Structure and dynamics of the Earth's inner core boundary-The origin of hemispherical structure-

• Project/Area Number: 21340132
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: TANAKA Satoru 独立行政法人海洋研究開発機構, 地球内部ダイナミクス領域, 主任研究員 (60281961)
• Co-Investigator(Kenkyū-buntansha): MATSUSHIMA Masaki 東京工業大学, 理工学研究科, 助教 (20242266) ; SHIMIZU Hisayoshi 東京大学, 地震研究所, 准教授 (70302619)
• Project Period (FY): 2009 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥18,200,000 (Direct Cost: ¥14,000,000、Indirect Cost: ¥4,200,000); Fiscal Year 2012: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000); Fiscal Year 2011: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2010: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000); Fiscal Year 2009: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000)
• Keywords: 内核境界 / 内核成長 / ダイナモシミュレーション

Research Abstract

Hemispherical difference of the inner core reaches at least 400km below the inner core boundary. Attenuation of seismic wave passing through the Eastern hemisphere can be explained by velocity perturbation within the uppermost 200km of the inner core. The reflected waves at the inner core boundary in the Eastern hemisphere show that 2Hz components are larger than those of 1Hz. The stability of morphology at the inner core surface depends on the growth rate of the inner core. Diffusivity affects kinetic and magnetic (in some case) energies of the outer core flow near the inner core boundary.

