Updated on 2025/05/15

写真a

 
CHO, Tenichi
 
Affiliation
Affiliated organization, Center for Data Science
Job title
Assistant Professor(without tenure)

Research Experience

  • 2023.04
    -
    Now

    Waseda University   Center for Data Science   Assistant Professor

  • 2023.04
    -
    2024.03

    統計数理研究所 統計エキスパート人材育成プロジェクト 第2期研修

  • 2021.04
    -
    2023.03

    Waseda University   Faculty of Science and Engineering

  • 2017.04
    -
    2022.07

    Waseda University   School of Education   Teaching Assistant

Education Background

  • 2018.04
    -
    2023.03

    Waseda University   Graduate School of Creative Science and Engineering   Department of Earth Sciences, Resources and Environmental Engineering  

  • 2014.04
    -
    2018.03

    Waseda University   School of Education   Department of Science  

    Earth Science Major

Research Areas

  • Solid earth sciences / Atmospheric and hydrospheric sciences / Biogeosciences

Research Interests

  • Sedimentology

  • Paleoenvironment

  • Chemical weathering

  • Global warming

  • Cretaceous

  • Triassic

  • Compositional data analysis

▼display all

Awards

  • GeoSciAI2024 優秀賞

    2024.05   Japan Geoscience Union  

  • 日本堆積学会論文賞

    2024.04   日本堆積学会  

  • アーリーバードプログラム 共同研究計画発表 最優秀賞

    2022.03   早稲田大学理工学術院総合研究所  

  • The Best Poster Presentation Award

    2019.10   International Geoscience Programme 679  

 

Papers

  • Physicochemical characterization of the youngest active domain in major fault zones using the weathering index and X-ray computed tomography

    Akiyuki Iwamori, Yasuhiro Ogita, Koji Shimada, Ryo Tateishi, Hideo Takagi, Tohru Ohta, Tenichi Cho, Shunsuke Kudo, Keisuke Nojiri, Yasumune Shigemitsu, Masaya Ogawa

    Engineering Geology   344   107821 - 107821  2025.01

    DOI

    Scopus

    1
    Citation
    (Scopus)

  • 静岡県熱海市伊豆山港沖に流出した盛土の底質と有孔虫群集への影響調査

    北村 晃寿, 松野 由奈, 守屋 和佳, 張 天逸, 小林 大翔, 岡嵜 颯太, 山下 裕輝, 古屋 俊和, 島田 帆菜

    静岡大学地球科学研究報告書   ( 51 ) 17 - 33  2024.04

    DOI

  • Did changes in terrigenous components of deep-sea cherts across the end-Triassic extinction relate to Central Atlantic magmatic province volcanism?

    Masayuki Ikeda, Tenichi Cho, Maximilien Bôle

    Frontiers in Earth Science   11  2023.07

    　View Summary

    The end-Triassic mass extinction event (ETE) is considered to be linked with the emplacement of the Central Atlantic magmatic province (CAMP), yet their temporal relation and underlying nature of global environmental and biotic changes remain controversial. A drastic radiolarian faunal turnover was associated with deep-sea acidification and changes in the chemical composition of pelagic terrigenous components, which were interpreted as the results of increased CAMP-derived materials, such as Fe2O3/Al2O3, MgO/Al2O3, and SiO2/Al2O3, without statistical tests. Here, we re-examined these CAMP-like signatures in terms of changes in the chemical composition of the Triassic–Jurassic pelagic deep-sea chert succession in Japan. Our newly compiled dataset suggests that changes in Fe2O3/Al2O3 and MgO/Al2O3 across the ETE were not significant, and thus, they may not be appropriate proxies for CAMP-derived material, potentially due to the dissolution of iron by ocean acidification and the formation of chlorite during diagenesis, respectively. Decreased SiO2/Al2O3 was also considered to have been reflected in increased CAMP-related dust flux and/or decreased biosiliceous productivity, but a slight increase in the Al2O3/TiO2 ratio (a biosiliceous productivity proxy) and an increase in shale bed thickness (dust flux proxy) across the radiolarian ETE imply increased eolian dust flux rather than decreased productivity. Furthermore, statistically significant Na enrichment at the radiolarian ETE level might be related to CAMP volcanism and/or associated changes in the source areas of eolian dust.

