Updated on 2026/07/10

写真a

 
NAGAYA, Takayoshi
 
Affiliation
Faculty of Education and Integrated Arts and Sciences, School of Education
Job title
Associate Professor
Degree
PhD ( 2016.03 Nagoya University )
Mail Address
メールアドレス
Homepage URL
https://w-rdb.waseda.jp/html/100004383_en.html
Profile

研究室ウェブサイト: https://struct-geosci.w.waseda.jp/

Laboratory website: https://struct-geosci.w.waseda.jp/en/

Research Experience

  • 2025.04
    -
    Now

    Waseda University   Department of Earth Sciences, Department of Science, School of Education, Faculty of Education and Integrated Arts and Sciences   Associate Professor

  • 2023.04
    -
    2025.03

    Tokyo Gakugei University   Department of Environmental Science, Broad-Scope Natural Sciences, Natural Sciences Division, Faculty of Education   Lecturer

  • 2019.09
    -
    2023.03

    The University of Tokyo   School of Science   Assistant Professor

  • 2019.04
    -
    2019.08

    University of Southern California   Dornsife College of Letters, Arts and Sciences   JSPS Overseas Research Fellow

  • 2016.04
    -
    2019.03

    Tohoku University   Graduate School of Environmental Studies   Japan Society for the Promotion of Science (JSPS) Postdoctoral Research Fellow (PD)

  • 2013.04
    -
    2016.03

    Nagoya University   Graduate School of Environmental Studies   Japan Society for the Promotion of Science (JSPS) Research Fellow (DC1)

  • 2023.10
    -
    Now

    The University of Tokyo   Graduate School of Science   Guest Researcher

  • 2025.04
    -
    2026.03

    Tokyo Gakugei University   Faculty of Education   Part-time Lecturer

  • 2017.10
    -
    2019.08

    University of Southern California   Dornsife College of Letters, Arts and Sciences   Post-Doctoral Scholar–Visiting Fellow

  • 2015.09
    -
    2016.03

    Aichi Institute of Technology   Center for General Education   Part-time Lecturer

  • 2014.09
    -
    2015.03

    Aichi Institute of Technology   Center for General Education   Part-time Lecturer

▼display all

Education Background

  • 2013.04
    -
    2016.03

    Nagoya University   Graduate School of Environmental Studies   Department of Earth and Planetary Sciences  

  • 2011.04
    -
    2013.03

    Nagoya University   Graduate School of Environmental Studies   Department of Earth and Planetary Sciences  

  • 2007.04
    -
    2011.03

    Osaka Prefecture University   School of Science   Department of Physical Science  

Committee Memberships

  • 2024
    -
    2025

    Japan Association of Mineralogical Sciences (JAMS)  Research Presentation Excellence Award Selection Committee: Member

  • 2019.11
    -
    2023.12

    The 17th International Symposium on Water-Rock Interaction (WRI-17) organizing committee  Local organizing committee

  • 2021
    -
    2022

    The Geological Society of Japan (GSJ)  Election Administration Committee member

  • 2021
    -
    　

    Metamorphic etc Symposium 2021  Virtual Organizing Committee

  • 2017
    -
    　

    Metamorphic etc Symposium 2017 & 14th International Symposium on Water Dynamics Joint meeting  organizing committee

Professional Memberships

  • 2014
    -
    Now

    The Seismological Society of Japan (SSJ)

  • 2012
    -
    Now

    The Geological Society of Japan (GSJ)

  • 2012
    -
    Now

    Japan Association of Mineralogical Sciences (JAMS)

  • 2012
    -
    Now

    Japan Geoscience Union

  • 2020
    -
    2022

    Asia Oceania Geosciences Society (AOGS)

  • 2018
    　
    　

    American Geophysical Union (AGU)

  • 2016
    　
    　

    American Geophysical Union (AGU)

  • 2014
    　
    　

    American Geophysical Union (AGU)

  • 2014
    　
    　

    The European Geosciences Union (EGU)

  • 2012
    　
    　

    American Geophysical Union (AGU)

▼display all

Research Areas

  • Solid earth sciences

Research Interests

  • Interior Earth Materials Science, Structural Geology, Petrology, Metamorphic Rocks, Serpentinite, Mineral Physics

  • Solid Earth Physics, Structural Seismology, Subduction Zone, Upper Mantle, Continental Crust, Rock Structure, Seismic Anisotropy

  • EBSD, XRD, Raman spectroscopy, EPMA, SEM

  • Geoscience education, rock and mineral specimens, large-scale language models, generative AI

Awards

  • 日本地質学会 学生優秀発表賞

    2025.09   日本地質学会   接触変成作用に伴う超苦鉄質岩類の熱変成反応と流体活動：赤石山地北部・三波川帯の例

    Winner： 延原香穂, 森宏, 築島由理恵, 永冶方敬, 新屋貴史, 早川由帆, 山岡健, 原英俊, 藤本光一郎, 常盤哲也

  • 日本地質学会 学生優秀発表賞

    2025.09   日本地質学会   ドローン磁気探査による蛇紋岩分布の抽出：赤石山地北部・三波川帯の例

    Winner： 國谷 七海, 森 宏, 宿輪 隆太, 安井 悠人, 延原 香穂, 大熊 茂雄, 宮川 歩夢, 常盤 哲也, 小澤 和浩, 山岡健, 永冶 方敬, 村上 大知

  • Geological Society of JapanStudent Outstanding Presentation Award

    2024.09   The Geological Society of Japan (GSJ)   Estimation of maximum shear stress along the subduction plate interface and reexamination of subduction zone thermal modeling: example from the Late Cretaceous Sambagawa subduction zone

    Winner： Yukinojo KOYAMA, Simon WALLIS, Takayoshi NAGAYA, Mutsuki AOYA

  • Japan Association of Mineralogical Sciences Student Presentation Award

    2024.09   Japan Association of Mineralogical Sciences (JAMS)   Toward the establishment of "EBSD method for the detection of quartz with phase transition to coesite": Incorporation of the Gongen area, Sanbagawa metamorphic belt, Shikoku, SW-Japan

    Winner： Momoko Minowa, Takayoshi Nagaya, Taisuke Ito, Simon Wallis

  • Geological Society of JapanStudent Outstanding Presentation Award

    2023.09   The Geological Society of Japan (GSJ)   Serpentinization and Contact metamorphism processes based on spatial variation of mineral combinations in ultramafic rocks of the Sanbagawa Belt, Ina area, Nagano Prefecture, Japan

    Winner： Kaho NOBUHARA, Yurie TSUKISHIMA, Hiroshi MORI, Takayoshi NAGAYA, Takafumi SHINYA, Yuho HAYAKAWA

  • Geological Society of JapanExcellent Poster Award

    2017.09   The Geological Society of Japan (GSJ)   Nucleation of 10 μm-scale olivine grains in chlorite peridotite due to dynamicrecrystallization

    Winner： Komai, M., Mizukami, T., Arai, T., Nagaya, T. & Wallis, S.

  • Geological Society of JapanExcellent Poster Award

    2015.09   The Geological Society of Japan (GSJ)   Petrological and field evidence for the importance of brucite in the shallow mantle wedge of the Sanbagawa subduction zone

    Winner： Kawahara, H., Endo, S., Wallis, S., Nagaya, T., Mori, H., Yamamoto, K, & Asahara, Y.

  • Japan Geoscience Union (JpGU) Meeting 2015 Outstanding Student Presentation Award (OSPA)

    2015.05   Japan Geoscience Union (JpGU)   S-wave ray path analysis constrains the distribution and dynamics of the hydrated mantle wedge

    Winner： Takayoshi Nagaya, Simon Wallis, Andrew Walker, James Wookey & Michael Kendall

    　View Summary

    https://confit.atlas.jp/guide/event-img/jpgu2015/01345/public/pdf?type=in

  • Geological Society of JapanExcellent Poster Award

    2014.09   The Geological Society of Japan (GSJ)   Constraints on Time-scales for Graphitization of Carbonaceous Material

    Winner： Mori, H., Mori, N., Wallis, S., Annen, C., Westaway, R., Caricchi, L., Kouketsu, Y. & Nagaya, T.

  • Geological Society of JapanExcellent Poster Award

    2014.09   The Geological Society of Japan (GSJ)   Interactions between the shallow wedge mantle and subducted slab ~ the Shiraga ultramaficbody, Kochi prefecture ~

    Winner： Kawahara, H., Nagaya, T., Mori, H. & Wallis, S.

▼display all

 

Papers

  • EBSD map analysis for antigorite deformation micro-textures related to dislocations: Implications for the effect of antigorite crystal structure on plastic deformation

    Takayoshi NAGAYA, Simon R. WALLIS, Seiichiro UEHARA

    Journal of Mineralogical and Petrological Sciences   121 ( 1 )  2026.03  [Refereed]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

  • Grain boundary sliding as a formation mechanism for the crystal preferred orientation of antigorite: the formation and development of B-type antigorite CPO patterns

    Takayoshi Nagaya, Simon R. Wallis

    Progress in Earth and Planetary Science   13 ( 4 )  2026.01  [Refereed]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    1
    Citation
    (Scopus)

  • Fluid behavior in ultramafic rocks promoted by contact metamorphism: An example from the Sanbagawa Belt, northern Akaishi Mountains, central Japan

    Kaho NOBUHARA, Hiroshi MORI, Yurie TSUKISHIMA, Takayoshi NAGAYA, Kuniaki MAKINO, Ken YAMAOKA, Takafumi SHINYA, Yuho HAYAKAWA, Tetsuya TOKIWA, Wataru TANAKA

    Journal of Mineralogical and Petrological Sciences   121  2026

    DOI

    Scopus

  • The electron backscatter diffraction (EBSD) analysis procedure for crystal preferred orientations to reduce loss of EBSD map data: An example of antigorite

    Takayoshi NAGAYA, Simon R. WALLIS

    Journal of Mineralogical and Petrological Sciences    2025.07  [Refereed]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    2
    Citation
    (Scopus)

  • Progressive change in dislocation microstructures in shocked calcite with pressure: Characterization of micrometeoroid bombardment on asteroid Ryugu

    Naotaka Tomioka, Kosuke Kurosawa, Akira Miyake, Yohei Igami, Takayoshi Nagaya, Takaaki Noguchi, Toru Matsumoto, Masaaki Miyahara, Yusuke Seto

    American Mineralogist   110 ( 6 ) 945 - 955  2025.06  [Refereed]

    　View Summary

    <jats:title>Abstract</jats:title>
    <jats:p>Shock recovery experiments were performed using a two-stage light gas gun to clarify the progressive deformation microstructures of calcite at the submicron scale concerning pressure. Decaying compression pulses were produced using a projectile that was smaller than the natural marble target. In two experiments, natural marble samples were shocked to 13 and 18 GPa at the epicenters of the targets. Calcite grains shocked in the pressure range of 1.1–18 GPa were examined using polarized light microscopy and (scanning) transmission electron microscopy. The density of free dislocations in the grains shocked at 1.1–2.2 GPa [108–9 (cm-2)] is comparable to that of unshocked Carrara calcite grains. Subparallel bands of entangled dislocations less than 1 µm are formed at 4.2 GPa, and strongly entangled dislocations spread throughout the focused ion beam (FIB) sections at 7.3–18 GPa pressures. Dislocations selectively nucleate and entangle near the slip planes at pressures above ~3 GPa, corresponding to the transition from sharp extinction to undulatory extinction, according to the microstructural evolution with shock pressure. Above approximately 6 GPa, the dislocations nucleated homogeneously throughout the calcite crystals. The dislocation microstructure in a calcite grain collected from the asteroid Ryugu particle is similar to that of the experimentally shocked calcite at 4.2 GPa. The estimated pressure of 2–3 GPa, determined through fault mechanics analyses and the presence of dense sulfide minerals in the Ryugu particles, is in line with this pressure.</jats:p>