Research Products

• [Journal Article] One-dimensional modeling of multiple scattering in the upper inner core: Depth extent of a scattering region in the Eastern hemisphere (2013)
  • Author(s): Tanaka, S
  • Journal Title: J. Earth Sci Volume: (in press)
  • Peer Reviewed
• [Journal Article] One-dimensional modeling of multiple scattering in the upper inner core: Depth extent of a scattering region in the Eastern hemisphere (2013)
  • Author(s): Tanaka, S.
  • Journal Title: J. Earth Sci. Volume: 印刷中
  • Peer Reviewed
• [Journal Article] The effect of anisotropic diffusivity on rotating magnetoconvection in the Earth's core (2012)
  • Author(s): Matsushima, M
  • Journal Title: Geophys. Astrophys. Fluid Dyn Volume: 106 Issue: 6 Pages: 630-642
  • DOI: 10.1080/03091929.2011.641959
  • Peer Reviewed
• [Journal Article] Depth extent of hemispherical inner core from PKP(DF) and PKP(Cdiff) for equatorial paths (2012)
  • Author(s): Tanaka, S
  • Journal Title: Phys. Earth Planet. Inter Volume: 210-211 Pages: 50-62
  • Peer Reviewed
• [Journal Article] Depth extent of hemispherical inner core from PKP(DF) and PKP(Cdiff) for equatorial paths (2012)
  • Author(s): Tanaka, S.
  • Journal Title: Phys. Earth Planet. Inter. Volume: 210-211 Pages: 50-62
  • DOI: 10.1016/j.pepi.2012.08.001
  • Peer Reviewed
• [Presentation] A new probe of the inner core boundary (2012)
  • Author(s): Tanaka, S. and Tkalcic, H
  • Organizer: Frequency dependent amplitude ratio of PKiKP/PcP observed at the Hinet array(招待), AGU2012
  • Place of Presentation: サンフランシスコ, USA
  • Year and Date: 2012-12-03
• [Presentation] Hinetで観測されたPKiKP/PcP振幅比の周波数依存性 (2012)
  • Author(s): Tanaka, S. and Tkalcic, H
  • Organizer: 地震学会 2012年秋季大会
  • Place of Presentation: 函館
  • Year and Date: 2012-10-18
• [Presentation] Influence of thermal boundary condition and anisotropic diffusivity on dynamics in the Earth's core, SEDI2012 (2012)
  • Author(s): Matsushima, M
  • Organizer: SEDI2012
  • Place of Presentation: リーズ, イギリス
  • Year and Date: 2012-07-03
• [Presentation] Frequency dependent amplitude ratio of PKiKP/PcP observed at the Hinet array (2012)
  • Author(s): Tanaka, S. and Tkalcic, H
  • Organizer: Possible detection of a thin liquid layer above the inner core boundary, SEDI2012
  • Place of Presentation: リーズ, イギリス
  • Year and Date: 2012-07-02
• [Presentation] Effects of thermal boundary condition and anisotropic thermal diffusivity in the Earth's core (2012)
  • Author(s): Matsushima, M
  • Organizer: 日本地球惑星科学連合2012年大会
  • Place of Presentation: 千葉
  • Year and Date: 2012-05-25
• [Presentation] Latitudinal dependence of some effects of anisotropic thermal diffusivity in the Earth's core (2011)
  • Author(s): Matsushima, M
  • Organizer: IUGG2011
  • Place of Presentation: メルボルン, オーストラリア
  • Year and Date: 2011-07-02
• [Presentation] Depth variation of inner core hemisphericity from PKP(DF) and PKP(Cdiff) (2011)
  • Author(s): Tanaka, S
  • Organizer: P-wave velocity and attenuation structures for equatorial paths, IUGG2011
  • Place of Presentation: メルボルン, オーストラリア
  • Year and Date: 2011-07-02
• [Presentation] Depth variation of inner core hemisphericity from PKP (DF) and PKP (Cdiff) : P-wave velocity and attenuation structures for equatorial paths (2011)
  • Author(s): S.Tanaka
  • Organizer: IUGG2011
  • Place of Presentation: オーストラリア,メルボルン
  • Year and Date: 2011-07-02
• [Presentation] Latitudinal dependence of some effects of anisotropic thermal diffusivity in the Earth's core (2011)
  • Author(s): M.Matsushima
  • Organizer: IUGG2011
  • Place of Presentation: オーストラリア,メルボルン
  • Year and Date: 2011-07-02
• [Presentation] The effect of anisotropic diffusivity on rotating magnetoconvection in the Earth's core (2010)
  • Author(s): Matsushima, M
  • Organizer: SEDI 2010
  • Place of Presentation: カリフォルニア大学サンタバーバラ校, USA.
  • Year and Date: 2010-07-23
• [Presentation] The effect of anisotropic diffusivity on rotating magnetoconvection in the Earth's core (2010)
  • Author(s): M.Matsushima
  • Organizer: SEDI 2010
  • Place of Presentation: カリフォルニア大学サンタバーバラ校
  • Year and Date: 2010-07-23
• [Presentation] Spatial variations of differential travel times and amplitude ratios between PKP-Cdiff and PKP-DF (2010)
  • Author(s): Tanaka, S
  • Organizer: SEDI 2010
  • Place of Presentation: カリフォルニア大学サンタバーバラ校, USA
  • Year and Date: 2010-07-19
• [Presentation] Spatial variations of differential travel times and amplitude ratios between PKP-Cdiff and PKP-DF (2010)
  • Author(s): S.Tanaka
  • Organizer: SEDI 2010
  • Place of Presentation: カリフォルニア大学サンタバーバラ校
  • Year and Date: 2010-07-19
• [Presentation] Array analysis of PKP(BC) phase with station corrections for travel times and amplitudes (2009)
  • Author(s): Tanaka, S
  • Organizer: AGU Fall Meeting 2009
  • Place of Presentation: モスコーンセンター,サンフランシスコ,USA
  • Year and Date: 2009-12-16
• [Presentation] Array analysis of PKP(BC)phase with station corrections for travel times and amplitudes (2009)
  • Author(s): S.Tanaka
  • Organizer: AGU Fall Meeting 2009
  • Place of Presentation: モスコーンセンター, サンフランシスコ, USA
  • Year and Date: 2009-12-16
• [Presentation] Global and local MHD turbulence in the Earth's core (2009)
  • Author(s): Matsushima, M
  • Organizer: AGU Fall Meeting 2009
  • Place of Presentation: モスコーンセンター,サンフランシスコ,USA
  • Year and Date: 2009-12-15
• [Presentation] Global and local MHD turbulence in the Earth's core (2009)
  • Author(s): M.Matsushima
  • Organizer: AGU Fall Meeting 2009
  • Place of Presentation: モスコーンセンター, サンフランシスコ, USA
  • Year and Date: 2009-12-15
• [Presentation] Effects of anisotropic tensor diffusivity on the core dynamics (2009)
  • Author(s): Matsushima, M
  • Organizer: 第126回地球電磁気・地球惑星圏学会
  • Place of Presentation: 金沢大学,金沢
  • Year and Date: 2009-09-28
• [Presentation] Effects of anisotropic tensor diffusivity on the core dynamics (2009)
  • Author(s): M.Matsushima
  • Organizer: 第126回地球電磁気・地球惑星圏学会
  • Place of Presentation: 金沢大学, 金沢市
  • Year and Date: 2009-09-28
• [Presentation] Frequency dependent amplitude ratio of PKiKP/PcP observed at the Hinet array: Possible detection of a thin liquid layer above the inner core boundary
  • Author(s): Tanaka, S. and Tkalcic, H.
  • Organizer: SEDI2012
  • Place of Presentation: リーズ、イギリス
• [Presentation] Hinetで観測されたPKiKP/PcP振幅比の周波数依存性
  • Author(s): Tanaka, S. and Tkalcic, H.
  • Organizer: 日本地震学会 2012年 秋季大会
  • Place of Presentation: 函館
• [Presentation] A new probe of the inner core boundary: Frequency dependent amplitude ratio of PKiKP/PcP observed at the Hinet array
  • Author(s): Tanaka, S. and Tkalcic, H.
  • Organizer: AGU2012 Fall Meeting
  • Place of Presentation: サンフランシスコ、アメリカ
  • Invited
• [Presentation] Effects of thermal boundary condition and anisotropic thermal diffusivity in the Earth’s core
  • Author(s): Matsushima, M.
  • Organizer: 日本地球惑星科学連合2012年大会
  • Place of Presentation: 幕張
• [Presentation] Influence of thermal boundary condition and anisotropic diffusivity on dynamics in the Earth’s core
  • Author(s): Matsushima, M.
  • Organizer: SEDI2012
  • Place of Presentation: リーズ、イギリス
• [Book] 地球電磁気・地球惑星圏学会編, 太陽地球系科学(第12章 地球ダイナモ) (2010)
  • Author(s): 松島政貴
  • Publisher: 京都大学学術出版会
• [Book] 太陽地球系科学(第12章地球ダイナモ) (2010)
  • Author(s): 地球電磁気・地球惑星圏学会編松島政貴(分担)
  • Publisher: 京都大学学術出版会
• [Remarks] 田中 聡
  • URL: http://www.jamstec.go.jp/res/ress/stan/TanakaHome/Welcome.html