Research on non-volcanic tremor occurrence process using dense seismic array observation

• Project/Area Number: 19740269
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: KURASHIMO Eiji The University of Tokyo, 地震研究所, 助教 (00302620)
• Project Period (FY): 2007 – 2008
• Project Status: Completed (Fiscal Year 2008)
• Budget Amount: ¥3,510,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥210,000); Fiscal Year 2008: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2007: ¥2,600,000 (Direct Cost: ¥2,600,000)
• Keywords: 非火山性深部低周波微動 / 地震波速度構造 / フィリピン海プレート / 稠密地震計アレイ観測 / 反射法断面図 / 地震現象

Research Abstract

西南日本の沈み込み帯では非火山性深部低周波微動が観測されているが,その発生過程に関する明快な結論は得られていない.紀伊半島南部で取得した稠密アレイ観測データと既存データの統合解析の結果より,反射法断面図で確認できるフィリピン海プレートに対応する反射層の層厚は一定ではなく,定常滑り領域下で厚くなっていること,低周波地震は,反射層が厚くなる領域内で発生し,微動発生域の近傍では,Low Vp, high Vp/Vsの特徴を示すことが明らかになった.これらのことから,微動の発生過程において流体の関与が示唆される.

Research Products

• [Presentation] Detailed structure of the locked-sliding transition on the subducting plate boundary beneath the southern part of Kii peninsula (2008)
  • Author(s): Eiji Kurashimo, Aitaro Kato, Naoshi Hirata, Takaya Iwasaki, Takashi Iidaka, Kiyoshi Ito, Fumihito Yamazaki, Kaoru Miyashita, Kazushige Obara
  • Organizer: southwestern Japan, Deep Seismic Profiling of the Continents and, their Margins
  • Place of Presentation: Finland, Saariselka
  • Year and Date: 2008-06-08
• [Presentation] Detailed structure of the locked-sliding transition on the subducting plate boundary beneath the southern part of Kii peninsula, southwestern Japan (2008)
  • Author(s): Kurashimo, E.,A. Kato, N. Hirata, T. Iwasaki, T. Iidaka, K. Ito, F. Yamazaki, K. Miyashita and K. Obara
  • Organizer: Deep Seismic Profiling of the Continents and their Margins
  • Place of Presentation: Saariselka, Finland
  • Year and Date: 2008-06-08
• [Presentation] Three-dimensional Seismic Structure of the Locked-Sliding Transition on the Subducting Plate Boundary beneath the Southern Part of Kii Peninsula (2007)
  • Author(s): Eiji Kurashimo, Aitaro Kato, Naoshi Hirata, Takaya Iwasaki, Takashi Iidaka, Kiyoshi Ito, Fumihito Yamazaki, Kaoru Miyashita, Kazushige Obara
  • Organizer: Southwestern Japan, 2007 AGU Fall meeting
  • Place of Presentation: USA, San Francisco
  • Year and Date: 2007-12-13
• [Presentation] Three-dimensional Seismic Structure of the Locked-Sliding Transition on the Subducting Plate Boundary beneath the Southern Part of Kii Peninsula, Southwestern Japan (2007)
  • Author(s): Eiji Kurashimo, Aitaro Kato, Naoshi Hirata, Takaya Iwasaki, Takashi Iidaka, Kiyoshi Ito, Fumihito Yamazaki, Kaoru Miyashita, Kazushige Obara
  • Organizer: 2007 AGU Fall meeting
  • Place of Presentation: アメリカ・サンフランシスコ
  • Year and Date: 2007-12-13