Toba "Level 8" Eruption; its impact on Earth's climate, life and human

• Project/Area Number: 16H04067
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geology
• Research Institution: The University of Tokyo
• Principal Investigator: KURODA Junichiro 東京大学, 大気海洋研究所, 准教授 (10435836)
• Co-Investigator(Kenkyū-buntansha): 吉村 寿紘 国立研究開発法人海洋研究開発機構, 生物地球化学研究分野, 研究員 (90710070)
• Research Collaborator: Ota Yuki
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥18,330,000 (Direct Cost: ¥14,100,000、Indirect Cost: ¥4,230,000); Fiscal Year 2018: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000); Fiscal Year 2017: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2016: ¥10,660,000 (Direct Cost: ¥8,200,000、Indirect Cost: ¥2,460,000)
• Keywords: 火山灰 / トバ火山 / 古気候 / 古水温 / アルケノン / 掘削コア / 気候変動 / 更新性 / モンスーン / 層序 / 大規模噴火 / 火山ガラス / 有孔虫 / 酸素同位体

Outline of Final Research Achievements

We investigated a volcanic ash layer intercalating in a sediment core recovered from the Bay of Bengal, and identified its source and paleoclimatic conditions before and after the volcanic ash layers. Based on major, trance element abundances, and radiogenic isotopic compositions of Sr, Nd and Pb, we identified the ash layer as the Younger Toba Tephra (YTT) that erupted in 74-70 ka. Stratigraphy based on oxygen isotopic composition of planktonic foraminifera strongly supports the idea that the ash layer deposited around 74-70 ka. The sediment that includes YTT is characterized by very high sedimentation rate, that enables to reconstruct climate and ocean changes in high time resolution. We investigated temporal changes in paleo-seasurface temperature (SST) by analyzing alkenone compositions in millimeter scale.

Academic Significance and Societal Importance of the Research Achievements

インドネシア・スマトラ島のトバ火山は約7万年前に爆発的な噴火を起こした．その噴火は過去100万年間でも最大級といわれる．その時に噴出した火山灰は南アジア，インド洋，南シナ海と広く分布している．地球深部探査船「ちきゅう」でベンガル湾においてNGHP-02航海が実施され，トバ火山灰らしき火山灰層が回収された．本研究では，その火山灰層の詳細な検討と分析により，新期噴火のものであることを明らかにした．また，その火山灰層が含まれる堆積物は非常に堆積速度が高いため，高時間解像度での気候・海洋変動を記録している．火山灰層の直上，直下の堆積物の詳細な古水温記録を復元したところ，大変興味深い知見が得られた．

