The analysis of unexpected ionospheric phases before large earthquakes is one of the cutting-edge issues in earthquake prediction studies. Ionospheric TEC data were analyzed by short-time Fourier transform and a classic running median to detect abnormalities before the M_w 7.3 Iran–Iraq earthquake on November 12, 2017. The results showed clear positive anomalies 8–9 d before the earthquake as an earthquake precursor due to quiet space weather, local dispersion, and proximity to the epicenter.

In this study, TEC and positional variations have been examined seperately regarding the earthquake, which occurred in the Aegean Sea. Then The correlation of the said ionospheric variation with the positional variation has been investigated; it can be said definitely that it is a seismic origin anomaly; it is believed that upper air, geophysical, and geological data are required.