Overview

• SSN logged multiple low-to-moderate events on September 10–11, including M4.5 off Puerto Vallarta and M4.0 near Huixtla and Salina Cruz, plus M3.4 south of Coalcomán and M3.7 near Tesistán, with no reported damage.
• SASMEX sirens were not triggered because the quakes did not reach the magnitude–distance criteria required for public alerts.
• UNAM plans at least 20 new broadband stations by late 2025 and the first half of 2026, with a commitment to deploy about 38 more in the following two years, including several in Michoacán.
• The SSN already operates more than 100 stations, including roughly 65 broadband sensors, alongside Valley of Mexico and delegational networks that transmit data to the center in real time.
• Resilience and research backstop the system through a mirror monitoring center in Pachuca for continuity and a UNAM shake table that informs building codes, as experts reiterate September is not uniquely seismic.