The magnitude-8.1 earthquake that hit Chiapas, Mexico, on Sept. 7 was felt by as many as 50 million people as far away as Guatemala. It left 2 million people without electricity and destroyed buildings in the states of Oaxaca, Chiapas and Tabasco. Amir Gilani and Tsutomu Nifuki—from San Francisco-based Miyamoto International, a structural engineering company investigating the damage—cited out-of-plane failure of unreinforced masonry walls for the collapse of many homes, apartment buildings and public buildings. In a statement, they credited the seismic alert system, installed after the 1985 Mexico City earthquake, with keeping down the number of fatalities. They also cited the fact that the epicenter was offshore and far from densely populated areas.
Alerts Reduce Toll of Mexico Quake
September 13, 2017