical Society of America  

    <title>Abstract</title>
    We examined the crystal structure of FeHX (X~1) (FeH hereafter) at high pressure and temperature by X-ray diffraction up to 137 GPa. Results show that FeH adopts a face-centered cubic (fcc) structure at pressures of 43 to 137 GPa and temperatures of ~1000 to 2000 K. Our study revises a phase diagram of stoichiometric FeH in which fcc has a wider-than-expected stability field at high pressure and temperature. Based on our findings, the FeH end-member of the Fe-FeH system is expected to be stable in the fcc structure at the P-T conditions of the Earth's core, rather than in the double-hexagonal close packed (dhcp) structure as previously reported. We compared the experimentally determined unit-cell volumes of FeH with those from ab initio calculations. Additionally, we observed a change in compressibility at ~60 GPa, which could be attributed to a magnetic transition—an interpretation supported by our ab initio computations.

    DOI： 10.2138/am-2020-7153

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  • High-temperature electrical resistivity measurements of hcp iron to Mbar pressure in an internally resistive heated diamond anvil cell Reviewed

    Suehiro Sho, Wakamatsu Tatsuya, Ohta Kenji, Hirose Kei, Ohishi Yasuo

    HIGH PRESSURE RESEARCH   2019.11

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  • Hydrogen-Storing Salt NaCl(H-2) Synthesized at High Pressure and High Temperature Reviewed

    Takahiro Matsuoka, Shu Muraoka, Takahiro Ishikawa, Ken Niwa, Kenji Ohta, Naohisa Hirao, Saori Imada Kawaguchi, Yasuo Ohishi, Katsuya Shimizu, Shigeo Sasaki

    JOURNAL OF PHYSICAL CHEMISTRY C   123 ( 41 )   25074 - 25080   2019.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1021/acs.jpcc.9b06639

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  • Effect of spin transition of iron on the thermal conductivity of (Fe, Al)-bearing bridgmanite Reviewed

    Yoshiyuki Okuda, Kenji Ohta, Ryosuke Sinmyo, Kei Hirose, Takashi Yagi, Yasuo Ohishi

    Earth and Planetary Science Letters   520   188 - 198   2019.8

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.epsl.2019.05.042

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  • Combination of pulsed light heating thermoreflectance and laser-heated diamond anvil cell for in-situ high pressure-temperature thermal diffusivity measurements Reviewed

    Kenji Ohta

    Review of Scientific Instruments   90 ( 7 )   2019.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1063/1.5093343

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  • Composition and pressure dependence of lattice thermal conductivity of (Mg,Fe)O solid solutions Reviewed

    Hasegawa Akira, Ohta Kenji, Yagi Takashi, Hirose Kei, Okuda Yoshiyuki, Kondo Tadashi

    COMPTES RENDUS GEOSCIENCE   351 ( 2-3 )   229 - 235   2019.2

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.crte.2018.10.005

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  • Electrical resistivity of fcc phase iron hydrides at high pressures and temperatures Reviewed

    Kenji Ohta, Sho Suehiro, Kei Hirose, Yasuo Ohishi

    Comptes Rendus Geoscience   351 ( 2-3 )   147 - 153   2019.2

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    Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.crte.2018.05.004

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  • An Experimental Examination of Thermal Conductivity Anisotropy in hcp Iron Reviewed

    Kenji Ohta, Yu Nishihara, Yuki Sato, Kei Hirose, Takashi Yagi, Saori Kawaguchi, Naohisa Hirao, Yasuo Ohishi

    FRONTIERS IN EARTH SCIENCE   6   176 - 176   2018.11

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.3389/feart.2018.00176

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  • Measurements of sound velocity in iron–nickel alloys by femtosecond laser pulses in a diamond anvil cell Reviewed

    Tatsuya Wakamatsu, Kenji Ohta, Takashi Yagi, Kei Hirose, Yasuo Ohishi

    Physics and Chemistry of Minerals   45 ( 6 )   589 - 595   2018.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s00269-018-0944-3

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  • Lithium polyhydrides synthesized under high pressure and high temperature Reviewed

    Takahiro Matsuoka, Keiji Kuno, Kenji Ohta, Masafumi Sakata, Yuki Nakamoto, Naohisa Hirao, Yasuo Ohishi, Katsuya Shimizu, Tetsuji Kume, Shigeo Sasaki