    DOI

    Scopus

    7
    Citation
    (Scopus)

  • Detailed Occurrence of Feather Features in Quartz in Experimentally Shocked Granite

    Toshihiro Tada, Kosuke Kurosawa, Naotaka Tomioka, Takayoshi Nagaya, Junko Isa, Christopher Hamann, Haruka Ono, Takafumi Niihara, Takaya Okamoto and Takafumi Matsui

    Journal of Geophysical Research: Planets    2024.10  [Refereed]

    DOI

    Scopus

    4
    Citation
    (Scopus)

  • Evidence for suboceanic small-scale convection from a “garnet”-bearing lherzolite xenolith from Aitutaki Island, Cook Islands

    Norikatsu Akizawa, Kazuhito Ozawa, Tetsu Kogiso, Akira Ishikawa, Akira Miyake, Yohei Igami, Simon R. Wallis, Takayoshi Nagaya, Chihiro Ohshima, Ryo Fujita, Tatsuhiko Kawamoto, Akihiro Tamura, Tomoaki Morishita, Shoji Arai and Atsushi Yasumoto

    Progress in Earth and Planetary Science (PEPS)   11:38   1 - 28  2024.07  [Refereed]

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>Garnet peridotite xenoliths have been rarely reported from suboceanic mantle. Petrographic and geochemical characteristics of garnet-bearing oceanic peridotite xenoliths provide precious information on dynamics of the suboceanic lithosphere and asthenosphere interaction. We examined a lherzolite xenolith included in olivine nephelinite lava from Aitutaki Island, a member of the Cook-Austral volcanic chain. The lherzolite xenolith contains reddish fine-grained (&lt; 5 µm in size) mineral aggregates (FMAs) with size range of 0.5–6 mm, consisting of olivine, calcic and sodic plagioclases, aluminous spinel, native iron, and nepheline. Microstructural observations and chemical data corroborate that the FMA is a decomposed pyrope-rich garnet including chromian spinel grains with an irregular highly indented morphology in the center. The FMA is surrounded by pyroxene-poor and olivine-rich aureole. The spatial and morphological relationships of FMA and chromian spinel with pyroxene-depleted margin suggest a reaction of aluminous spinel + pyroxenes → pyrope-rich garnet + olivine, which requires a compression before decomposition of the garnet to FMA. An orthopyroxene grain shows slight but clear chemical zoning characterized by increase in Al, Ca, and Cr from the grain center to the rim. The zoning patterns of Al and Ca in the orthopyroxene grain can be modeled by diffusion-controlled solid-state reactions induced by pressure and temperature changes, keeping surface concentrations in equilibrium with the other coexisting mineral phases. The results indicate that the mantle, from which the lherzolite xenolith was derived, underwent isothermal decompression followed by a weak heating on a time scale of a few tenths of million years before the xenolith extraction. From the deduced compression and decompression histories, we hypothesize that the mantle beneath Aitutaki Island was once dragged down to a garnet-stable deep mantle region and brought up later by small-scale sublithospheric convection.</jats:p>

    DOI

    Scopus

    3
    Citation
    (Scopus)

  • Deformation mechanisms and fluid conditions of mélange shear zones associated with seamount subduction

    Madison Frank, Kohtaro Ujiie, Ginta Motohashi and Takayoshi Nagaya

    Progress in Earth and Planetary Science (PEPS)   11:34   1 - 17  2024.06  [Refereed]

    Authorship：Last author

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>Lithologic heterogeneity and the presence of fluids have been linked to seamount subduction and collocated with slow earthquakes. However, the deformation mechanisms and fluid conditions associated with seamount subduction remain poorly understood. The exhumed Chichibu accretionary complex on Amami-Oshima Island preserves mélange shear zones composed of mudstone-dominated mélange and basalt–limestone mélange deformed under sub-greenschist facies metamorphism. The mudstone-dominated mélange contains sandstone, siliceous mudstone, and basalt lenses in an illitic matrix. The basalt–limestone mélange contains micritic limestone and basalt lenses in a chloritic matrix derived from the mixing of limestone and basalt at the foot of a seamount. The basalt–limestone mélange overlies the mudstone-dominated mélange, possibly representing a submarine landslide from the seamount onto trench-fill terrigenous sediments. The asymmetric <jats:italic>S</jats:italic>–<jats:italic>C</jats:italic> fabrics in both mélanges show top-to-SE shear consistent with megathrust-related shear. Quartz-filled shear and extension veins in the mudstone-dominated mélange indicate brittle failure at near-lithostatic fluid pressure and low differential stress. Microstructural observations show that deformation in the mudstone-dominated mélange was accommodated by dislocation creep of quartz and combined quartz pressure solution with frictional sliding of illite, whereas the basalt-limestone mélange was accommodated by frictional sliding of chlorite and dislocation creep of coarse-grained calcite, with possible pressure solution creep and diffusion creep of fine-grained calcite. The mélange shear zones formed in association with seamount subduction record temporal changes in deformation mechanisms, fluid pressure, and stress state during megathrust shear with brittle failure under elevated fluid pressure, potentially linking tremor generation near subducting seamounts.</jats:p>

    DOI

    Scopus

  • Deformation-induced, retrograde transformation of kyanite to andalusite: An example of felsic granulite in the southern Bohemian Massif

    Takuro Yoshioka, Kyuichi Kanagawa, Yoshikuni Hiroi, Takao Hirajima, Martin Svojtka, Tomokazu Hokada, Simon R. Wallis, Takayoshi Nagaya, Akira Miyake

    Tectonophysics   ( 877:230293 )  2024.04  [Refereed]

    DOI

    Scopus

    1
    Citation
    (Scopus)

  • Ultramafic Rocks from the Sanbagawa Belt: Records of Mantle Wedge Processes

    Atsushi Okamoto, Takayoshi Nagaya, Shunsuke Endo, and Tomoyuki Mizukami

    Elements   ( 20 ) 83 - 88  2024.04  [Refereed]

    　View Summary

    <jats:p>Mantle wedge domains beneath the forearc Moho are unique regions of Earth’s interior where mantle encounters subducting oceanic plates. Crystal-plastic deformation and fluid-induced reactions in the supra-subduction mantle control global material circulation, arc volcanism, and seismicity within subduction zones. The Sanbagawa metamorphic belt contains numerous ultramafic blocks in its higher-grade zones, some of which likely originated as lower crustal arc cumulates that were subsequently incorporated into the mantle wedge and transported to the slab–mantle interface by mantle flow. Properties of these ultramafic rocks provide a valuable opportunity to understand the dynamic processes of the mantle wedge up to 80 km depth, including mantle flow, hydration/dehydration, and fluid–rock interactions near the slab–mantle interface of a warm subduction zone.</jats:p>

    DOI

    Scopus

    10
    Citation
    (Scopus)

  • Mineralogical aspects of asteriscus of goldfish (Carassius auratus) consisting of vaterite

    Gen TAKAHASHI , Taiga OKUMURA, Takayoshi NAGAYA, Michio SUZUKI, Toshihiro KOGURE

    Journal of Mineralogical and Petrological Sciences (JMPS)   ( 119:231206 )  2024.03  [Refereed]

    DOI

    Scopus

    4
    Citation
    (Scopus)

  • Duplex Underplating, Sediment Dehydration and Quartz Vein Mineralization in the Deep Tremor Source Region

    Kohtaro Ujiie, Naoki Nishiyama, Hisaki Yamamoto, Minoru Yamashita, Takayoshi Nagaya, Takashi Sano, Yui Kouketsu

    Journal of Geophysical Research (JGR): Solid Earth   ( 129:e2023JB027901 )  2024.02  [Refereed]

    DOI

    Scopus

    10
    Citation
    (Scopus)

  • Subduction plate interface shear stress associated with rapid subduction at deep slow earthquake depths: example from the Sanbagawa belt, southwestern Japan

    Koyama, Y., Wallis, S. R., & Nagaya T

    Solid Earth   ( 15 ) 143 - 166  2024.02  [Refereed]

    Authorship：Last author

    　View Summary

    <jats:p>Abstract. Maximum shear stress along an active deformation zone marking the subduction plate interface is important for understanding earthquake phenomena and is an important input parameter in subduction zone thermomechanical modeling. However, such maximum shear stress is difficult to measure directly at depths more than a few kilometers and is generally estimated by simulation using a range of input parameters with large associated uncertainties. In addition, estimated values generally represent maximum shear stress conditions over short observation timescales, which may not be directly applicable to long-timescale subduction zone modeling. Rocks originally located deep in subduction zones can record information about deformation processes, including maximum shear stress conditions, occurring in regions that cannot be directly accessed. The estimated maximum shear stress is likely to be representative of maximum shear stress experienced over geological timescales and be suitable to use in subduction zone modeling over timescales of millions to tens of millions of years. In this study, we estimated maximum shear stress along a subduction plate interface by using samples from the Sanbagawa metamorphic belt of southwestern (SW) Japan, in which slivers of mantle-wedge-derived serpentinite are widely distributed and in direct contact with metasedimentary rocks derived from the subducted oceanic plate. These areas can be related to the zone of active deformation along the subduction plate interface. To obtain estimates of maximum shear stress at the subduction interface, we focused on the microstructure of quartz-rich metamorphic rocks – quartz is the main component of the rocks we collected and its deformation stress is assumed to be roughly representative of the stress experienced by the surrounding rock and plate interface deformation zone. Maximum shear stress was calculated by applying deformation temperatures estimated by the crystallographic orientation of quartz (the quartz c-axis fabric opening-angle thermometer) and the apparent grain size of dynamically recrystallized quartz in a thin section to an appropriate piezometer. Combined with information on sample deformation depth, estimated from the P–T (pressure–temperature) path and deformation temperatures, it is suggested that there was nearly constant maximum shear stress of 15–41 MPa in the depth range of about 15–30 km, assuming plane stress conditions even when uncertainties related to the measurement direction of thin section and piezometer differences are included. The Sanbagawa belt formed in a warm subduction zone. Deep slow earthquakes are commonly observed in modern-day warm subduction zones such as SW Japan, which has a similar thermal structure to the Sanbagawa belt. In addition, deep slow earthquakes are commonly observed to be concentrated in a domain under the shallow part of the mantle wedge. Samples showed the depth conditions near the mantle wedge, suggesting that these samples were formed in a region with features similar to the deep slow earthquake domain. Estimated maximum shear stress may not only be useful for long-timescale subduction zone modeling but also represent the initial conditions from which slow earthquakes in the same domain nucleated.
    </jats:p>

    DOI

    Scopus

    5
    Citation
    (Scopus)

  • Dehydration of brucite + antigorite under mantle wedge conditions: insights from the direct comparison of microstructures before and after experiments

    Nagaya,T., Okamoto, A., Kido, M., Muto, J., & Wallis, S. R.