    DOI

    Scopus

  • Shallow- and deep-ocean Fe cycling and redox evolution across the Pliensbachian–Toarcian boundary and Toarcian Oceanic Anoxic Event in Panthalassa

    Wenhan Chen, David B. Kemp, Tianchen He, Robert J. Newton, Yijun Xiong, Hugh C. Jenkyns, Kentaro Izumi, Tenichi Cho, Chunju Huang, Simon W. Poulton

    Earth and Planetary Science Letters   602  2023.01

    　View Summary

    The late Pliensbachian to early Toarcian was characterized by major climatic and environmental changes, encompassing the early Toarcian Oceanic Anoxic Event (T-OAE, or Jenkyns Event, ∼183 Ma) and the preceding Pliensbachian–Toarcian boundary event (Pl/To). Information on seawater redox conditions through this time interval has thus far come mainly from European sections deposited in hydrographically restricted basins, and hence our understanding of the redox evolution of the open ocean (and in particular Panthalassa – the largest ocean to have existed) is limited. Here, we present high-resolution Fe-speciation and redox-sensitive trace metal data from two Panthalassic Ocean sections across the Pl/To and the T-OAE intervals, one deposited in deep water (paleo-water depth >∼2.7 km) and the other on a shallow margin (paleo-water depth likely <∼50 m). Data from the deep-water open-ocean site indicate anoxic-ferruginous conditions from the late Pliensbachian to the onset of the T-OAE, with a rather fluctuating redox state alternating between oxic and anoxic/euxinic conditions across the Pl/To boundary. At least intermittent bottom-water euxinia characterized the T-OAE, followed by a subsequent transition toward more oxygenated conditions. By contrast, trace metal data from the shallow margin site indicate that oxygenated to possibly suboxic conditions prevailed. However, elevated highly reactive iron contents, dominated by Fe (oxyhydr)oxides, characterize this shallow-water site. These observations suggest that upwelling, driven in part by increased sea level and prevailing winds from the open ocean, brought anoxic-ferruginous waters onto the shelf, whereupon Fe2+ oxidation was initiated in oxic shallow waters.

    DOI

    Scopus

    15
    Citation
    (Scopus)

  • A robust chemical weathering index for sediments containing authigenic and biogenic materials

    Tenichi Cho, Tohru Ohta

    Palaeogeography, Palaeoclimatology, Palaeoecology   608  2022.12

    　View Summary

    Chemical weathering is an important process at Earth's surface. Given that the chemical composition of sediments reflects the weathering environment in which they were generated, this can provide insights into the intensity and style of weathering during the past. Weathering indices calculated from the whole-rock geochemical compositions of sedimentary rocks are widely used. However, these indices have limitations, such as contamination by non-silicate minerals. To develop a weathering index widely applicable to sedimentary rocks formed under various conditions, we used compositional data and multivariate statistics to analyse a dataset for igneous rocks and their weathering profiles. The chemical variations of the igneous rocks and weathering trends were independently extracted from the dataset, and a new weathering index (the robust weathering (RW) index) is proposed. The applicability of the RW index was assessed using saprolite profiles and zonal soils. We further applied the RW index to a carbonate-rich paleosol to test its use in studies of paleoclimate. The RW index is robust even for sediments containing a large amount of non-silicate materials, and thus enables comparison of the weathering intensity of a wide range of sedimentary rocks. Spatial–temporal reconstructions of paleo-weathering conditions will be improved by applying the RW index to terrestrial and marine sediments.

    DOI

    Scopus

    16
    Citation
    (Scopus)

  • Major sulfur cycle perturbations in the Panthalassic Ocean across the Pliensbachian-Toarcian boundary and the Toarcian Oceanic Anoxic Event

    Wenhan Chen, David B. Kemp, Robert J. Newton, Tianchen He, Chunju Huang, Tenichi Cho, Kentaro Izumi