    JOURNAL OF RAMAN SPECTROSCOPY   48 ( 9 )   1222 - 1228   2017.9

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    DOI： 10.1002/jrs.5183

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  • The effect of iron and aluminum incorporation on lattice thermal conductivity of bridgmanite at the Earth's lower mantle Reviewed

    Yoshiyuki Okuda, Kenji Ohta, Takashi Yagi, Ryosuke Sinmyo, Tatsuya Wakamatsu, Kei Hirose, Yasuo Ohishi

    EARTH AND PLANETARY SCIENCE LETTERS   474   25 - 31   2017.9

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    DOI： 10.1016/j.epsl.2017.06.022

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  • The influence of sulfur on the electrical resistivity of hcp iron: Implications for the core conductivity of Mars and Earth Reviewed

    Sho Suehiro, Kenji Ohta, Kei Hirose, Guillaume Morard, Yasuo Ohishi

    GEOPHYSICAL RESEARCH LETTERS   44 ( 16 )   8254 - 8259   2017.8

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    DOI： 10.1002/2017GL074021

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  • Thermal conductivity of ferropericlase in the Earth's lower mantle Reviewed

    Kenji Ohta, Takashi Yagi, Kei Hirose, Yasuo Ohishi

    EARTH AND PLANETARY SCIENCE LETTERS   465   29 - 37   2017.5

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    DOI： 10.1016/j.epsl.2017.02.030

    Web of Science

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  • Experimental determination of the electrical resistivity of iron at Earth's core conditions Reviewed

    Kenji Ohta, Yasuhiro Kuwayama, Kei Hirose, Katsuya Shimizu, Yasuo Ohishi

    NATURE   534 ( 7605 )   95 - +   2016.6

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    DOI： 10.1038/nature17957

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  • Compression of Fe-Si-H alloys to core pressures Reviewed

    Shoh Tagawa, Kenji Ohta, Kei Hirose, Chie Kato, Yasuo Ohishi

    GEOPHYSICAL RESEARCH LETTERS   43 ( 8 )   3686 - 3692   2016.4

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    DOI： 10.1002/2016GL068848

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  • Phase boundary of hot dense fluid hydrogen Reviewed

    Kenji Ohta, Kota Ichimaru, Mari Einaga, Sho Kawaguchi, Katsuya Shimizu, Takahiro Matsuoka, Naohisa Hirao, Yasuo Ohishi

    SCIENTIFIC REPORTS   5   2015.11

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    DOI： 10.1038/srep16560

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  • Heating of Li in hydrogen: possible synthesis of LiHx Reviewed

    K. Kuno, T. Matsuoka, T. Nakagawa, N. Hirao, Y. Ohishi, K. Shimizu, K. Takahama, K. Ohta, M. Sakata, Y. Nakamoto, T. Kume, S. Sasaki

    HIGH PRESSURE RESEARCH   35 ( 1 )   16 - 21   2015.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1080/08957959.2014.999677

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  • Measurements of lattice thermal conductivity of MgO to core-mantle boundary pressures Reviewed

    Saori Imada, Kenji Ohta, Takashi Yagi, Kei Hirose, Hideto Yoshida, Hiroko Nagahara

    GEOPHYSICAL RESEARCH LETTERS   41 ( 13 )   4542 - 4547   2014.7

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014GL060423

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  • Highly conductive iron-rich (Mg,Fe)O magnesiowustite and its stability in the Earth's lower mantle Reviewed

    K. Ohta, K. Fujino, Y. Kuwayama, T. Kondo, K. Shimizu, Y. Ohishi

    JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH   119 ( 6 )   4656 - 4665   2014.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1002/2014JB010972

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  • Thermal diffusivities of MgSiO3 and Al-bearing MgSiO3 perovskites Reviewed

    Kenji Ohta, Takashi Yagi, Kei Hirose

    AMERICAN MINERALOGIST   99 ( 1 )   94 - 97   2014.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.2138/am.2014.4598

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  • The high conductivity of iron and thermal evolution of the Earth's core Reviewed

    Hitoshi Gomi, Kenji Ohta, Kei Hirose, Stephane Labrosse, Razvan Caracas, Matthieu J. Verstraete, John W. Hernlund

