著者

Guan Huaping Liu Guiping

出版者

独立行政法人防災科学技術研究所

雑誌

防災科学技術研究所研究資料 (ISSN:0917057X)

巻号頁・発行日

vol.166, pp.303-314, 1995-03-31

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Electromagnetic radiation observation have been conducted in China since the Tangshan earthquake in July 28, 1976. Up to now, 130 observatories have been established. The present observing frequency ranges are ultra-low frequency 0.01-20 Hz and point frequency from 10^3 to 10^4 Hz. In the past 20 years, more than 40 earthquakes with magnitude larger than 5.0 occurred in and around the observation network. By analyzing the electromagneticanomalies, it was demonstrated that the detection distance of the anomaly is related with the magnitude, the lasting time of anomalies are from several seconds to several tens days, and no electromagnetic radiation was observed coseismicaly.