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YAMAMOTO Yuzuru
Graduate School of Science / Division of Planetology
Professor

Researcher basic information

■ Research Keyword
  • Liquefaction
  • Submarine slope failure
  • Subduction zone
  • Structural Geology
  • Tectonics
■ Research Areas
  • Natural sciences / Solid earth science
  • Social infrastructure (civil Engineering, architecture, disaster prevention) / Disaster prevention engineering
■ Committee History
  • Jan. 2023 - Present, 日本地球惑星科学連合, 巡検委員
  • Jan. 2021 - Present, IODP, Science Evaluation Panel

Research activity information

■ Award
  • May 2024 Japan Geoscience Union Meeting 2024 固体地球科学セクション学生優秀発表賞, Consolidation characteristics of offshore sediments in the Christiana, Santorini, and Kolumbo volcanic field, Greece (IODP Expedition 398)
    吉本 剛瑠, 山本 由弦, Manga Michael, Beethe Sarah, McIntosh Iona, Woodhouse Adam, 千代延 俊, Koukousioura Olga, Druitt Tim, Kutterolf Steffen, Ronge Thomas, IODP Ex, Scientists
    共同研究・競争的資金等の業績IDIRI

  • Sep. 2023 日本地質学会, 日本地質学会学生優秀発表賞, トンネル内で盤ぶくれを引き起こす泥質岩の最高経験温度
    関山優希, 望月一磨, 今井啓文, 上野 光, 山本由弦
    共同研究・競争的資金等の業績IDIRI

  • May 2022 Japan Geoscience Union Meeting 2022 固体地球科学セクション学生優秀発表賞, Variation of consolidation characteristics among 3 facies in Miyazaki forearc basin, SW Japan
    吉本剛瑠, 千代延 俊, 大森 康智, 鈴木 雄大, 張 鋒, 山本 由弦

  • Oct. 2013 ISSMMTC, Best Paper Award, Along-strike migration of intermittent submarine slope failures at subduction margins: geological evidence from the Chikura Group, central Japan.
    YAMAMOTO Yuzuru

  • Sep. 2011 Geological Society of Japan, Best Paper Award, Formation of chaotic rock-units during primary accretion processes: examples from the Miura–Boso accretionary complex, Central Japan
    YAMAMOTO Yuzuru, NIDAIRA Manami, OHTA Yasufumi, OGAWA Yujiro

  • Mar. 2003 筑波大学, Best Paper award, Deformation history and related change of physical properties in shallow part of accretionary prism.
    YAMAMOTO Yuzuru

■ Paper
  • T.A. Ronge, S. Kutterolf, T.I. Fernandez-Perez, M. Manga, A. Metcalfe, J. Preine, M. Tominaga, A. Woodhouse, J. Yeon, T.H. Druitt, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, Y. Yamamoto
    International Ocean Discovery Program, Dec. 2024, Proceedings of the International Ocean Discovery Program
    [Refereed]
    In book

  • Takeshi Hanyu, Nobukazu Seama, Katsuya Kaneko, Qing Chang, Reina Nakaoka, Koji Kiyosugi, Yuzuru Yamamoto, Tetsuo Matsuno, Keiko Suzuki-Kamata, Yoshiyuki Tatsumi
    Aug. 2024, Communications Earth & Environment, 5, 428, English
    [Refereed]
    Scientific journal

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • S. Kutterolf, T.H. Druitt, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • T.H. Druitt, S. Kutterolf, T.A. Ronge, S. Beethe, A. Bernard, C. Berthod, H. Chen, S. Chiyonobu, A. Clark, S. DeBari, T.I. Fernandez Perez, R. Gertisser, C. Hübscher, R.M. Johnston, C. Jones, K.B. Joshi, G. Kletetschka, O. Koukousioura, X. Li, M. Manga, M. McCanta, I. McIntosh, A. Morris, P. Nomikou, K. Pank, A. Peccia, P.N. Polymenakou, J. Preine, M. Tominaga, A. Woodhouse, Y. Yamamoto
    International Ocean Discovery Program, Jul. 2024, Proceedings of the International Ocean Discovery Program
    International conference proceedings

  • Jonas Preine, Jens Karstens, Christian Hübscher, Tim Druitt, Steffen Kutterolf, Paraskevi Nomikou, Michael Manga, Ralf Gertisser, Katharina Pank, Sarah Beethe, Carole Berthod, Gareth Crutchley, Iona McIntosh, Thomas Ronge, Masako Tominaga, Acacia Clark, Susan DeBari, Raymond Johnston, Zenon Mateo, Ally Peccia, Christopher Jones, Günther Kletetschka, Abigail Metcalfe, Alexis Bernard, Hehe Chen, Shun Chiyonobu, Tatiana Fernandez-Perez, Kumar Batuk Joshi, Olga Koukousioura, Molly McCanta, Antony Morris, Paraskevi Polymenakou, Adam Woodhouse, Yuzuru Yamamoto, Kuo-Lung Wang, Hao-Yang Lee, Xiaohui Li, Dimitrios Papanikolaou
    Abstract Caldera-forming eruptions of silicic volcanic systems are among the most devastating events on Earth. By contrast, post-collapse volcanic activity initiating new caldera cycles is generally considered less hazardous. Formed after Santorini’s latest caldera-forming eruption of ~1600 bce, the Kameni Volcano in the southern Aegean Sea enables the eruptive evolution of a recharging multi-cyclic caldera to be reconstructed. Kameni’s eruptive record has been documented by onshore products and historical descriptions of mainly effusive eruptions dating back to 197 bce. Here we combine high-resolution seismic reflection data with cored lithologies from International Ocean Discovery Program Expedition 398 at four sites to determine the submarine architecture and volcanic history of intra-caldera deposits from Kameni. Our shore-crossing analysis reveals the deposits of a submarine explosive eruption that produced up to 3.1 km3 of pumice and ash, which we relate to a historical eruption in 726 ce. The estimated volcanic explosivity index of magnitude 5 exceeds previously considered worst-case eruptive scenarios for Santorini. Our finding that the Santorini caldera is capable of producing large explosive eruptions at an early stage in the caldera cycle implies an elevated hazard potential for the eastern Mediterranean region, and potentially for other recharging silicic calderas.
    Springer Science and Business Media LLC, Mar. 2024, Nature Geoscience, 17(4) (4), 323 - 331, English
    [Refereed]
    Scientific journal

  • Mikito Furuichi, Jian Chen, Daisuke Nishiura, Ryuta Arai, Yuzuru Yamamoto, Satoshi Ide
    Elsevier BV, Mar. 2024, Tectonophysics, 874, 230230 - 230230, English
    [Refereed]
    Scientific journal

  • Mari Hamahashi, Hironori Otsuka, Yoshiaki Suzuki, Jun Arimoto, Tetsuo Matsuno, Nobukazu Seama, Yuzuru Yamamoto, Hiroko Sugioka, Stephen A. Bowden, Satoshi Shimizu, Hikaru Iwamaru, Mamoru Sano, Keita Suzuki, Katsuya Kaneko, Kazuo Nakahigashi, Yoshiyuki Tatsumi
    Abstract The Osaka Bay is situated at a seismically active region north of the Median Tectonic Line and east of Awaji Island in western Japan, known as part of the Kinki Triangle and the Niigata–Kobe Tectonic Zone. Dense distribution of active faults and high geodetic strain rates characterize the region, posing a major seismic hazard potential to the coastal and metropolitan areas of the Kansai region. To investigate the shallow structure and recent deformation history of active faults in the Osaka Bay, we acquired 15 high-resolution seismic profiles using a Mini-GI airgun and a Boomer as active sources, together with multi-beam bathymetry data across the Osaka Bay Fault. Our seismic sections image a ~ 0.1 to 3.7 km-wide asymmetric anticline forelimb above the Osaka Bay Fault at shallow depths, coupled with a ~ 2.6 km-wide syncline to the west, and a broad, ~ 11 km-wide syncline in the footwall to the east. The synclinal axial surface at shallow depths measured in this study ranges 75°–89°. We observe the vertical displacement of the Osaka Bay Fault increasing northwards along strike. The sediment thickness on the hanging wall, however, is variable, modified by non-tectonic processes such as by tidal currents, affecting the geometry of growth strata. The most recent deformation by the Osaka Bay Fault reaches to near the seafloor by active folding, with large vertical offsets of 8–14 m over the last ~ 11 ka, and 5–11 m over the last ~ 5 ka. By combining with previously reported borehole age data, the average uplift rate on the Osaka Bay Fault is estimated to be ~ 1.0 to 1.7 m/ka during the Latest Pleistocene to Holocene. The inferred slip of the Osaka Bay Fault during the Holocene is likely to account for > 5% of the regional geodetic strain accumulation within the Kinki Triangle. Further studies to evaluate the Holocene slip rates of regional faults are necessary to assess the seismic hazards and the internal strain budgets within the Kinki Triangle and the Niigata–Kobe Tectonic Zone. Graphical abstract
    Springer Science and Business Media LLC, Feb. 2024, Progress in Earth and Planetary Science, 11(1) (1), English
    [Refereed]
    Scientific journal

  • Tim Druitt, Steffen Kutterolf, Thomas A. Ronge, Christian Hübscher, Paraskevi Nomikou, Jonas Preine, Ralf Gertisser, Jens Karstens, Jörg Keller, Olga Koukousioura, Michael Manga, Abigail Metcalfe, Molly McCanta, Iona McIntosh, Katharina Pank, Adam Woodhouse, Sarah Beethe, Carole Berthod, Shun Chiyonobu, Hehe Chen, Acacia Clark, Susan DeBari, Raymond Johnston, Ally Peccia, Yuzuru Yamamoto, Alexis Bernard, Tatiana Fernandez Perez, Christopher Jones, Kumar Batuk Joshi, Günther Kletetschka, Xiaohui Li, Antony Morris, Paraskevi Polymenakou, Masako Tominaga, Dimitrios Papanikolaou, Kuo-Lung Wang, Hao-Yang Lee
    Abstract Large explosive volcanic eruptions from island arcs pour pyroclastic currents into marine basins, impacting ecosystems and generating tsunamis that threaten coastal communities and infrastructures. Risk assessments require robust records of such highly hazardous events, which is challenging as most of the products lie buried under the sea. Here we report the discovery by IODP Expedition 398 of a giant rhyolitic pumice deposit emplaced 520 ± 10 ky ago at water depths of 200 to 1000 m during a high-intensity, shallow submarine eruption of ancestral Santorini Volcano. Pyroclastic currents discharged into the sea transformed into turbidity currents and slurries, forming a >89 ± 8 km3 volcaniclastic megaturbidite up to 150 m thick in the surrounding marine basins, while breaching of the sea surface by the eruption column laid down veneers of ignimbrite on three islands. The eruption is one of the largest recorded on the South Aegean Volcanic Arc, and highlights the hazards from submarine explosive eruptions.
    Springer Science and Business Media LLC, Jan. 2024, Communications Earth & Environment, 5(1) (1), English
    [Refereed]
    Scientific journal

  • Nakaoka R., Suzuki K., Kaneko K., Seama N., Kiyosugi K., Yamamoto Y., Matsuno T., Hanyu T., Shimizu S., Tatsumi Y.
    The Volcanological Society of Japan, 2024, PROGRAMME AND ABSTRACTS THE VOLCANOLOGICAL SOCIETY OF JAPAN, 2024, 217 - 217, Japanese

  • Takeru Yoshimoto, Shun Chiyonobu, Yasutomo Omori, Feng Zhang, Yuzuru Yamamoto
    Elsevier BV, Sep. 2023, Tectonophysics, 862, 229922 - 229922, English
    [Refereed]
    Scientific journal

  • Mikito Furuichi, Jian Chen, Daisuke Nishiura, Ryuta Arai, Yuzuru Yamamoto
    Elsevier BV, Sep. 2023, Tectonophysics, 862, 229963 - 229963, English
    [Refereed]
    Scientific journal

  • Stephen A. Bowden, Yuino Kobayashi, Ogheneworo E. Offeh, Man-Yin Tsang, Yuzuru Yamamoto
    Abstract The temperature of maximum pyrolysis yield (known as Tmax) can be used to determine the level of thermal alteration in sedimentary organic matter; higher Tmax values represent higher thermal alteration. Tmax is commonly measured on petroleum source rocks or similar sediments with high organic carbon contents. It would be desirable to measure the Tmax of volcanic sediments because they can have complex patterns of thermal alteration. However, volcanic sediments often have low total organic carbon contents and consequently are susceptible to analytical interferences. Despite this, it can be shown that meaningful Tmax measurements can still be made in sediment with organic carbon contents as low as 0.2% and that interference caused by bitumen or ionizable salts can be mitigated by solvent extraction and rinsing with water. Thus, it is reasonable to use temperature programmed pyrolysis to assess levels of thermal alteration in even low total organic carbon volcanoclastic sediments.
    Cambridge University Press (CUP), Feb. 2023, Experimental Results, 4, English
    [Refereed]
    Scientific journal

  • Man-Yin Tsang, Shin Toyoda, Makiko Tomita, Yuzuru Yamamoto
    Elsevier BV, Aug. 2022, Quaternary Geochronology, 71, 101332 - 101332
    [Refereed]
    Scientific journal