    PHYSICS OF THE EARTH AND PLANETARY INTERIORS   224   88 - 103   2013.11

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.pepi.2013.07.010

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  • Experimental evidence of superionic conduction in H2O ice Reviewed

    Emiko Sugimura, Tetsuya Komabayashi, Kenji Ohta, Kei Hirose, Yasuo Ohishi, Leonid S. Dubrovinsky

    JOURNAL OF CHEMICAL PHYSICS   137 ( 19 )   2012.11

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1063/1.4766816

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  • Lattice thermal conductivity of MgSiO3 perovskite and post-perovskite at the core-mantle boundary Reviewed

    Kenji Ohta, Takashi Yagi, Naoyuki Taketoshi, Kei Hirose, Tetsuya Kornabayashi, Tetsuya Baba, Yasuo Ohishi, John Hernlund

    EARTH AND PLANETARY SCIENCE LETTERS   349   109 - 115   2012.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.epsl.2012.06.043

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  • Report on American Geophysical Union 2011 Fall Meeting

    OHTA Kenji

    The Review of High Pressure Science and Technology   22 ( 2 )   172 - 173   2012.5

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    Language：Japanese   Publisher：The Japan Society of High Pressure Science and Technology  

    DOI： 10.4131/jshpreview.22.172

    CiNii Books

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  • Experimental and Theoretical Evidence for Pressure-Induced Metallization in FeO with Rocksalt-Type Structure Reviewed

    Kenji Ohta, R. E. Cohen, Kei Hirose, Kristjan Haule, Katsuya Shimizu, Yasuo Ohishi

    PHYSICAL REVIEW LETTERS   108 ( 2 )   2012.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1103/PhysRevLett.108.026403

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  • Spin crossover, structural change, and metallization in NiAs-type FeO at high pressure Reviewed

    Haruka Ozawa, Kei Hirose, Kenji Ohta, Hirofumi Ishii, Nozomu Hiraoka, Yasuo Ohishi, Yusuke Seto

    PHYSICAL REVIEW B   84 ( 13 )   2011.10

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1103/PhysRevB.84.134417

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  • Thermal diffusivity measurement in a diamond anvil cell using a light pulse thermoreflectance technique Reviewed

    Takashi Yagi, Kenji Ohta, Kenichi Kobayashi, Naoyuki Taketoshi, Kei Hirose, Tetsuya Baba

    MEASUREMENT SCIENCE AND TECHNOLOGY   22 ( 2 )   2011.2

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1088/0957-0233/22/2/024011

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  • Monazite geochronology and geochemistry of meta-sediments in the Narryer Gneiss Complex, Western Australia: constraints on the tectonothermal history and provenance Reviewed

    Tsuyoshi Iizuka, Malcolm T. McCulloch, Tsuyoshi Komiya, Takazo Shibuya, Kenji Ohta, Haruka Ozawa, Emiko Sugimura, Kenneth D. Collerson

    CONTRIBUTIONS TO MINERALOGY AND PETROLOGY   160 ( 6 )   803 - 823   2010.12

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s00410-010-0508-0

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  • High-pressure experimental evidence for metal FeO with normal NiAs-type structure Reviewed

    Kenji Ohta, Kei Hirose, Katsuya Shimizu, Yasuo Ohishi

    PHYSICAL REVIEW B   82 ( 17 )   2010.11

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1103/PhysRevB.82.174120

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  • The electrical resistance measurements of (Mg,Fe)SiO3 perovskite at high pressures and implications for electronic spin transition of iron Reviewed

    Kenji Ohta, Kei Hirose, Katsuya Shimizu, Nagayoshi Sata, Yasuo Ohishi

    PHYSICS OF THE EARTH AND PLANETARY INTERIORS   180 ( 3-4 )   154 - 158   2010.6

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.pepi.2009.11.002

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  • Electrical conductivities of pyrolitic mantle and MORB materials up to the lowermost mantle conditions Reviewed

    Kenji Ohta, Kei Hirose, Masahiro Ichiki, Katsuya Shimizu, Nagayoshi Sata, Yasuo Ohishi

