The only magnitude 8.0 or greater earthquake in July-December 1985 happened in the Central Mexico about 300 km Southwest of Mexico City has the following parameters listed in the NEIC PDE: origin time 1985/09/19 13:17, latitude 18.19N, longitude 102.53W, depth 27 km, and M=8.1, F-E Region: 524 - JALISCO, MEXICO.
Mexico 1985