人工地震時に認められた自然電位と磁場の変化

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: 2016/05/01

タイトル(英語): Induced Change of Electric Self-potential and Magnetic Field at the Artificial Explosion

著者名: 酒井　英男（富山大学大学院理工学研究部），小林　剛（富山大学大学院理工学研究部），泉　吉紀（富山大学大学院理工学研究部），中山　武（元 京都大学防災研究所上宝観測所），服部　克巳（千葉大学大学院理学研究科）

著者名(英語): Hideo Sakai (Department of Earth Sciences, University of Toyama), Tsuyoshi Kobayashi (Department of Earth Sciences, University of Toyama), Yoshinori Izumi (Department of Earth Sciences, University of Toyama), Takeshi Nakayama (Disaster Prevention Research Institute, Kyoto University), Katsumi Hattori (Department of Earth Sciences, Chiba University)

キーワード: 人工地震，自然電位，磁場，見かけ比抵抗　　explosion seismic experiment，electric self-potential，magnetic field，apparent resistivity

要約(英語): Study of the electric self-potential (SP) and the magnetic field was conducted at the explosion seismic experiment in Ooyama, Toyama Prefecture. The explosion was induced by 450 kg gun powder placed at a depth of 32.2-75 m. The SP was measured by four electrodes arranged in a line crossing the explosion point, where the distance of each electrode from the explosion ranged from 10 to 100 m. Induced SP changes consisted of two portions, namely, fluctuations with shorter periods (∼10 ms) and fluctuations with longer periods (∼50 ms). Regarding the latter, the amplitude was in proportion to the span length of electrode couples and the fluctuations arrived faster at the electrode couples nearer to the explosion. Further, the increment of ground level in SP was observed in each electrode couple after the explosion, which was concordant with the distribution of apparent resistivity underground studied by the survey. The magnetic field measured by the fluxgate magnetometer at the site 35 m north from the explosion also showed change of a few nT after the explosion. This may have been caused by change of magnetic properties underground.

本誌: 電気学会論文誌A（基礎・材料・共通部門誌） Vol.136 No.5 （2016） 特集：電磁界を用いた自然災害軽減のための観測・予測・解析技術

本誌掲載ページ: 291-296 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/136/5/136_291/_article/-char/ja/