Research Products

• [Int'l Joint Research] UNIMORE/University of Parma/University of Palermo(イタリア)
• [Int'l Joint Research] University of Hawaii/Smithonian Nationa Museum(米国)
• [Int'l Joint Research] University Collage London(英国)
• [Int'l Joint Research] Geoscience Australia(オーストラリア)
• [Int'l Joint Research] University of Granada(スペイン)
• [Int'l Joint Research]
• [Journal Article] Efficient recycling of nutrients in modern and past hypersaline environments (2019)
  • Author(s): Isaji Y.、Kawahata H.、Ogawa N. O.、Kuroda J.、Yoshimura T.、Jimenez-Espejo F. J.、Makabe A.、Shibuya T.、Lugli S.、Santulli A.、Manzi V.、Roveri M.、Ohkouchi N.
  • Journal Title: Scientific Reports Volume: 9 Issue: 1 Pages: 3718-3718
  • DOI: 10.1038/s41598-019-40174-9
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Indian Monsoonal Variations During the Past 80?Kyr Recorded in NGHP-02 Hole 19B, Western Bay of Bengal: Implications From Chemical and Mineral Properties (2019)
  • Author(s): Ota Yuki、Kawahata Hodaka、Kuroda Junichiro、Yamaguchi Asuka、et al.
  • Journal Title: Geochemistry, Geophysics, Geosystems Volume: 20 Issue: 1 Pages: 148-165
  • DOI: 10.1029/2018gc007772
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Diazotrophy Drives Primary Production in the Organic-Rich Shales Deposited Under a Stratified Environment During the Messinian Salinity Crisis (Vena del Gesso, Italy) (2019)
  • Author(s): Isaji Yuta、Kawahata Hodaka、Takano Yoshinori、Ogawa Nanako O.、Kuroda Junichiro、Yoshimura Toshihiro、Lugli Stefano、Manzi Vinicio、Roveri Marco、Ohkouchi Naohiko
  • Journal Title: Frontiers in Earth Science Volume: 7 Pages: 1-13
  • DOI: 10.3389/feart.2019.00085
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Post-Eocene intensification of deep-water circulation in the central South Pacific: Micropalaeontological clues from dredged sites along the eastern Manihiki Plateau margin (2018)
  • Author(s): Ando Atsushi、Kuroda Junichiro、Werner Reinhard、Hoernle Kaj、Huber Brian T.
  • Journal Title: Terra Nova Volume: 31 Issue: 1 Pages: 28-38
  • DOI: 10.1111/ter.12366
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Lithium, magnesium and sulfur purification from seawater using an ion chromatograph with a fraction collector system for stable isotope measurements (2018)
  • Author(s): Yoshimura Toshihiro、Araoka Daisuke、Tamenori Yusuke、Kuroda Junichiro、Kawahata Hodaka、Ohkouchi Naohiko
  • Journal Title: Journal of Chromatography A Volume: 1531 Pages: 157-162
  • DOI: 10.1016/j.chroma.2017.11.052
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Suspected meteorite fragments in marine sediments from East Antarctica (2018)
  • Author(s): Naresh C. Pant, Francisco J. Jimenez-Espejo, Cary P. Cook, Paromita Biswas, Robert Mckay, Claudio Marchesi, Motoo Ito, Dewashish Upadhyay, Junichiro Kuroda, Kenji Shimizu, Ryoko Senda, Tina Van De Flierdt, Yoshinori Takano, Katsuhiko Suzuki, Carlota Escutia and Prakash K. Shrivastava
  • Journal Title: ANTARCTIC SCIENCE Volume: 30 Issue: 5 Pages: 307-321
  • DOI: 10.1017/s0954102018000299
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Alpine bogs of southern Spain show human-induced environmental change superimposed on long-term natural variations (2017)
  • Author(s): Antonio Garcia-Alix, Francisco J. Jimenez-Espejo, Jaime L. Toney, Gonzalo Jimenez-Moreno, Maria J. Ramos-Roman, R. Scott Anderson, Patricia Ruano, Ignasi Queralt, Antonio Delgado Huertas and Junichiro Kuroda
  • Journal Title: Scientific Reports Volume: 7 Issue: 1 Pages: 7439-7439
  • DOI: 10.1038/s41598-017-07854-w
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Characterization of sulfate mineral deposits in central Thailand (2017)
  • Author(s): Junichiro Kuroda, Hidetoshi Hara, Katsumi Ueno, Thasinee Charoentitirat, Teruyuki Maruoka, Takashi Miyazaki, Akira Miyahigashi and Stefano Lugli,
  • Journal Title: Island Arc Volume: 26 Issue: 2
  • DOI: 10.1111/iar.12175
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Biological and physical modification of carbonate system parameters along the salinity gradient in shallow hypersaline solar salterns in Trapani, Italy (2017)