  • T. Hirose, Y. Hamada, W. Tanikawa, N. Kamiya, Y. Yamamoto, T. Tsuji, M. Kinoshita, V. B. Heuer, F. Inagaki, Y. Morono, Y. Kubo
    American Geophysical Union ({AGU}), Jun. 2021, Journal of Geophysical Research: Solid Earth, 126(6) (6)
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Verena B. Heuer, Fumio Inagaki, Yuki Morono, Yusuke Kubo, Arthur J. Spivack, Bernhard Viehweger, Tina Treude, Felix Beulig, Florence Schubotz, Satoshi Tonai, Stephen A. Bowden, Margaret Cramm, Susann Henkel, Takehiro Hirose, Kira Homola, Tatsuhiko Hoshino, Akira Ijiri, Hiroyuki Imachi, Nana Kamiya, Masanori Kaneko, Lorenzo Lagostina, Hayley Manners, Harry-Luke McClelland, Kyle Metcalfe, Natsumi Okutsu, Donald Pan, Maija J. Raudsepp, Justine Sauvage, Man-Yin Tsang, David T. Wang, Emily Whitaker, Yuzuru Yamamoto, Kiho Yang, Lena Maeda, Rishi R. Adhikari, Clemens Glombitza, Yohei Hamada, Jens Kallmeyer, Jenny Wendt, Lars Wörmer, Yasuhiro Yamada, Masataka Kinoshita, Kai-Uwe Hinrichs
    Microorganisms in marine subsurface sediments substantially contribute to global biomass. Sediments warmer than 40°C account for roughly half the marine sediment volume, but the processes mediated by microbial populations in these hard-to-access environments are poorly understood. We investigated microbial life in up to 1.2-kilometer-deep and up to 120°C hot sediments in the Nankai Trough subduction zone. Above 45°C, concentrations of vegetative cells drop two orders of magnitude and endospores become more than 6000 times more abundant than vegetative cells. Methane is biologically produced and oxidized until sediments reach 80° to 85°C. In 100° to 120°C sediments, isotopic evidence and increased cell concentrations demonstrate the activity of acetate-degrading hyperthermophiles. Above 45°C, populated zones alternate with zones up to 192 meters thick where microbes were undetectable.
    American Association for the Advancement of Science (AAAS), Dec. 2020, Science, 370(6521) (6521), 1230 - 1234
    Scientific journal

  • A method for core reorientation based on rock remanent magnetization: application to hemipelagic sedimentary soft rock
    Sugimoto, T, Yamamoto, Y, Yamamoto, Y, Lin, W
    Last, Jun. 2020, Material Transactions, 61, English
    [Refereed]
    Scientific journal

  • Nana Kamiya, Yuzuru Yamamoto, Feng Zhang, Weiren Lin
    Mar. 2020, Island Arc
    [Refereed]
    Scientific journal

  • 岩石残留磁化を用いた掘削コア試料の定方位化：半遠洋性堆積軟岩への適用例
    杉本 達洋, 山本 裕二, 山本 由弦, 林 為人
    Mar. 2020, 材料, 69, 256 - 262, Japanese
    [Refereed]
    Research society

  • Man-Yin Tsang, Stephen A. Bowden, Zhibin Wang, Abdalla Mohammed, Satoshi Tonai, David Muirhead, Kiho Yang, Yuzuru Yamamoto, Nana Kamiya, Natsumi Okutsu, Takehiro Hirose, Myriam Kars, Florence Schubotz, Akira Ijiri, Yasuhiro Yamada, Yusuke Kubo, Yuki Morono, Fumio Inagaki, Verena B. Heuer, Kai-Uwe Hinrichs
    Elsevier {BV}, Feb. 2020, Marine and Petroleum Geology, 112, 104080 - 104080
    [Refereed]
    Scientific journal

  • Ken-ichi Hirauchi, Yuzuru Yamamoto, Sabine A.M. den Hartog, André R. Niemeijer
    Elsevier {BV}, Feb. 2020, Earth and Planetary Science Letters, 531, 115967 - 115967, English
    [Refereed]
    Scientific journal

  • 海洋底の科学掘削
    山本由弦, 木戸ゆかり, 山田泰広
    Dec. 2019, 地盤工学会誌, 67, 42 - 43, Japanese
    [Refereed][Invited]
    Scientific journal

  • Spatial distribution of mass-transport deposits deduced from high-resolution stratigraphy: the Pleistocene forearc basin, central Japan
    Masayuki Utsunomiya, Yuzuru Yamamoto
    Nov. 2019, Geophysical Monograph, 246, 57 - 69, English
    [Refereed]
    Scientific journal

  • Yuki Ota, Junichiro Kuroda, Asuka Yamaguchi, Atsushi Suzuki, Daisuke Araoka, Toyoho Ishimura, Hodaka Kawahata, Y. Hamada, Y. Yamamoto, N. Abe
    May 2019, PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY, 521, 138 - 150, English
    [Refereed]
    Scientific journal

  • A new method for quality control of geological cores by X-ray Computed Tomography and its application in IODP Expedition 370
    Tonai, S., Kubo, Y., Tsang, M.-Y., Bowden, S., Ide, K., Hirose, T., Kamiya, N., Yamamoto, Y., Yang, K., Yamada, Y., Morono, Y., Heuer, V., Inagaki, F., Expedition 370 Scientists
    Mar. 2019, Frontiers in Earth Science, 7, English
    [Refereed]
    Scientific journal

  • Nana Kamiya, Masayuki Utsunomiya, Yuzuru Yamamoto, Junichi Fukuoka, Feng Zhang, Weiren Lin
    Geological Society of London, 2019, Geological Society, London, Special Publications, 477(1) (1), 255 - 264, English
    [Refereed]
    Scientific journal

  • Constrains on the fluid supply rate into and through gas hydrate reservoir systems as inferred from pore-water chloride and in situ temperature profiles, Krishna-Godavari Basin, India
    Kinoshita, M., Ijiri, A., Haraguchi, S., et al.
    Jan. 2019, Marine and Petroleum Geology, 108, 368 - 376, English
    [Refereed]
    Scientific journal

  • Yuki Ota, Hodaka Kawahata, Junichiro Kuroda, Asuka Yamaguchi, Atsushi Suzuki, Daisuke Araoka, Ayako Abe-Ouchi, Yasuhiro Yamada, Akira Ijiri, Toshiya Kanamatsu, Masataka Kinoshita, Kyaw Thu Moe, Weiren Lin, Saneatsu Saito, Yoshinori Sanada, Yohei Hamada, Yasuyuki Nakamura, Yuichi Shinmoto, Hung Yu Wu, Naokazu Ahagon, Kan Aoike, Koichi Iijima, Hideaki Machiyama, Maria Luisa Tejada, Keita Umetsu, Yoichi Usui, Yuzuru Yamamoto, Shuro Yoshikawa, Francisco Jimenez-Espejo, Satoru Haraguchi, Nobuharu Komai, Hisami Suga, Natsue Abe, Lallan Gupta, Takehiro Hirose, Yuka Masaki, Shun Nomura, Takamitsu Sugihara, Wataru Tanikawa, Yusuke Kubo, Lena Maeda, Sean Toczko
    Jan. 2019, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 20(1) (1), 148 - 165, English
    [Refereed]
    Scientific journal

  • Yohei Hamada, Takehiro Hirose, Akira Ijiri, Yasuhiro Yamada, Yoshinori Sanada, Saneatsu Saito, Noriaki Sakurai, Takamitsu Sugihara, Takahiro Yokoyama, Tomokazu Saruhashi, Tatsuhiko Hoshino, Nana Kamiya, Stephen Bowden, Margaret Cramm, Susann Henkel, Kira Homola, Hiroyuki Imachi, Masanori Kaneko, Lorenzo Lagostina, Hayley Manners, Harry-Luke McClelland, Kyle Metcalfe, Natsumi Okutsu, Donald Pan, Maija Jocelyn Raudsepp, Justine Sauvage, Florence Schubotz, Arthur Spivack, Satoshi Tonai, Tina Treude, Man-Yin Tsang, Bernhard Viehweger, David T. Wang, Emily Whitaker, Yuzuru Yamamoto, Kiho Yang, Masataka Kinoshita, Lena Maeda, Yusuke Kubo, Yuki Morono, Fumio Inagaki, Verena B. Heuer
    Nov. 2018, PROGRESS IN EARTH AND PLANETARY SCIENCE, 5, English
    [Refereed]
    Scientific journal

  • Porosity, permeability, and grain size of sediment cores from gas-hydrate-bearing sites and their implication for overpressure in shallow argillaceous formations: Results from the National Gas Hydrate Program Expedition 02, Krishna-Godavari Basin, India
    Tanikawa, W., Hirose, T., Hamada, Y., et al.
    Nov. 2018, Marine and Petroleum Geology, 108, 332 - 347, English
    [Refereed]
    Scientific journal

  • Hirokazu Masumoto, Jun Kameda, Hiroshi Arima, Kazumasa Sugiyama, Takaya Nagai, Yuzuru Yamamoto
    Sep. 2018, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 19(9) (9), 2991 - 3003, English
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Kameda Jun, Fukuyama Mayuko, Yamaguchi Haruka
    2018, Geological Society of America, Special Papers, 534, 115 - 127, English
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Chiyonobu Shun, Kanamatsu Toshiya, Ahagon Naokazu, Aoike Kan, Kamiya Nana, Ojima Takanori, Hirose Takehiro, Sugihara Terumitsu, Saito Saneatsu, Kinoshita Masataka, Kubo Yusuke, Yamada Yasuhiro, NGH, Scientist
    AbstractThe National Gas Hydrate Program Expedition 02 was conducted in early 2015 using the Drilling Vessel Chikyu in the western part of the Bay of Bengal, India. During drilling off Vishakhapatnam, NE India, some bottom-simulating reflectors were penetrated, and numerous mass-transport deposits (MTDs) were identified. The recovered cores were composed of post-late Miocene muddy slope deposits containing the late Miocene–Pliocene hiatus that is widespread in that region. Based on detailed visual core descriptions and calcareous nannofossil biostratigraphy, two major MTD-rich intervals were identified: the Pleistocene interval above the hiatus, and the middle–late Miocene interval below it. Although the MTDs in both intervals are composed of variously coloured clay–silt blocks in an olive-black or olive-grey silty clay matrix (muddy MTDs), the Pleistocene MTDs consist of larger-sized blocks (mostly less than a few metres but with some >10 m) without clear shear fabrics, whereas the Miocene MTDs contain smaller blocks (<0.1 m) with asymmetrical shear fabrics. The muddy blocks are composed of older components (Pliocene–Cretaceous) compared with the depositional ages of the MTDs. The high abundance of MTDs above the hiatus and the depositional ages of the interbedded coherent layers indicate that large-scale MTDs occurred repeatedly during the Pleistocene. Such repeated MTDs contributed to maintaining the high sedimentation rate in this area and potentially provided stable pressure and temperature conditions for the formation of gas hydrates.
    Geological Society of London, 2018, Geological Society, London, Special Publications, 477(1) (1), 183 - 193, English
    [Refereed]
    Scientific journal

  • Nomura Shun, Yamamoto Yuzuru, Sakaguchi Hide
    2018, Soils and Foundations, 58(6) (6), 1350 - 1357, English
    [Refereed]
    Scientific journal

  • Nomura Shun, Hitomi Junpei, Cesare Giovanni D, Takeda Yasushi, Yamamoto Yuzuru, Sakaguchi Hide
    2018, Geological Society, London, Special Publications, 477(1) (1), 427 - 437, English
    [Refereed]
    Scientific journal

  • Recovery of in-situ orientation of drilled rock core samples for crustal stress measurements, in Litvinenko (Ed.)
    Sugimoto, T, Yamamoto, Y, Lin, W, Yamamoto, Y, Hirose, T, Kamiya, N
    2018, Geomechanics and Geodynamics of Rock Masses (Proceedings of European Rock Mechanics Symposium 2018), 1, 563 - 566, English
    International conference proceedings

  • Hitomi Uchimura, Hiroshi Nishi, Reishi Takashima, Azumi Kuroyanagi, Yuzuru Yamamoto, Steffen Kutterolf
    Oct. 2017, PALEONTOLOGICAL RESEARCH, 21(4) (4), 380 - 396, English
    [Refereed]
    Scientific journal

  • Rina Fukuchi, Asuka Yamaguchi, Yuzuru Yamamoto, Juichiro Ashi
    Aug. 2017, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 18(8) (8), 3185 - 3196, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Yohei Hamada, Nana Kamiya, Takanori Ojima, Shun Chiyonobu, Saneatsu Saito
    Jul. 2017, TECTONOPHYSICS, 710, 81 - 87, English
    [Refereed]
    Scientific journal

  • Shun Chiyonobu, Yuzuru Yamamoto, Saneatsu Saito
    Jul. 2017, TECTONOPHYSICS, 710, 56 - 68, English
    [Refereed]
    Scientific journal

  • Nana Kamiya, Yuzuru Yamamoto, Qian Wang, Yuhei Kurimoto, Feng Zhang, Takato Takemura
    Jul. 2017, TECTONOPHYSICS, 710, 69 - 80, English
    [Refereed]
    Scientific journal

  • 山本由弦, 千代延俊, 神谷奈々, 濱田洋平, 斎藤実篤
    日本地質学会, 2017, 地質学雑誌, 123(1) (1), 41 - 55, Japanese
    [Refereed]
    Scientific journal

  • Weiren Lin, Timothy B. Byrne, Masataka Kinoshita, Lisa C. McNeill, Chandong Chang, Jonathan C. Lewis, Yuzuru Yamamoto, Demian M. Saffer, J. Casey Moore, Hung-Yu Wu, Takeshi Tsuji, Yasuhiro Yamada, Marianne Conin, Saneatsu Saito, Takatoshi Ito, Harold J. Tobin, Gaku Kimura, Kyuichi Kanagawa, Juichiro Ashi, Michael B. Underwood, Toshiya Kanamatsu
    Dec. 2016, TECTONOPHYSICS, 692, 120 - 130, English
    [Refereed]
    Scientific journal

  • KURIMOTO Yuhei, YAMAMOTO Yuzuru, SAKAGUCHI Hide, SAEDA Yukimasa, ZHANG Feng
    Initiation of décollement zone in incoming sediments is crucial important to understand the mechanism of plate boundary faulting subduction zones and consequently it may help to clarify the formation mechanism of seismogenic zone. The basic mechanism of the décollement zone, e.g., the macro-micro behaviors during the initiation and the evolution of the plate boundary, however, remain poorly understood. In this paper, the influence of shear deformation happened in the process of oceanic plate subduction beneath continental plate, and the dynamic force-propagation due to earthquake on the formation of the décollement zone are investigated by means of specific numerical tests. Particular attention is paid to the change of volumetric strain of the geomaterials in the proto-décollement zone. Significant compressive volumetric strain was identified when the material has subjected to periodic earthquake loadings during 1000 years with a re-occurring period of every 200 years. Amazingly, in spite of the fact that more than 5% of the volumetric strain, the structure of the material within the proto-décollement zone remains undisturbed, which is quite similar to the micro-structural characteristics of décollement zone (high density and random fabric). In other words, the repeated dynamic load due to earthquake is apparently the main mechanism to form the décollement zone.
    The Japanese Geotechnical Society, 2016, Japanese Geotechnical Journal, 11(4) (4), 353 - 363, Japanese
    [Refereed]
    Scientific journal

