High-resolution geomagnetic observation system using HTS-SQUID

• Katori Yuta

  Graduate School of System Design, Tokyo Metropolitan University

• Isogami Shinji

  Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science

• Hato Tsunehiro

  Superconducting Sensing Technology Research Association

• Tsukamoto Akira

  Superconducting Sensing Technology Research Association

• Tanabe Keiichi

  Superconducting Sensing Technology Research Association

• Ohnishi Nobuhito

  TIERRA TECNICA Ltd.

• Furukawa Chikara

  TIERRA TECNICA Ltd.

• Okubo Kan

  Graduate School of System Design, Tokyo Metropolitan University

Abstract

Our research group reported successful observation of “co-faulting” Earth’s magnetic field changes because of piezomagnetic effects caused by earthquake tremors during the 2008 Iwate-Miyagi Nairiku earthquake of M7.2 using a geomagnetic observation system with flux-gate magnetometers. This is an important finding: electromagnetic fields propagate from a source to an observation site at the light speed in the crustal materials. Further earthquake detection efforts can lead us to a new system for super-early warning of earthquake detection with the geomagnetic signal. However, the observed result with the earthquake was suggested that the geomagnetic field change accompanying fault movement, whose sources are the piezomagnetic effects, is very small and short term. Therefore, to develop an extremely important high-resolution magnetometer system, we first conducted long-term precise geomagnetic observations using a high-temperature superconductor based superconducting quantum-interference device (HTS-SQUID) magnetometer system. The HTS-SQUID magnetometer system had never been used for high-resolution geomagnetic observations outdoors. Since March 2012, we have observed geomagnetic field using the HTS-SQUID magnetometer at Iwaki observation site (IWK) in Fukushima, Japan. Comparison between the introduced HTS-SQUID magnetometer and conventional flux-gate clarified that the HTS-SQUID magnetometer in our system has higher resolution of magnetic field observation.

Journal

• IEICE Communications Express

  IEICE Communications Express 7 (3), 71-76, 2018

  The Institute of Electronics, Information and Communication Engineers

Keywords

• HTS-SQUID
• magnetometer
• geomagnetic observation
• high-resolution

Details

• CRID: 1390001205416565120
• NII Article ID: 130006407908
• DOI: 10.1587/comex.2017xbl0168
• ISSN: 21870136
• Web Site: https://www.jstage.jst.go.jp/article/comex/7/3/7_2017XBL0168/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed