The National Seismological Service (SSN, for its acronym in Spanish), reported that up to now there have been 39 aftershocks from the earthquake that occurred on September 19 and 6,510 from the earthquake on September 7.
“Aftershocks until 7:30 am on October 5, 2017: 39 aftershocks of the Seismic M 7.1 Puebla-Morelos; 6510 aftershocks of the earthquake M 8.2 Gulf of Tehuantepec”, published in its Twitter account @SSNMexico.
Réplicas hasta las 7:30 am del 5/10/2017
0039 Réplicas del Sismo M 7.1 Puebla-Morelos
6510 Réplicas del Sismo M 8.2 golfo de Tehuantepec
— Sismológico Nacional (@SSNMexico) October 5, 2017
According to the organism, when an earthquake of considerable magnitude occurs the rocks that are near the zone of rupture undergo a rearrangement, which generates a series of tremors in the zone called aftershocks.
It points out that the number of aftershocks can vary from a few to hundreds of events in the coming days or weeks of the main tremor.
The occurrence of tremors in the states of Chiapas and Oaxaca is frequent and to date there are no scientific techniques anywhere in the world that can determine when or where an earthquake will occur, nor can we know how large it will be or what effects it will have on the population, it says.