  • Author(s): Isaji Y., H. Kawahata, J. Kuroda, T. Yoshimura, N. O. Ogawa, A. Suzuki, T. Shibuya, F. J. Jimenez-Espejo, S. Lugli, A. Santulli, V. Manzi, M. Roveri, and N. Ohkouchi
  • Journal Title: Geochimica et Cosmochimica Acta Volume: 印刷中 Pages: 354-367
  • DOI: 10.1016/j.gca.2017.04.013
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] 海洋堆積物の重元素の同位体組成が語る表層環境変動 (2017)
  • Author(s): 黒田潤一郎
  • Journal Title: 地球化学 Volume: 51 Pages: 15-28
  • NAID: 130005531001
  • Peer Reviewed
• [Journal Article] 古い海洋プレートのみ込み直前での屈曲断層形成に伴う加水作用解明に向けた海洋掘削計画概要 (2017)
  • Author(s): 森下知晃, 藤江剛, 山野誠, 中西正男, 尾鼻浩一郎, 中村恭之, 斎藤実篤, 小平秀一, 木村純一, 黒田潤一郎, 小野重明
  • Journal Title: 地学雑誌 Volume: 126 Pages: 247-262
  • Peer Reviewed
• [Journal Article] Response of the Pacific intertropical convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition (2016)
  • Author(s): Kiseong Hyeong, Junichiro Kuroda, Inah Seo and Paul A. Wilson,
  • Journal Title: Scientific Reports Volume: 6 Issue: 1 Pages: 30647-30647
  • DOI: 10.1038/srep30647
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] Stratigraphy of the Cretaceous-Paleogene transition interval at the Lord Howe Rise, southern Pacific. (2018)
  • Author(s): Junichiro Kuroda, Saneatsu Saito, Yoichi Usui, Kyoko Hagino, Paul R Bown, Kan-Hsi Hsiung, Saburo Sakai, Ron I. Hackney and Naohiko Ohkouchi
  • Organizer: American Geophysical Union, 2019 Fall Meeting
  • Int'l Joint Research
• [Presentation] Reconstruction of the marine Os-isotope record across the Aptian/Albian boundary to shed light on the relationships between Oceanic Anoxic Event 1b and massive volcanic activities. (2018)
  • Author(s): Hirornao Matsumoto, Junichiro Kuroda, Rodolfo Coccioni, Naohiko Ohkouchi, Nanako O. Ogawa, Katsuhiko Suzuki, Fabrizio Frontalini and Andrea Mazzoli
  • Organizer: American Geophysical Union, 2019 Fall Meeting
  • Int'l Joint Research
• [Presentation] 固体地球活動に起因する中期中新世の温暖化：オスミウム同位体と炭素循環モデルを用いた検証. (2018)
  • Author(s): 後藤孝介, Maria Luisa L. Tejada, Gregory Ravizza, 伊藤孝, 黒田潤一郎, 鈴木勝彦
  • Organizer: 日本地球惑星科学連合2018年大会
  • Invited
• [Presentation] Porphyrins reveal modes of nitrogen cycle controlled by chemocline depth under density-stratified condition during the Messinian Salinity Crisis. (2018)
  • Author(s): 伊左治雄太, 川幡穂高, 高野淑識, 小川奈々子, 黒田潤一郎, 吉村寿紘, Stefano Lugli, Vinicio Manzi, Marco Roveri, 大河内直彦
  • Organizer: 日本地球惑星科学連合2018年大会
  • Invited
• [Presentation] 下部白亜系上部アプチンから下部アルビンにかけての海洋オスミウム同位体比記録の復元. (2018)
  • Author(s): 松本廣直, 黒田潤一郎, Rodolfo Coccioni, 大河内直彦, Fabrizio Frontalini
  • Organizer: 日本地質学会第125年学術大会
• [Presentation] 温室効果ガスの放射強制力に応答した西太平洋暖水塊の表層水温変動. (2018)
  • Author(s): 佐川拓也, 向田圭佑, 山崎俊嗣, 久保田好美, 黒田潤一郎
  • Organizer: 日本地球惑星科学連合2018年大会
• [Presentation] 地中海メッシニアン期塩分危機に形成された蒸発岩のマグネシウム同位体組成. (2018)
  • Author(s): 吉村寿紘, 荒岡大輔, 黒田潤一郎, 伊左治雄太, Francisco J. Jiménez-Espejo, Stefano Lugli, Vinicio Manzi, Marco Roveri, 大河内直彦
  • Organizer: 日本地球惑星科学連合2018年大会
• [Presentation] Decoding Earth's surface environment by osmium isotope records of marine sediments (2016)
  • Author(s): Junichiro Kuroda, Katsuhiko Suzuki and Naohiko Ohkouchi
  • Organizer: International Conference on Paleoceanography
  • Int'l Joint Research / Invited
• [Presentation] Miocene to Pleistocene osmium isotopic records of the Mediterranean and Atlantic sediments (2016)
  • Author(s): Junichiro Kuroda, Francisco J. Jimenez-Espejo, Tatsuo Nozaki, Rocco Gennari, Stefano Lugli, Vinicio Manzi, Marco Roveri, Rachel Flecker, Francisco J. Sierro, Toshihiro Yoshimura, Katsuhiko Suzuki and Naohiko Ohkouchi
  • Organizer: The 26th Goldschmidt Conference
  • Int'l Joint Research
• [Presentation] 海洋堆積物の重元素の同位体組成が語る表層環境変動 (2016)
  • Author(s): 黒田潤一郎, 鈴木勝彦, 大河内直彦
  • Organizer: 日本地球化学会2016年度年会
  • Invited
• [Presentation] The Lord Howe Rise drilling project (2016)
  • Author(s): Ron Hackney, 山田泰広, Kliti Grice, 黒田潤一郎, Jessica H. Whiteside, Marco Coolen, 稲垣史生, Richard Arculus, Dietmar R. Mueller, 斎藤実篤, 西弘嗣
  • Organizer: 日本地球惑星科学連合2016年大会