    Global and Planetary Change   215  2022.08

    　View Summary

    The early Toarcian Oceanic Anoxic Event (T-OAE, ~183 Ma) was characterized by marine deoxygenation and the burial of organic-rich sediments at numerous localities worldwide. However, the extent of marine anoxia and its impact on the sulfur cycle during the T-OAE is currently poorly understood. Here, stable sulfur isotopes of reduced metal-bound sulfur (δ34Spyrite) and pyrite sulfur concentrations (SPY) have been analyzed across the Pliensbachian-Toarcian boundary (Pl-To) and the T-OAE from the Sakahogi and Sakuraguchi-dani sections (Japan), which were deposited in the deep and shallow Panthalassic Ocean, respectively. Our data reveal marked positive δ34Spyrite excursions of >10‰ across both the Pl-To and the T-OAE at Sakahogi, coincident with increases in SPY, and a positive excursion of >20‰ at the onset of the T-OAE at Sakuraguchi-dani. Whilst the development of deep-water anoxic/euxinic conditions could have resulted in an enhanced burial of pyrite, and also partly contributed to the positive excursion of δ34Spyrite, variations in δ34Spyrite at Sakahogi were most likely controlled by elevated export production and/or preservation. On the shallow shelf generally low and highly variable SPY and the positive shift in δ34Spyrite were likely attributable mainly to elevated sedimentation rates, with redox playing only a minor role in controlling pyrite abundance. Our discovery of a positive δ34Spyrite excursion across the Pl-To at Sakahogi indicates a hitherto unrecognized perturbation to the deep-water sulfur cycle, potentially associated with increased seafloor organic matter flux and pyrite burial at this time, consistent with a transient interval of anoxia.

    DOI

    Scopus

    6
    Citation
    (Scopus)

  • Increased Terrigenous Supply to the Pelagic Panthalassa Superocean Across the Carnian Pluvial Episode: A Possible Link With Extensive Aridification in the Pangean Interior

    Tenichi Cho, Masayuki Ikeda, Tohru Ohta

    Frontiers in Earth Science   10  2022.06

    　View Summary

    In the Late Triassic, a global environmental change called the Carnian Pluvial Episode (CPE) emerged, causing major biological turnover. The CPE has been recognized by siliciclastic input to sedimentary basins, multiple carbon isotope perturbations, and climate proxies for humidification. The CPE is considered to have been associated with increased atmospheric pCO2 from eruptions of large igneous provinces. However, the nature of this global environmental perturbation on the continents is still not well understood. Here we present a geochemical analysis of a pelagic deep-sea bedded chert sequence across the CPE in the Jurassic accretionary complex of Mino terrane, central Japan. Fluctuations in terrigenous material supply were reconstructed using Principal Component Analysis of major element compositions. The first principal component positively correlates with elements enriched in clay minerals such as Al2O3, whereas it negatively correlates with CaO, P2O5, and MnO, derived from apatite and manganese. A sudden increase in terrigenous supply was detected around the Julian/Tuvalian boundary, suggesting that CPE-related siliciclastic input also occurred in the abyssal plain environment. The terrigenous supply returned to the pre-CPE state in the Tuvalian. Since the terrigenous material supplied to the abyssal plain is thought to be derived from eolian dust blown from continental arid regions, the increasing terrigenous supply detected in the pelagic deep-sea chert succession may indicate extensive aridification. This result seems to conflict with the common view of the CPE as a humidification event. This contradiction possibly suggests that the extensive aridification occurred within the interior of the supercontinent Pangea, while hydrological circulation enhanced on the coastal region during the CPE.

    DOI

    Scopus

    6
    Citation
    (Scopus)

  • Deep-ocean anoxia across the Pliensbachian-Toarcian boundary and the Toarcian Oceanic Anoxic Event in the Panthalassic Ocean

    David B. Kemp, Wenhan Chen, Tenichi Cho, Thomas J. Algeo, Jun Shen, Masayuki Ikeda

    Global and Planetary Change   212  2022.05

    　View Summary

    The early Toarcian Oceanic Anoxic Event (T-OAE, or Jenkyns Event, ~183 million years ago) was a major hyperthermal and global carbon-cycle perturbation, likely associated with the release of a substantial volume of 12C-enriched carbon to the Earth's surface. Seawater deoxygenation and the associated deposition of organic-rich facies during this event have been noted in many locations around the world, but evidence for pervasive and extreme oceanic anoxia has thus far been described mainly from European sections deposited in hydrographically restricted basins. Here we present new geochemical data on redox changes during the T-OAE, as well as the preceding Pliensbachian-Toarcian boundary (Pl/To) event, from a deep Panthalassic Ocean site at Inuyama, Japan. Redox-sensitive trace element data reveal an extended interval of seawater deoxygenation that began prior to the Pl/To and continued to the end of the T-OAE. A marked expansion of anoxic and possibly euxinic conditions to the seafloor occurred during both the Pl/To and T-OAE, accompanied by increased organic carbon burial. During these intervals of severe deep-ocean deoxygenation, our data suggest a global drawdown of trace elements such as Mo, U and As. Our findings highlight that: (1) the Panthalassic Ocean was likely an important locus of deoxygenation and organic carbon burial during the early Toarcian, and (2) the spread of anoxia during the T-OAE was a globally distributed phenomenon.