  • KURIMOTO Yuhei, YAMAMOTO Yuzuru, SKAGUCHI Hide, SAEDA Yukimasa, ZHANG Feng
    Initiation of d?collement zone in incoming sediments is crucial important to understand the mechanism of plate boundary faulting in subduction zones and consequently it may help to clarify the nature of seismogenic zone. However, the basic mechanism and dynamics during the initiation and the evolution of the plate boundary d?collement zone remain poorly understood. It is therefore assumed that cyclic loading both in isotropic and deviatory stress due to stress wave propagation, especially P-wave during an earthquake, might cause a dramatic change in fabric and physical properties of sediments. In this paper, semi-lithified trench-slope siltstone from the Boso Peninsula and Fujinomori clay are tested with static and dynamic load under high confining pressure. Meanwhile, anisotropy of magnetic susceptibility (AMS) is also measured to check the changes in the internal textures of the specimen after these tests. As the results, no major fabric variation was confirmed based on AMS, in spite of substantial residual deformation occurred due to cyclic loading. These results are exactly the same as the mechanical properties of d?collement zone in which the internal texture remained unchanged but the density increased significantly.
    The Japanese Geotechnical Society, 2016, Japanese Geotechnical Journal, 11(4) (4), 341 - 351, Japanese
    [Refereed]
    Scientific journal

  • Starting material for the ancient earthquake rupture in shallow portion of subduction zone: Ishido thrust (OST) in Boso Peninsula, central Japan
    Yamamoto,Yuzuru, Fukuyama,Mayuko, Chiyonobu,Shun, Ujiie,Kohtaro, Hamada,Yohei, Kamiya,Nana
    The Geological Society of Japan, 2016, Annual Meeting of the Geological Society of Japan, 2016(0) (0), 256, Japanese
    Symposium

  • Yu Saitoh, Tsuyoshi Ishikawa, Masaharu Tanimizu, Masafumi Murayama, Yurika Ujiie, Yuzuru Yamamoto, Kohtaro Ujiie, Toshiya Kanamatsu
    Jul. 2015, EARTH AND PLANETARY SCIENCE LETTERS, 421, 47 - 57, English
    [Refereed]
    Scientific journal

  • Yuhei Kurimoto, Yuzuru Yamamoto, Hide Sakaguchi, Feng Zhang, Yukimasa Saeda
    Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, 2015, 15th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2015: New Innovations and Sustainability, 12, 498 - 503, English
    [Refereed]
    International conference proceedings

  • Fukuchi Rina, Yamaguchi Asuka, Yamamoto Yuzuru, Ashi Juichiro
    The Geological Society of Japan, 2015, Annual Meeting of the Geological Society of Japan, 2015, 538

  • Kamiya Nana, Yamamoto Yuzuru, Takemura Takato
    The Geological Society of Japan, 2015, Annual Meeting of the Geological Society of Japan, 2015, 238 - 238

  • Leslie Gadenne, Hugues Raimbourg, Remi Champallier, Yuzuru Yamamoto
    Dec. 2014, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 15(12) (12), 5001 - 5014, English
    [Refereed]
    Scientific journal

  • Kai Schumann, Jan H. Behrmann, Michael Stipp, Yuzuru Yamamoto, Yujin Kitamura, Christof Lempp
    Oct. 2014, EARTH PLANETS AND SPACE, 66, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto
    Oct. 2014, MARINE GEOLOGY, 356, 65 - 70, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Shunsuke Kawakami
    Lead, 2014, Advances in Natural and Technological Hazards Research Series, 37, 551 - 560, English
    [Refereed]
    International conference proceedings

  • 世界遺産の島・屋久島の地質と成り立ち
    安間了, 山本由弦, 下司信夫, 七山太, 中川正二郎
    2014, 地質学雑誌補遺, 120, 101 - 125, English
    [Refereed]
    Scientific journal

  • R.N. Harris, A. Sakaguchi, K. Petronotis, A.T. Baxter, R. Berg, A. Burkett, D. Charpentier, J. Choi, P. Diz Ferreiro, M. Hamahashi, Y. Hashimoto, K. Heydolph, L. Jovane, M. Kastner, W. Kurz, S.O. Kutterolf, Y. Li, A. Malinverno, K.M. Martin, C. Millan, D.B. Nascimento, S. Saito, M.I. Sandoval Gutierrez, E.J. Screaton, C.E. Smith-Duque, E.A. Solomon, S.M. Straub, W. Tanikawa, M.E. Torres, H. Uchimura, P. Vannucchi, Y. Yamamoto, Q. Yan, X. Zhao
    Integrated Ocean Drilling Program, Dec. 2013, Proceedings of the Integrated Ocean Drilling Program, English, International magazine, Co-authored internationally
    [Refereed]
    In book

  • Paola Vannucchi, Peter B. Sak, Jason P. Morgan, Ken'ichi Ohkushi, Kohtaro Ujiie
    Sep. 2013, GEOLOGY, 41(9) (9), 995 - 998, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Weiren Lin, Hirokuni Oda, Timothy Byrne, Yuhji Yamamoto
    Jul. 2013, Tectonophysics, 600, 91 - 98, English
    [Refereed]
    Scientific journal

  • Jun Kameda, Yuzuru Yamamoto, Yohei Hamada, Koichiro Fujimoto, Gaku Kimura
    Jul. 2013, TECTONOPHYSICS, 600, 41 - 51, English
    [Refereed]
    Scientific journal

  • Robert N. Harris, Expedition 344 Scientists, Arito Sakaguchi, Katerina Petronotis, Alberto Malinverno, Alan T. Baxter, Richard Berg, Ashley Burkett, Delphine Charpentier, Jiyoung Choi, Paula Diz Ferreiro, Mari Hamahashi, Yoshitaka Hashimoto, Ken Heydolph, Luigi Jovane, Miriam Kastner, Walter Kurz, Steffen O. Kutterolf, Yongxiang Li, Kylara M. Martin, Cristina Millan, Débora B. Nascimento, Saneatsu Saito, Maria I. Sandoval Gutierrez, Elizabeth J. Screaton, Christopher E. Smith-Duque, Evan A. Solomon, Susanne M. Straub, Wataru Tanikawa, Marta E. Torres, Hitomi Uchimura, Paola Vannucchi, Yuzuru Yamamoto, Quanshu Yan, Xixi Zhao, Thanos Fatouros, Dena Rosenberger
    IODP-MI, Feb. 2013, Integrated Ocean Drilling Program: Preliminary Reports, (344) (344), 1 - 81, English
    [Refereed]
    Scientific journal

  • Xixi Zhao, Hirokuni Oda, Huaichun Wu, Tomohiro Yamamoto, Yuhji Yamamoto, Yuzuru Yamamoto, Takeshi Nakajima, Yujin Kitamura, Toshiya Kanamatsu
    2013, Geological Society Special Publication, 373(1) (1), 191 - 243, English
    [Refereed]
    Scientific journal

  • Paola Vannucchi, Kohtaro Ujiie, Nicole Stroncik, Alberto Malinverno, Ivonne Arroyo, Udo Barckhausen, Marianne J. Conin, Susan Murr Foley, Michael J. Formolo, Robert N. Harris, Arnauld Heuret, Gary J Huftile, Jun Kameda, Gil Young Kim, Steffen O. Kutterolf, Amanda J. Martino, Gillian A. McCay, Marianne Nuzzo, Ken'ichi Ohkushi, Saneatsu Saito, Peter B. Sak, Evan A. Solomon, Michael Stipp, Marta E. Torres, Akito Tsutsumi, Masaoki Uno, Yoichi Usui, Yatheesh Vadakkeyakath, Yuzuru Yamamoto, Xixi Zhao, Junjiang Zhu, Jenifer Saltman
    2013, Scientific Drilling, 15(15) (15), 23 - 30, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Shun Chiyonobu, Toshiyuki Kurihara, Asuka Yamaguchi, Shoko Hina, Mari Hamahashi, Hugues Raimbourg, Romain Augier, Leslie Gadenne
    Dec. 2012, ISLAND ARC, 21(4) (4), 231 - 234, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Kazuki Tonogai, Ryo Anma
    Sep. 2012, TECTONOPHYSICS, 568, 65 - 73, English
    [Refereed]
    Scientific journal

  • Tetsuya Tokiwa, Yuzuru Yamamoto
    Sep. 2012, TECTONOPHYSICS, 568, 53 - 64, English
    [Refereed]
    Scientific journal

  • Jun Kameda, Shoko Hina, Kyoko Kobayashi, Asuka Yamaguchi, Yohei Hamada, Yuzuru Yamamoto, Mari Hamahashi, Gaku Kimura
    Feb. 2012, EARTH AND PLANETARY SCIENCE LETTERS, 317, 136 - 144, English
    [Refereed]
    Scientific journal

  • Yuzuru Yamamoto, Derek E. Sawyer
    2012, SUBMARINE MASS MOVEMENTS AND THEIR CONSEQUENCES, 31, 649 - +, English
    [Refereed]
    International conference proceedings

  • Yuzuru Yamamoto, Yasuhiro Yamada, Yoshihiko Yamashita, Shun Chiyonobu, Tadahiro Shibata, Megumi Hojo
    2012, SUBMARINE MASS MOVEMENTS AND THEIR CONSEQUENCES, 31, 355 - +, English
    [Refereed]
    International conference proceedings

  • Yujin Kitamura, Yuzuru Yamamoto
    2012, SUBMARINE MASS MOVEMENTS AND THEIR CONSEQUENCES, 31, 659 - +, English
    [Refereed]
    International conference proceedings

  • Taira Asahiko, Iijima Koichi, Igarashi Chiaki, Sakai Saburo, Sakaguchi Hide, Sakaguchi Arito, Kikawa Eiichi, Kanamatsu Toshiya, Yamamoto Yuzuru, Azuma Wataru, Tanaka Tomoyuki, Nishimura Masahiro, Suzuki Takahiro, Kido Yoshiki, Watanabe Naoto, Okuno Minoru, Inoue Takeshi, Mayuzumi Hiroshi, Oda Tomoya, Hamada Taiji, Muroyama Takuo, Takao Ino, Takashina Jitsuo, Katsumata Hidenobu, Harada Naoshi, Fumiaki Nishida, Minamikawa Hiroyuki, Kanetaka Yoshinao
    The 2011 off the Pacfic coast of Tohoku Earthquake caused an unprecedented and widespread soil liquefaction event especially in the southern part of the Kanto district. An improved understanding of the complex liquefaction processes involved and especially identification of the liquefaction layer, is needed to understand and mitigate against such events. We report here for the first time the application of X-ray computerized tomography (CT) scanning to core samples of the soft and water-saturated near-surface formations subjected to liquefaction. Our results clearly show images of the different sedimentary units and their internal structure, including ripple laminations and load casts. One unit was identified where the original sedimentary structures have been completely obliterated, which we interpret to be the zone of liquefaction. Our results show that X-ray CT scanning is a potentially useful tool for soil liquefaction research in the fields of geology and engineering.
    The Geological Society of Japan, 2012, Jour. Geol. Soc. Japan, 118(7) (7), 410 - 418, Japanese
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Lin Weiren, Usui Yoichi, Kanamatsu Toshiya, Saito Saneatsu, Zhao Xixi, Ujiie Kohtaro, Paola Vannucchi, Expedition 334 Scientists
    The Geological Society of Japan, 2012, Annual Meeting of the Geological Society of Japan, 2012, 77 - 77

  • Kitamura Yujin, Kanamatsu Toshiya, Yamamoto Yuzuru, Kawamura Kiichiro, Novak Beth, Oda Hirokuni, Wu Huaichun, Yamamoto Tomohiro, Zhao Xixi
    The Geological Society of Japan, 2012, Annual Meeting of the Geological Society of Japan, 2012, 66 - 66

  • Weiren Lin, Saneatsu Saito, Yoshinori Sanada, Yuzuru Yamamoto, Yoshitaka Hashimoto, Toshiya Kanamatsu
    Oct. 2011, GEOPHYSICAL RESEARCH LETTERS, 38, English
    [Refereed]
    Scientific journal

  • Weiren Lin, Saneatsu Saito, Yoshinori Sanada, Yuzuru Yamamoto, Yoshitaka Hashimoto, Toshiya Kanamatsu
    Sep. 2011, GEOPHYSICAL RESEARCH LETTERS, 38, English
    [Refereed]
    Scientific journal

  • TSUCHIDA Kunihiro, SHIMODA Naoyuki, YAMAMOTO Yuzuru, SATO Ryuichi, TSUJI Yoshihiro, VILLALON Rodrigo Maldonado, TOVAR Enrique Reyes, CESPEDES Hector Lopez, GONZALEZ Jose Vicente Ortega, BORBOLLA Gerardo Basurto
    石油技術協会, 2011, Journal of the Japanese Association for Petroleum Technology, 76(1) (1), 70 - 76, Japanese
    [Refereed]
    Scientific journal

  • Jun Kameda, Yuzuru Yamamoto, Gaku Kimura
    Oct. 2010, TECTONOPHYSICS, 494(1-2) (1-2), 75 - 84, English
    [Refereed]
    Scientific journal

  • Michael B. Underwood, Saneatsu Saito, Yu'suke Kubo, Y. Sanada, S. Chiyonobu, C. Destrigneville, B. Dugan, P. Govil, Y. Hamada, V. Heuer, A. Hupers, M. Ikari, Y. Kitamura, S. Kutterolf, S. Labanieh, J. Moreau, H. Naruse, H. Oda, J. O. Park, K. Pickering, R. Scudder, A. Slagle, G. Spinelli, M. Torres, J. Tudge, H. Wu, T. Yamamoto, Y. Yamamoto, X. Zhao
    Copernicus GmbH, Sep. 2010, Scientific Drilling, 10(10) (10), 14 - 25, English
    [Refereed]
    Scientific journal

