GNGTS 2017 - 36° Convegno Nazionale

312 GNGTS 2017 S essione 2.1 Regarding the correlations plots reported in past publications (Fidani, 2015, 2016), an anonymous referee observed that the electron bursts reported a few hours before strong earthquakes in Indonesia are always associated by a minimum around the time of the earthquake, see Fig. 2. This decrease in the curves is of the same order or even greater than the electron bursts at low altitudes. This observational feature was consistent with the decrease of the VLF wave and electron precipitation activity reported in previous studies (Anagnostopoulos et al. , 2012). This minimum appears for each altitude projection and is between -1 and -2 hours, which means that the minimum in correlation occurs when electron bursts follow between 1 and 2 hours strong earthquakes. Therefore, a low electron bursts number seems to be observed between 1 and 2 hours after strong earthquakes. This interesting observation, however, was not so significant as 2 - 3 hours peak. Even if the correlation peak of 1 - 2 hours after earthquakes was of the same magnitude or even greater than the peak of 2 - 3 hours, significance of both peaks was low for those altitude projections. Fig. 1 - The statistical correlation between strong earthquakes occurred in Indonesia and electron burst recorded by NOAA-15 satellite is reproduced here using binnings of 0.5,1.0 and 2.0 hours. Fig. 2 - The statistical correlations between strong earthquakes occurred in Indonesia and electron burst recorded by NOAA-15 satellite reproduced for earthquake altitude projections of 1000, 1200, 1400, 1600, 1800 and 2000 km. Minimum correlation peaks of electron burst observed about 1 - 2 hours after strong earthquake was mainly evident for earthquake projections of 1200, 1400 and 1600 km.