A statistical study on the correlation between lower ionospheric perturbations as seen by subionospheric VLF/LF propagation and earthquakes

Author

Hayakawa, M. ; Kasahara, Y. ; Nakamura, T. ; Muto, F. ; Horie, T. ; Maekawa, S. ; Hobara, Y. ; Rozhnoi, A.A. ; Solovieva, M. ; Molchanov, O.A.

Author_Institution

Adv. Wireless Commun. Res. Center, Univ. of Electro-Commun., Chofu, Japan

fYear

2011

fDate

13-20 Aug. 2011

Firstpage

1

Lastpage

4

Abstract

The subionospheric VLF/LF propagation is extensively used to investigate the lower ionospheric perturbation in possible association with earthquakes. An extensive period of data over seven years from January 2001 to December 2007 and a combination of different propagation paths in and around Japan are used to examine the statistical correlation between the VLF/LF propagation anomaly (average nighttime amplitude, dispersion and nighttime fluctuation) and earthquakes with magnitude greater than 6.0. It is then found that the propagation anomaly exceeding the 2σ (standard deviation) criterion indicating the presence of ionospheric perturbation is significantly correlated with earthquakes with shallow depth (<;40km). Finally some comments on the mechanism of seismo-ionospheric perturbations are discussed.

Keywords

earthquakes; ionospheric disturbances; ionospheric techniques; radiowave propagation; seismic waves; seismology; statistical analysis; AD 2001 01 to 2007 12; Japan; average nighttime amplitude; earthquakes; lower ionospheric perturbation; nighttime fluctuation; propagation anomaly; seismo-ionospheric perturbation; statistical study; subionospheric LF propagation; subionospheric VLF propagation; wave dispersion; Correlation; Dispersion; Earth; Earthquakes; Electromagnetics; Noise measurement; Transmitters;

fLanguage

English

Publisher

ieee

Conference_Titel

General Assembly and Scientific Symposium, 2011 XXXth URSI

Conference_Location

Istanbul

Print_ISBN

978-1-4244-5117-3

Type

conf

DOI

10.1109/URSIGASS.2011.6050946

Filename

6050946