Detection of earth‐origin electric pulses

Using a newly developed system for measuring the electromagnetic (EM) environment in the earth, we detected electric pulses originating from the ground. The intensity of the electric pulses detected above the ground was weaker than those in the earth. There were clear lower frequency cutoffs in the spectra suggesting the existence of a kind of horizontal wave‐guide in the earth and the propagation of EM waves there. The estimated scale depth of the bottom conductive boundary of the wave‐guide is consistent with the result obtained from geomagnetic field investigations. The detected electric pulse swarms provided important images of EM wave behavior in the earth.

[1]  T. Nagao,et al.  Co‐seismic geoelectric potential changes observed in Japan , 2000 .

[2]  Masashi Hayakawa,et al.  Atmospheric and ionospheric electromagnetic phenomena associated with earthquakes , 1999 .

[3]  Nicholas V. Sarlis,et al.  INTERCONNECTION OF DEFECT PARAMETERS AND STRESS-INDUCED ELECTRIC SIGNALS IN IONIC CRYSTALS , 1999 .

[4]  H. Matsumoto,et al.  A model experiment of electromagnetic wave propagation over long distances using waveguide terminology , 1997 .

[5]  Y. Fujinawa,et al.  Experiments to Locate Sources of Earthquake-related VLF Electromagnetic Signals , 1997 .

[6]  早川 正士,et al.  Electromagnetic phenomena related to earthquake prediction , 1994 .

[7]  M. S. Lazaridou,et al.  Latest aspects of earthquake prediction in Greece based on seismic electric signals, II☆ , 1993 .

[8]  Y. Fujinawa,et al.  Emission of electromagnetic radiation preceding the Ito seismic swarm of 1989 , 1990, Nature.

[9]  W. Daily,et al.  Evidence of electro-seismic phenomena , 1989 .

[10]  Kozo Takahashi,et al.  Tomography of seismo-radio wave source regions for predicting imminent earthquakes , 1989 .

[11]  N. Nikiforova,et al.  Studies of electromagnetic emission of seismotectonic origin in the Kirghiz S.S.R. , 1989 .

[12]  P. Varotsos,et al.  Physical properties of the variations of the electric field of the earth preceding earthquakes, I , 1984 .

[13]  M. Gokhberg,et al.  Experimental measurement of electromagnetic emissions possibly related to earthquakes in Japan , 1982 .

[14]  T. R. Meyer,et al.  Radio emission associated with rock fracture: Possible application to the Great Chilean Earthquake of May 22, 1960 , 1982 .

[15]  Michiko Yamashita,et al.  Propagation of tweek atmospherics , 1978 .

[16]  R. Barr.  Multimode Propagation in the Earth-Ionosphere Waveguide , 1974 .

[17]  T. Rikitake.  Global electrical conductivity of the earth , 1973 .

[18]  D. Jones,et al.  Observations on the Propagation Constant of the EarthIonosphere Waveguide in the Frequency Band 8 c/s to 16 kc/s† , 1966 .

[19]  H. A. Wheeler,et al.  Radio-wave propagation in the earth's crust , 1961 .