  • Yasuhiro Yamada, Yoshihiko Yamashita, Yuzuru Yamamoto
    Mar. 2010, TECTONOPHYSICS, 484(1-4) (1-4), 156 - 167, English
    [Refereed]
    Scientific journal

  • Applications of anelastic strain measurements in scientific ocean deep drillings
    Weiren Lin, Timothy B. Byrne, Akito Tsutsumi, Yuhji Yamamoto, Arito Sakaguchi, Yuzuru Yamamoto, Chandong Chang
    2010, ROCK STRESS AND EARTHQUAKES, 199 - 204, English
    [Refereed]
    International conference proceedings

  • A comparison of stress orientations determined by two independent methods in a deep drilling project
    W. Lin, T. Byrne, A. Tsutsumi, C. Chang, Y. Yamamoto, A. Sakaguchi
    2010, ROCK MECHANICS IN CIVIL AND ENVIRONMENTAL ENGINEERING, 749 - 752, English
    International conference proceedings

  • Yuzuru Yamamoto, Manami Nidaira, Yasufumi Ohta, Yujiro Ogawa
    Sep. 2009, ISLAND ARC, 18(3) (3), 496 - 512, English
    [Refereed]
    Scientific journal

  • P. B. Fleming, H. Long, B. Dugan, J. Germaine, C. John, J. H. Behrmann, D. Sawyer
    May 2008, EARTH AND PLANETARY SCIENCE LETTERS, 269(3-4) (3-4), 309 - 324, English
    [Refereed]
    Scientific journal

  • Submarine Landslides at Submarine Margins: Insights from Physical Models
    Yamada Yasuhiro, Yamashita Yoshihiko, Yamamoto Yuzuru, Matsuoka Toshifumi
    2008, Bollettino di Geofisica teorica ed applicata, 49, 198 - 203, English
    [Refereed]
    Scientific journal

  • Shibata Tadahiro, Orihashi Yuji, Yamamoto Yuzuru, Kinoshita Masataka
    The Geological Society of Japan, 2008, Annual Meeting of the Geological Society of Japan, 2008, 203 - 203, Japanese

  • Yuzuru Yamamoto, Yujiro Ogawa, Takayuki Uchino, Satoru Muraoka, Tae Chiba
    Dec. 2007, ISLAND ARC, 16(4) (4), 505 - 507, English
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Kurihara Toshiyuki, Tokiwa Tetsuya, Ueda Hayato, Nakae Satoshi, Wakita Koji, Hara Hidetoshi, Uchino Takayuki, Ueno Hikaru, Kamata Yoshihito, Yamada Yasuhiro, Miyakawa Ayumu, Tsuji Takeshi
    The Geological Society of Japan, 2007, Journal of the Geological Society of Japan, 113(11) (11), XVII - XVIII, Japanese
    [Refereed]
    Scientific journal

  • Y Yamamoto
    Apr. 2006, EARTH AND PLANETARY SCIENCE LETTERS, 244(1-2) (1-2), 270 - 284, English
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Anma Ryo
    The Geological Society of Japan, 2006, Journal of the Geological Society of Japan, 112(9) (9), XVII - XVIII, Japanese
    [Refereed]
    Scientific journal

  • Behrmann Jan H, Flemings Peter B, John Cedric M, the Expeditio, Scientists
    2006, Scientific Drilling, 3, 12 - 17, English
    [Refereed]
    Scientific journal

  • Y Yamamoto, H Mukoyoshi, Y Ogawa
    Oct. 2005, TECTONICS, 24(5) (5), English
    [Refereed]
    Scientific journal

  • Y Yamamoto, S Kawakami
    Jun. 2005, ISLAND ARC, 14(2) (2), 178 - 198, English
    [Refereed]
    Scientific journal

  • 三浦半島南部の三浦層群三崎層の地質構造とテクトニクス
    小川勇二郎, 山本由弦, 仁平麻奈美
    2003, 日本地質学会第110年大会見学旅行案内書, 143 - 162, Japanese
    [Refereed]
    Scientific journal

  • HIRONO Tetsuro, YOKOYAMA Tadashi, TAKAHASHI Manabu, NAKASHIMA Satoru, YAMAMOTO Yuzuru, LIN Weiren
    The Geological Society of Japan, Sep. 2002, The Journal of the Geological Society of Japan, 108(9) (9), 606 - 609, Japanese
    [Refereed]
    Scientific journal

  • YAMAMOTO,Yuzuru, ANMA,Ryo
    The Geological Society of Japan, Sep. 2002, 日本地質学会学術大会講演要旨, 109, 127 - 127, Japanese
    Scientific journal

  • TAKAHASHI Manabu, LIN Weiren, HIRONO Tetsuro, YAMAMOTO Yuzuru
    To visualize the microstructure in rocks, micro focus X ray CT images that can get three-dimensional data simultaneously with high resolution of 10 micron have been introduced. We obtained multi planar reconstruction images in intact Berea sandstone and Shirahama sandstone. In the intact rocks, pore structures and grain boundaries are distinguished well. Furthermore, existence of the crushed grains arrangements and fracture band is confirmed definitely in the compressed Berea sandstone under confining pressure of 12 MPa. Micro focus X ray CT is rather effective in visualizing the microstructures in rocks.
    Japan Society of Engineering Geology, 2002, Journal of the Japan Society of Engineering Geology, 43(4) (4), 235 - 238, Japanese
    [Refereed]
    Scientific journal

  • Structural profile of the Nankai accretionary prism and Calyptogena colonies along the Shionomisaki submarine canyon: results of "SHINKAI" 6K#522 and #579 dives.
    Ryo Anma
    JAMSTEC, Jan. 2002, JAMSTEC J. Deep Sea Res., 20, 59-75 - 75, Japanese
    Scientific journal

  • Y Yamamoto, Y Ohta, Y Ogawa
    Oct. 2000, TECTONOPHYSICS, 325(1-2) (1-2), 133 - 144, English
    [Refereed]
    Scientific journal

  • 三浦半島南端の三崎層に見られるデュープレックス構造
    山本由弦, 大田恭史, 小川勇二郎
    1998, 地質学雑誌, 104, XVII - XVIII, Japanese
    [Refereed]
    Scientific journal

  • Yamamoto Yuzuru, Ogawa Yujiro, Ohta Yasufumi
    The Geological Society of Japan, 1998, Annual Meeting of the Geological Society of Japan, 1998, 255 - 255, Japanese

■ MISC
  • Pore structure change by nanoscale particle fracturing in the fault gouge of the Shirako fault in the Miura-Boso accretionary prism
    中元啓輔, 亀田純, 濱田洋平, 山本由弦
    May 2023, 日本地球惑星科学連合大会予稿集(Web), 2023

  • Late Pleistocene to Holocene dynamic basin environment at the Osaka Bay: Stratigraphic expressions of tectonic deformation, sea level fluctuation, and tidal waves
    HAMAHASHI Mari, OTSUKA Hironori, SUZUKI Yoshiaki, ARIMOTO Jun, YAMAMOTO Yuzuru, YAMAMOTO Yuzuru, SEAMA Nobukazu, SEAMA Nobukazu, BOWDEN Stephen, BOWDEN Stephen, MATSUNO Tetsuo, SUGIOKA Hiroko, SUGIOKA Hiroko, SHIMIZU Satoshi, SHIMIZU Satoshi, IWAMARU Hikaru, IWAMARU Hikaru, SANO Mamoru, SANO Mamoru, SUZUKI Keita, SUZUKI Keita, KANEKO Katsuya, KANEKO Katsuya, NAKAHIGASHI Kazuo, TATSUMI Yoshiyuki
    2022, 日本地球惑星科学連合大会予稿集(Web), 2022

  • Hanyu Takeshi, Chang Q., Kaneko Katsuya, Nakaoka Reina, Kiyosugi Koji, Suzuki―Kamata Keiko, Yamamoto Yuzuru, Matsuno Tetsuo, Seama Nobukazu, Tatsumi Yoshiyuki
    Kikai submarine caldera caused several catastrophic eruptions. In order to understand the eruption processes and magmatic evolution, we measured chemical composition of tephra collected via the SCORE program with D/V Chikyu. We used submarine tephra from the K-Ah eruption (7300 years ago), that from the K-Tz eruption (95000 years ago), and that intercalated between the two catastrophic eruptions, the age of which is approximately 40000 years ago or younger. The tephra from the K-Tz eruption is predominated by felsic pyroclasts, but the presence of a few mafic pyroclasts suggests the contribution of mafic melts during the K-Tz eruption. The tephra intercalated between the two catastrophic eruptions have chemical composition similar to those of K-Ah, implying that the storage of felsic magmas commenced at least 40000 years ago toward the next catastrophic eruption of K-Ah.
    GEOCHEMICAL SOCIETY OF JAPAN, 2022, Abstracts of Annual Meeting of the Geochemical Society of Japan, 69, 96, Japanese

  • Nakaoka Reina, Kaneko Katsuya, Seama Nobukazu, Suzuki Keiko, Kiyosugi Koji, Hanyu Takeshi, Yamamoto Yuzuru, Matsuno Tetsuo, Satoshi Shimizu, Sugioka Hiroko, Yoshiyuki Tatsumi
    Kikai Caldera volcano has repeatedly erupted in large scale eruptions such as the Kikai Akahoya eruption 7,300 years ago and the Kikai Tozurahara eruption 95,000 years ago, and detailed eruption history can be studied by combining seafloor and on-land surveys.In this study, core samples were collected by the SCORE program of CHIKYU based on the subsurface structure revealed by seismic reflection surveys of large eruptive ejecta on the seafloor, which are still largely unknown.The chemical composition of the volcanic glass was analyzed and compared with subaerial deposits, and it was found that the two large-scale eruptive ejecta are thickly deposited on the seafloor as well, and that the Kikai Akahoya product is divided into two units on the seafloor as well.In addition, the chemical compositional characteristics of volcanic glass in piston core samples from a wide area around the Kikai caldera suggest that the Kikai Akahoya product may have become less accessible to distant sites as the eruption progressed.
    GEOCHEMICAL SOCIETY OF JAPAN, 2022, Abstracts of Annual Meeting of the Geochemical Society of Japan, 69, 95, Japanese

  • 国際深海科学掘削計画第352次研究航海で掘削された前弧玄武岩とボニナイトの物性研究
    本多睦美, 道林克禎, 山本由弦, 神谷奈々, 渡辺了, 柵山徹也
    2016, 日本地球惑星科学連合大会予稿集(Web), 2016

  • Yamamoto,Yuzuru, Chiyonobu,Shun, Ujiie,Kohtaro, Hamada,Yohei, Kamiya,Nana, Saito,Saneatsu
    The Geological Society of Japan, 2015, Annual Meeting of the Geological Society of Japan, 2015(0) (0), 237 - 237, Japanese

■ Lectures, oral presentations, etc.
  • 泥質岩の最高被熱温度とスメクタイト含有量の関係性
    関山 優希, 山本 由弦, 上間 綾乃, 石田良二, 望月一磨, 上野 光
    日本応用地質学会研究発表会, Oct. 2024, Japanese
    Poster presentation

  • 最高被熱温度による山岳トンネルの地山評価の可能 性について
    望月 一磨, 今井 啓文, 石川 太郎, 関山 優希, 山本 由弦, 西金 佑一郎, 浦越 拓野, 上野 光
    日本応用地質学会研究発表会, Oct. 2024, Japanese
    Oral presentation

  • 堆積物の内部変形構造解析における三次元デジタル露頭モデル 構築の手法-富山県上市町稲村に分布する下部中新統折戸凝灰 岩部層の例-
    荒戸裕之, 金子一夫, 國香正稔, 山本由弦, 保柳康一, 山田泰広, 白石和也, 千代延俊, 藤田将人, 吉本剛瑠, 関山優希
    日本地質学会第131年学術大会, Sep. 2024, Japanese
    Poster presentation

  • 富山県上市町の下部中新統稲村水中地すべり堆積物の内部変形 構造から推定される滑動メカニズム
    荒戸裕之, 山本由弦, 保柳康一, 金子一夫, 國香正稔, 山田泰広, 白石和也, 千代延俊, 藤田将人, 吉本剛瑠, 関山優希
    日本地質学会第131年学術大会, Sep. 2024, Japanese
    Oral presentation

  • 海嶺沈み込みに起因する前弧海盆の局所的な変形構造〜新第三系宮崎層群〜
    吉本 剛瑠, 山本 由弦
    JpGU 2024, May 2024, Japanese
    Oral presentation

  • Results from IODP Expedition 398: Giant offshore pumice deposit records a shallow submarine explosive eruption of ancestral Santorini
    Tim Drui, Steffen Kutterolf, Thomas A. Ronge, Christian Hübscher, Paraskevi Nomikou, Jonas Preine, Ralf Gertisser, Jens Karstens, Jörg Keller, Olga Koukousioura, Michael Manga, Abigail Metcalfe, Molly McCanta, Iona McIntosh, Katharina Pank, Adam Woodhouse, Sarah Beethe, Carole Berthod, Shun Chiyonobu, Hehe Chen, Acacia Clark, Susan DeBari, Raymond Johnston, Ally Peccia, Yuzuru Yamamoto, Alexis Bernard, Tatiana Fernandez Perez, Christopher Jones, Kumar Batuk Joshi, Günther Kletetschka, Xiaohui Li, Antony Morris, Paraskevi Polymenakou, Masako Tominaga, Dimitrios Papanikolaou, Kuo-Lung Wang, Hao-Yang Lee
    JpGU2024, May 2024, English
    Oral presentation

  • Granular simulation for earthquakes in geological scale structure evolution
    Mikito Furuichi, Jian Chen, Daisuke Nishiura, Ryuta Arai, Yuzuru Yamamoto, Satoshi Ide
    JpGU2024, May 2024, English
    Oral presentation

  • Consolidation characteristics of offshore sediments in the Christiana, Santorini, and Kolumbo volcanic field, Greece (IODP Expedition 398)
    吉本 剛瑠, 山本 由弦, Manga Michael, Beethe Sarah, McIntosh Iona, Woodhouse Adam, 千代延 俊, Koukousioura Olga, Druitt Tim, Kutterolf Steffen, Ronge Thomas, IODP Ex, Scientists
    JpGU2024, May 2024, Japanese
    Poster presentation

