By MARK LORENZANA A 7.7 magnitude earthquake shook Mexico on the afternoon of Monday, Sept. 19, just minutes after a nationwide earthquake drill or “simulacro nacional” was held to commemorate the victims of the 1985 and 2017 earthquakes. Mexico’s National Seismological Service reported that the epicenter of the quake was 63 kilometers south of Coalcomán, Michoacán, but it could be