Fate of the Oceanic Crust Reveled by Stochastic Seismic Wave Tomography

• Project/Area Number: 25400439
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: Takeuchi Nozomu 東京大学, 地震研究所, 准教授 (90313048)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2014: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2013: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 地震 / 地球内部構造 / 散乱 / トモグラフィー / 散乱波 / 地震波

Outline of Final Research Achievements

The purpose of this project was to extend the deterministic tomography and establish the stochastic tomography using seismic waveforms. By such stochastic tomography, we can expect to resolve chemical heterogeneities that have not been well resolved by previous deterministic approaches. We developed an appropriate Monte-Carlo method to invert seismogram envelopes. Using our method and up-to-date broadband OBS (ocean bottom seismology) data, we succeeded to show the possibility that we can directly show the strong heterogeneities in the lithosphere and the strong internal attenuation in the asthenosphere. Our results should open the new way of future seismological analysis.

Research Products

• [Journal Article] Upper Mantle Tomography in the Northwestern Pacific Region Using Triplicated P Waves (2014)
  • Author(s): Takeuchi, N., H. Kawakatsu, S. Tanaka, M. Obayashi, Y. J. Chen., J. Ning, S. P. Grand, F. Niu, J. F Ni, R. Iritani, K. Idehara, T. Toneg
  • Journal Title: Journal of Geophysical Research Volume: 119 Issue: 10 Pages: 7667-7685
  • DOI: 10.1002/2014jb011161
  • Peer Reviewed
• [Journal Article] Intricate heterogeneous structures of the top 300 km of the Earth's inner core inferred from global array data : II. Frequency dependence of inner core attenuation and its implication (2014)
  • Author(s): Iritani, R., Takeuchi, N. & Kawakatsu, H.
  • Journal Title: Earth Planet. Sci. Lett. Volume: 405 Pages: 231-243
  • DOI: 10.1016/j.epsl.2014.08.038
  • Peer Reviewed
• [Journal Article] On the possibility of lunar core phase detection using new seismometers for soft-landers in future lunar missions (2013)
  • Author(s): Yamada, R., Garcia, R.F., Lognonne, P., Kobayashi, N., Takeuchi, N., Nebut, T., Shiraishi, H., Calvet, M. & Ganepain-Beyneix, J.
  • Journal Title: Planet. Space Sci. Volume: 81 Pages: 18-32
  • DOI: 10.1016/j.pss.2013.03.009
  • Peer Reviewed
• [Journal Article] Can a sheet-like low-velocity region form an elongated Large Igneous Province? (2013)
  • Author(s): Namiki, A., Sueyoshi, K. & Takeuchi, N.
  • Journal Title: Geochem. Geophys. Geosys. Volume: 14 Issue: 8 Pages: 3053-3066
  • DOI: 10.1002/ggge.20182
  • Peer Reviewed
• [Presentation] Velocity structure model dependence of upper, middle and lower crust volume (2016)
  • Author(s): Nozomu Takeuchi
  • Organizer: 2nd Workshop on KamLAND Geoscience; Toward Enhanced Reference Earth Models for Geoneutrino Analysis
  • Place of Presentation: 東京大学（東京都・文京区）
  • Year and Date: 2016-03-23
  • Int'l Joint Research
• [Presentation] Seismological Constraints on Velocity and Density in the Earth's Core (2016)
  • Author(s): Nozomu Takeuchi
  • Organizer: 1st Neutrino Oscillation Tomography Workshop
  • Place of Presentation: 東京大学（東京都・文京区）
  • Year and Date: 2016-01-07
  • Int'l Joint Research
• [Presentation] Seismic Tomography by Statistical Approach (2015)
  • Author(s): Nozomu Takeuchi
  • Organizer: Workshop ERI-IPGP: Geodynamics, earthquakes and volcanic eruptions
  • Place of Presentation: パリ（フランス）
  • Year and Date: 2015-09-24
  • Int'l Joint Research
• [Presentation] Local refined Earth model for KamLAND geo-neutrino analysis (2015)
  • Author(s): Nozomu Takeuchi
  • Organizer: Neutrino Geoscience 2015 Conference
  • Place of Presentation: パリ（フランス）
  • Year and Date: 2015-06-15
  • Int'l Joint Research
• [Presentation] 表面波解析に基づく３次元地殻変動観測と長周期励起源への応用 (2015)
  • Author(s): 竹内 希
  • Organizer: 日本地球惑星科学連合大会
  • Place of Presentation: 幕張メッセ（千葉県・千葉市）
  • Year and Date: 2015-05-25
• [Presentation] Upper Mantle Tomography in the Northwestern Pacific Region Using Triplicated P Waveforms (2014)
  • Author(s): N. Takeuchi, H. Kawakatsu, S. Tanaka, M. Obayashi, Y. Chen, J. Ning, S. Grand, F. Niu, J. Ni, R. Iritani, K. Idehara & T. Tonegawa
  • Organizer: AGU Fall Meeting
  • Place of Presentation: サンフランシスコ（米国）
  • Year and Date: 2014-12-15
  • Invited
• [Presentation] コーダエンベロープ波形インバージョンによる散乱特性推定 (2014)
  • Author(s): 竹内 希
  • Organizer: 日本地震学会
  • Place of Presentation: 朱鷺メッセ（新潟県新潟市）
  • Year and Date: 2014-11-26
• [Presentation] 最近のグローバルトモグラフィーモデル：我々はどこに向かっているのか？ (2014)
  • Author(s): 竹内 希
  • Organizer: 日本地球惑星科学連合大会
  • Place of Presentation: パシフィコ横浜（神奈川県横浜市）
  • Year and Date: 2014-04-29
  • Invited
• [Presentation] 地球ニュートリノデータの地球物理学的インバージョン：地球の化学構造を制約するための定式化 (2014)
  • Author(s): 竹内 希
  • Organizer: 日本地球惑星科学連合大会
  • Place of Presentation: パシフィコ横浜（神奈川県横浜市）
  • Year and Date: 2014-04-28
  • Invited
• [Presentation] Absence of the Stagnant Slab beneath Northeast China Constrained by a Seismic Station in Mongolia (2013)
  • Author(s): 竹内 希・NECESSArray Project Team
  • Organizer: 日本地球惑星科学連合大会
  • Place of Presentation: 幕張メッセ（千葉市）