Which 1985 earthquake caused catastrophic damage in Mexico City?

The 1985 earthquake that caused catastrophic damage in Mexico City was the 1985 Mexico City earthquake.

The magnitude 8.0 earthquake struck on 19 September 1985, with its rupture zone off Mexico’s Pacific coast near Michoacán. Although the epicenter was hundreds of kilometres from the capital, Mexico City suffered extraordinary damage because parts of the city were built on soft former lake sediments.

Those sediments amplified and prolonged seismic waves, especially in areas with buildings several stories tall. Thousands of structures collapsed, and official death figures were lower than many independent estimates. A magnitude 7.5 aftershock struck the following day.

The disaster prompted major changes in Mexican building codes, emergency planning and civil-society organization. It is distinct from the 2017 Puebla and Chiapas earthquakes, which also affected Mexico but occurred decades later.