雷管石の磁化-雷による熱影響と地磁気の記録の研究

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: 2014/10/01

タイトル(英語): Magnetization of Fulgurite as a Fossil of the Heating Effect of Lightning Strikes

著者名: 酒井　英男（富山大学理学部），巽　雅敬（（株）サンコーシヤ），安井　晋示（名古屋工業大学大学院つくり領域）

著者名(英語): Hideo Sakai (Faculty of Science, University of Toyama), Masahiro Tatsumi (Sankosha Corporation), Shinji Yasui (Tsukuri College, Nagoya Institute of Technology)

キーワード: 雷電流，熱残留磁化，雷管石，地磁気　　lightning current，thermal remanent magnetization，fulgurite，geomagnetic field

要約(英語): Sakai et al.(1)(3)(8) demonstrated that a strong magnetic field at a lightning strike induces isothermal remanent magnetization in the materials around the point of lightning strike. In some cases, the ground or underground materials, or both are possibly heated by the lightning strike. They may thereby, acquire another type of magnetization, called thermal remanent magnetization. Fulgurite that is produced underground at the lightning is a typical result of the heating effect caused by the lightning electric current.We investigated the remanent magnetization of fulgurite found at Iwamizawa, Hokkaido, Japan. The study verified that the fulgurite has thermal remanent magnetization which recorded the geomagnetic field. We estimate that the temperature of the fulgurite immediately after the lightning strike was over Curie temperature (580℃) of the included magnetite minerals. Experimental results indicate that when the fulgurite was formed, the lightning current already disappeared and did not affect the remanent magnetization. A magnetic study at the lightning-damaged area could investigate the heating effect of lightning current as well as its path and magnitude.

本誌: 電気学会論文誌A（基礎・材料・共通部門誌） Vol.134 No.10 （2014）

本誌掲載ページ: 545-552 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/134/10/134_545/_article/-char/ja/