    DOI

    Scopus

    28
    Citation
    (Scopus)

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Research Projects

  • 化学風化度から読み解く白亜紀東アジアの陸域環境

    深田地質研究所  深田研究助成

    Project Year :

    2024.04
    -
    2025.03
     

  • High-resolution study of Carnian Pluvial Episode to elucidate the relationship between igneous activity, climate change, and biological evolution

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

    Project Year :

    2021.04
    -
    2023.03
     

  • 地球生命共進化メカニズムの解明：中生代三畳紀における火成活動・陸域気候・海洋環境の同時復元

    早稲田大学理工学術院総合研究所  アーリーバードプログラム

    Project Year :

    2021.04
    -
    2022.03
     

  • 層状チャートの古環境復元媒体としての有用性の解明を目的とする野外調査

    深田地質研究所  深田野外調査助成

    Project Year :

    2020.04
    -
    2021.03
     

Misc

  • Evaluation of the hinterland paleoweathering during the mid- to late-Cretaceous in Northwestern Kyusyu, Japan

    Nakano A., Toda N., Cho T., Ohta T.

    the 37th International Geological Congress    2024.08

  • Development of a new silicate weathering index (RW) and its application to the Early Cretaceous strata distributed in East Asia

    Cho T, Ohta T, Li G

    the 37th International Geological Congress    2024.08

  • 堆積物の化学組成データを用いた定量的な古環境復元方法の検討

    張天逸

    第6回統計エキスパート人材育成プロジェクト中間報告会    2024.06

  • Possible changes in weathering process through the Aptian Oceanic Anoxic Event (OAE 1a) recorded in the Cretaceous deep-sea bedded chert

    Nakagawa Y, Cho T, Ikeda M

    Japan Geoscience Union Meeting 2024 (Chiba, Japan), Japan Geoscience Union.    2024.05

  • Development of a new silicate weathering index (RW) and its application to the climate reconstruction

    Cho T, Ohta T

    Japan Geoscience Union Meeting 2024 (Chiba, Japan), Japan Geoscience Union.    2024.05

  • 堆積学トーク・トーク「いまどきのフィールド調査」（演題："空撮写真を用いた堆積岩試料採取の再現性の向上"）

    張天逸

    日本堆積学会2024年熊本大会    2024.04

  • 天草・御船地域における中期-後期白亜紀の後背地風化度と古気候変動

    中野 有紗, 戸田 仁香, 張 天逸, 太田 亨

    日本堆積学会2024年熊本大会講演要旨集     48  2024.04

  • Did Lunar Granites form by Silicate Liquid Immiscibility similar to Melt Inclusions in Northwest Africa 773? Log-ratio Analysis of Chemical Compositions

    Fagan,J,T, Cho,T, Sawada,Y

    55th Lunar and Planetary Science Conference(Houston, Texas)    2024.03

  • 堆積物の化学組成を用いた多変量統計解析に基づく汎用性の高い古環境復元指標の提示

    張 天逸

    データ関連人材育成プログラム（D-DRIVE） 若手研究交流会    2024.03

  • 生物源物質及び続成由来物質の混入に強固な風化指標の構築と東アジア白亜系への適用

       2023.12

  • 過去の地球表層環境解明のための現世土壌の化学組成を用いた気候パラメータの復元

    張 天逸

    第１回早稲田大学データ科学研究交流会    2023.09

  • Introduction of a robust chemical weathering index for sediments containing authigenic and biogenic materials and its application to Cretaceous strata distributed in SE Asia

    Tenichi CHO, Tohru OHTA, Gang LI

       2023.08

  • A new chemical weathering index for sediments containing authigenic and biogenic materials: RW index

    CHO Tenichi, OHTA Tohru

    Annual Meeting of the Geological Society of Japan   2022   170  2022.09

    DOI

  • Shallow and deep ocean Fe cycling and redox evolution across the Pliensbachian-Toarcian

    Chen, W, He, T, Kemp, D, Xiong, Y, Izumi, K, Cho, T, Huang, C, Newton, R, Poulton, S

    Goldschmidt conference 2022 (virtual), European Association of Geochemistry.    2022.07