    EARTH AND PLANETARY SCIENCE LETTERS   289 ( 3-4 )   497 - 502   2010.1

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1016/j.epsl.2009.11.042

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  • The electrical conductivity of post-perovskite in Earth's D" layer Reviewed

    Kenji Ohta, Suzue Onoda, Kei Hirose, Ryosuke Sinmyo, Katsuya Shimizu, Nagayoshi Sata, Yasuo Ohishi, Akira Yasuhara

    SCIENCE   320 ( 5872 )   89 - 91   2008.4

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1126/science.1155148

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  • Phase transitions in pyrolite and MORB at lowermost mantle conditions: Implications for a MORB-rich pile above the core-mantle boundary Reviewed

    Kenji Ohta, Kei Hirose, Thorne Lay, Nagayoshi Sata, Yasuo Ohishi

    EARTH AND PLANETARY SCIENCE LETTERS   267 ( 1-2 )   107 - 117   2008.3

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    DOI： 10.1016/j.epsl.2007.11.037

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  • The effect of iron spin transition on electrical conductivity of perovskite and magnesiowustite Reviewed

    Kenji Ohta, Suzue Onoda, Kei Hirose, Katsuya Shimizu

    GEOCHIMICA ET COSMOCHIMICA ACTA   71 ( 15 )   A735 - A735   2007.8

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  • The effect of iron spin transition on electrical conductivity of (Mg,Fe)O magnesiowustite Reviewed

    Kenji Ohta, Kei Hirose, Suzue Onoda, Katsuya Shimizu

    PROCEEDINGS OF THE JAPAN ACADEMY SERIES B-PHYSICAL AND BIOLOGICAL SCIENCES   83 ( 3 )   97 - 100   2007.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.2183/pjab.83.97

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MISC

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Presentations

  • Inversion of the temperature dependence of thermal conductivity of hcp iron under high pressure Invited

    Kenji Ohta

    The Joint 28th AIRAPT and 60th EHPRG International Conference 2023  2023.7 

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    Event date： 2023.7

    Language：English  

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  • Measuring the electrical resistivity of liquid iron at the pressures of planetary cores Invited

    Kenji Ohta

    Study of Earth's Deep Interior (SEDI) 2022@Zurich  2022.7 

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    Event date： 2022.7

    Language：English   Presentation type：Oral presentation (invited, special)  

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  • Measurements of high pressure-temperature thermal conductivity of the Earth's lower mantle minerals in a laser-heated diamond anvil cell Invited

    OHTA Kenji, Akira Hasegawa, Takashi Yagi, Yoshiyuki Okuda, Kotaro Onga, Kei Hirose, Yasuo Ohishi

    JpGU 2019  2019.5 

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  • Experimental determination of the electrical and thermal conductivity of iron at Earth’s core conditions Invited International conference

    OHTA Kenji

    AGU 2016 Fall Meeting  2016.12 

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  • Lattice thermal conductivity of lower mantle minerals Invited International conference

    OHTA Kenji

    The 26th V.M. Goldschmidt Conference  2016.5 

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  • Experimental determination of the thermal and electrical conductivity of iron at Earth’s core conditions Invited International conference

    OHTA Kenji

    High Pressure Research at Gordon Research Conference 2018  2018.7 

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  • Experimentally inferred thermal conductivity of planetary cores Invited International conference

    OHTA Kenji

    Japan Geoscience Union Meeting 2018  2018.5 

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  • Phase transitions in pyrolitic mantle and MORB materials and their electrical conductivities at lowermost mantle Invited International conference

    OHTA Kenji

    American Geophysical Union Fall Meeting  2010.12 

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  • Lattice thermal conductivity of MgSiO3 perovskite and post-perovskite at the core-mantle boundary Invited International conference

    OHTA Kenji

    American Geophysical Union Fall Meeting  2011.12 

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  • Experimental constraints on electrical and thermal conductivity of the core-mantle boundary region Invited International conference

    OHTA Kenji

    Interior of the Earth, Gordon Research Conference  2013.6 

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  • Spin crossover, Structural Change, and Metallization in FeO under High Pressure Invited International conference

    OHTA Kenji

    High Pressure, Research at Gordon Research Conference  2012.6 

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    Language：English   Presentation type：Oral presentation (invited, special)  

