Overview
- The strongest quake was a magnitude 5.5 recorded on Wednesday, Sept. 2, with an epicenter about 145 km southwest of Huixtla and a focal depth near 10 km, according to the Servicio Sismológico Nacional.
- SASMEX sensors detected the main event but did not trigger a public alert because the system’s automated early energy estimate did not exceed pre‑set activation thresholds for connected cities.
- Chiapas authorities and civil protection teams kept preventive monitoring after the shocks and reported no injuries, no structural damage and no tsunami warning.
- The SSN logged multiple smaller shallow quakes that day off the Chiapas coast, reflecting the region’s active plate boundary where the Cocos, North American and Caribbean plates interact.
- Local experts urged expanding seismic station coverage—Chiapas currently has about four SSN stations versus roughly 11 in neighboring Oaxaca—to improve location accuracy, speed warnings, and inform upcoming preparedness exercises such as the Sept. 19 national drill.