  • The frictional properties of an imbricate thrust of the Miura accretionary complex for a wide range of slip velocities
    Yuki Kasai, Akito Tsutsumi, Yuzuru Yamamoto, Horst Zwingmann, Andrew Todd
    JpGU2024, May 2024, English
    Poster presentation

  • Fluidization of a fault in a shallow portion of an accretionary prism during faulting
    Akito Tsutsumi, Keigo Tashiro, Kasai Yuki, Chengrui Chang, Chao Huang, Gonghui Wang, Yuzuru Yamamoto
    JpGU2024, May 2024, English
    Oral presentation

  • Consolidation characteristics of offshore sediments in the Christiana, Santorini, and Kolumbo volcanic field, Greece (IODP Expedition 398)
    Takeru Yoshimoto, Michael Manga, Sarah Beethe, Iona McIntosh, Adam Woodhouse, Shun Chiyonobu, Olga Koukousioura, Timothy Druitt, Steffen Kutterolf, and Thomas Ronge and the IODP Exp. 398 Scientists
    EGU General Assembly 2024, Apr. 2024, English
    Poster presentation

  • IODP Expedition 398 Reveals a Major Normal Fault along the Kolumbo Volcanic Chain
    Jonas Preine, Christian Hübscher, Abigail Metcalfe, Katharina Pank, Adam Woodhouse, Olga Koukousioura, Shun Chiyonobu, Timothy Drui, Steffen Kutterolf, Paraskevi Nomikou, Thomas Ronge, Sarah Beehte, Miachel Manga, Iona McInsoth, Masako Tominga, Gareth Crutchley, Jens Karstens, he IODP Expeditio, Scientists
    EGU General Assembly 2024, Apr. 2024, English
    Oral presentation

  • A sequence of volcanic events from sediment cores IODP398, U1589, near Santorini
    Gunther Kletetschka, Anthony Morris, Alexander Roth, Jonas Preine, Timothy H Drui, Steffen Kutterolf, Thomas Ronge, Christian Huebscher, Shun Chiyonobu, Olga Koukousioura, Yuzuru Yamamoto, Adam Woodhouse, Acacia Clark, Susan M DeBari, Sarah Beethe, Carole Bertho, Alexis Bernar, Hehe Chen, Ralf Gertisser, Tatiana I. Fernandez Perez, Christopher Jones, Raymond M. Johnsto, Kumar Batuk Joshi, Li Xiaohui, Michael Manga, Molly C McCanta, Iona M McIntosh, Katharina Pank, Ally Peccia, Masako Tominaga, Paraskevi Nomikou, Paraskevi Polymenakou, Sara E. Whitlock, Susan Schnur
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Scientific Ocean Drilling in a Volcanic Field – The Good, the Bad, and the Ugly
    Thomas Ronge, Timothy Drui, Steffen Kutterolf, Sarah Beethe, Alexis Bernard, Carole Berthod, Hehe Chen, Shun Chiyonobu, Acacia Clark, Susan M DeBari, Tatiana I. Fernandez Perez, Ralf Gertisser, Christian Huebsche, Raymond M. Johnsto, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Olga Koukousioura, Li Xiaohui, Michael Manga, Molly C McCanta, Iona M McIntosh, Antony Morris, Paraskevi Nomikou, Katharina Pank, Ally Peccia, Paraskevi Polymenakou, Jonas Preine, Bill Rhinehar, Masako Tominaga, Adam Woodhouse, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    Oral presentation

  • Rising from the Ashes: Scientific Drilling Sheds New Light on the Spatio-Temporal Evolution of the Kameni Volcano inside the Santorini Caldera
    Jonas Preine, Jens Karstens, Christian P Huebscher, Timothy H Drui, Steffen Kutterolf, Paraskevi Nomikou, Michael Manga, Sarah Beethe, Carole Berthod, Acacia Clark, Gareth James Crutchley, Susan M DeBari, Ralf Gertisser, Raymond M. Johnsto, Zenon Richard, P. Mateo, Iona M McIntosh, Katharina Pank, Ally Peccia, Thomas Ronge, Masako Tominaga, Hehe Chen, Shun Chiyonobu, Tatiana I. Fernandez Perez, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Olga Koukousiour, Molly C McCanta, Anthony Morris, Paraskevi Polymenakou, Adam Woodhouse, Yuzuru Yamamoto, Li Xiaohui, Abigail Metcalfe, Dimitrios Papanikolaou
    AGU Fall Meeting 2023, Dec. 2023, English
    [Invited]
    Invited oral presentation

  • A giant shallow-marine pyroclastic flow eruption from ancestral Santorini discovered by deep drilling (IODP Expedition 398)
    Timothy H Drui, Steffen Kutterolf, Thomas Ronge, Christian Huebscher, Paraskevi Nomikou, Jonas Preine, Ralf Gertisser, Joerg Keller, Olga Koukousioura, Michael Manga, Abigail Metcalfe, Molly C McCanta, Iona M McIntosh, Katharina Pank, Adam Woodhouse, Sarah Beethe, Carole Berthod, Shun Chiyonobu, Hehe Chen, Acacia Clark, Susan M DeBari, Raymond M. Johnsto, Ally Peccia, Yuzuru Yamamoto, Alexis Bernard, Tatiana I. Fernandez Perez, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Li Xiaohui, Antony Morris, Paraskevi Polymenakou, Masako Tominaga, Dimitrios Papanikolaou
    AGU Fall Meeting 2023, Dec. 2023, English
    Oral presentation

  • The story of heaven and hell (IODP Expedition 398) – Objectives, challenges and results of drilling into volcanic deposits of the Christiana-Santorini-Kolumbo volcanic field
    Steffen Kutterolf, Timothy H Drui, Thomas Ronge, Sarah Beethe, Alexis Bernard, Carole Berthod, Hehe Chen, Shun Chiyonobu, Acacia Clark, Susan M DeBari, Tatiana I. Fernandez Perez, Ralf Gertisser, Christian P Huebsche, Raymond M. Johnsto, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Olga Koukousioura, Li Xiaohui, Michael Manga, Molly C McCanta, Iona M McIntosh, Antony Morris, Paraskevi Nomikou, Katharina Pank, Ally Peccia, Paraskevi Polymenakou, Jonas Preine, Masako Tominaga, Adam David Woodhouse, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    [Invited]
    Invited oral presentation

  • The Influence of Magnetic Mineralogy on the Fidelity of Magnetostratigraphic Age Dating at IODP Sites in Contrasting Volcano-sedimentary Environments
    Antony Morris, Gunther Kletetschka, Alexander Roth, Christian Huebscher, Shun Chiyonobu, Olga Koukousioura, Adam Woodhouse, Timothy Drui, Steffen Kutterolf, Thomas Ronge, Sarah Beethe, Alexis Bernar, Carole Bertho, Hehe Chen, Acacia Clark, Susan M DeBari, Tatiana I. Fernandez Perez, Ralf Gertisser, Raymond M. Johnsto, Christopher Jones, Kumar Batuk Josh, Michael Manga, Molly C McCanta, Iona M McIntosh, Paraskevi Nomikou, Katharina Pank, Ally Peccia, Paraskevi Polymenakou, Jonas Preine, Masako Tominaga, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Structural characteristics of sediments in rift basins of Hellenic Island arc: Preliminary results on structural geology, IODP Exp.398
    Yuzuru Yamamoto, Hehe Chen, Yu-ki Sekiyama, Takeru Yoshimoto, Shun Chiyonobu, Adam David Woodhouse, Olga Koukousioura, Timothy H Drui, Steffen Kutterolf, Thomas Ronge, IODP Expedition 398 scientists
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Preliminary report on consolidation characteristics of sediments in the Christiana, Anafi and Anhydros basins, Greece (IODP Expedition 398)
    Takeru Yoshimoto, Yuzuru Yamamoto, Yu-ki Sekiyama, Adam Woodhouse, Shun Chiyonobu, Olga Koukousioura, Timothy H Drui, Steffen Kutterolf, Thomas Ronge, Christian Huebscher, Paraskevi Nomikou, Ralf Gertisser, Jonas Preine, Michael Manga, Abigail Metcalfe, Molly C McCanta, Iona M McIntosh, Katharina Pank, Sarah Beethe, Carole Bertho, Hehe Chen, Acacia Clark, Susan DeBari, Raymond Johnsto, Ally Peccia, Alexis Bernard, Tatiana I. Fernandez Perez, Kumar Batuk Joshi, Gunther Kletetschka, Li Xiaohui, Antony Morris, Paraskevi Polymenakou, Christopher Jones, Masako Tominaga, Dimitrios Papanikolaou, IODP Expeditio, scientists
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • After the Minoan: New Radiocarbon Ages of Recently Uncovered Eruptions in the Santorini Caldera
    Sarah Beethe, Maureen Walczak, Anthony A P Koppers, Olga Koukousioura, Adam Woodhouse, Jonas Preine, Timothy Drui, Steffen Kutterolf, Thomas Ronge, Alexis Bernar, Carole Bertho, Hehe Chen, Shun Chiyonobu, Acacia Clark, Susan M DeBari, Tatiana I. Fernandez Perez, Ralf Gertisser, Christian Huebscher, Raymond Johnsto, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Michael Manga, Molly C McCanta, Iona M McIntosh, Abigail Metcalfe, Antony Morris, Paraskevi Nomikou, Katharina Pank, Ally Peccia, Paraskevi Polymenakou, Masako Tominaga, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Detection of short-duration heating using RockEval pyrolysis and oxidation stages
    Yuzuru Yamamoto, Yu-ki Sekiyama, Yuino Kobayashi, Takeru Yoshimoto, Shun Chiyonobu, Stephen Bowden
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Maximum temperature of mudstone causeing heaving in tunnel
    Yu-ki Sekiyama, Kazuma Mochizuki, Takafumi Imai, Hikaru Ueno, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Tectonic evolution of the Neogene Miyazaki forearc basin derived from the physical properties of sediments and paleo-stress analysis
    Takeru Yoshimoto, Yasutomo Omori, Shun Chiyonobu, Feng Zhang, Yuzuru Yamamoto
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Deposits from a spectrum of shallow marine to subaerial explosive eruptions studied by deep drilling at Santorini (IODP Expedition 398)
    Timothy H Drui, Steffen Kutterolf, Jonas Preine, Ralf Gertisser, Jens Karstens, Joerg Keller, Christian Huebscher, Olga Koukousioura, Michael Manga, Molly C McCanta, Iona M McIntosh, Abigail Metcalfe, Paraskevi Nomikou, Katharina Pank, Thomas Ronge, Adam Woodhouse, Gareth James Crutchley, Sarah Beethe, Carole Berthod, Shun Chiyonobu, Hehe Chen, Acacia Clark, Susan M DeBari, Raymond M. Johnsto, Ally Peccia, Yuzuru Yamamoto, Alexis Bernard, Tatiana I. Fernandez Perez, Christopher Jones, Kumar Batuk Joshi, Gunther Kletetschka, Li Xiaohui, Antony Morris, Paraskevi Polymenakou, Masako Tominaga, Dimitrios Papanikolaou
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • Preliminary results of three-dimensional stress orientation in the Kumano forearc basin of the Nankai Subduction Zone, Japan by anelastic strain recovery measurements of core samples retrieved from IODP drilling sites C0025 and C0009
    Weiren Lin, Yuzuru Yamamoto, Timothy B Byrne, Yuhji Yamamoto, Nana Kamiya, Takehiro Hirose, Takatoshi Ito
    AGU Fall Meeting 2023, Dec. 2023, English
    Poster presentation

  • 付加体浅部の断層におけるせん断 による液状化発生過程に関する実験的研究
    田代 圭吾, 堤 昭人, 山本 由弦, Wang Gonghui, Chang Chengrui, Huang Chao
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Poster presentation

  • 三浦半島南部三崎層中に発達する インブリケート衝上断層の摩擦特性
    笠井 佑樹, 堤 昭人, 山本 由弦
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Poster presentation

  • 富山県上市町の下部中新統稲村水中地すべり堆積 物の内部構造解析における三次元デジタル露頭モ デルの構築と活用
    荒戸 裕之, 山本 由弦, 山田 泰広, 保柳 康一, 金子一夫, 國香 正稔, 白石 和也, 千代延 俊, 吉本 剛瑠, 関山 優希
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Poster presentation

  • トンネル内で盤ぶくれを引き起こ す泥質岩の最高経験温度
    関山 優希, 望月 一磨, 今井 啓文, 上野光, 山本 由弦
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Oral presentation

  • ロックエバル分析による短時間地質温度計の可能 性
    山本 由弦, 小林 唯乃, 関山 優希, 吉本 剛瑠, 千代延 俊, Bowden Stephen
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Oral presentation

  • 大学，民間企業，自治体，ジオパークの連携に よって再出現した巨大スランプ露頭
    金子 一夫, 荒戸 裕之, 山本 由弦, 山田 泰広, 白石, 和也, 千代延, 保柳 康一, 國香 正念, 吉本 剛瑠, 関山 優希
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Oral presentation

  • 堆積岩物性と応力逆解析から明ら かにする宮崎層群の発達史
    吉本 剛瑠, 大森 康智, 千代延 俊, 張 鋒, 山本 由弦
    日本地質学会第130年学術大会, Sep. 2023, Japanese
    Oral presentation

  • 付加体浅部の断層におけるせん断による液状化発生過程に関する実験的研究
    田代 圭吾, 堤 昭人, CHANG CHENGRUI, 山本 由弦, 王 功輝
    日本地球惑星連合2023年大会, May 2023, Japanese
    Poster presentation

  • 三浦―房総付加体の白子断層の断層ガウジにおけるナノスケール粒子破砕による間隙構造変化
    中元 啓輔, 亀田 純, 濱田 洋平, 山本 由弦
    日本地球惑星連合2023年大会, May 2023, Japanese
    Oral presentation

