Overview
- A sequence of shallow, offshore earthquakes began Wednesday, Sept. 2, led by a 5.5 event that the Servicio Sismológico Nacional located roughly 145 km southwest of Huixtla at about 10 km depth.
- The Sistema de Alerta Sísmica Mexicano detected the main shock but did not issue a public alert because its rapid automatic energy estimates did not pass pre‑set activation thresholds.
- SSN bulletins logged several smaller quakes over Sept. 2–3 with magnitudes between about 3.7 and 4.3 and focal depths near 10 km, all centered 120–160 km off the Chiapas coast.
- State and national Protección Civil teams report no injuries or damage and say they have kept preventive inspections and round‑the‑clock surveillance of coastal municipalities.
- Chiapas sits where the Cocos, North American and Caribbean plates interact, so officials stress that distant, shallow epicenters often go mostly unperceived on land and reinforce the need to follow the planned national drill on Sept. 19.