2011年東北地方太平洋沖地震（Mw9.0）に関連する地磁気日変化異常の時空間的特徴

カテゴリ: 論文誌(論文単位)

グループ名: 【A】基礎・材料・共通部門

発行日: 2017/02/01

タイトル(英語): Time-Spatial Analysis of Geomagnetic Diurnal Variations Associated with the 2011 off the Pacific Coast of Tohoku Earthquake (Mw9.0)

著者名: 韓　鵬（千葉大学大学院理学研究科），服部　克巳（千葉大学大学院理学研究科），山口　拓人（千葉大学大学院理学研究科），廣岡　伸治（千葉大学大学院理学研究科），吉野　千恵（千葉大学大学院理学研究科）

著者名(英語): Peng Han (Graduate School of Science, Chiba University), Katsumi Hattori (Graduate School of Science, Chiba University), Takuto Yamaguchi (Graduate School of Science, Chiba University), Shinji Hirooka (Graduate School of Science, Chiba University), Chie Yoshino (Graduate School of Science, Chiba University)

キーワード: 地震磁場現象，地磁気日変化異常，時空間解析，ウェーブレット変換，2011年東北地方太平洋沖地震　　seismo-magnetic phenomena，anomalous geomagnetic diurnal variation，time-spatial analysis，wavelet transform，the 2011 off the Pacific coast of Tohoku earthquake

要約(英語): Recent studies have reported unusual behaviors of geomagnetic diurnal variation (GDV) in the vertical component prior to the 2011 off the Pacific coast of Tohoku earthquake (Mw 9.0). To make a better understanding of this phenomenon, time-spatial analysis of GDV has been applied in this study. Geomagnetic data of long term observations at 17 stations in Japan have been analyzed using the same method in Han et al. 2015. Ratios of diurnal variation range between the target station and the reference station KAK have been computed. After removing seasonal variations revealed by wavelet transform analysis, the 15-day mean values of the ratios in the vertical component shows a clear anomaly exceeding the statistical threshold about 2 months before the mega event in both ESA and MIZ stations in the Tohoku Region. Similar results could not be found in other regions of Japan. Spatial distributions of the ratios show a good agreement between the location of the anomalies and the epicenter of Mw 9.0 earthquake. These time-spatial results are consistent with independent results obtained from other observations such as radon density, seismicity, and GPS displacements, which suggest the geomagnetic data might be useful in earthquake monitoring and disaster mitigation.

本誌: 電気学会論文誌A（基礎・材料・共通部門誌） Vol.137 No.2 （2017） 特集：2015 Korea-Japan Joint Symposium on Electrical Discharge and High Voltage Engineering並びに放電研究の最新動向

本誌掲載ページ: 119-127 p

原稿種別: 論文／日本語

電子版へのリンク: https://www.jstage.jst.go.jp/article/ieejfms/137/2/137_119/_article/-char/ja/