  • High temperature fluid flow through active décollement at the Nankai subduction zone, off Cape Muroto, Japan
    神谷 奈々, 木下 正高, 廣瀬 丈洋, 林 為人, Tsang Man-Yin, 山本 由弦, Bowden Stephen, 藤内 智士
    日本地球惑星連合2023年大会, May 2023, Japanese
    [Invited]
    Invited oral presentation

  • 被熱構造から見た足摺岬付加体-被覆層システムの形成と火成岩の貫入
    西沢 志穂, 山本 由弦
    日本地球惑星連合2023年大会, May 2023, Japanese
    Oral presentation

  • 軟岩に対する圧密試験の有用性と宮崎層群の発達史
    吉本 剛瑠, 千代延, 大森 康智, 張 鋒, 林 為人, 山本 由弦
    日本地球惑星連合2023年大会, May 2023, Japanese
    Oral presentation

  • 富山県上市町稲村地内の下部中新統折戸凝灰岩部層に挟在する水中地すべ り堆積物の変形構造
    荒戸裕之, 山本由弦, 山田泰広, 白石和也, 千代延 俊, 保柳康一, 金子一夫, 吉本剛瑠, 関山優希
    日本堆積学会 2023 年新潟大会, Apr. 2023, Japanese
    Oral presentation

  • High temperature fluid flow through active d&#233;collement at the Nankai subduction zone
    Nana Kamiya, Masataka Kinoshita, Weiren Lin, Takehiro Hirose, Yuzuru Yamamoto, Stephen A Bowden, Man-Yin Tsang, Satoshi Tonai
    EGU, Feb. 2023, English, Copernicus GmbH, &lt;p&gt;Temperature is one of the important parameters to understand complex dynamics, because temperature of the crust is changed by some events such as volcanic activities and a passage of high temperature fluid, which affects physical property, chemical cycle and also microbiosphere. Therefore, information about temperature allow us to understand the dynamics of the active subduction zone.&lt;/p&gt;&lt;p&gt;IODP Site C0023, located at the tip of subduction zone in the Muroto transect of the Nankai Trough, was drilled by IODP Expedition 370. There, we measured the vitrinite reflectance which is an index of the maximum temperature experienced by the sediments. Comparing the measured reflectance and the model values calculated by assuming the past heat flow, it was found that Site C0023 experienced a higher heat flow than the present, which was approximately 160 mW/m&lt;sup&gt;2&lt;/sup&gt;. However, the vitrinite reflectance is significantly higher than that in the above model just below the d&amp;#233;collement, which suggested that another thermal anomaly originated directly under the d&amp;#233;collement in addition to the high heat flow from the basement. With assumptions on the temperature of the heat source and the duration of heating below the d&amp;#233;collement, we calculated the vitrinite reflectance in different models.&lt;/p&gt;&lt;p&gt;As a result, it was found that heat source temperature of 200&amp;#730;C and heat generation duration of 500-1000 years are required just below the d&amp;#233;collement to explain the depth distribution of the measured values. At Site C0023, a high pore pressure zone is distributed just below the d&amp;#233;collement, which can serve as a path for fluids from deeper part. Considering that the temperature at the depth corresponding to the seismogenic zone in the Muroto area of the Nankai Trough is approximately 200&amp;#730;C, and that a specific high temperature has not been confirmed just below the d&amp;#233;collement of C0023 at present, the origin of the high-temperature fluid would be the deep seismogenic zone. Furthermore, the advection of high-temperature fluids is thought to be intermittent. In other words, the high reflectance just below the d&amp;#233;collement is considered to indicate the advection of the high-temperature fluid from deep to shallow areas at the time of past earthquakes.&lt;/p&gt;

  • Characteristics of Kikai caldera volcanic product revealed by seafloor drilling samples
    Nakaoka Reina, Kaneko Katsuya, Seama Nobukazu, Suzuki Keiko, Kiyosugi Koji, Hanyu Takeshi, Yamamoto Yuzuru, Matsuno Tetsuo, Satoshi Shimizu, Sugioka Hiroko, Yoshiyuki Tatsumi
    Annual Meeting of the Geochemical Society of Japan, Sep. 2022, Japanese, GEOCHEMICAL SOCIETY OF JAPAN, Kikai Caldera volcano has repeatedly erupted in large scale eruptions such as the Kikai Akahoya eruption 7,300 years ago and the Kikai Tozurahara eruption 95,000 years ago, and detailed eruption history can be studied by combining seafloor and on-land surveys.In this study, core samples were collected by the SCORE program of CHIKYU based on the subsurface structure revealed by seismic reflection surveys of large eruptive ejecta on the seafloor, which are still largely unknown.The chemical composition of the volcanic glass was analyzed and compared with subaerial deposits, and it was found that the two large-scale eruptive ejecta are thickly deposited on the seafloor as well, and that the Kikai Akahoya product is divided into two units on the seafloor as well.In addition, the chemical compositional characteristics of volcanic glass in piston core samples from a wide area around the Kikai caldera suggest that the Kikai Akahoya product may have become less accessible to distant sites as the eruption progressed.
    [Invited]
    Invited oral presentation

  • 鬼界カルデラ破局噴火の噴火準備過程 ―ちきゅうSCORE試料よりー
    羽生 毅, 常 青, 金子 克哉, 中岡 礼奈, 清杉 孝司, 鈴木 桂子, 山本 由弦, 松野 哲男, 島 伸和, 巽 好幸
    日本地球化学会年会, Sep. 2022, Japanese
    Oral presentation

  • Spatial distribution of heavy and carbonate minerals beneath the seafloor in the Nankai Trough and Shikoku Basin using X-ray CT data
    野村 夏希, 福島 颯, 藤内 智士, 久保 雄介, 木下 正高, 岡崎 啓史, Tsang Man-Yi, 山本 由弦, Bowden Stephen
    JpGU, Jun. 2022, Japanese
    Poster presentation

  • 室戸岬沖南海トラフのスロー地震震源域近傍に拡がるパッチ状高圧間隙水帯
    廣瀬 丈洋, 濱田 洋平, 谷川 亘, 神谷 奈々, 山本 由弦, 辻 健, 木下 正高, Heuer Verena, 稲垣 史生, 諸野 祐樹, 久保 雄介
    JpGU, Jun. 2022, Japanese
    Poster presentation

  • That other kind of oil; trans fatty acids and hydrogenation in the subseafloor hydrothermal system of Iheya Knoll
    Ogheneworo Offeh, Colin Taylor, Simone Fyfe, Akira Ijiri, Jun-ichiro Ishibashi, Yuzuru Yamamoto, Stephen Alan Bowden
    JpGU, May 2022, English
    Oral presentation

  • １次元熱伝導モデル解析が示す足摺岬花崗岩体貫入と前弧海盆三崎層群堆積の時間的関係
    西沢 志穂, 大森 康智, 林 為人, Bowden Stephe, 山本 由弦
    JpGU, May 2022, Japanese
    Oral presentation

  • プレート境界断層の高密度ランダム組織：力学実験からの検証
    山本 由弦、鈴木 雄大、栗本 悠平、張 鋒、阪口 秀
    JpGU, May 2022, Japanese
    Oral presentation

  • Recent Migration of Deep, Hot, Barite-forming Fluid in the Nankai Subduction Margin (IODP 370 Site C0023)
    Man-Yin Tsang, Shin Toyoda, Jun-ichiro Ishibashi, Stephen Bowden, Akira Ijiri, Shigeyuki Wakaki, Satoshi Tonai, Yuki Morono, Yuzuru Yamamoto
    JpGU, May 2022, English
    Oral presentation

  • Variation of consolidation characteristics among 3 facies in Miyazaki forearc basin, SW Japan
    吉本剛瑠, 千代延 俊, 大森 康智, 鈴木 雄大, 張 鋒, 山本 由弦
    JpGU, May 2022, Japanese
    Oral presentation

  • Paleo-thermal history deduced from vitrinite reflectance within the décollement, off Cape Muroto, Japan
    Nana Kamiya、Masataka Kinoshita、Weiren Lin、Takehiro Hirose、Yuzuru Yamamoto、Stephen Alan Bowden、Man-Yin Tsang、Satoshi Tona7、Expedition 370 Scientists Group
    JpGU, May 2022, Japanese
    [Invited]
    Invited oral presentation

  • Late Pleistocene to Holocene dynamic basin environment at the Osaka Bay: Stratigraphic expressions of tectonic deformation, sea level fluctuation, and tidal waves
    浜橋 真理, 大塚 宏徳, 鈴木 克明, 有元 純, 山本 由弦, 島 伸和, Bowden Stephe, 松野 哲男, 杉岡 裕子, 清水 賢, 井和丸 光, 佐野 守, 鈴木 啓太, 金子 克哉, 中東 和夫, 巽 好幸
    JpGU, May 2022, Japanese
    Oral presentation

  • 足摺花崗岩体周辺地域の被熱構造と熱物性
    西沢志穂, 大森康. 智, 林 為人, 千代延俊, 山本由弦
    日本地質学会第 128 年学術大会, Sep. 2021, Japanese
    Oral presentation

  • Geochemical variation of magma at Kikai Caldera volcano recorded in Chikyu SCORE tephra
    Hanyu T., Chang Q., Kaneko K., Suzuki-Kamata K., Nakaoka R., Kiyosugi K., Yamamoto Y., Seama N., Tatsumi Y.
    PROGRAMME AND ABSTRACTS THE VOLCANOLOGICAL SOCIETY OF JAPAN, 2021, Japanese, The Volcanological Society of Japan

  • High Fluid-Pressure Patches beneath the plate boundary fault: A Potential Source of Slow Earthquakes in the Nankai Trough off Cape Muroto
    Hirose Takehiro, Hamada Yohei, Tanikawa Wataru, Kamiya Nana, Yamamoto Yuzuru, Tsuji Takeshi, Kinoshita Masataka
    Annual Meeting of the Geological Society of Japan, 2021, Japanese, The Geological Society of Japan, Pore pressure plays a key role in the generation of earthquakes in subduction zones. However, quantitative constraints for its determination are quite limited. Here, we estimate the subsurface pore pressure by analyzing the transient upwelling flow of drilling mud from borehole C0023A of the International Ocean Discovery Program (IODP) Expedition 370, in the Nankai Trough off Cape Muroto. This upward flow provided the first direct evidence of an overpressured aquifer in the underthrust sediments off Cape Muroto (Figure). To estimate the pre-drilling pore pressure in the overpressured aquifer around a depth of 950–1050 meters below sea floor, we examined the measured porosities of core samples retrieved from nearby IODP wells; we then proceeded to explain the observed time evolution of the flow rate of the upwelling flow by modeling various sized aquifers through solving a radial diffusion equation. It was observed that for a permeability of 10–13 m2, the aquifer possessed an initial excess pore pressure of ~5 to 10 MPa above the hydrostatic pressure, with a lateral dimension of several hundred meters and thickness of several tens of meters. The overpressure estimates from the porosity-depth profile at Site C0023 differ from those at other drill sites in the region, suggesting the possible existence of multiple overpressured aquifers with a patchy distribution in the underthrust sediments of the Nankai Trough. As pore pressure is relevant in maintaining fault stability, the overpressured aquifers may be the source of slow earthquakes that have been observed around the drilling site.

  • K0条件下で種々の載荷を受ける海洋堆積物試料の力学特性と内部構造変化
    加藤優志, 福岡純一, 栗本悠平, 栗本悠平, 山本由弦, 阪口秀, 岩井裕正, CHO H
    地盤工学研究発表会発表講演集(CD-ROM), 2018

  • 南海付加体堆積物中の低熟成度炭質物ラマン分光分析とビトリナイト反射率の比較
    福地里菜, 山口飛鳥, 纐纈佑衣, 山本由弦, 芦寿一郎
    日本地質学会学術大会講演要旨, 2018

  • Structure of a post-middle Miocene Boso forearc basin, central Japan based on paleo-geothermal and consolidation characteristics
    Kamiya Nana, Yamamoto Yuzuru, Utsunomiya Masayuki, Fukuoka Junichi, Wang Qian, Zhang Feng, Lin Weiren
    Annual Meeting of the Geological Society of Japan, 2017, Japanese, The Geological Society of Japan, Program canceled for typhoon. However, This presentation was performed on the special session. This abstract is quotable and viewable on PDF.

  • Fluid pressure development beneath the decollement at the Nankai Trough off Cape Muroto, Japan
    Hirose Takehiro, Kamiya Nana, Yamamoto Yuzuru, Heuer Verena, Inagaki Fumio, Morono Yuki, Kubo Yusuke, Expedition Scientists
    Annual Meeting of the Geological Society of Japan, 2017, Japanese, The Geological Society of Japan, <b> [Program canceled for typhoon]</b> Program canceled for typhoon. However, This abstract is quotable and viewable on PDF.

  • Thermal decomposition of kaolinite and chlorite as a proxy for earthquake slip along an imbricate thrust fault in an accretionary prism
    Masumoto Hirokazu, Kameda Jun, Nagai Takaya, Arima Hiroshi, Sugiyama Kazumasa, Yamamoto Yuzuru
    Annual Meeting of the Geological Society of Japan, 2017, Japanese, The Geological Society of Japan, [Program canceled for typhoon] Program canceled for typhoon. However, This abstract is quotable and viewable on PDF.