    Contributions to Mineralogy and Petrology (CMP)   177:87  2022.09  [Refereed]  [International journal]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    13
    Citation
    (Scopus)

  • Multi-stage infiltration of Na- and K-rich fluids from pegmatites at mid-crustal depths as revealed by feldspar replacement textures

    Astin Nurdiana, Atsushi Okamoto, Kenta Yoshida, Masaoki Uno, Takayoshi Nagaya, Noriyoshi Tsuchiya

    Lithos   ( 388-389:106096 )  2021.05  [Refereed]  [International journal]

    DOI

    Scopus

    8
    Citation
    (Scopus)

  • Thermal structure in subducted units from continental Moho depths in a palaeo subduction zone, the Asemigawa region of the Sanbagawa metamorphic belt, SW Japan

    Yui Kouketsu, Kazushi Sadamoto, Hayato Umeda, Hirokazu Kawahara, Takayoshi Nagaya, Tomoki Taguchi, Hiroshi Mori, Simon Wallis, Masaki ENAMI

    Journal of Metamorphic Geology    2021  [Refereed]

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>Raman CM geothermometry applied to 126 samples of pelitic schists collected over an area of 11 km × 7 km reveals the thermal structure of the Asemigawa region of the Sanbagawa metamorphic belt, southwest Japan in unprecedented detail. In general, the estimated temperatures gradually increase from south to north in the range of 288–553°C. However, a temperature gap from ~380 to ~440°C is identified near the boundary between the chlorite and garnet zones. This temperature region matches the depth of the continental Moho of the Sanbagawa subduction zone. The temperature gradient in the higher‐temperature domain is higher than that in the lower‐temperature domain, and large‐scale tight folds that affect the thermal structure are developed in the high‐grade units and in the vicinity of the temperature discontinuity. These geological structures probably reflect that the exhumed slab units was dammed at the Moho depth due to the upward movement being impeded by increase in the coupling strength of the overlying rocks associated with exhumation from beneath serpentinite rocks to a shallower domain overlain by crustal rocks. Changes in the coupling strength along the subduction boundary led the strong folding at the higher‐temperature domain and the pre‐formed foliation developed at the Moho depth may have acted as the tectonic boundary, resulting in a temperature discontinuity. These results will contribute to elucidating various geological phenomena occurring in the forearc regions of modern subduction zones.</jats:p>

    DOI

    Scopus

    21
    Citation
    (Scopus)

  • Rapid fluid infiltration and permeability enhancement during middle-lower crustal fracturing: Evidence from amphibolite-granulite- facies fluid-rock reaction zones, Sør Rondane Mountains, East Antarctica

    Diana Mindaleva, Masaoki Uno, Fumiko Higashino, Takayoshi Nagaya, Atsushi Okamoto, Noriyoshi Tsuchiya

    Lithos   372-373:105521  2020.11  [Refereed]  [International journal]

    DOI

    Scopus

    24
    Citation
    (Scopus)

  • Crystallographic preferred orientation of talc determined by an improved EBSD procedure for sheet silicates: Implications for anisotropy at the slab–mantle interface due to Si-metasomatism

    Takayoshi Nagaya, Atsushi Okamoto, Ryosuke Oyanagi, Yusuke Seto, Akira Miyake, Masaoki Uno, Jun Muto, Simon R. Wallis

    American Mineralogist    2020.06  [Refereed]

    Authorship：Lead author, Corresponding author

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>Talc is widely distributed over the Earth's surface and is predicted to be formed in various tectonic settings. Talc is a very soft and anisotropic sheet silicate showing very low friction behavior. Therefore, the formation of talc is expected to weaken the strength of talc-bearing rocks and may be associated with the initiation of subduction, and with a decrease in the coupling coefficient resulting in aseismic movements along faults and shear zones within subduction zones. For these reasons, understanding the crystallographic preferred orientation (CPO) of talc is important to quantify the anisotropy and physical properties of the host rock. However, it is difficult to measure a significant number of talc crystal orientations and to evaluate the accuracy of the measurements using electron-backscattered diffraction (EBSD). Therefore, talc CPO has not been reported, and there is uncertainty regarding the estimation of the strength of deformed talc-bearing rocks. Using methods developed for antigorite, we report the first successful EBSD measurements of talc CPO from a talc schist formed due to Simetasomatism of ultramafic rocks by subduction zone fluids. We used a combination of W-SEM and FE-SEM measurements to examine domains of various grain sizes of talc. In addition, we used TEM measurements to evaluate the accuracy of the EBSD measurements and discuss the results of talc CPO analysis. Talc CPO in the present study shows a strong concentration of the pole to the (001) plane normal to the foliation. The strongest concentration of the [100] direction is parallel to the lineation. The talc schist produces similar S-wave splitting and P- and S-wave anisotropy as antigorite schist in deeper domains, thus identifying talc-rich layers in subduction zones may require a combination of geophysical surveys, seismic observations, and anisotropy modeling. The presence of strong talc CPO in rocks comprising the slab–mantle interface boundary may promote spatial expansion of the slip area during earthquakes along the base of the mantle wedge.</jats:p>

    DOI

    Scopus

    18
    Citation
    (Scopus)

  • Formation of secondary olivine after orthopyroxene during hydration of mantle wedge: evidence from the Khantaishir Ophiolite, western Mongolia

    Otgonbayar Dandar, Atsushi Okamoto, Masaoki Uno, Ryosuke Oyanagi, Takayoshi Nagaya, Ulziiburen Burenjargal, Tsuyoshi Miyamoto, Noriyoshi Tsuchiya

    Contributions to Mineralogy and Petrology (CMP)   174:86  2019.10  [Refereed]  [International journal]

    DOI

    Scopus

    20
    Citation
    (Scopus)

  • Coexisting different types of zoned garnet in kyanite-quartz eclogites from the Sanbagawa metamorphic belt: Evidence of deformation-induced lithological mixing during prograde metamorphism

    Masaki Enami, Jun-Ichi Kimura, Motohiro Tsuboi, Yui Kouketsu, Takayoshi Nagaya, Shuaimin Huang

    Island Arc   28:e12274  2019  [Refereed]  [International journal]

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>Garnet grains in Sanbagawa quartz eclogites from the Besshi region, central Shikoku commonly show a zoning pattern consisting of core and mantle/rim that formed during two prograde stages of eclogite and subsequent epidote–amphibolite facies metamorphism, respectively. Garnet grains in the quartz eclogites are grouped into four types (I, II, III, and IV) according to the compositional trends of their cores. Type I garnet is most common and sometimes coexists with other types of garnet in a thin section. Type I core formed with epidote and kyanite during the prograde eclogite facies stage. The inner cores of types II and III crystallized within different whole‐rock compositions of epidote‐free and kyanite‐bearing eclogite and epidote‐ and kyanite‐free eclogite at the earlier prograde stage, respectively. The inner core of type IV probably formed during the pre‐eclogite facies stage. The inner cores of types II, III, and IV, which formed under different P–T conditions of prograde metamorphism and/or whole‐rock compositions, were juxtaposed with the core of type I, probably due to tectonic mixing of rocks at various points during the prograde eclogite facies stage. After these processes, they have shared the following same growth history: (i) successive crystal growth during the later stage of prograde eclogite facies metamorphism that formed the margin of the type I core and the outer cores of types II, III, and IV; (ii) partial resorption of the core during exhumation and hydration stage; and (iii) subsequent formation of mantle zones during prograde metamorphism of the epidote–amphibolite facies. The prograde metamorphic reactions may not have progressed under an isochemical condition in some Sanbagawa metamorphic rocks, at least at the hand specimen scale. This interpretation suggests that, in some cases, material interaction promoted by mechanical mixing and fluid‐assisted diffusive mass transfer probably influences mineral reactions and paragenesis of high‐pressure metamorphic rocks.</jats:p>

    DOI

    Scopus

    3
    Citation
    (Scopus)

  • Minimizing and quantifying mis-indexing in electron backscatter diffraction (EBSD) determinations of antigorite crystal directions

    Takayoshi Nagaya, Simon R. Wallis, Yusuke Seto, Akira Miyake, Yusuke Soda, Seiichiro Uehara, Megumi Matsumoto

    Journal of Structural Geology    2017.02  [Refereed]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    20
    Citation
    (Scopus)

  • An integrated EPMA-EBSD study of metamorphic histories recorded in garnet

    Masaki Enami, Takayoshi Nagaya, Maw Maw Win

    American Mineralogist    2017.01  [Refereed]

    DOI

    Scopus

    12
    Citation
    (Scopus)

  • Seismic evidence for flow in the hydrated mantle wedge of the Ryukyu subduction zone

    Takayoshi Nagaya, Andrew M. Walker, James Wookey, Simon R. Wallis, Kazuhiko Ishii, J. -Michael Kendall

    Scientific Reports    2016.07  [Refereed]

    Authorship：Lead author, Corresponding author

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>It is widely accepted that water-rich serpentinite domains are commonly present in the mantle above shallow subducting slabs and play key roles in controlling the geochemical cycling and physical properties of subduction zones. Thermal and petrological models show the dominant serpentine mineral is antigorite. However, there is no good consensus on the amount, distribution and alignment of this mineral. Seismic velocities are commonly used to identify antigorite-rich domains, but antigorite is highly-anisotropic and depending on the seismic ray path, its properties can be very difficult to distinguish from non-hydrated olivine-rich mantle. Here, we utilize this anisotropy and show how an analysis of seismic anisotropy that incorporates measured ray path geometries in the Ryukyu arc can constrain the distribution, orientation and amount of antigorite. We find more than 54% of the wedge must consist of antigorite and the alignment must change from vertically aligned to parallel to the slab. This orientation change suggests convective flow in the hydrated forearc mantle. Shear wave splitting analysis in other subduction zones indicates large-scale serpentinization and forearc mantle convection are likely to be more widespread than generally recognized. The view that the forearc mantle of cold subduction zones is dry needs to be reassessed.</jats:p>

    DOI

    Scopus

    39
    Citation
    (Scopus)

  • Brucite as an important phase of the shallow mantle wedge: Evidence from the Shiraga unit of the Sanbagawa subduction zone, SW Japan

    Hirokazu Kawahara, Shunsuke Endo, Simon R. Wallis, Takayoshi Nagaya, Hiroshi Mori, Yoshihiro Asahara

    Lithos    2016.06  [Refereed]

    DOI

    Scopus

    35
    Citation
    (Scopus)

  • Phase equilibria modelling of blueschist and eclogite from the Sanbagawa metamorphic belt of southwest Japan reveals along‐strike consistency in tectonothermal architecture

    O. M. Weller, S. R. Wallis, M. Aoya, T. Nagaya

    Journal of Metamorphic Geology    2015.08  [Refereed]

    Authorship：Last author

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>The Sanbagawa metamorphic belt of southwest Japan is one of the type localities of subduction‐related high‐<jats:italic>P</jats:italic> metamorphism. However, variable pressure–temperature (<jats:italic>P</jats:italic>–<jats:italic>T</jats:italic>) paths and metabasic assemblages have been reported for eclogite units in the region, leading to uncertainty about the subduction zone paleo‐thermal structure and associated tectonometamorphic conditions. To analyse this variation, phase equilibria modelling was applied to the three main high‐<jats:italic>P</jats:italic> metabasic rock types documented in the region – glaucophane eclogite, barroisite eclogite and garnet blueschist – with modelling performed over a range of <jats:italic>P</jats:italic>,<jats:italic> T</jats:italic>, bulk rock H<jats:sub>2</jats:sub>O and bulk rock ferric iron conditions using <jats:sc>thermocalc</jats:sc>. All samples are calculated to share a common steep prograde <jats:italic>P</jats:italic>–<jats:italic>T</jats:italic> path to similar peak conditions of ∼16–20 kbar and 560–610 °C. The results establish that regional assemblage variation is systematic, with the alternation in peak amphibole phase due to peak conditions overlapping the glaucophane–barroisite solvus, and bulk composition effects stabilizing blueschist <jats:italic>v</jats:italic>. eclogite facies assemblages at similar <jats:italic>P</jats:italic>–<jats:italic>T</jats:italic> conditions. Furthermore, the results reveal that a steep prograde <jats:italic>P</jats:italic>–<jats:italic>T</jats:italic> path is common to all eclogite units in the Sanbagawa belt, indicating that metamorphic conditions were consistent along strike. All localities are compatible with predictions made by a ridge approach model, which attributes eclogite facies metamorphism and exhumation of the Sanbagawa belt to the approach of a spreading ridge.</jats:p>

