January 19th, 2013 (InsideCostaRica.com) A pair of earthquakes, one measuring 4.6 and the other 4.1 on the Richter scale, shook Costa Ricans last night. Dozens of residents immediately reported the earthquakes via social media to the National Volcanology and Seismology Observatory and the National Seismology Network.
According to the National Seismology Network, the first quake, measuring 4.6 magnitude, occurred at 7:50 pm. The epicenter was located southwest of Samara, in Guanacaste, at 11 kilometers of depth. It was felt in the entire Osa Peninsula.
The second quake was reported at 8:21 pm, with a magnitude of 4.1 on the Richter scale, and its epicenter was located southwest of Quepos. Both earthquakes were caused by subduction of the Cocos plate.