  • 応力測定のためのコア定方位化:IODP第370次航海
    杉本達洋, 山本裕二, LIN Weiren, 山本由弦, 廣瀬丈洋, 神谷奈々, HEUER Verena, 稲垣史生, 諸野祐樹, 久保雄介, 前田玲奈
    日本地球惑星科学連合大会予稿集(Web), 2017

  • 紀伊半島沖海洋堆積物Site C0011の巨視的・微視的特性
    福岡純一, 栗本悠平, WANG Q., 張鋒, 岩井裕正, 山本由弦, 阪口秀
    地盤工学研究発表会発表講演集(CD-ROM), 2017

  • 小笠原前弧で採取された前弧玄武岩・ボニナイトの岩石物性と化学組成
    本多睦美, 道林克禎, 藤井昌和, 藤井昌和, 針金由美子, 山本由弦, 神谷奈々, 柵山徹也
    日本地球惑星科学連合大会予稿集(Web), 2017

  • 小笠原前弧域で掘削されたボニナイト・前弧玄武岩の岩石学的特徴と物性
    本多睦美, 道林克禎, 針金由美子, 柵山徹也, 山本由弦, 神谷奈々
    ブルーアース要旨集, 2017

  • IODP Site C0002にて採取されたカッティングス中の炭質物のラマン分光分析とビトリナイト反射率の比較
    福地里菜, 山口飛鳥, 纐纈佑衣, 山本由弦, 芦寿一郎
    日本地質学会学術大会講演要旨, 2017

  • 沈み込み帯浅部における地震性すべりの材料物質:房総半島石堂断層(OST)
    山本由弦, 福山繭子, 千代延俊, 千代延俊, 氏家恒太郎, 氏家恒太郎, 濱田洋平, 神谷奈々, 神谷奈々
    日本地質学会学術大会講演要旨, 2016

  • IODP Expedition 352で採取された前弧玄武岩とボニナイトの岩石物性研究
    本多睦美, 道林克禎, 山本由弦, 針金由美子, 神谷奈々, 渡邊了, 藤井昌和, 柵山徹也
    日本地質学会学術大会講演要旨, 2016

  • カッティングス試料のビトリナイト反射率測定・砕屑性ジルコン年代測定に基づく南海付加体深部構造の推定
    福地里菜, 山口飛鳥, 山本由弦, 伊藤久敏, 芦寿一郎
    日本地質学会学術大会講演要旨, 2016

  • Deformation and paleo-geothermal structure of the forearc basin in the southernmost of the Boso Peninsula, central Japan
    Kamiya Nana, Yamamoto Yuzuru, Takemura Takato
    Annual Meeting of the Geological Society of Japan, 2015, The Geological Society of Japan

  • Paleotemperature of the Nankai accretionary prism estimated by vitrinite reflectance of carbonaceous materials in cuttings retrieved during the IODP Expedition 348
    Fukuchi Rina, Yamaguchi Asuka, Yamamoto Yuzuru, Ashi Juichiro
    Annual Meeting of the Geological Society of Japan, 2015, The Geological Society of Japan

  • Ancient record of earthquake rupture in shallow portion of subduction zone: Ishido thrust (out-of-sequence thrust) in Boso Peninsula, central Japan
    Yamamoto,Yuzuru, Chiyonobu,Shun, Ujiie,Kohtaro, Hamada,Yohei, Kamiya,Nana, Saito,Saneatsu
    Annual Meeting of the Geological Society of Japan, 2015, Japanese, The Geological Society of Japan

  • Numerical Test on The Formation Mechanism of DecoUement Using Finite-Deformation FEM
    栗本 悠平, 山本 由弦, 阪口 秀
    計算工学講演会論文集 Proceedings of the Conference on Computational Engineering and Science, Jun. 2014, Japanese, 日本計算工学会

  • IODP第348次航海(南海トラフ地震発生帯掘削)におけるカッティングスによる岩相評価の有用性
    福地里菜, 山口飛鳥, 山本由弦, 芦寿一郎
    日本地質学会学術大会講演要旨, 2014

  • 沈み込み帯の深度2-4kmにおける変形と歪硬化
    LIN Weiren, 山本由弦, 濱田洋平, 千代延俊, 福山繭子, 亀田純
    日本地質学会学術大会講演要旨, 2013

  • 深度2-4kmに沈み込んだ房総半島南部保田付加体の構造および付加関連断層
    山本由弦, 千代延俊, 濱田洋平, 福山繭子, 亀田純, 山口はるか
    日本地質学会学術大会講演要旨, 2012

  • Spatial and time variations in stress state in the Costa Rica subduction margin, IODP Expedition 334
    Yamamoto Yuzuru, Lin Weiren, Usui Yoichi, Kanamatsu Toshiya, Saito Saneatsu, Zhao Xixi, Ujiie Kohtaro, Paola Vannucchi, Expedition 334 Scientists
    Annual Meeting of the Geological Society of Japan, 2012, The Geological Society of Japan

  • Suspension of diagenesis in the pre-subducting sediments and resulting faulting by the heterogeneity
    Kitamura Yujin, Kanamatsu Toshiya, Yamamoto Yuzuru, Kawamura Kiichiro, Novak Beth, Oda Hirokuni, Wu Huaichun, Yamamoto Tomohiro, Zhao Xixi
    Annual Meeting of the Geological Society of Japan, 2012, The Geological Society of Japan

  • P-108 Mineralogical characteristics of the Boso accretionary prism
    Kameda J., Yamamoto Y.
    日本地質学会学術大会講演要旨, Sep. 2008, Japanese, The Geological Society of Japan

  • Mineralogical characteristics of the Boso accretionary prism
    Kameda Jun, Yamamoto Yuzuru
    Annual Meeting of the Geological Society of Japan, 2008, Japanese, The Geological Society of Japan

  • Deformation properties in 2-3 km buried plate-boundary fault
    Yamamoto Yuzuru, Yamaguchi Haruka, Kameda Jun, Chiba Junichi
    Annual Meeting of the Geological Society of Japan, 2008, Japanese, The Geological Society of Japan

  • For application of U-Pb dating to the actual accretionary complex.
    Shibata Tadahiro, Orihashi Yuji, Yamamoto Yuzuru, Kinoshita Masataka
    Annual Meeting of the Geological Society of Japan, 2008, Japanese, The Geological Society of Japan

  • S-12 Internal texture of earthquake-induced submarine sliding
    Yamamoto Yuzuru, Suzuki Kiyofumi
    日本地質学会学術大会講演要旨, Sep. 2007, Japanese, The Geological Society of Japan

  • S-30 Primary deformation and related change of physical properties in an accretionary prism
    Yamamoto Yuzuru
    Annual Meeting of the Geological Society of Japan, 2006, Japanese, The Geological Society of Japan

  • Deformation phases and fabric change in accretionary prism. Yakushima Island. SW Japan
    YAMAMOTO Yuzuru, Tonogai Kazuki, ANMA Ryo
    Annual Meeting of the Geological Society of Japan, 2003, Japanese, The Geological Society of Japan

  • O-258 Deformation structures and strain distribution in sedimentary rocks in shallow and deep part of accretionary prisms
    YAMAMOTO Yuzuru, ANMA Ryo
    Annual Meeting of the Geological Society of Japan, 2002, Japanese, The Geological Society of Japan

  • O-221 Geometric Features of Shear Zones in the Shallow Part of the Accretionary Prism : An Example from Southern Part of the Boso Peninsula, Central Japan
    Yamamoto Yuzuru
    Annual Meeting of the Geological Society of Japan, 2001, Japanese, The Geological Society of Japan

  • O-204 Deformation process of the Nankai Trough accretionary prism : Results from ODP Leg 190 Site 1178
    Ujiie Kohtaro, Hisamitsu Toshio, Taira Asahiko, Yamamoto Yuzuru
    Annual Meeting of the Geological Society of Japan, 2001, Japanese, The Geological Society of Japan

■ Affiliated Academic Society
  • American Geophysical Union

  • JAPAN GEOSCIENCE UNION

  • THE GEOLOGICAL SOCIETY OF JAPAN

■ Research Themes
  • 地震断層活動時の摩擦発熱による有機炭素減少メカニズムの解明と防災研究への応用
    山本 由弦, 廣瀬丈洋
    日本学術振興会, 科学研究費助成事業, 基盤研究(A), 神戸大学, Apr. 2024 - Mar. 2029, Principal investigator

  • Development of geologically short-time thermometry and its application for earthquake mitigation
    山本 由弦, 千代延俊
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Challenging Research (Pioneering), Kobe University, Jul. 2021 - Mar. 2026
    本研究採択後、予定通りロックエバル装置のオートサンプラーの製作・修理に取りかかった。当初は自作を予定していたが、フランスVinci社が当該機器に合うオートサンプラーを製作できることになり、製作を依頼した。ただし、新型コロナウイルス流行のため技術者が来日できなかったので、取り付けや調整はこちらが実施した。その結果、自動で試料を炉にセットできるようになり、測定効率が飛躍的に改善された。 また、効率良く測定試料を準備するための試料ホルダを製作したほか、高額な試料るつぼ、Oリングのコストを削減するために、町工場と協力して製作を行った。 1年目に計画していたのは、従来の温度指標であるビトリナイトと、本研究で確立を目指すTmaxの相関検討である。これを実施するために、種子島、宮崎、四国の付加体と被覆層から試料を採取し、両者の相関検討を実施した。手持ちの試料を使って、紀伊半島と三浦・房総半島のパイロット検討も実施した。その結果、非常に良い相関が得られた。一方で、火成岩近傍はTmaxがトレンドから外れて高い値を示した。これによって、ビトリナイトよりもTmaxの方が短時間加熱にはるかに敏感であることが示された。さらに、両者の相関を確立させてTmaxから実際の被熱温度を計算するためには、火成岩の温度異常を除いたベースラインで相関式を検討する必要がある。そのため、この相関検討は継続的に実施し、より多くのデータを蓄積する必要があることも確かめられた。

  • High precision modeling for seabed rock mass and its application to clarify the mechanism of decollement formation
    張 鋒, 山本 由弦, 神谷 奈々, 岩井 裕正
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Nagoya Institute of Technology, 01 Apr. 2022 - 31 Mar. 2025

  • 断層粗さのマルチスケール測定：断層はどの程度デコボコしているのか
    武多 昭道, 山本 由弦, 山崎 勝也, 池田 大輔, 冨田 孝幸
    日本学術振興会, 科学研究費助成事業, 基盤研究(B), 東京大学, 01 Apr. 2021 - 31 Mar. 2025
    掘削孔からミューオン観測を行うための検出器開発、及び、房総半島での観測地点の調査を行った。 検出器開発については、主要な構成要素の開発を全て終えることができた。耐圧容器、耐圧コネクタ、シンチレータ、光検出器、電子回路の開発は完了している。耐圧容器と耐圧コネクタを製造し、岐阜県飛騨市跡津川断層の掘削孔内部での長期試験に着手した。耐圧容器はコストダウンのため、市販の上水道管を改造して製作した。耐圧コネクタも、コストダウンのため、自ら設計製作した。シンチレータと光検出器も製造が終了しており、組立作業を既に開始している。シンチレータの組立作業は、直径1.5mm長さ1mの穴の中に、直径1mm、長さ1.1ｍの波長変換光ファイバーを挿入して接着し、それに加えて光学グリスを気泡が入らないように挿入するという、非常に困難な作業であるが、光学グリスを真空容器に入れたまま、遠心分離にかけ、さらに真空容器中でグリスをシンチレータに挿入するという方法で解決した。遠心分離器は、コストダウンのため、市販の安価な洗濯機を使用した。電子回路はプロトタイプの製造と動作試験が完了しており、観測に使用する電子回路の製造の準備を完了させることができた。観測に用いる電子回路（48チャンネルFlashADC+TDCシステム）は、既製品が存在しないため、研究者自らで設計を行った。 房総半島での観測地点調査を10地点、2度に分けて行った。観測の容易さ、得られるデータの品質、電源インフラ・通信インフラ整備が可能か否か、等を総合的に評価し、観測地点を4地点に絞り込んだ。観測候補地は全て山間部であり、商用電源または太陽電池による電力確保が難しい場合があり、ミューオン観測に適した地点を探すことは容易ではなかったが、商用電源または太陽電池いずれかを用いれば観測が可能な、ミューオンによる断層透視に適した地点を決定することができた。

  • Construction of submarine landslide model: generation mechanics and motion pattern of Shizunai submarine landslide, off Hidaka, northern Japan
    荒戸 裕之, 千代延 俊, 山田 泰広, 山本 由弦
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Akita University, 01 Apr. 2019 - 31 Mar. 2024
    令和2年度は、年初計画に従って以下の検討項目を実施してきた。 (1) 地すべり堆積体の内部構造および外部形態の把握：三次元地震探査データの堆積学的、構造地質学的解析を継続し、より詳細な内部構造の特徴を洗い出すとともに、外部形態や盆地内のセッティングと内部変形構造の関係等についてより詳細な検討を行なった。 (2) 追加海洋地震探査データ収録の提案：静内海底地すべり堆積体の特徴をより明瞭に把握できる位置を選定してその海域に測線を設定し、これに沿った詳細二次元地震探査記録の収録を実施機関に対して提案した。 (3) 浅層コア（SCORE）採取提案：静内海底地すべり堆積体の挙動およびその原因を究明するために最適な堆積物試料採取地点（海域）の選定を行い、地球深部探査船「ちきゅう」の運行機関に対してそのサイトにおける浅層コア（SCORE）掘削計画を提案した。 なお、以上の検討作業に際しては、当初、対面での研究打ち合わせ会議を計画していたが、政府、自治体および代表者・分担者の研究機関が示すCOVID-19予防対策を遵守するため、原則としてオンラインでの打ち合わせにより検討作業を進めてきた。

  • Quantitative evaluation of frictional heat of the Futagawa fault ruptured during the Kumamoto Mw 7.1 earthquake and investigation of singular temperature structure in the area
    林為人, 木下 正高, 山本 由弦, 濱田 洋平
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), Kyoto University, Apr. 2019 - Mar. 2024
    熊本地震本震の震源断層である布田川断層を貫く、最大深度700mの鉛直調査孔（FDB）が阿蘇火山地域に位置する益城町で掘削された。本研究は、FDB孔を利用して布田川断層の地震時動的すべりの摩擦熱による温度分布の異常を正確に検出し、地震時の断層すべり特性である動的摩擦係数の決定を主目的としている。この目的を達成するために、掘削孔内の温度を高精度で約3年間継続的に測定する計画である。令和3年度には、これまでの2か年に続き、①FDB孔内に複数の高精度温度センサーを低い定速度で降下・上昇させながら温度の連続プロファイルの計測を定期的に計3回繰り返し実施したほか、②温度異常の可能性がある深度や温度プロファイルの変曲点など、重要な深度に温度センサーを15個以上設置して、連続経時変化の定点観測を行った。また、FDB孔内において、透水係数を評価するための注水試験とともに、孔内の水を採水して水質分析も実施することができた。 FDB掘削孔のコア試料ならびに検層データを用いて、地質構造の詳細解析を行った結果、布田川断層での200 mを超える垂直落差の発見に至り、阿蘇火山のカルデラ噴火と関係して断層運動のパターンは縦ずれから横ずれへ変化したことを突き止めた。また、地質構造と孔内物性を総合的に検討した結果、FDB孔の深度461mで認められた断層が、2016年の熊本地震の本震時に滑った断層の最有力候補であることも判明した。これらの成果を取りまとめ、有力な国際学術雑誌に論文を掲載し、研究代表者の所属機関である京都大学から研究成果のプレスリリースが行われた。また、孔内の温度分布を影響する地下水の流動を大きく左右する有効間隙率を検討するために、音波検層データにより全区間の有効間隙率を推定し、学術雑誌『材料』に原著論文を掲載することができた。

