Figure 4
From: Investigation of GIM-TEC disturbances before M ≥ 6.0 inland earthquakes during 2003–2017
Spatial distribution of the occurrence rates of the ionospheric TEC disturbances. (a,b) show the occurrence rates of the ionospheric TEC disturbances from 1 to 5 days before and after the EQs, respectively. (c) shows the difference between (a) and (b). The x-axis is the geographic longitude and the y-axis is the geographic latitude for all of the images. Color of each grid represents the occurrence rate of TEC anomalies, and the black circles denote epicenters.
