Two-dimensional principal component analysis (2DPCA) were used to examine the ionospheric total electron content (TEC) data during the time period from 00:00 on 11 April to 00: 25 on 16 April (UT) 2016, which were 5 days before the Mw=7.3 Kyushu earthquake at 00:25:06 on 16 April 2016 (UT) with the epicenter (32.782°N, 130.726°E) and the depth of 10km. From the analysis result of 2DPCA, a TEC precursor was found localized nearby the epicenter during the time period from 06:20 to 06:25 on 11 April 2016 (UT) with the duration time of at least 5 minutes. The past studied by other researchers discusses potential reasons for TEC anomaly due to large earthquake mainly including radon gas release, P-type semiconductor effect (electric fields) and shock-acoustic waves for the TEC anomaly However, the possible reasons of the TEC anomaly related to this earthquake should be radon gas release and P-type semiconductor effects before the earthquake. Shock-acoustic wave was impossible reason because before this earthquake, large ground surface vibrations that formed shock-acoustic waves were not detected.
Two-dimensional principal component analysis (2DPCA) Ionospheric total electron content (TEC) Kyushu earthquake Radon gas release P-type semiconductor effects Shock-acoustic waves Ground surface vibrations
Journal Section | Physics |
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Authors | |
Publication Date | December 11, 2017 |
Published in Issue | Year 2017 Volume: 30 Issue: 4 |