Probability of the Occurrence of Two Significant Earthquakes on the Same Date (of Different Years) Striking the Same Site: The Mexico City Case

摘要

On the afternoon of 19 September 2017, just a couple of hours after an earthquake drill, an intense M-w 7.1, intermediate-depth, normal-fault earthquake struck Mexico City and neighboring states causing destruction and 369 deaths. This earthquake occurred on exactly the same date as the well-known 1985 M(w)8.1 subduction earthquake that also struck Mexico City causing severe damage, structure collapses and more than 10,000 deaths. There was a difference of similar to 6 hrs between the hours of these historical seismic events; the 1985 event occurred at 7:17 (CST), and the 2017 event at 13:14 (CDT).