Title :
Analysis of Seismic Electromagnetic Phenomena Using the FDTD Method
Author :
Wang, Yi ; Cao, Qunsheng
Author_Institution :
Coll. of Electron. & Inf. Eng., Nanjing Univ. of Aeronaut. & Astronaut. (NUAA), Nanjing, China
Abstract :
Anomalous electromagnetic (EM) phenomena of the ultra-low frequency (ULF) and the extremely low frequency (ELF) prior to or during earthquakes are analyzed using the geodesic finite-difference time-domain (FDTD) algorithm and accurate geological EM data. Firstly, the underground EM eruption caused by the earthquake physical process is simulated, and its effects on the surface EM field are analyzed.Based on a series of simulations, a new explanation to the former observed ULF and ELF anomalies prior to and during earthquakes is proposed. Thereafter, to explain the enhancement of the Schumann resonances (SRs) observed in recent years, localized D-region ionospheric anomalies and background lightning noises are added simultaneously into the earthquake EM simulations, and the results are discussed. Finally, the general rules of seismic EM phenomena in the frequency range 0-40 Hz are summarized, and potential earthquake prediction methods are suggested.
Keywords :
earthquakes; electromagnetic waves; finite difference time-domain analysis; ionospheric disturbances; lightning; seismic waves; Schumann resonances; background lightning noises; earthquake physical process; frequency 0 Hz to 40 Hz; geodesic finite difference time-domain method; localized D-region ionospheric anomalies; seismic electromagnetic phenomena; surface EM field; Earth; Earthquakes; Finite difference methods; Geophysical measurement techniques; Ground penetrating radar; Surface waves; Time domain analysis; Earthquake precursors; Schumann resonances (SRs); extremely low frequency (ELF); finite-difference time-domain (FDTD); ionosphere anomaly;
Journal_Title :
Antennas and Propagation, IEEE Transactions on
DOI :
10.1109/TAP.2011.2164204
