A 4.0-magnitude quake struck near Crucecita, Oaxaca, on May 12. Residents felt strong tremors; seismic service reports no significant damage or injuries.
At 9:04 a.m. local time on Monday, May 12, 2025, a moderate magnitude-4.0 earthquake struck 19.4 km northwest of Crucecita, in the southern Mexican state of Oaxaca. The Servicio Sismológico Nacional (SSN) recorded the event at a depth of 49.3 km, noting that it was part of ongoing tectonic activity along the regional subduction zone.
Residents across the Costa region—from Salina Cruz to Huatulco—reported feeling strong but brief jolts. In Crucecita itself, chairs slid across tiled floors and hanging light fixtures swayed visibly. “It felt like a sudden push, then everything settled within seconds,” said local teacher Martha González. No structural damage has been reported in Crucecita or nearby communities, according to municipal authorities.
Oaxaca sits atop the convergent boundary where the Cocos Plate dives beneath the North American Plate, a setting that frequently generates seismic events ranging from low-magnitude tremors to major quakes above 8.0. While the state’s building code requires earthquake-resilient construction—strengthened after the devastating 8.2-magnitude Chiapas quake of 2017—many older structures remain vulnerable. This morning’s quake did not trigger any known collapses or injuries.
The SSN immediately dispatched mobile seismic stations to the epicentral area to refine the event’s parameters and check for aftershocks. By mid-afternoon, no significant aftershocks had been detected. SSN Director Luis Arias emphasized that the depth and magnitude suggest a low probability of surface faulting or landslides, although monitoring will continue. “This is a routine seismic occurrence for this region,” he said.
Local emergency services conducted a precautionary sweep of schools, clinics and government offices in San Pedro Pochutla and Santa María Huatulco, where the shaking was most perceptible. Oaxaca’s Civil Protection Agency urged residents to review earthquake-safety protocols—such as securing heavy furniture, familiarizing themselves with evacuation routes and preparing emergency kits—especially with the region still in its rainy season, which can compound landslide risk.
Infrastructure inspections were also carried out on the Trans-Isthmus Highway (Federal Highway 185D), the main artery connecting coastal towns. Early checks by the Secretariat of Communications and Transportation found no road damage or bridge instability. The Oaxaca state power utility reported no outages, while telecommunication providers confirmed that cell and internet services remained fully operational.
Seismologists note that the Oaxaca coastal region often experiences a flurry of smaller quakes in the days following moderate events. Jorge Mendoza, a geophysicist at the National Autonomous University of Mexico (UNAM), said that while most aftershocks are too weak to be felt, some could reach magnitudes up to 3.5. He advised residents to remain alert but not alarmed: “Aftershock sequences are normal and pose minimal additional risk if buildings follow code”.
Tourism officials in Huatulco—where beaches and resorts draw both domestic and international visitors—reported that most tourists were unaware of the quake, as many were still asleep. “Our hotels are designed with seismic standards; guests are safe,” said Fernando López, head of the local tourism board. Hotels performed internal checks and found no impact on facilities, he added.
While today’s tremor passed without major incident, Oaxaca’s broader seismic context remains a concern. In 2017, the magnitude-7.1 Puebla–Morelos quake and the Chiapas event claimed over 100 lives statewide and caused widespread damage. Since then, investment in seismic early-warning systems (SASMEX) and stricter building inspections have improved preparedness. The national Seismic Alert System successfully issued alerts this morning for communities more than 100 km away from the epicenter.
Meanwhile, community groups in more remote villages—where adobe homes and unreinforced masonry structures prevail—are being offered voluntary retrofitting workshops by the National Center for Disaster Prevention (CENAPRED). These efforts aim to bolster resilience ahead of the July–September hurricane season, when heavy rains can trigger secondary hazards such as landslides and mudflows.
As the day closes, the SSN has downgraded the event to a training-level alert and continues to feed data into its national catalog. Residents in Oaxaca’s coastal corridor are breathing easier, but authorities reinforce the message that Mexico’s Pacific Ring of Fire demands constant vigilance. “Preparedness is the key,” said Civil Protection Chief María Elena Vázquez. “Every shake, however small, is a reminder.”
