| 摘要 |
<p>PROBLEM TO BE SOLVED: To transmits low frequency earthquake electromagnetic field signals, local characteristic value signals and improved local characteristic value signals of a plurality of observing stations to a base station, determine delay time, half-value width and main characteristic value signal of an electromagnetic field signal from the correlation function of each station, and estimate the generating time, place and magnitude of an earthquake from them with high precision. SOLUTION: In a plurality of observing stations, the electromagnetic field signal accompanying a minute breakage of earth crust is observed by a sensor 1 and made into an earthquake electromagnetic signal free from noise by a local discriminating part 3, and local characteristic value and improved local characteristic value are formed by a local characteristic value calculating part 4. A transmitting part 5 transmits them to the receiving part 6 of a base station, a correlation processing part 7 finds the delay time and half-value width from the correlation function between the data of each observing station, and a tomographic part 8 finds the spatial distribution and extension of an earthquake electromagnetic field signal generating source. A main station discriminating part 9 extracts the electromagnetic field signal within an arrival allowable time width from the delay time, and a main station characteristic value calculating part 10 finds the main station characteristic value. A three-factor estimating part 11 synthetically estimates the earthquake generating time, generating place, and magnitude from them.</p> |