  • 美濃帯層状チャートを用いた遠洋域への風成塵供給量の復元：Carnian Pluvial Episodeにおける陸域環境変動への示唆

    張 天逸, 池田 昌之, 太田 亨

    日本堆積学会2022年オンライン大会講演要旨    2022.04

  • 地球生命共進化メカニズムの解明：中生代三畳紀における火成活動，陸域気候，海洋環境の同時復元

    張 天逸

    2021年度理工学術院総合研究所第11期アーリーバードプログラム研究成果報告    2022.03

  • Paleoclimate evaluation during the mid-Cretaceous in Zhejiang Province, southeast China

    Okano, K, Nakano, A, Cho, T, Ohta, T, Li, G

    35th IAS Meeting of Sedimentology (virtual) Book of Abstracts International Association of Sedimentologist     331 - 331  2021.06

  • Reconstruction of climate condition in the Carnian from bedded chert by using a new index of chemical weathering

    Cho, T

    JpGU-AGU Joint Meeting (virtual), Japan Geoscience Union.    2020.07

  • A robust chemical weathering index applicable to a wide range of sedimentary rocks

    Cho, T, Ohta, T

    Goldschmidt conference 2020 (virtual), European Association of Geochemistry.    2020.06

  • A report on the IAS field trip “Microbial carbonate reservoirs architecture:From depositional facies to seismic scale geometriesin the Triassic of the Dolomites (Italy)”

    Cho Tenichi

    Journal of the Sedimentological Society of Japan   78 ( 2 ) 111 - 115  2020.02

    DOI CiNii

  • Late Triassic continental weathering fluctuation recorded in pelagic sediments distributed in Inuyama section, central Japan

    Cho, T, Ohta, T

    34th IAS Meeting of Sedimentology (Rome, Italy) Book of Abstracts International Association of Sedimentologist.     251 - 251  2019.09

  • Hinterland paleo-weathering variation recorded in the Inuyama bedded chert and its relationship with the Carnian Pluvial Event

    Cho Tenichi, Ebisawa Shun, Ohta Tohru

    Annual Meeting of the Geological Society of Japan   2019   453  2019.09

    DOI CiNii

  • Evaluation of hinterland weathering and paleoclimate of the Cretaceous strata in the Sichuan basin, central China

    Cho, T, Mantani, H, Ohta, T, Li G

    Japan Geoscience Union Meeting 2019 (Chiba, Japan), Japan Geoscience Union.    2019.05

  • Evaluation of Cretaceous hinterland weathering and climate in the Sichuan Basin SW China

    Cho, T, Mantani, H, Ohta, T. Li, G

    Open Journal of Geology   9   696 - 699  2019

  • Estimates of aeolian dust supply variation in the Inuyama bedded chert sequence: Evidence of Pangean mega-monsoon

    Cho Tenichi, Ohta Tohru

    Annual Meeting of the Geological Society of Japan   2018   475  2018.09

    DOI CiNii

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Syllabus

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Sub-affiliation

  • Affiliated organization   Global Education Center

Internal Special Research Projects

  • 顕生代の陸源砕屑性堆積岩に普遍的に適用できる古気候パラメータの復元指標の開発

    2024  

    　View Summary

    堆積岩の化学組成は，過去の風化度の情報を保持していることから，古気候解析に有用である．本研究では，様々な気候帯に発達する現世土壌の化学組成と現地の気象データを比較して，多変量統計解析の手法を用いて化学組成から温度や降水量といった具体的な気候パラメータを復元する指標を構築するための基礎研究を行った．解析データ取得のため，現世土壌の化学組成の文献調査による収集を行った．実際に古気候解析に適用するデータの取得のため，蛍光X線分光法，誘導結合プラズマ質量分析法によって，白亜系の堆積岩試料の分析を行った．現段階での予察的な解析結果を「The 37th International Geological Congress」において発表した．

  • 顕生代の堆積岩に適用可能な定量的な古気候指標の開発

    2023  

    　View Summary

    堆積岩の化学組成は，過去の風化度の情報を保持していることから，古気候解析に有用である．本研究では，様々な気候帯に発達する現世土壌の化学組成と現地の気象データを比較して，多変量統計解析の手法を用いて化学組成から温度や降水量といった具体的な気候パラメータを復元する指標を構築するための基礎研究を行った．解析データ取得のため，現世土壌の化学組成の文献調査による収集を行った．実際に古気候解析に適用するデータの取得のため，蛍光X線分光法，誘導結合プラズマ質量分析法によって，三畳系の堆積岩試料の分析を行った．現段階での予察的な解析結果を「第1回早稲田大学データ科学研究交流会」において発表した．