Seismic investigation of subducted ridge : Towards understanding mechanism of continental growth

2010 Fiscal Year Final Research Report

• Project/Area Number: 20253003
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Solid earth and planetary physics
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: IWAMORI Hikaru Tokyo Institute of Technology, 大学院・理工学研究科, 教授 (80221795)
• Co-Investigator(Kenkyū-buntansha): SHINOHARA Asanao 東京大学, 地震研究所, 教授 (90242172) ; ANMA Ryo 筑波大学, 生命環境科学研究科, 講師 (70311595)
• Project Period (FY): 2008 – 2010
• Keywords: 大陸成長 / 海嶺沈み込み / OBS / 地震波 / 構造探査 / 花崗岩 / 数値計算

Research Abstract

Thermal effects of subducted ridges and their roles in continental growth have been investigated, based on seismology, sedimentology, petrology-structural geology, and numerical simulation for the triple junction and the surrounding area in Chile and SW Japan. Natural earthquakes, subsidence and sedimentary environment in the forearc region, igneous activity and deformation history, and thermal-melting structure beneath the region have been constrained, indicating that a large amount of granitic melt can be produced associated with ridge subduction.

Research Products

• [Journal Article] Are the Taitao granites formed due to subduction of the Chile ridge? (2009)
  • Author(s): Anma, R., Armstrong, R., Orihashi, Y., Ike, S., Shin, K-C., Kon, Y., Komiya, T., Ota, T., Kagashima, S., Shibuya, T., Yamamoto, S., Velosoh, E.E., Fannin, M., Herve, F.
  • Journal Title: Lithos 113 Pages: 246-258
  • Peer Reviewed
• [Journal Article] Ophiolite emplacement and the effects of the subduction of the Chile Ridge System : Heterogeneous paleostress regimes recorded in the Taitao Ophiolite (Southern Chile). (2009)
  • Author(s): Veloso, E.E., Anma, R., Yamaji, A.
  • Journal Title: Andean Geology 36 Pages: 3-16
  • Peer Reviewed
• [Journal Article] 海嶺の沈み込みと三波川-領家変成岩および花崗岩の成因-広域ダイナミクス (2008)
  • Author(s): 岩森光
  • Journal Title: 物質循環との関連性-地学雑誌 117 Pages: 292-298
  • Peer Reviewed
• [Journal Article] Geochemical evidence for enhanced fluid flux due to overlapping subducting plates. (2008)
  • Author(s): Nakamura, H., Iwamori H., Kimura, J.
  • Journal Title: Nature Geoscience(doi:10.1038/ngeo200) 1
  • Peer Reviewed
• [Journal Article] Thermal and flow structure of subduction zones and water transportation into the deep mantle. (2008)
  • Author(s): 岩森光.
  • Journal Title: Geochim.Cosmochim.Acta 72 Pages: A416
  • Peer Reviewed
• [Presentation] 長期観測型海底地震計を用いたチリ三重会合点付近における地震活動 (2011)
  • Author(s): 篠原雅尚、山田知朗、杉岡裕子、伊藤亜妃、Matthew Miller、一瀬建日、Klaus Bataille、岩森光
  • Organizer: 日本地球惑星科学連合2011年度連合大会
  • Place of Presentation: 幕張(日本)
  • Year and Date: 2011-05-27
• [Presentation] Chronology, Petrology and Numerical Simulation for Cretaceous to Paleogene Granitic Rocks, SW Japan. (2011)
  • Author(s): Iida, K., Iwamori H., others
  • Organizer: Japan Geoscience Union Meeting
  • Place of Presentation: Makuhari, Japan.
  • Year and Date: 2011-05-26
• [Presentation] Recognition criteria of ophiolites formed due to ridge collision/subduction. (2010)
  • Author(s): Anma, R.
  • Organizer: Geological Society of America Tectonic Crossroads.
  • Place of Presentation: Ankara, Turkey.
  • Year and Date: 20101000
• [Presentation] Subduction of the Chile Ridge and Generation of Granite Magmas. (2010)
  • Author(s): Anma, R., Shin, K-C., Orihashi, Y., Kon, Y., Nakano, T., Armstrong, R.
  • Organizer: EGU General Assembly
  • Place of Presentation: Wien, Austria.
  • Year and Date: 20100500
• [Presentation] Magmatism and crustal deformation during subduction and tearing of a ridge-transform system. (2010)
  • Author(s): Anma, R., Orihashi, Y., Veloso, E.A., Shin, K-C.
  • Organizer: EGU General Assembly
  • Place of Presentation: Wien, Austria.
  • Year and Date: 20100500
• [Presentation] 長期観測型海底地震計を用いたチリ三重会合点付近における地震観測 (2010)
  • Author(s): 篠原雅尚、山田知朗、杉岡裕子、伊藤亜妃、Matthew Miller、一瀬建日、Klaus Bataille、岩森光
  • Organizer: 2010年度日本地球化学会年会
  • Place of Presentation: 熊谷(日本)
  • Year and Date: 2010-09-08
• [Presentation] Ridge subduction and evolution of continental crust .Chile ridge subduction zone. (2010)
  • Author(s): Anma, R., Shin, K-C., Orihashi, Y., Nakano, T., Abe, N.
  • Organizer: Japan Geoscience Union Meeting
  • Place of Presentation: Makuhari, Japan (invited).
  • Year and Date: 2010-05-27
• [Presentation] Thermal and flow structure of subduction zones and water transportation into the deep mantle. (2008)
  • Author(s): 岩森光.
  • Organizer: Goldschmidt Conference.
  • Place of Presentation: Vancouver, Canada.
  • Year and Date: 2008-07-17