Summary: | 碩士 === 國立中央大學 === 太空科學研究所 === 103 === Evidence of the seismo-ionospheric precursor (SIP) is reported by statistically
investigating the relationship between the total electron content
(TEC) in global ionosphere map (GIM) and earthquake of Circum-Pacific
seismic zone during 1999-2014. This paper was studied the earthquakes
occurred in Taiwan, Sumatra, South America, Japan, and Central America.
A median-based method together with the z test is employed to examine
the TEC variations 30 days before and after the earthquake. The receiver
operating characteristic (ROC) curve is then used to evaluate the efficiency
of TEC for predicting earthquakes during a specified time period. It is
found that the TEC significantly decreases 1600-2000 LT in 2-4 days before
the 129 M≥5.5 earthquake in Taiwan. The statistical result in Sumatra
shows that TEC reductions appeared 0200-0600 LT 1-2 days before 153 M
6.0 earthquakes. 151 M 6.0 earthquakes in South America was studied
and TEC significantly decreases 1800-2300 LT 3-5 days before earthquakes.
An abnormal increase was found 1-4 days before 220 M 6.0
earthquakes in Japan. The TEC in Central America decrease 10-15 days
before 122 M6.0 earthquakes
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