    DOI

    Scopus

    25
    Citation
    (Scopus)

  • Reply to comment by Nozaka (2014) on "Dehydration breakdown of antigorite and the formation of B-type olivine CPO"

    Takayoshi Nagaya, Simon R. Wallis, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami, Yusuke Seto, Akira Miyake, Megumi Matsumoto

    Earth and Planetary Science Letters (EPSL)   408   406 - 407  2014.12  [Refereed]  [International journal]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    1
    Citation
    (Scopus)

  • Two types of antigorite serpentinite controlling heterogeneous slow-slip behaviours of slab–mantle interface

    Tomoyuki Mizukami, Hironori Yokoyama, Yoshihiro Hiramatsu, Shoji Arai, Hirokazu Kawahara, Takayoshi Nagaya, Simon R. Wallis

    Earth and Planetary Science Letters    2014.09  [Refereed]

    DOI

    Scopus

    28
    Citation
    (Scopus)

  • Dehydration breakdown of antigorite and the formation of B-type olivine CPO

    Takayoshi Nagaya, Simon R. Wallis, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami, Yusuke Seto, Akira Miyake, Megumi Matsumoto

    Earth and Planetary Science Letters    2014.02  [Refereed]

    Authorship：Lead author, Corresponding author

    DOI

    Scopus

    46
    Citation
    (Scopus)

▼display all

Presentations

  • Noble gas and halogen contents and source of fluid along the slab-mantle interface: Example of the Shiraga serpentinite body, the Cretaceous Sanbagawa metamorphic belt, SW Japan

    Koki Aida, Ren Jie, Simon Wallis, Hirochika Sumino, Yui Kouketsu, Takayoshi Nagaya

    JpGU-AGU JOINT MEETING 2026 

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • Ultramafic rocks as preferential fluid pathways during high-temperature dehydration: Evidence from a contact metamorphic aureole in the Sanbagawa Belt, central Japan

    Kaho Nobuhara, Hiroshi Mori, Yurie Tsukishima, Takayoshi Nagaya, Ken Yamaoka, Koichiro Fujimoto, Tetsuya Tokiwa, Takashi Shinya, Yuho Hayakawa

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • Potential geological records of deep slow earthquakes: the view from the Sanbagawa metamorphic belt

    Yukinojo Koyama, Simon Richard Wallis, Takayoshi Nagaya, Mutsuki Aoya

    JpGU-AGU JOINT MEETING 2026 

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • Magnetization-based mapping of serpentinite bodies using drone-borne aeromagnetic surveys: a case study from the Sanbagawa Belt

    Nanami Kuniya, Hiroshi Mori, Ryuta Shukuwa, Yuto Yasui, Kaho Nobuhara, Shigeo Okuma, Ayumu Miyakawa, Tetsuya Tokiwa, Kazuhiro Ozawa, Ken Yamaoka, Takayoshi Nagaya, Daichi Murakami

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • Deep deformation environment at the 25°S OCC inferred from phlogopite-bearing peridotite

    Y. Soda, T. Nagaya, T. Sawaguchi, T. Mizukami, T. Morishita, H. Kumagai, S. Wallis

    JpGU-AGU JOINT MEETING 2026 

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • Formation Process and Timing of Type I Feather Features in Shocked Quartz

    Toshihiro Tada, Auriol Rae, Hiroshi Sakuma, Naotaka Tomioka, Takayoshi Nagaya, Kosuke Kurosawa

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • A shock recovery method using decaying shock waves and Its application to Earth and planetary materials

    Kosuke Kurosawa, Takafumi Niihara, Haruka Oono, Christopher Hamann, Toshihiro Tada, Takayoshi Nagaya, Hidenori Genda, Naotaka Tomioka

    JpGU-AGU JOINT MEETING 2026 

    Presentation date： 2026.05

    Event date：
    2026.05
    　
    　

  • 方解石砂への衝突実験

    黒澤耕介、富岡尚敬、永冶方敬、佐藤雅彦、大野遼、新原隆史、長谷川直

    令和7年度 宇宙科学に関する室内実験シンポジウム 

    Event date：
    2026.02
    　
    　

  • Coseismic recrystallization of calcite at shallow depths: insights from the active Yonabaru Fault, Miyako Island, southern Ryukyu Arc

    Thomas Yeo, Kohtaro Ujiie, Kaoru Inoue, Takayoshi Nagaya, Ken-ichi Hirauchi

    12th ACES (APEC Cooperation for Earthquake Science) International Workshop 

    Presentation date： 2025.11

    Event date：
    2025.11
    　
    　

  • Practical Protocol for Quartz c-Axis Opening-Angle Thermometry Using EBSD Measurements

    Yukinojo Koyama, Simon R. Wallis, Takayoshi Nagaya, Mutsuki Aoya

    GSA (the Geological Society of America) Connects 2025 

    Presentation date： 2025.10

    Event date：
    2025.10
    　
    　

  • The relationship between rock structures showing simultaneous brittle and ductile deformation and slow earthquakes: the view from the Sanbagawa belt

    Yukinojo Koyama, Simon R. Wallis, Takayoshi Nagaya, Mutsuki Aoya

    International Joint Workshop on Slow-to-Fast Earthquakes 2025 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • Co-seismic ductile deformation in carbonate-hosted active faults

    Thomas Yeo, Kohtaro Ujiie, Kaoru Inoue, Takayoshi Nagaya, Hirauchi Ken-ichi

    International Joint Workshop on Slow-to-Fast Earthquakes 2025 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • Co-seismic ductile deformation in carbonate-hosted active faults

    Thomas Yeo, Kohtaro Ujiie, Kaoru Inoue, Takayoshi Nagaya, Hirauchi Ken-ichi

    日本地質学会 第132年学術大会 (2025年熊本大会) 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • ドローン磁気探査による蛇紋岩分布の抽出：赤石山地北部・三波川帯の例

    國谷 七海、森 宏、宿輪 隆太、安井 悠人、延原 香穂、大熊 茂雄、宮川 歩夢、常盤 哲也、小澤 和浩、山岡健、永冶 方敬、村上 大知

    日本地質学会 第132年学術大会 (2025年熊本大会) 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • 接触変成作用に伴う超苦鉄質岩類の熱変成反応と流体活動：赤石山地北部・三波川帯の例

    延原香穂、森宏、築島由理恵、永冶方敬、新屋貴史、早川由帆、山岡健、原英俊、藤本光一郎、常盤哲也

    日本地質学会 第132年学術大会 (2025年熊本大会) 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • 分子動力学計算によるブルーサイト/オリビン界面のトポタキシーの検討

    清水 光希、川野 潤、永冶 方敬、永井 隆哉、ウォリス サイモン

    日本鉱物科学会 2025年度年会 

    Presentation date： 2025.09

    Event date：
    2025.09
    　
    　

  • DISLOCATION MICROSTRUCTURES IN EXPERIMENTALLY SHOCKED CALCITE: COMPARISON WITH CALCITE IN AN ASTEROID RYUGU PARTICLE

    N. Tomioka, K. Kurosawa, A. Miyake, Y. Igami, T. Nagaya, T. Noguchi, T. Matsumoto, M. Miyahara, Y. Seto

    Meeting of the International Meteoritical Society 2025 (MetSoc2025) 

    Presentation date： 2025.07

    Event date：
    2025.07
    　
    　

  • 接触変成域・超苦鉄質岩類中の変成反応と流体挙動：長野県伊那地域・三波川帯の例

    延原香穂、森宏、築島由理恵、永冶方敬、新屋貴史、早川由帆、山岡健

    日本地質学会中部支部 2025年支部年会 研究発表会 

    Presentation date： 2025.06

    Event date：
    2025.06
    　
    　

  • Co-seismic ductile deformation in the carbonate-hosted active faul

    Thomas Yeo, Kohtaro Ujiie, Kaoru Inoue, Takayoshi Nagaya

    Japan Geoscience Union Meeting 2025 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • カルサイトの衝撃変形における転位組織変化

    富岡 尚敬、黒澤 耕介、三宅 亮、伊神 洋平、永冶 方敬、野口 高明、松本 徹、宮原 正明、瀬戸 雄介  [Invited]

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • Constructing CPO patterns from EBSD measurements to be used in quartz c-axis fabric opening-angle thermometry: issues and proposed protocol

    小山 雪乃丞、ウォリス サイモン、永冶 方敬、青矢 睦月

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • 低温でのドロマイトの延性変形：東アルプスの例

    髙畑 彩、ウォリス サイモン、永冶 方敬、小山 雪乃丞

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • 脱蛇紋岩化反応で生じるブルーサイト/オリビン界面の理論的解析：分子動力学計算からの検討

    清水 光希、川野 潤、永冶 方敬、永井 隆哉、ウォリス サイモン

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • 接触変成域・超苦鉄質岩類の変成反応解析に基づく流体挙動の追跡：赤石山地北部・三波川帯の例

    延原 香穂、築島 由理恵、森 宏、永冶 方敬、新屋 貴史、早川 由帆、山岡 健

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • 方解石砂への高速度衝突: 衝突点近傍の圧力分布

    黒澤 耕介、富岡 尚敬、永冶 方敬、佐藤 雅彦、大野 遼、新原 隆史、長谷川 直

    日本地球惑星科学連合2025年大会 

    Presentation date： 2025.05

    Event date：
    2025.05
    　
    　

  • 動的再結晶粒子の選別と等高線作成方法を考慮した石英c軸ファブリックの構築: 変形温度の推定に与える影響について

    小山 雪乃丞、ウォリス サイモン、永冶 方敬、青矢 睦月

    変成岩などシンポジウム  (青葉山キャンパス (東北大学)) 

    Presentation date： 2025.03

    Event date：
    2025.03
    　
    　

  • 深部流体挙動の把握に向けた接触変成域•超苦鉄質岩類の変成反応解析: 赤石山地北部•三波川帯の例

    延原香穂、築島由理恵、森宏、永冶方敬、新屋貴史、早川由帆、山岡健

    変成岩などシンポジウム  (青葉山キャンパス (東北大学)) 

    Presentation date： 2025.03

    Event date：
    2025.03
    　
    　

  • 方解石砂を用いた完全解放系衝撃回収実験

    黒澤耕介、冨岡尚敬、永冶方敬、佐藤雅彦、大野遼、新原隆史、長谷川直

    宇宙科学に関する室内実験シンポジウム  (オンライン) 

