The Laboratorio de Ingenieria Sismica reported a 4.0 magnitude earthquake took place 12.4 kilometers southeast of Pavon de Golfito at 4:46 p.m. Sunday.
It was the largest of four quakes that took place Sunday.
The Laboratorio estimated the epicenter a few miles inland on the border with Panamá. The Observatorio Vulcanológico y Sismológico de Costa Rica, also based at the Universidad de Costa Rica, estimated the quake at a 4.4 magnitude and placed the estimated epicenter offshore in the Pacific.
There also was a 3.5 magnitude quake Sunday at 12:02 p.m. 24 kilometers northwest of Zapotillal de Santa Cruz in northwest Costa Rica, said the Obervatorio. Other Sunday quakes were less than 3.0, according to the Observatorio. However, the Laboratorio estimated one at 5:01 a.m. about 11 kilometers (about 7 miles) south southeast of Orosi de Paraiso at 3.0 and one at 4:13 a.m. in Santo Domingio de Heredia at 3.2 magnitude.
Both agencies have revised their reporting policies, and the Laboratorio now provides real time emails of earthquakes that appear to have been felt by humans. The Observatorio has updated its Web page with running information on quakes.