On Monday, October 13^th after 9:30 pm, the Observatory of Seismology and Volcanology in Costa Rica (Spanish acronym: OVSICORI) of the National University and the National Seismology Network (Spanish initials: RSN) 0f the University of Costa Rica reported three seismic disturbances. The first one occurred at 9:31 pm, the second at 9:42 pm and the third at 9:51 pm. The latter quake was strongly felt across the country even though the epicenter was off the coast of Nicaragua and El Salvador.

The RSN located the 9:31 pm earthquake 37 km southwest of Bahia Ballena in the Osa Peninsula. That earth tremor was measured at 5.3 Mw (momentum magnitude scale) and its epicenter detected at a depth of 10 km. Ten minutes later, a 3.3 seism was detected 10 km west of Pavon in the Golfito canton near the southern border with Panama. The strongest earthquake was felt at 9:51 pm, and its epicenter was located off the Pacific coast of Nicaragua and El Salvador.

Initial reports of the 9:51 pm earthquake suggested an epicenter near the Gold Coast beaches of Guanacaste, where residents who were already in bed stumbled out of their homes in their sleepwear as objects fell from shelves and shifted around in closets and cupboards.

Tsunami alerts were issued by emergency management officials in El Salvador and Nicaragua, but they were later discarded. At least one casualty was reported by La Prensa Gráfica, a national newspaper in El Salvador; the decedent was an adult male who was crushed by a light pole in the community of San Miguel. Rescuers from the Red Cross and the Lifesaving Command were deployed to coastal communities in El Salvador. Emergency officials in Nicaragua also activated earthquake response protocols, although no casualties were reported as of 11:40 pm local time.

The 9:51 pm earthquake was measured at 7.3 Mw, and its epicenter was off the Usulutan coastline at a depth of 72 kilometers. Social media reports from park rangers in Cocos Island, the inspiration for next year’s Jurassic World cinematic blockbuster, indicated that the quake was strongly felt and prompted a cacophony among the abundant wildlife in that national park. Other social media reports arrived from Guanacaste and down towards the Central Valley and beyond. Although Costa Rica is known as a seismic nation, residents in the Pacific coast uneasily returned to their beds as they wondered if other geologic events would disrupt their sleep.