    Presentation date： 2025.02

    Event date：
    2025.02
    　
    　

  • EBSDによるコーサイト―石英相転移の検証～三波川帯権現地域の例～

    箕輪 桃子、永冶 方敬、伊藤 泰輔、ウォリス サイモン

    日本地質学会第131年学術大会 

    Presentation date： 2024.09

  • 沈み込み帯プレート境界にかかる最大剪断応力の推定と沈み込み帯熱モデルの再検討：後期白亜紀, 三波川沈み込み帯の例

    小山雪乃丞、ウォリス サイモン、永冶方敬、青矢睦月

    日本地質学会第131年学術大会 

    Presentation date： 2024.09

  • 「コーサイト相転移石英のEBSD検出法」の確立に向けて—西南日本四国三波川変成帯権現地域の組み込み—」

    箕輪 桃子、永冶 方敬、伊藤 泰輔、ウォリス サイモン

    日本鉱物科学会2024年年会  (名古屋大学 東山キャンパス) 

    Presentation date： 2024.09

  • 長野県伊那地域を例とした，三波川帯低変成度域に分布する超苦鉄質岩類の岩石学的記載

    延原 香穂、森 宏、永冶 方敬

    日本鉱物科学会2024年年会  (名古屋大学 東山キャンパス) 

    Presentation date： 2024.09

  • Deformation mechanisms and stress along the plate interface at depths of deep slow earthquakes: the view from the Sanbagawa belt

    Yukinojo Koyama, Simon R. Wallis, Takayoshi Nagaya, and Mutsuki Aoya

    International Joint Workshop on Slow-to-Fast Earthquakes 2024  (Oita, Japan)  Science of Slow-to-Fast Earthquakes

    Presentation date： 2024.09

  • Duplex Underplating, Sediment Dehydration and Quartz Vein Mineralization in the Deep Tremor Source Region

    Kohtaro Ujiie, Naoki Nishiyama, Hisaki Yamamoto, Minoru Yamashita, Takayoshi Nagaya, Takashi Sano, Yui Kouketsu

    Japan Geoscience Union (JpGU) Meeting 2024 

    Presentation date： 2024.05

  • Detailed Occurrence of Feather Features in Quartz in Experimentally Shocked Granite

    japan Geoscience Union (JpGU) Meeting 2024 

    Presentation date： 2024.05

  • Estimation of emplacement pressure of plutonic rocks around the Itoigawa–Shizuoka Tectonic Line and reconstruction of geological distribution before the fault movement

    japan Geoscience Union (JpGU) Meeting 2024 

    Presentation date： 2024.05

  • Shear heating along subduction zones and thermal structure in the domain of deep slow earthquakes: evidence from the exhumed subduction-type Sanbagawa metamorphic belt, SW Japan

    Simon R. Wallis, Kazuhiko Ishii, Yukinojo Koyama, and Takayoshi Nagaya

    EGU2024  (Vienna, Austria) 

    Presentation date： 2024.04

  • Microstructure, deformation mechanisms and stress along the plate interface: the view from the Sanbagawa belt

    Yukinojo Koyama, Simon R. Wallis, Takayoshi Nagaya

    変成岩などシンポジウム2024 

    Presentation date： 2024.03

  • Duplex Underplating, Sediment Dehydration and Quartz Vein Mineralization in the Deep Tremor Source Region

    Kohtaro Ujiie, Naoki Nishiyama, Hisaki Yamamoto, Minoru Yamashita, Takayoshi Nagaya, Takashi Sano, Yui Kouketsu

    American Geophysical Union2023  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2023.12

  • 衝撃回収実験により形成された、⽯英中のFeather Features の特徴

    多田 賢弘, 黒澤 耕介, 富岡 尚敬, 永冶 方敬, 伊佐 純子, Christopher Hamann, 大野 遼, 新原 隆史, 岡本 尚也, 松井 孝典

    ⽇本惑星科学会 2023 年秋季講演会 

    Presentation date： 2023.10

  • Serpentinization and Contact metamorphism processes based on spatial variation of mineral combinations in ultramafic rocks of the Sanbagawa Belt, Ina area, Nagano Prefecture, Japan

    The 130th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2023.09

  • Subduction plate interface shear stress distribution and its time evolution at deep slow earthquake depths: example from the Sanbagawa belt, Southwest Japan

    The 130th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2023.09

  • B-type antigorite crystal preferred orientation (CPO) by grain boundary sliding from Sanbagawa belt, Shikoku, Japan: implications for the distribution of antigorite CPO patterns in subduction zones

    Takayoshi Nagaya, Simon R. Wallis, Ryosuke Ando

    WaterRock Interaction（WRI17）  (Sendai, Japan) 

    Presentation date： 2023.08

  • Deformation mechanisms and rheology of mélange shear zones associated with seamount subduction

    Madison Frank, Kohtaro Ujiie, Ginta Motohashi, Takayoshi Nagaya

    WaterRock Interaction（WRI17）  (Sendai, Japan) 

    Presentation date： 2023.08

  • Deformation mechanisms and rheology of melange shear zones associated with seamount subduction

    Frank Madison, Ujiie Kohtaro, Motohashi Ginta, Nagaya Takayoshi

    Slow-to-Fast earthquake workshop in Taiwan  (Taiwan) 

    Presentation date： 2023.03

  • 魚類耳石を構成するvateriteの結晶学的特徴

    高橋玄, 奥村大河, 永冶方敬, 鈴木道生, 小暮敏博

    第17回バイオミネラリゼーションワークショップ 

    Presentation date： 2022.11

  • Nature of the plate boundary domain at the depth of deep slow earthquakes: evidence from the Sanbagawa belt

    The 129th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2022.09

  • Petrological characteristics and their spatial variations of the Ryoke mylonitic rocks nearby the Median Tectonic Line in central Kii Peninsula, SW Japan

    The 129th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2022.09

  • Crystallographic characteristics of vaterite in fish otolith

    JAMS 2022 Annual Meeting 

    Presentation date： 2022.09

  • Geological characteristics and stress distribution in deep slow earthquake domain: evidence from the subduction-type Sanbagawa metamorphic belt

    Yukinojo Koyama, Simon Richard Wallis, Takayoshi Nagaya

    Japan Geoscience Union Meeting 2022  (Chiba) 

    Presentation date： 2022.06

  • Deformation temperature and strain rate estimations for Mie mélange of Nagasaki Metamorphic Rocks

    Seiya Maehara, Ryosuke Ando, Takayoshi Nagaya, Kohtaro Ujiie, Simon Richard Wallis, Koyama Yukinojo

    Japan Geoscience Union Meeting 2022  (Chiba) 

    Presentation date： 2022.06

  • Antigorite grain boundary sliding accommodated by micro-cracking and dissolution-precipitation creep in subduction zone

    Takayoshi Nagaya, Simon Richard Wallis

    Japan Geoscience Union Meeting 2022  (Chiba) 

    Presentation date： 2022.06

  • Deformation-induced transformation of kyanite to andalusite: An example of Gföhl granulite in the southern Bohemian Massif

    Japan Geoscience Union Meeting 2022 

    Presentation date： 2022.05

  • Unraveling the primitive W isotope compositions of kimberlites

    Otaro Kobayashi, Shiki Machida, Takayoshi Nagaya, Ichiro Kaneoka, Tsuyoshi Iizuka

    Japan Geoscience Union Meeting 2022  Chiba

    Presentation date： 2022.05

  • Fingerprints of subducted noble gas and halogen in the Franciscan serpentinite, California

    Jie Ren, Hirochika Sumino, Simon Richard Wallis, Takayoshi Nagay

    Japan Geoscience Union Meeting 2022  (Chiba) 

    Presentation date： 2022.05

  • The Geological Fingerprints of Slow Earthquakes

    JAMS 2021 Annual Meeting 

    Presentation date： 2021.09

  • Antigorite deformation mechanism and coupling depth of shallow wedge mantle

    JAMS 2021 Annual Meeting 

    Presentation date： 2021.09

  • Evaluation of dynamics of crustal fracturing and fluid flow revealed by static and petro-equilibrium analyses

    Presentation date： 2021.09

  • Underplating of metapelite and metabasite at source depths of ETS

    Kohtaro Ujiie, Naoki Nishiyama, Minoru Yamashita, and Takayoshi Nagaya

    Slow Earthquakes WS 2021 

    Presentation date： 2021.09

  • Development of crystallographic preferred orientation during normal faulting in the Pleistocene Ryukyu Limestone

    井上郁, 氏家恒太郎, 永冶方敬

    日本地球惑星科学連合2021年大会 

    Presentation date： 2021.05

  • EBSD解析の新しい試み

    Wallis Simon, Takayoshi Nagaya, Kenta Yoshida, Ryosuke Oyanagi

    変成岩などシンポジウム2021 

    Presentation date： 2021.03

  • 宮古島与那原断層において見出された正断層運動時における動的再結晶

    井上郁・氏家恒太郎・永冶方敬

    東京大学大気海洋研共同利用研究集会「琉球弧ダイナミクスの新展開：島弧ダイナミクスの理解への新たな切り口」 

    Presentation date： 2021.03

  • Generation of porosity network in plagioclase induced by multistage infiltration of reactive fluids into metamorphic rocks around quartz diorite intrusion at the middle crust

    Astin Nurdiana, Atsushi Okamoto, Masaoki Uno, Kenta Yoshida, Takayoshi Nagaya, Noriyoshi Tsuchiya

    AGU Fall Meeting 2020 

    Presentation date： 2020.12

  • New approach to EBSD analysis(of ‘difficult’ geological materials)

    S. R. Wallis, T. Nagaya, Y. Seto, K. Yoshida, R. Oyanagi

    変成岩などシンポジウム2020 

    Presentation date： 2020.11

  • Wallis Simon;Takayoshi Nagaya;Kenta Yoshida;Ryosuke Oyanagi

    S. R. Wallis, T. Nagaya, Y. Seto, K. Yoshida, R. Oyanagi

    変成岩などシンポジウム2020 

    Presentation date： 2020.11

  • Micro- to nano-pores in feldspar alteration by multistage fluid propagation; an observation from pegmatite-related metamorphic rocks and hydrothermal experimental approach

    Astin Nurdiana, Atsushi Okamoto, Masaoki Uno, Kenta Yoshida, Takayoshi Nagaya, Noriyoshi Tsuchiya

    日本鉱物科学会2020 

    Presentation date： 2020.09

  • Thermal structure near the continental Moho of subduction zone: Natural example of the Asemigawa region of the Sanbagawa metamorphic belt, SW Japan

    Yui Kouketsu, Kazushi, Sadamoto, Hayato Umeda, Hirokazu Kawahara, Takayoshi Nagaya, Tomoki Taguchi, Hiroshi Mori, Simon Wallis, Masaki Enami

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Deformation of antigorite serpentinite in the base of the shallow wedge mantle and relationship to slow earthquakes

    Kazuyuki Yoshida, Takayoshi Nagaya, Simon Richard Walli

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • The formation of micro- to nano-pores in feldspars induced by fluid infiltration within the crust

    Astin Nurdiana, Atsushi Okamoto, Masaoki Uno, Kenta Yoshida, Takayoshi Nagaya, Noriyoshi Tsuchiya

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Crystal Preferred Orientation development of Secondary Olivine Formed by Hydration of Othopyroxene: Implication to Anisotropy of Shallow Mantle Wedge during Initiation Stage of Subduction

    Otgonbayar DANDAR, Atsushi OKAMOTO, Takayoshi NAGAYA, Masaoki UNO, Noriyoshi TSUCHIYA

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Serpentinized shear zones with low frictional strength by grain-boundary sliding of antigorite at the depth of deep SSEs

    Takayoshi Nagaya, Simon Richard Wallis

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Brucite as a major phase in the shallow mantle wedge

    Takayoshi Nagaya, Simon Richard Wallis, Kazuhiro Kawahara, Shunsuke Endo, Hiroshi Mori, Yoshihiro Asahara