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  • Measurements of electrical and thermal conductivity of iron under Earth’s core conditions Invited International conference

    OHTA Kenji

    American Geophysical Union, 2014 Fall meeting  2014.12 

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    Language：English   Presentation type：Oral presentation (invited, special)  

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  • Experimental constraints on thermal conductivity of the core-mantle boundary region Invited International conference

    OHTA Kenji

    The 14th symposium of SEDI (Study of Deep Earth Interior)  2014.8 

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Awards

  • Education Award for young faculty at School of Science

    2019.11   School of Science, Tokyo Institute of Technology  

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  • Alvin Van Valkenburg Award

    2018.7   AIRAPT  

    OHTA Kenji

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  • 日本高圧力学会奨励賞

    2015.11   日本高圧力学会  

    太田 健二

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  • Award for challenging research

    2014.8   Tokyo Institute of Technology  

    OHTA Kenji

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  • The Doornbos Memorial Prize

    2014.8   International Union of Geodesy and Geophysics (IUGG)  

    OHTA Kenji

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  • Graduate student research award (Honorable mention)

    2011.12   American Geophysical Union (AGU)  

    OHTA Kenji

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  • Tejima Award, PhD. Thesis Award

    2011.2   Tokyo Institute of Technology  

    OHTA Kenji

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Research Projects

  • 回転式DACによる超高圧高温変形実験から明らかにする深部スラブの変形特性

    Grant number：24K00729  2024.4 - 2028.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    東 真太郎, 太田 健二, 岡崎 啓史, 安武 正展

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    Grant amount：\18590000 （ Direct Cost: \14300000 、 Indirect Cost：\4290000 ）

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  • Solid State Ionics under extreme conditions of Earth's deep interior

    Grant number：24H00266  2024.4 - 2028.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

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    Grant amount：\47840000 （ Direct Cost: \36800000 、 Indirect Cost：\11040000 ）

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  • Verification of superionic state of the subducting oceanic plate by high-pressure experiments, theoretical calculations, and electromagnetic sounding analysis

    Grant number：23KK0061  2023.9 - 2027.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Fund for the Promotion of Joint International Research (International Collaborative Research)

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    Grant amount：\20930000 （ Direct Cost: \16100000 、 Indirect Cost：\4830000 ）

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  • Light elements in the Earth's core revealed by ultrahigh-pressure experiments

    Grant number：21H04968  2021.5 - 2026.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Specially Promoted Research

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    Grant amount：\628810000 （ Direct Cost: \483700000 、 Indirect Cost：\145110000 ）

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  • 高圧下の鉄合金の特性とコアの軽元素組成の制約

    Grant number：21H04506  2021.4 - 2022.3

    日本学術振興会  科学研究費助成事業  基盤研究(A)

    廣瀬 敬, 太田 健二, 坂本 直哉, 梅本 幸一郎, 圦本 尚義

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    Grant amount：\41990000 （ Direct Cost: \32300000 、 Indirect Cost：\9690000 ）

    結果的に１ヶ月半という期間となった本課題について、以下の７つの研究を進めた。１）SPring-8のビームラインBL43LXUにおけるX線非弾性散乱法を使った液体FeOの縦波速度測定に関し、過去の測定データの解析と６月のビームタイムに向けた実験準備を行った。また２）同じくSPring-8のビームラインBL10XUにおけるX線回折測定によって、超高圧高温まで 固体Feの格子体積を求め、状態方程式を決定するためのデータを解析した。さらに３）固体FeHの高圧高温下における体積データから高温の状態方程式を作成するとともに、４）Fe-FeH系の高圧高温実験を行って、状態図の作成を試みた。クライオ二次イオン質量分析法を使って、回収試料の三次元水素濃度マッピングを行い、水素の定量分析法の開発を進めた。５）Fe-Si系の実験も200万気圧までやり直し、共融点の化学組成の圧力変化を正確に見積もった。６）コア形成時の金属-シリケイト分配についても二次イオン質量分析法を使った定量を行い、水素（水）が系に含まれることにより、硫黄と炭素の分配係数が大きく変化する（メタルに分配されにくくなる）ことを見つけた。最後に、７）沈み込んでいく海洋プレート（スラブ）は水をコアーマントル境界まで輸送し、その高温環境下で脱水した水はコアの金属鉄と化学反応を起こして、鉄水酸化物などを作ると従来考えられていた。ところが今回二次イオン質量分析法を使って行った、含水SiO2相の含水量を定量する実験によって、スラブが運んだ水は脱水せず、コアーマントル境界域に水を供給しないことが明らかになった。

