GNGTS 2021 - Atti del 39° Convegno Nazionale

GNGTS 2021 S essione 2.1 194 between the earthquake event ( EQ ) and electron burst event ( EB ). This is indicated by Σ {EQ;EB} (EQ × EB) after Fidani (2015). This approach was performed considering L -shells at different altitudes above earthquake epicenters from –600 km up to 3,200 km in increments of 100 km. A correlation peak between strong earthquakes and particle bursts over more than 16 years of data appeared only from the first electron energy E 1 , detected by the vertical telescope (Fidani 2015). Whereas, correlation peaks did not appear from other electron energy channels utilizing vertical telescopes or from any electron energy channels utilizing horizontal or Omni-directional telescopes. A correlation peak at Δt of 2 - 3 hours started to be significant when considering interaction altitudes above 1,400 km and maximized for 2,200 km, see Figure 1. Correlations were maximized by using earthquake magnitudes M ≥ 6 downloaded at the link http://neic. usgs.gov/neis/epic/epic.html, located in both the Indonesian and the Philippine Regions, having 90° to 150° longitudes, with few events in South America. The electron bursts were detected high offshore of the USA and the South America West Coasts, at longitudes between 200° and 280°. These different positions between earthquakes and electrons were associated in a causal way, due to the fact that electrons drift eastwards and the earthquake positions were located west of the electron burst detection positions (Fidani, 2020). In conclusion, if the disturbances which caused electron precipitations from inner radiation belts occurred above the earthquake epicenters in the ionosphere, they most likely anticipated the earthquake times by 4 - 6.5 hours. For what concerns electromagnetic observations made by instruments on the Earth’s surface, differently from the satellites they are able to monitor small portions of the ground. Then, ground electromagnetic monitoring allows monitoring reduced number of strong earthquakes even in a highly seismic zone, thus making the calculation of correlations a very long-term goal. Only when moderate magnitude earthquakes are considered, a statistical correlation is currently calculated Fig. 1 - The volume representation where the forecasting model can be tested is delimited by the product among the geographical coordinates of earthquakes and electron bursts and the time of observations. V T , V A , and V P are all discontinuous volumes in time as the electron analysis is suitable for earthquake forecasting when the solar activity is very low. Moreover, the alarm duration is one hour. V T and V A cover the entire Indonesian and The Philippine areas, V P covers the different geographical areas on the western North American and South American coasts.