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Mineralogy and structure of the shallow mantle wedge: evidence from seismic anisotropy in the Ryukyu Arc and structural petrological studies

    Takayoshi Nagaya, Simon Richard Wallis, Andrew Walker, James Wookey, Kazuhiko Ishii, Michael Kendall

    JpGU-AGU Joint Meeting 2020 

    Presentation date： 2020.07

  • Dynamic recrystallization of olivine under wet and high stress conditions

    The 126th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2019.09

  • Thermal and deformation structure of slab near the Moho discontinuity in the Asemigawa region of the Sanbagawa belt

    The 126th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2019.09

  • Generation and development of porosity networks in mantle wedge duringdehydration process of spatially non-uniform brucite and antigorite

    The 126th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2019.09

  • 沈み込み帯スラブーマントル境界における強いtalc CPOの形成

    永冶 方敬, 岡本 敦, 大柳 良介, 瀬戸雄介, 三宅亮, 宇野正起, 武藤潤, ウォリス サイモン

    変成岩などシンポジウム2019 

    Presentation date： 2019.03

  • Grain boundary sliding as an antigorite CPO formation mechanism and implications for the slab-mantle boundary rheology: Example of antigorite schist from the Sanbagawa belt, SW Japan

    Takayoshi Nagaya, Simon Wallis

    American Geophysical Union (AGU) Fall Meeting  (Washington, D.C., United States of America, the Walter E. Washington Convention Center) 

    Presentation date： 2018.12

  • Formation in antigorite schist from the Sanbagawa belt, SW Japan by grain boundary sliding

    Simon Wallis, Takayoshi Nagaya

    日本地質学会第125年学術大会 

    Presentation date： 2018.09

  • Recrystallization process of olivine in DisGBS regime: Detailed orientation analysis for neoblast formation

    The 125th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2018.09

  • Time scales of Cl-bearing fluid infiltration and permeability estimated by reactive transport modelling for granulite/amphibolite-hosted reaction zones, Sør Rondane Mountains, East Antarctica

    Diana Mindaleva, Masaoki Uno, Fumiko Higashino, Takayoshi Nagaya, Ryosuke Oyanagi, Atsushi Okamoto, Noriyoshi Tsuchiya

    Japan Geoscience Union Meeting 2018 

    Presentation date： 2018.05

  • Crystal Preferred Orientation of Secondary Olivine Formed after Orthopyroxene in Mantle Wedge during Serpentinization from the Khantaishir Ophiolite, Western Mongolia

    Otgonbayar DANDAR, Atsushi OKAMOTO, Takayoshi NAGAYA, Masaoki UNO, Noriyoshi TSUCHIYA

    Japan Geoscience Union Meeting 2018 

    Presentation date： 2018.05

  • Grain boundary sliding and antigorite CPO formation in antigorite schist from the Sanbagawa belt, SW Japan: implications for the slab–mantle boundary rheology

    Simon Richard Wallis, Takayoshi Nagaya

    Japan Geoscience Union Meeting 2018  (Makuhari Messe, Chiba, Japan) 

    Presentation date： 2018.05

  • Analysis of EBSD mapping data of antigorite schist from the Sanbagawa belt, SW Japan and implication of a grain boundary sliding as an antigorite CPO formation mechanism

    Takayoshi Nagaya, Simon Wallis

    European Geosciences Union (EGU) General Assembly 2018, Austria Center Vienna (ACV)  (Vienna, Austria) 

    Presentation date： 2018.04

  • Time scales of Cl-bearing fluid infiltration and permeability estimated by reactive transport modeling for ranulite/amphibolite-hosted reaction zones, southern Sør Rondane Mountains, East Antarctica

    Diana Mindaleva, Masaoki Uno, Fumiko Higashino, Takayoshi Nagaya, Ryosuke Oyanagi, Atsushi Okamoto, Noriyoshi Tsuchiya

    15th International Workshop on WATER DYNAMICS Deeper and Hotter in Frontier Earth  (Tohoku University, Miyagi, Japan) 

    Presentation date： 2018.03

  • Investigation of Mass Transport and Reactive Mechanism by Cl Bearing Fluid Infiltration during Multiple Hydration Events, Sør Rondane Mountains, East Antarctica

    Diana Mindaleva, Masaoki Uno, Atsushi Okamoto, Takayoshi Nagaya, Noriyoshi Tsuchiya

    第8回極域科学シンポジウム 

    Presentation date： 2017.12

  • Mass Transfer during Formation of Secondary Olivine within Subduction Zone: Example from the Khantaishir Ophiolite, Western Mongolia

    DANDAR Otgonbayar, OKAMOTO Atsushi, UNO Masaoki, NAGAYA Takayoshi, TSUCHIYA Noriyoshi

    日本地質学会 124 年学術大会  (愛媛) 

    Presentation date： 2017.09

  • Grain boundary sliding as an antigorite CPO formation mechanism

    Simon Wallis, Takayoshi Nagaya, Atsushi Okamoto, Seiichiro Uehara, Katsuyoshi Michibayashi, Aya Nishii

    Joint Workshop on Slow Earthquakes 2017  (Hotel Mystays Matsuyama, Matsuyama) 

    Presentation date： 2017.09

  • Nucleation of 10 micron-scale olivine grains in chlorite peridotite due to dynamic recrystallization

    Presentation date： 2017.09

  • The thermal structure of the Sanbagawa subduction zone estimated by Raman carbonaceous material geothermometry in the Shiraga region, central Shikoku

    The 124th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2017.09

  • Talc CPO formed by Si-metasomatism at the slab-mantle interfaces in subduction zones

    Presentation date： 2017.09

  • Direct comparative observations of the formation of olivine after the dehydration experiment of brucite and antigorite

    The 124th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2017.09

  • Chemically induced formation of pull-apart structure of Cr-spinel

    新井 翔, 水上 知行, 永冶 方敬, ウォリス サイモン, 森下 知晃, 曽田 祐介

    JpGU-AGU Joint Meeting 2017 

    Presentation date： 2017.05

  • Rheological transition during progressive antigorite serpentinization of peridotite

    Tsubasa Arai, Tomoyuki Mizukami, Takayoshi Nagaya, Simon Wallis

    JpGU-AGU Joint Meeting 2017 

    Presentation date： 2017.05

  • Petrological and structural analyses of ultrafine-grained ductile shear zone in hydrous peridotite: A case study of the Gongen outcrop in the Sanbagawa belt

    Miho Komai, Tomoyuki Mizukami, Tsubasa Arai, Takayoshi Nagaya, Simon Wallis

    JpGU-AGU Joint Meeting 2017  (Makuhari Messe, Chiba, Japan) 

    Presentation date： 2017.05

  • Evidence for localized high fluid pressure along the paleo subduction boundary exposed in the Sanbagawa belt, SW Japan

    Simon Wallis, Shunsuke Endo, Takayoshi Nagaya, Hiroshi Mori, Yoshihiro Asahara, Hirokazu Kawahara

    JpGU-AGU Joint Meeting 2017  (Makuhari Messe, Chiba, Japan) 

    Presentation date： 2017.05

  • Mis-indexing of antigorite crystallographic orientations in EBSD measurements

    Takayoshi Nagaya, Simon Wallis, Yusuke Seto, Akira Miyake, Yusuke Soda, Seiichiro Uehara, Megumi Matsumoto

    JpGU-AGU Joint Meeting 2017  (Makuhari Messe, Chiba, Japan) 

    Presentation date： 2017.05

  • Rheological transition during progressive antigorite serpentinization of peridotite

    新井翔, 水上知行, 永冶方敬, Simon Wallis

    変成岩などシンポジウム2017 

    Presentation date： 2017.03

  • 含水かんらん岩における極細粒延性剪断帯の構造岩石学：三波川帯権現越露頭の例

    駒井美穂, 水上知之, 新井翔, 永冶方敬, Wallis Simon

    変成岩などシンポジウム2017 

    Presentation date： 2017.03

  • Chemically driven formation of pull-apart structure of Cr-spinel

    新井翔, 水上知行, 永冶方敬, Simon Wallis, 森下知晃, 曽田祐介

    変成岩などシンポジウム2017 

    Presentation date： 2017.03

  • アンチゴライトの自動EBSDマッピング

    永冶 方敬, ウォリス サイモン, 瀬戸 雄介, 三宅 亮, 曽田 祐介, 上原 誠一郎, 松本 恵

    変成岩などシンポジウム2017 

    Presentation date： 2017.03

  • Mineralogy of the mantle wedge at depths of deep slow slip: implications for fluid flow along the subduction boundary

    Simon Wallis, Shunsuke Endo, Takayoshi Nagaya, Hirokazu Kawahara, Hiroshi Mori, Yoshihiro Asahara

    American Geophysical Union (AGU) Fall Meeting  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2016.12

  • Shear wave splitting and the dynamics of the hydrated mantle wedge in subduction regions constrained by the example of the Ryukyu subduction zone

    Takayoshi Nagaya, Andrew Walker, James M. Wookey, Simon Wallis, Kazuhiko Ishii, J.-Michael Kendall

    American Geophysical Union (AGU) Fall Meeting  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2016.12

  • Dislocation observation of olivine in antigorite peridotite

    Presentation date： 2016.09

  • Chemically driven formation of pull-apart structure of Cr-spinel

    The 123th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2016.09

  • Ductile deformation of metachert in the Northern Chichibu belt of central Shikoku

    The 123th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2016.09

  • Influence of the mis-indexing in SEM-EBSD measurements on antigorite CPO patterns

    Presentation date： 2016.09

  • Existence of the mis-indexing and its influence on CPO patterns in the measurements of antigorite crystal directions using SEM-EBSD

    The 123th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2016.09

  • Brucite as an important phase in the mantle wedge: evidence from the Sanbagawa belt, SW Japan

    Simon Wallis, Shunsuke Endo, Hirokazu Kawahara, Takayoshi Nagaya, Hiroshi Mori, Yoshihiro Asahara

    Japan Geoscience Union (JpGU) Meeting 2016  (Makuhari Messe, Chiba, Japan) 

    Presentation date： 2016.05

  • Chemically induced crack formation in Cr-spinel under hydrous conditions

    The 122th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2015.09

  • Petrological and field evidence for the importance of brucite in the shallow mantle wedge of the Sanbagawa subduction zone

    The 122th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2015.09

  • The affects of heating time scales and deformation on Raman spectra of carbonaceous material -developments in Raman geothermometry-

    The 122th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2015.09

  • Solid-state flow and fluid infiltration in serpentinized mantle wedge

     [Invited]

    The 122th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2015.09

  • Reconsideration of serpentinite in the shallow wedge mantle -Importance of brucite-

    Presentation date： 2015.05

  • Analysis of metamorphic history recorded in garnet: A combined EBSD and EPMA study

    Presentation date： 2015.05

  • S-wave ray path analysis constrains the distribution and dynamics of the hydrated mantle wedge

    Nagaya, T., Walker, A.M., Wookey, J.M., Kendall, M.J. & Wallis, S.R.

