Mexico City has been hit by successive minor earthquakes for the second time in three days.
A 3.2 magnitude quake shook the capital at 2:13 p.m. Thursday, while a weaker 2.4 magnitude quake occurred two minutes later. The epicenter of both quakes, widely reported as “micro-quakes,” was in the borough of Álvaro Obregón, according to the National Seismological Service (SSN).
Fueron 2 microsismos en #CDMX
-14:13 PM / Magnitud 3.2, epicentro a 3km Noreste de la Magdalena Contreras
-14:15 PM / Magnitud 2.4, epicentro a 4km al sur de Álvaro Obregón pic.twitter.com/zoNdP85epS— Manuel Lopez San Martin (@MLopezSanMartin) December 14, 2023
Residents of several Mexico City boroughs including Cuauhtémoc, Benito Juárez, Miguel Hidalgo, Iztapalapa and Iztacalco reported feeling the Thursday afternoon quakes.
The Reforma newspaper said that residents of Álvaro Obregón reported feeling a “strong yank” that lasted around five seconds, presumably during the first, stronger quake.
Mexico City Mayor Martí Batres said on the X social media platform shortly after the quakes that no damage had been reported. Authorities carried out their usual earthquake protocols, including conducting inspections from the vantage point of helicopters.
Reforma reported that residents evacuated some buildings, but Mexico City’s earthquake alarm system wasn’t activated.
The alarm, amplified through loudspeakers situated across the capital, sounds up to a minute before a sufficiently powerful earthquake begins to be felt, but it is dependent on sensors outside the capital. It can give residents a brief window of opportunity to evacuate to the safety of the street and thus avoid the risk of being caught in a building that collapses.
While there are varying definitions of what a microearthquake is, Wikipedia and at least two online dictionaries say that a micro-quake has a magnitude of 2.0 or less. By that definition, the quakes on Thursday wouldn’t qualify as such, although many Mexican media outlets described them as microsismos.
Thursday’s “micro-quakes” followed four on Tuesday, which also had epicenters in Álvaro Obregón.
Eight buildings in the Benito Juárez borough were subsequently evacuated while specialists from the local Construction Safety Institute determined the habitability of each one.
Micro-quakes with epicenters in Mexico City are relatively common, and many – perhaps most with a magnitude of 2.0 or less – are imperceptible.
Thursday’s quakes occurred a week after a 5.7 magnitude temblor with an epicenter in Puebla set off the earthquake alarm in Mexico City. No damage was reported.
The southern state of Chiapas was also affected by seismic activity on Thursday. One quake that occurred just before midday had a magnitude of 5.5, the SSN said. Its epicenter was 135 southeast of Ciudad Hidalgo, Chiapas. No damage was reported.
With reports from Reforma
