Overview
- Mexico’s National Seismological Service reported a magnitude 4.0 quake at 02:21 a.m. west of San Marcos, Guerrero, at 16.813°, -99.553° and 14.7 km depth.
- A second event of magnitude 4.1 was recorded at 03:05 a.m. southeast of Crucecita, Oaxaca, at 15.299°, -95.619° and 16.1 km depth.
- SASMEX did not issue an alert because activation depends on distance and magnitude thresholds, such as magnitude 6 beyond 350 km, magnitude 5 for 350–250 km, and greater than 5 within 250 km.
- Coverage indicates no damage reports, and the SSN notes it will maintain continuous monitoring on January 16, when numerous low‑magnitude microsismos are commonly documented.
- Protección Civil reiterates preparedness guidance, urging people to identify safe zones, stay clear of glass and heavy furniture, avoid elevators, and follow official instructions during any shaking.