RESULTS OF STATISTICAL ANALYSIS OF LF SEISMOGENIC EMISSIONS AS PRECURSORS TO THE EARTHQUAKE AND VOLCANIC ERUPTIONS

Abstract

Since 1980, we have detected impulsive noise bursts of seismogen ic emissions at 82 kHz, 1525 Hz and 36Hz by a multipoint detec tion network around Tokyo region and Izu peninsula. In the ear lier times, this system has recorded EM signals prior to several earthquake events. And they have recorded volcanic eruptions on November 15 and 21, 1986 at Mt. Mihara on Ohshima Island, on July 12, 1989 in Itoh Bay at the Izu peninsula region, and since June in 1991 at Mt.Unzen on the Shimabara peninsula. To obtain a clear explanation of the source mechanizum of these emissions, we were progressing the statistical analysis of these emission charac teristics by data of 29 events in the last five years.