  • Barite in plate subduction margins: Timing and origin of hot fluid
    山本 由弦, TSANG MAN YIN
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Kobe University, 13 Nov. 2020 - 31 Mar. 2023, Principal investigator
    IODP Exp370において採取された重晶石のESR年代測定の有効性を確かめることができた。2021年12月に、国際誌（Quaternary Geochronology）に論文原稿を投稿した。2021年度中は査読中であったが、2022年度に入り、受理された。2022年度に入り、年代データをさらに得るための試料処理と実験を実施している。 重晶石を晶出させた高温流体の起源を明らかにするため、2021年度に高知コア研究所においてストロンチウム同位体の検討を実施した。その結果を前年度までに得られていた他の地球化学データと合わせて考えると、流体の起源は単一ではなく、複数が混合していることが明らかになった。この妥当性とさらなる確認のために、2022年度のJpGUにて発表と議論を予定している。

  • Shear-strength variation along subducting mega-thrust- their influence on the geometry of accretionary prism
    山本 由弦, 古市 幹人, 西浦 泰介
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Japan Agency for Marine-Earth Science and Technology, Apr. 2019 - Mar. 2023
    前年度までに得ていた、沈み込み帯3-4 kmの断層岩と母岩のせん断応力の違いについて、数値シミュレーションで再現することに成功した。3軸圧縮実験によって得られた断層強度変化データを付加体スケールのシミュレーションにおいて使用するために、周期境界を満たす粒子供試体を作成し、その破壊挙動が得られたサンプルと等しくするためのキャリブレーション実験を実施した。その結果、サンプルと同様の破壊包絡線を示す粒子群を作成することに成功し、次年度に予定する付加体形成シミュレーションの準備が完了した。 また今年度は、本研究課題に関する国際招待講演を1件（CCP-WSI Code Developers’ Workshop）、国内の学会発表2件を行った。

  • 南紀熊野ジオパークの温度・地質構造：海陸構造統合とジオサイトの形成機構解明
    山本由弦, 常盤哲也, 千代延俊
    和歌山県, 南紀熊野ジオパーク研究助成金, Jul. 2019 - Mar. 2022, Principal investigator

  • 竜串海岸が記録する足摺花崗岩体の上昇過程 -三崎層群の熱伝導度測定からのアプローチ-
    高知県土佐清水市, 令和2年度 土佐清水ジオパーク構想活動支援事業, Jun. 2020 - Feb. 2021, Principal investigator

  • 地質学･地盤工学的見地から海底岩盤の力学挙動の高精度モデル化
    張 鋒
    日本学術振興会, 科学研究費補助金 基盤研究B, Apr. 2017 - Mar. 2020
    Competitive research funding

  • 土佐清水ジオパーク・地質のきほん
    山本由弦, 千代延俊
    土佐清水市, 土佐清水ジオパーク構想活動支援事業（学術研究事業）, Jun. 2019 - Feb. 2020, Principal investigator

  • Study on the Boso slow slip events through observation using ocean bottom pressure gauges and model simulation
    SATO Toshinori, SHIBAZAKI Bunichiro, MOCHIZUKI Kimihiro, YAMADA Tomoaki, ITO Hisao, KOBAYASHI Reiji, YAMAMOTO Yuzuru
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Chiba University, 01 Apr. 2013 - 31 Mar. 2018
    We conducted the following studies to reveal the Boso slow slip events (SSEs).We observed crustal movements using ocean bottom pressure gauges to estimate slip distribution of the Boso SSE, and obtained them successfully caused by the 2014 Boso SSE. We developed an analysis method using a parametric model for data of pressure gauges. We conducted analyses on seismic structure of off the Boso area and simulation studies that reproduce a series of the Boso SSEs. We obtained a configuration of the upper surface of the Philippine Sea plate at off the Boso area. We found strong reflections from the upper surface around the Boso SSE region. We could make a simulation model which reproduced the Boso SSEs before 2011, but could not reproduce the 2014 SSE. To make a simulation model reproducing all of the Boso SSEs is an issue to be addressed to the future.

  • Investigation on the formation mechanism of the decollement zone in the viewpoint of geomechanics
    Zhang Feng, Sakaguchi Hide, Yamamoto Yuzuru
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Challenging Exploratory Research, Nagoya Institute of Technology, 01 Apr. 2013 - 31 Mar. 2016
    Based on the assumption that cyclic loadings may be a main reason for the formation of décollement, siltstone and remolded Fujinomori clay are tested with static/dynamic loads. Meanwhile, anisotropy of magnetic susceptibility (AMS) and SEM are also measured to check the changes of micro-structure of the tested specimen. It is found that no major fabric variation happened though deformation occurred due to cyclic loadings, which is exactly the same as the characteristics of décollement. Furthermore, the process of the oceanic plate subducting beneath into continental plate and the dynamic loading of earthquake are simulated by numerical tests to investigate their influence on décollement. It is found that, the simulated results are similar to the observed micro-structural characteristics of décollement. In other words, the repeated dynamic loading due to earthquake is apparently the main mechanism to form the décollement zone.

  • 沈み込みプレート境界における有効摩擦係数の地震サイクルに伴う時空間変化
    橋本 善孝
    日本学術振興会, 科学研究費補助金 基盤研究B, Apr. 2012 - Mar. 2015
    Competitive research funding

  • 巨大地震断層の物質科学的研究によるすべりメカニズムの解明
    木村 学
    文部科学省, 新学術領域研究（計画研究）, Apr. 2012 - Mar. 2014
    Competitive research funding

  • Stress measurements in the Scientific Drilling Projectof 2008 Wenchuan Earthquake Fault, China
    LIN Weiren, YAMAMOTO Yuzuru
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Japan Agency for Marine-Earth Science and Technology, Apr. 2010 - Mar. 2012
    To investigate relations of fault rupturing during a great earthquake and stress change, we tried to determine in situ stress state both in Wenchuan Earthquake Fault Scientific Drilling Project (WFSD) and in Japan Trench Fast Drilling Project (JFAST) penetrating through the fault ruptured during 2011 M9 Tohoku-Oki earthquake. We found that in-situ horizontal stress in the vicinity of the Tohoku-Oki earthquake fault decreased during the earthquake distinctly. The stress change suggests an active slip of the frontal plate-interface consistent with coseismic fault weakening and a nearly total stress drop.
    Competitive research funding

  • 沈み込み帯に持ち込まれる堆積物の不均質性とデコルマゾーン形成時の挙動
    山本 由弦
    文部科学省, 科学研究費補助金 新学術領域研究, 新学術領域研究(研究領域提案型), 独立行政法人海洋研究開発機構, Apr. 2010 - Mar. 2012, Principal investigator
    本研究は,プレート沈み込み帯に持ち込まれる堆積物中にデコルマゾーンが形成されるメカニズムの解明を目指すものである.室戸沖南海付加体では,粘土鉱物が弱くセメントされた層準にデコルマゾーンが発達することが報告されている.弱くセメントされた泥質岩は,繰り返し載荷に対して脆弱であるという性質があるため,デコルマゾーン形成メカニズムにはプレート境界特有の有効応力変動(地震波や間隙水圧の伝播などに起因)が鍵を握っていると考えた.本研究では,この有効応力変動を再現できる圧密試験機(等方圧密)を開発した.試験機は,最大封圧20MPa,封圧変動を最速5Hz与えられる仕様である. 本年度は,主に房総半島の海溝斜面堆積物(堆積年代は約2.8Ma)を用いて試験を行った.試験は,通常の圧密試験(封圧変動なし)によって得られた降伏圧密強度までいったん封圧を上昇させ,そこから任意の周波数・応力変動を与えた.等方圧密方式を採用しているため,理論的には組織の異方性には変化が起こらないはずである.実際,通常の圧密試験後の試料と試験前の試料では,異方性に違いは見られなかった.ところが,封圧変動を作用させると地層面に平行な方向に面構造がより発達する.試料を地層面に対して垂直および水平に整形しても同じ結果が確認されたことから,異方性は堆積構造異方性がより強調される傾向にあることが判明した.これらの結果は,上載荷重による圧密に比べ,有効応力変動による組織改編および物性変化が劇的なものであることを示している.プレート沈み込み帯のような変動帯では,これらを評価することが必要である.また,デコルマゾーンが形成されるメカニズムの解明をめざし,昨年行われたExp.333で採取された,デコルマゾーンの材料物質というべきセメント層準を採取した.今後これら試料を用いてデコルマ形成の再現試験を行う予定である.
    Competitive research funding

  • Deformation and processes of physical evolution of sediments in 2-3 km burial depth at subduction zone
    YAMAMOTO Yuzuru
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Japan Agency for Marine-Earth Science and Technology, Apr. 2009 - Mar. 2011, Principal investigator
    Change in deformation styles and the related transition from smectite to illite within the aseismic-seismic transition zone (2-4 km below the seafloor) in a subduction zone were analyzed by studying an onland accretionary complex that was previously buried to a depth of just 2-4 km. Such strain hardening associated with the clay mineral transition and decrease in porosity is the primary mechanism of thickening of the decollement and/or melange zone, and represents a fundamental mechanical/chemical change in the properties of sediments immediately before entering the seismogenic zone.
    Competitive research funding

  • 南関東アスペリティ地域掘削・長期孔内計測の為の国際ワークショップ開催
    小林 励司
    地球科学技術総合推進機構, IODP 掘削プロポーザル作成支援課題, Apr. 2008 - Mar. 2009
    Competitive research funding

  • フィッショントラック法を使用した付加体成長速度の定量算出
    山本 由弦
    日本科学協会, 笹川科学研究助成金, Apr. 2008 - Mar. 2009, Principal investigator
    Competitive research funding

  • Deformation, physical evolution of sediments during initial accretion processes and related variation of hydraulic properties
    YAMAMOTO Yuzuru
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Apr. 2007 - Mar. 2009, Principal investigator
    付加体形成初期の変形にともなう物性変化を被っている堆積物は,肉眼や顕微鏡下で変形構造が確認されないものの,粒子の配列様式と透水特性が大きく異なることが判明した.変形に伴って物性変化を被った堆積物は,被っていない堆積物に比べ最大25%にまで透水係数が小さくなった.また,物性変化を被った堆積物は,地震発生帯上限付近に対応する封圧80MPa付近において,間隙率が急減することが確認され,その深度領域において間隙水を急激に排出し,周辺の強度低下をもたらしている可能性を示した.
    Competitive research funding

  • 南関東アスペリティ地域掘削・長期孔内計測の為の国際ワークショップ開催
    小林 励司
    地球科学技術総合推進機構, IODP 掘削プロポーザル作成支援課題, Apr. 2007 - Mar. 2008
    Competitive research funding

  • 南関東アスペリティ地域のライザー掘削及び長期孔内計測
    小川 勇二郎
    地球科学技術総合推進機構, IODP 掘削プロポーザル作成支援課題, Apr. 2006 - Mar. 2007
    Competitive research funding

  • 付加体浅部から深部に至る堆積物の変形と物性変化の相関
    山本 由弦
    日本学術振興会, 科学研究費補助金特別研究員奨励費, 特別研究員奨励費, 静岡大学, Apr. 2003 - Mar. 2006, Principal investigator
    本年度は,初頭にIODP EXP308「Gulf of Mexico Hydrogeology」に参加した.その目的は,付加体浅部の剪断と堆積物物性変化の相関を明らかにするために,そのアナログとして同地域に発達する巨大地すべり岩体に注目し,地すべり剪断による堆積物の物性・ファブリック,それに透水特性変化の相関を検討するものである.初期の結果は,IODP Preliminary Reportにおいて発表された. 陸域に唯一露出する浅部付加体として注目される三浦・房総付加体について,初めての総括的な構造地質論文をまとめ,国際誌Tectonicsに掲載された.本付加体は,はぎ取り付加によって形成された付加体で,(1)プレート境界の分岐断層,(1)により陸側に付加した地質帯のうち,(2)衝上断層系など剪断変形が集中した下部,(3)剪断変形をほとんど被っていない上部,に対応する3つのユニットに区分された.最大埋没深度は1000メートル以浅,最高被熱温度は50℃以下,そして付加作用による総隆起量は1000-1500メートルであると示された. 各ユニットにおける各種物性解析やファブリック解析によって,沈み込み帯前縁部の歪史および物性変化過程を明らかにし,国際誌Earth and Planetary Science Lettersに受理された.各ユニットがそれぞれ(1)付加体浅部域プレート境界断層,(2)付加体浅部で最初期に形成される過圧密堆積物,(3)付加に伴う剪断歪みを被っていない正規圧密堆積物をそれぞれ保存していることが明らかとなった.特に,プレート境界断層発達以前に,先駆的な剪断歪みによって過圧密堆積物が形成され,後の歪み集中,最終的にはプレート境界断層の発達に大きな制約を与えていることを明らかにした. 本年後半は,京都大学においてガス圧透水試験機を用いた間隙率・浸透率変化モニタの実験を行った.付加体浅部で剪断によって形成された過圧密堆積物が,付加体深部や地震発生帯上限付近まで流体を持ち込み,周辺物質の強度低下を引き起こしている可能性が明らかになった.付加体浅部の変形が深部変形に大きな影響を与えうるという世界初の知見であり,今後も検証が求められる.
    Competitive research funding

  • 付加体浅部および深部の野外調査に基づく堆積物の変形と物性変化に関する比較研究
    山本 由弦
    深田地質研究所, 深田研究助成, Apr. 2002 - Mar. 2003, Principal investigator
    Competitive research funding

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