A magnitude 3.9 earthquake struck about 10 kilometers off the coast of Santa Rosalía in the Gulf of California at 3:47 p.m. on Sunday, shaking residents across the municipal seat of Mulegé. Mexico’s National Seismological Service (SSN) recorded the quake at a depth of roughly 10 kilometers beneath the sea floor.
Residents in the Mesa Francia neighborhood evacuated their homes after feeling the tremor. Reports on social media and WhatsApp groups described an unusually loud subterranean rumble accompanying the shaking, which spread alarm through the small port town.
No Injuries or Damage Reported
Mulegé municipality president Edith Aguilar Villavicencio confirmed Sunday evening that no injuries or significant structural damage had been reported. As a precaution, Civil Protection, the Fire Department, and the Municipal Civil Protection Council were placed on standby to respond to any follow-up reports.
No tsunami warning was issued following the undersea tremor. Santa Rosalía sits directly on the Gulf of California coastline, about 60 kilometers southeast of the town of Mulegé along Highway 1.
A Seismically Active Zone
The Gulf of California is one of Mexico’s most seismically active regions. The gulf sits atop a tectonic rift zone where the Baja California peninsula is slowly separating from the Mexican mainland. Since 2024, the Santa Rosalía area has recorded 24 earthquakes of magnitude 4.0 or greater and more than 110 quakes between magnitude 3.0 and 4.0, according to seismic tracking data.
The Mulegé area averages about 67 earthquakes per year of magnitude 3.0 or above. The strongest quake near Mulegé since 2025 was a magnitude 4.5 event on June 12, 2025. The last major earthquake in the broader region was a magnitude 6.3 on January 19, 2018, centered 79 kilometers north-northeast of Loreto.
Baja California Sur as a whole averages about 85 quakes of magnitude 3.0 or higher each year. The state has recorded at least nine earthquakes above magnitude 7.0 since 1900, occurring roughly every 10 to 15 years on average.
This story was first reported by Colectivo Pericú.