Ionospheric penetration characteristics of ELF waves radiated from a current source in the lithosphere related to seismic activity

DOI Web Site Web Site 被引用文献1件
  • M. Ozaki
    Graduate School of Natural Science and Technology Kanazawa University Kanazawa Japan
  • S. Yagitani
    Graduate School of Natural Science and Technology Kanazawa University Kanazawa Japan
  • I. Nagano
    Kanazawa University Kanazawa Japan
  • K. Miyamura
    PFU Ltd. Kahoku‐shi Japan

書誌事項

公開日
2009-02
権利情報
  • http://onlinelibrary.wiley.com/termsAndConditions#vor
DOI
  • 10.1029/2008rs003927
公開者
American Geophysical Union (AGU)

この論文をさがす

説明

<jats:p>Electromagnetic wave radiation from an underground current source related to seismic activity is discussed. In order to estimate the ionospheric effects on the electromagnetic waves associated with the seismic activity, ELF waves in the frequency range from 10 Hz to 1 kHz in the ionosphere radiated from a possible seismic current source modeled as an electric dipole located in the lithosphere, are precisely computed by using a full‐wave analysis. In this calculation, the ionosphere is assumed to be an inhomogeneous and anisotropic medium, and the Earth's crust is assumed to be a homogeneous and isotropic conductive medium. Especially, the effects of the geomagnetic field on the ionospheric wave propagation are precisely considered. The results of the calculations in the frequency range from 10 Hz to 1 kHz show frequency dependence in spatial distributions of the wave intensities due to the geomagnetic field‐aligned whistler propagation in the ionosphere and the Earth‐ionosphere waveguide propagation. Wave intensities which could be observed on the ground and in the ionosphere are determined by assuming the magnitude of the current moment of a seismic dipole source. In a possible situation, the current moment is estimated to be about 80 A·m/Hz<jats:sup>1/2</jats:sup> which generates a detectable wave magnetic field on the ground just above a seismic source. However, if we try to detect it in the ionosphere, the source current moment must be thousands of times more intense.</jats:p>

収録刊行物

  • Radio Science

    Radio Science 44 (1), 2009-02

    American Geophysical Union (AGU)

被引用文献 (1)*注記

もっと見る

問題の指摘

ページトップへ