(CNN Spanish) — It has trembled again in Mexico on September 19, a date marked by tragedy and fright: three tremors have shaken the country on the same day in 1985, 2017 and now this 2022. The probability that this will be repeated exists but it is very low, according to the scientists, who highlight the importance of opening new lines of research in this regard in order to provide “appropriate” answers.
An earthquake of magnitude 7.6, with an epicenter in Michoacán, was felt strongly in Mexico City this Monday, September 19, 2022, almost an hour after the drill was carried out for the other two large tremors that claimed thousands of lives in the country’s capital, in 1985 and 2017.
Earthquakes are a common phenomenon in Mexico, since the country is located in an area of ”high seismicity”, according to the National Seismological Service (SSN). But after Monday’s shock, the question many are asking is, how likely is it that three earthquakes will occur on the same date? Scientists have answered this.
An “unpleasant coincidence”
“The probability is very low, but it is not impossible,” explained the scientist Víctor Hugo Espíndola, chief analyst of the SSN of the National Autonomous University of Mexico (UNAM), about the relationship that could exist between the three earthquakes with a higher magnitude to 7 on the Richter scale that have occurred on the same day in different years.
“If we see the entire seismic catalog that we have since the early 1900s, we see that they have been repeated for earthquakes greater than 7 in different months, for example we see several in the month of December, several in other months, then certainly the probability of occurring on the same day is very low,” explained the scientist.
Luis Quintanar Robles, a researcher at the Department of Seismology at the UNAM Institute of Geophysics, agreed that there is no scientific certainty that the earthquakes occur on the same day.
“What we can say is that earthquakes generally trigger when there is a release of stress produced in a neighboring area,” Quintanar explained.
Espíndola rather described it as “an unpleasant coincidence” and the National Seismological wrote via Twitter that precisely this coincidence “It deserves to open new lines of scientific research. It must be done seriously and methodically. In science, new questions require appropriate answers.”
On September 19, 1985, an earthquake of magnitude 8.1 caused severe damage to hundreds of buildings in Mexico City and thousands of people lost their lives. 32 years passed without any other earthquake causing deaths and millions of economic losses until September 19, 2017, when Morelos, Puebla, Mexico City, the State of Mexico, Guerrero and Oaxaca felt an earthquake of magnitude 7.1.
The total number of deaths in 2017 was counted in the hundreds (the official figure is 369), while some 250,000 people were affected, more than 180,000 homes were damaged by the two earthquakes and of those, 50,610 had total damage.