    The 2nd Japan-Taiwan Workshop on Crustal Dynamics (JTWCD)  (Nagoya University, Nagoya, Japan) 

    Presentation date： 2015.04

  • 浅部ウェッジマントルにおけるbrucite-antigorite serpentiniteの重要性

    河原 弘和, 遠藤 俊佑, ウォリス サイモン, 永冶 方敬, 森 宏, 山本 鋼志, 淺原 良浩

    変成岩などシンポジウム2015 

    Presentation date： 2015.03

  • 含水条件でのクロムスピネルの組成変化とクラック形成

    新井 翔, 水上 知行, 森下 知晃, 永冶 方敬, ウォリス サイモン

    変成岩などシンポジウム2015 

    Presentation date： 2015.03

  • EBSDとEPMAのコラボ

    榎並正樹, 永冶方敬

    変成岩などシンポジウム2015 

    Presentation date： 2015.03

  • 測定方法の違いがantigorite CPOに与える影響

    永冶 方敬, ウォリス サイモン, 曽田 祐介, 上原 誠一郎

    変成岩などシンポジウム2015 

    Presentation date： 2015.03

  • Possible petrological controls on the location and time scale of slow slip in SW Japan

    Simon Wallis, Tomoyuki Mizukami, Hironori Yokoyama, Yoshihiro Hiramatsu, Shoji Arai, Hirokazu Kawahara, Takayoshi Nagaya

    American Geophysical Union (AGU) Fall Meeting  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2014.12

  • Seismology in Ryukyu arc, Japan reveals the distribution and orientation of serpentine minerals suggesting convection and low viscosity of forearc mantle

    Takayoshi Nagaya, Andrew M. Walker, James M. Wookey, Michael J. Kendall & Simon R. Wallis

    American Geophysical Union (AGU) Fall Meeting  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2014.12

  • 地震波経路を利用したS波偏向異方性モデリングによるウェッジマントル内のアンチゴライトの分布範囲と含有率の推定法の開発

    永冶 方敬, ウォーカー アンドリュー, ウッキー ジェームズ, ケンダル マイケル, ウォリス サイモン

    日本地震学会 秋季大会  (新潟) 

    Presentation date： 2014.11

  • Constraints on time-scales for graphitization of carbonaceous material

    The 121th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2014.09

  • Interactions between the shallow wedge mantle and subducted slab ~ the Shiraga ultramafic body, Kochi prefecture ~

    The 121th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2014.09

  • Two types of antigorite serpentinite controlling heterogeneous slow-slip behaviours of slab-mantle interface

    The 121th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2014.09

  • Large-scale convection of the hydrated forearc mantle suggested by the seismic anisotropy modeling ~A case of Ryukyu arc~

    The 121th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2014.09

  • Slab-wedge mantle boundary preserved in the Sanbagawa belt, SW Japan

    Wallis Simon, Hiroshi Mori, Takayoshi Nagaya, Hirokazu Kawahara

    Japan Geoscience Union (JpGU) Meeting 2014  (Pacifico YOKOHAMA, Kanagawa, Japan) 

    Presentation date： 2014.04

  • Olivine CPO in non-deformed peridotite due to topotactic replacement of antigorite

    Takayoshi Nagaya, Simon R. Wallis, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami, Yusuke Seto, Akira Miyake, Megumi Matsumoto

    Japan Geoscience Union (JpGU) Meeting 2014  (Pacifico YOKOHAMA, Kanagawa, Japan) 

    Presentation date： 2014.04

  • Olivine CPO in non-deformed peridotite due to topotactic replacement of antigorite

    Takayoshi Nagaya, Simon R. Wallis, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami, Yusuke Seto, Akira Miyake, Megumi Matsumoto

    European Geosciences Union (EGU) General Assembly 2014  (Austria Center Vienna (ACV), Vienna, Austria) 

    Presentation date： 2014.04

  • 炭質物の石墨化における時間スケールの制約

    森宏・森なつみ, ウォリス サイモン・アナン, カトリーナ, ウェスタウェイ ロブ, カリッキ ルーカ, 纐纈佑衣, 永冶方敬

    変成岩などシンポジウム2014 

    Presentation date： 2014.03

  • 四国中央部に分布する白髪山超塩基性岩体の岩石学特徴

    河原 弘和, 永冶 方敬, 森 宏, ウォリス サイモン

    変成岩などシンポジウム2014 

    Presentation date： 2014.03

  • Topotaxy and the development of Olivine CPO

    永冶 方敬, ウォリス サイモン, 小林 広明, 道林 克禎, 水上 知行, 瀬戸雄介, 三宅 亮, 松本恵

    変成岩などシンポジウム2014 

    Presentation date： 2014.03

  • The distribution of antigorite and the mantle flow in the wedge mantle investigated by the shear wave splitting modeling

    The 120th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2013.09

  • Modeling shear wave anisotropy in forearc regions: implications for distribution of antigorite and olivine CPO fabrics

    Japan Geoscience Union (JpGU) Meeting 2013 

    Presentation date： 2013.05

  • MSATを用いた沈み込み帯前弧域の地震波偏向異方性モデリング

    永冶 方敬, ウォーカー アンドリュー, ウッキー ジェームズ, ケンダル マイケル, ウォリス サイモン

    変成岩などシンポジウム2013 

    Presentation date： 2013.03

  • Oriented growth due to topotactic replacement of antigorite by olivine as a mechanism for the formation of B-type olivine CPO in convergent margins

    Takayoshi Nagaya, Simon Wallis, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami

    American Geophysical Union (AGU) Fall Meeting  (San Francisco, United States of America, Moscone Center) 

    Presentation date： 2012.12

  • CPO formation mechanism of non-deformed olivine ~ a topotaxy in a reaction of antigorite -> olivine ~

    The 119th Annual Meeting of the Geological Society of Japan 

    Presentation date： 2012.09

  • Topotaxial growth of olivine and the formation of b-type CPO

    Simon Wallis, Takayoshi Nagaya, Hiroaki Kobayashi, Katsuyoshi Michibayashi, Tomoyuki Mizukami

    34th International Geological Congress (IGC)  (Brisbane Convention and Exhibition Centre, Queensland, Australia) 

    Presentation date： 2012.08

  • Dehydration breakdown of antigorite and the formation of b-type olivine CPO

    Japan Geoscience Union (JpGU) Meeting 2012 

    Presentation date： 2012.05

  • Dehydration breakdown of antigorite and the formation of b-type olivine CPO

    永冶 方敬, ウォリス サイモン

    変成岩などシンポジウム2012 

    Presentation date： 2012.03

▼display all

Research Projects

  • Investigation of deformation microstructure of shallow wedge mantle based on dehydration and deformation experiments of serpentinite

    Japan Society for the Promotion of Science (JSPS)  Multi-year Fund

    Project Year :

    2024.04
    -
    2028.03
     

    Takayoshi NAGAYA

  • Coupling of serpentinite deformation and metasomatism at subduction plate boundaries

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

    Project Year :

    2024.04
    -
    2027.03
     

  • Development of a program for acquiring techniques and skills for exhibiting and digitally archiving geological specimens

    Research Project on Improvement of Graduate School Education

    Project Year :

    2025.04
    -
    2026.03
     

    Osamu Takahashi, Naohisa NISHIDA, Takayoshi NAGAYA

  • Development of practical programs by creating a database and building a set of teaching materials of rock and mineral specimens and rock gardens of Tokyo Gakugei University and its affiliated schools

    Special Development Research Projects

    Project Year :

    2025.04
    -
    2026.03
     

    Naohisa NISHIDA, Yusaku GAMOU, Makiko MIYAGUCHI, Yoshihiro SEKITA, Takayoshi NAGAYA

  • Development of practical programs by creating a database and building a set of teaching materials of rock and mineral specimens and rock gardens of Tokyo Gakugei University and its affiliated schools

    Special Development Research Projects

    Project Year :

    2024.04
    -
    2025.03
     

    Takayoshi NAGAYA, Toshiya MITSUI, Makiko MIYAGUCHI, Naohisa NISHIDA, Yoshihiro SEKITA

  • Development of a program for acquiring techniques and skills for exhibiting and digitally archiving geological specimens

    Research Project on Improvement of Graduate School Education

    Project Year :

    2024.04
    -
    2025.03
     

    Takayoshi NAGAYA, Naohisa NISHIDA, Osamu TAKAHASHI

  • New developments in EBSD analysis applied to characterization of fault rock microstructure

    Japan Society for the Promotion of Science (JSPS)  Multi-year Fund

    Project Year :

    2020.10
    -
    2024.03
     

  • Estimation of Antigorite Serpentinite Structure of Wedge Mantle in Subduction Zones

    Japan Society for the Promotion of Science (JSPS)  Multi-year Fund

    Project Year :

    2020.04
    -
    2024.03
     

    Takayoshi NAGAYA

  • Strength mapping of continental crust in metamorphic core complexes of the western United States

    Japan Society for the Promotion of Science (JSPS)  Multi-year Fund

    Project Year :

    2017.04
    -
    2021.03
     

    Nagaya Takayoshi

    　View Summary

    Natural deformed rocks derived from the continental crust and exposed in the Ruby Mountains-East Humboldt Range of the western US were investigated. Obtained rock samples show the different deformation textures in rocks predicted to have been deformed under different deformation conditions in the continental crust. A set of these rock samples can provide us information of the rheological properties of under various deformation conditions in the crust. In laboratory experiments it was successful to obtain crystallographic orientation information of minerals and the Ti contents of quartz grains in samples. This achievement enables us to constrain the quantitative deformation conditions and is expected to contribute to construct a detailed strength profile through the crust.

  • Microstructural analysis of the Median Tectonic Line to elucidate the strength ofthe continental crusts

    Japan Society for the Promotion of Science (JSPS)  Single-year Grants

    Project Year :

    2016.04
    -
    2019.03
     

    Takayoshi NAGAYA

  • Elucidation of the ssubduction mechanism of antigorite

    Japan Society for the Promotion of Science (JSPS)  Single-year Grants

    Project Year :

    2013.04
    -
    2016.03
     

    Takayoshi NAGAYA

  • Graduate Student Exchange Program for Advanced Collaborative Research of Nagoya University

    Japan Student Services Organization (JASSO)  International Student Exchange Support Program

    Project Year :

    2014.03
    -
    2014.06
     

    Takayoshi NAGAYA

  • Earth Science Research Exchange between Nagoya University and the University of Bristol

    Japan Student Services Organization (JASSO)  International Student Exchange Support Program

    Project Year :

    2012.10
    -
    2013.01
     

    Takayoshi NAGAYA

  • Program for fostering young human resources for basic environmental studies (Short-term dispatch)

    Japan Society for the Promotion of Science (JSPS)  Institutional Program for Young Researcher Overseas Visit

    Project Year :

    2012.12
    -
    　
     

    Takayoshi NAGAYA

▼display all

Other

  • Self-organized seminar

    　View Summary

    【2025】
    Ganko (Structural Petrology & Geology + Rock Mineralogy) Seminar
    【2023 -】
    Earth Science Open Seminar /
    Occasional Guest Participant, Earth and Planetary Science Colloquium I (Petro-tectonics seminar), Graduate School of Science, The University of Tokyo.