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  • 地球外核・内核の伝導特性の実験的制約による地球熱進化の理解

    2019.4 - 2023.3

    JSPS  基盤研究（A) 

    太田 健二

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    Authorship：Principal investigator  Grant type：Competitive

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  • 超高温・高圧条件における地球深部物質の体積熱容量計測技術の開発

    Grant number：19H01995  2019.4 - 2023.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    八木 貴志, 太田 健二

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    Grant amount：\17680000 （ Direct Cost: \13600000 、 Indirect Cost：\4080000 ）

    地球核およびマントル物質の体積熱容量を温度軸と圧力軸の両面から依存性を明らかにすることを目的に、高温・高圧条件における体積熱容量の計測技術の開発と、地球深部物質の熱物性計測を進めた。高温加熱用レーザの1台の修理が完了し、従来よりもさらに高温環境の実現が可能となった。マントル鉱物の熱伝導率の評価として、MgOペリクレース相の評価を行い、12 GPaにおいて最高3169 Kにおける計測に成功した。また最高圧力140 GPaにおいては約2000 Kでの熱伝導率を計測した。この結果からMgOペリクレースの熱伝導率の密度および温度微分係数を決定しそれぞれ4.4および-0.62の結果を得た。また高温高圧熱伝導率計測において、レーザ吸収体や圧力計測用に用いられるPtの高温高圧熱伝導率についても評価を行い、κ(W/m/K)= 0.953P/GPa+0.0137T/K+61.8 <～1850 K, 125 GPa>の関係式を得た。通常の固体物質は温度増加によりフォノン散乱が増加することから熱伝導率は負の温度依存性を持つが、Ptの熱伝導率は、常温で正の温度依存性を有することが知られている。今回の結果により、高圧ではこの正の温度依存性がより顕著になることが初めて明らかとなった。またピコ秒レーザ弾性波測定による水素化鉄の100 GPaまでの音速計測結果から地球内核条件（360 GPa、5500 K）における弾性波の予想値を算出できた。体積熱容量計測についても開発を進め、基礎的な測定条件におけるデータ解析を進めた。

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  • 高温高圧実験で探る地球中心核の熱伝導率と地球熱進化

    2017.4 - 2020.3

    日本学術振興会  若手研究（A) 

    太田 健二

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    Authorship：Principal investigator  Grant type：Competitive

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  • Dynamic behaviour of core and mantle materials

    2015.6 - 2020.3

    JSPS  Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area) 

    Takashi Yoshino

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    Grant type：Competitive

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  • 高圧変形実験で探る地球中心核の異方性

    2015.4 - 2019.3

    日本学術振興会  基盤研究(B) 

    西原遊

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  • 極限環境の熱伝導率計測技術による地球コア内部の熱移動の解明

    2014.4 - 2018.3

    日本学術振興会  基盤研究（A) 

    八木貴志

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    Grant type：Competitive

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  • Electrical and thermal conduction properties of Earth's core

    2014.4 - 2017.3

    JSPS  Grant-in-Aid for Young Scientists (A) 

    OHTA Kenji

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    Authorship：Principal investigator  Grant type：Competitive

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  • 高温高圧下でのマントル鉱物、水素の熱・電気伝導率測定：惑星内部の輸送特性の解明

    2011.4 - 2013.10

    日本学術振興会  特別研究員奨励費 

    太田 健二

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    Authorship：Principal investigator  Grant type：Competitive

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  • 地球深部物質の電気伝導度測定

    2008.4 - 2011.3

    日本学術振興会  特別研究員奨励費 

    太田 健二

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    Authorship：Principal investigator  Grant type：Competitive

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Teaching Experience

  • 地球科学序論

    Institution：東京工業大学

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  • 地球物質学

    Institution：東京工業大学

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  • 地惑実験

    Institution：東京工業大学

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  • 熱力学

    Institution：東京工業大学

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  • 地惑巡検

    Institution：東京工業大学

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