  • Antigorite CPO formation mechanism in the shallow wedge mantle: Case studies from the Besshi and Shiraga bodies of the Sanbagawa metamorphic belt in central Shikoku, Japan

    　View Summary

    Nagaya Takayoshi;Wallis Simon R;Okamoto Atsushi;Uehara Seiichiro;Michibayashi Katsuyoshi;Nishii Aya

    Annual Meeting of the Geological Society of Japan
    https://doi.org/10.14863/geosocabst.2017.0_336

  • Talc CPO from talc-rich schists in the Sanbagawa and Franciscan metamorphic belts: implications as a weak layer formed due to Si-metasomatism at slab-mantle interfaces

    　View Summary

    Takayoshi Nagaya, Atsushi Okamoto, Simon Wallis, Ryosuke Oyanagi, Yusuke Seto, Akira Miyake, Masaoki Uno, Jun Muto, 17th International Workshop on WATER DYNAMICS 2020.3 (Conference canceled due to COVID-19)

  • Talc Crystal Preferred Orientation Patterns (CPO) and Seismic Anisotropy of Actinolite-Talc Schist from the Kamabuseyama Body in the Sanbagawa Belt of the Kanto Mountains, Japan

    　View Summary

    Takayoshi Nagaya, Simon R. Wallis, Asia Oceania Geosciences Society (AOGS) 2020 17th Annual meeting 2020.6 (Conference canceled due to COVID-19)

  • Importance of Kikuchi band number in EBSD determinations of antigorite crystal directions

    　View Summary

    Takayoshi Nagaya, Simon R. Wallis, The 19th International Conference on Textures of Materials (ICOTOM 19) 2020.9 (Withdrawn due to postponement of the conference due to the COVID-19 pandemic)

 

Syllabus

▼display all

Teaching Experience

  • Research on Structural Petrology

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Special seminar on Geology

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Master's Thesis (Department of Earth Sciences,Resources and Environmental Engineering)

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Seminar on Structural Petrology D

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Advanced Structural Petrology

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Seminar on Structural Petrology C

    Graduate School of Creative Science and Engineering, Waseda University  

    2025
    -
    Now
     

  • Seminar in Structural Geology

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Field Works on Geological Mapping

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Laboratory Work in General Earth Science II

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Structural Geology

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Exercise on Geological Mapping

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Introductory Seminar in Structural Geology

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Dynamism and Evolution of the Planet Earth

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Advanced Structural Geology

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Seminar in Earth Science

    School of Education, Waseda University  

    2025
    -
    Now
     

  • Field Research

    Graduate School of Education, Tokyo Gakugei University  

    2025
    　
    　
     

  • Special Exercises in Geoscience B

    Faculty of Education, Tokyo Gakugei University  

    2025
    　
    　
     

  • Special Exercises in Geoscience A

    Faculty of Education, Tokyo Gakugei University  

    2025
    　
    　
     

  • Earth Science B

    Faculty of Education, Tokyo Gakugei University  

    2024
    　
    　
     

  • Frontier Arts and Sciences M

    Faculty of Education, Tokyo Gakugei University  

    2024
    　
    　
     

  • Specialized Training for Teaching Profession BII

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Specialized Training for Teaching Profession AI

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Practical Exercises in Science II

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Advanced Research and Development Methods in Science

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Special Topics and Discussion in Science Frontier

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Advanced Research and Development Methods in Science

    Graduate School of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Graduation Research

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Earth Science Field Training

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Special Exercises in Earth and Environmental Sciences

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Introduction to Earth Sciences II

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Introductory Seminar for Science Course (Class B)

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Earth Science Experiments

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Geoscience Experiments

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Introduction to Earth Sciences I

    Faculty of Education, Tokyo Gakugei University  

    2023
    -
    2024
     

  • Studies of Existing Problems II

    Graduate School of Education, Tokyo Gakugei University  

    2023
    　
    　
     

  • Studies of Existing Problems B

    Graduate School of Education, Tokyo Gakugei University  

    2023
    　
    　
     

  • 地殻物質論

    Faculty of Education, Tokyo Gakugei University  

    2023
    　
    　
     

  • Earth and Planetary Science Colloquium II (Structural geology and tectonics seminar)

    Graduate School of Science, The University of Tokyo  

    2021
    -
    2022
     

  • Earth and Planetary Science Colloquium I (Structural geology and tectonics seminar)

    Graduate School of Science, The University of Tokyo  

    2021
    -
    2022
     

  • Experiments in Earth and Planetary Chemistry

    Faculty of Science, The University of Tokyo  

    2021
    -
    2022
     

  • Experiments in Earth and Planetary Physics

    Faculty of Science, The University of Tokyo  

    2021
    -
    2022
     

  • Exercise:Earth and Planetary Environmental Science

    Faculty of Science, The University of Tokyo  

    2021
    -
    2022
     

  • Practical:Analyses of Rock Textures I

    Faculty of Science, The University of Tokyo  

    2020
    -
    2022
     

  • Earth and Planetary Science Colloquium II (Solid Earth Forum)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Earth and Planetary Science Colloquium I (Solid Earth Forum)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Earth and Planetary Science Colloquium II (Petro-tectonics seminar)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Earth and Planetary Science Colloquium I (Petro-tectonics seminar)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Seminar of Current Scientific Literature II (Topics in structural petrology)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Seminar of Current Scientific Literature I (Topics in structural petrology)

    Graduate School of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Exercise:Physical Chemistry in Earth and Planetary Science

    Faculty of Science, The University of Tokyo  

    2019
    -
    2022
     

  • Basic Earth and Planetary Material Science

    Faculty of Science, The University of Tokyo  

    2021
    　
    　
     

  • Earth and Planetary Science Colloquium II (WSEP (Whole Solid Earth and Planet) seminar)

    Graduate School of Science, The University of Tokyo  

    2020
    -
    2021
     

  • Earth and Planetary Science Colloquium I (WSEP (Whole Solid Earth and Planet) seminar)

    Graduate School of Science, The University of Tokyo  

    2020
    -
    2021
     

  • Physics (Mechanics)

    Faculty of Engineering, Aichi Institute of Technology  

    2014
    -
    2015
     

▼display all

 

Academic Activities

  • 日本地質学会 若手巡検・研究集会 in 秩父ー長瀞 「三波川帯 ー片岩と変形構造が織りなす地形ー」（講師）

    Academic society, research group, etc.

    日本地質学会  

    2025.10
    　
    　

  • JpGU Meeting 2025 (Session [S-MP28])

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)  

    2025.05
    -
    　

  • JpGU Meeting 2024 (Field Trip)

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)  

    2024.06
    -
    　

    　View Summary

    In charge ofthe course of [FT-06] The Geology of Nagatoro, Chichibu: the birthplace of Geology in Japan (Simon Wallis, Takayoshi Nagaya)

  • JpGU Meeting 2024 (Session [S-MP24])

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)   Makuhari Messe

    2024.05
    -
    　

    　View Summary

    Session Convener and Chairperson at Session [S-MP24] Deformed rocks, Metamorphic rocks and Tectonics https://www.jpgu.org/meeting_e2024/sessionlist_en/detail/S-MP24.html

  • The 2nd International Association of Geo Chemistry (IAGC) International Conference (the 17th International Symposium on Water-Rock Interaction (WRI-17) / the 14th International Symposium Applied Isotope Geochemistry (AIG-14)) : Session [C-7]

    Academic society, research group, etc.

    The 17th International Symposium on Water-Rock Interaction (WRI-17)   Sendai International Center

    2023.08
    -
    　

    　View Summary

    Session Convener and Chairperson at Session [C-7] Mass and Energy Systems in Convergent Margins https://confit.atlas.jp/guide/event/wri17/session/1R207-08/class https://confit.atlas.jp/guide/event/wri17/session/1R209-10/class https://confit.atlas.jp/guide/event/wri17/session/1P70-71/class

  • The 2nd International Association of Geo Chemistry (IAGC) International Conference (the 17th International Symposium on Water-Rock Interaction (WRI-17) / the 14th International Symposium Applied Isotope Geochemistry (AIG-14)) (Field Trip)

    Academic society, research group, etc.

    17th International Symposium on Water-Rock Interaction (WRI-17)  

    2023.08
    -
    　

    　View Summary

    In charge ofthe course of P2 Nagatoro-Nikko in Post-conference tours (Takayoshi Nagaya, Atsushi Okamoto, Ryosuke Oyanagi)

  • JpGU Meeting 2023 (Session [S-MP26])

    Academic society, research group, etc.

    Japan geoscience union(JpGU)   Makuhari Messe

    2023.05
    -
    　

    　View Summary

    Session Convener and Chairperson at Session [S-MP26] Deformed rocks, Metamorphic rocks and Tectonics https://www.jpgu.org/meeting_e2023/sessionlist_en/detail/S-MP26.html

  • JpGU Meeting 2022 (Session [S-CG44])

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)   Online

    2022.06
    -
    　

    　View Summary

    Online Poster (andFlash Talk) Chairperson at [S-CG44] Science of slow-to-fast earthquakes https://confit.atlas.jp/guide/event/jpgu2022/session/SCG44_3PO1/detail

  • JpGU-AGU Joint Meeting 2020: Virtual (Session [S-MP40])

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)-American Geophysical Union (AGU)   Online

    2020.07
    -
    　

    　View Summary

    Session Convener, Chairperson and Discussion Forum Session (DFS) Panelist at Session [S-MP40] Thermal structure of subduction zones: modeling and the rock record https://confit.atlas.jp/guide/event/jpgu2020/session/SMP40_27PM1/advanced https://confit.atlas.jp/guide/event/jpgu2020/session/SMP40_27PO1/advanced

  • JpGU-AGU Joint Meeting 2017 (Session [S-GL33])

    Academic society, research group, etc.

    Japan Geoscience Union (JpGU)-American Geophysical Union (AGU)   Makuhari Messe

    2017.05
    -
    　

    　View Summary

    Session Convener and Chairperson at Session [S-GL33] Geodynamics of convergent margins: theoretical, laboratory and natural examples https://confit.atlas.jp/guide/event/jpguagu2017/session/SGL33_23AM1/class https://confit.atlas.jp/guide/event/jpguagu2017/session/SGL33_23PO1/class https://confit.atlas.jp/guide/event/jpguagu2017/session/SGL33_23PM1/class

▼display all

Sub-affiliation

  • Faculty of Science and Engineering   Graduate School of Creative Science and Engineering

Internal Special Research Projects

  • EBSDマップ解析の手法改良〜アンチゴライトの例〜

    2025  

    　View Summary

    本研究課題に関連して、2025年度には以下の査読付き国際学術誌に研究成果が論文として掲載された。&nbsp;１）Nagaya, T. and Wallis, S.R. (2025) The electron backscatter diffraction (EBSD) analysis procedure for crystal preferred orientations to reduce loss of EBSD map data: An example of antigorite. Journal of Mineralogical and Petrological Sciences, 120:017. https://doi.org/10.2465/jmps.241210&nbsp;２）Nagaya, T. and Wallis, S.R. (2026) Grain boundary sliding as a formation mechanism for the crystal preferred orientation of antigorite: the formation and development of B-type antigorite CPO patterns. Progress in Earth and Planetary Science, 13:4. https://doi.org/10.1186/s40645-025-00790-8&nbsp;３）Nagaya, T., Wallis, S.R. and Uehara, S. (2026) EBSD map analysis for antigorite deformation micro-textures related to dislocations: Implications for the effect of antigorite crystal structure on plastic deformation. Journal of Mineralogical and Petrological Sciences, 121:007. https://doi.org/10.2465/jmps.250814&nbsp;これらはいずれも、電子線後方散乱回折（Electron Backscatter Diffraction, EBSD）マッピングにより取得された岩石中の鉱物微細組織の解析に基づく研究成果であり、特にアンチゴライトと呼ばれる鉱物を主な対象としている。これらの研究成果は、アンチゴライトおよびアンチゴライトを含む岩石の変形過程に関する理解を深めることに貢献したと考えられる。またEBSDデータの解析手法の改良も提案しており、岩石の微細組織解析手法としてのEBSDの有用性および汎用性の向上にも寄与するものと考えられる。