The Pacific subduction zone has been active over Semana Santa. Four felt quakes took place between April 18 and Sunday.
The Observatorio Vulcanológico y Sismológico de Costa Rica logged these events:
The latest was at 6:49 p.m. Sunday about 6.7 kilometers (4.1 miles) northeast of Puerto Armuelles in Panama. That is a very active area. The magnitude was listed as 4.5
Thursday at 8:45 a.m. a 3.8-magnitude quake took place 9.5 kilometers (5.9 miles) northeast of Grecia.
Tuesday at 6:42 a.m. a 4.1 quake took place 31 kilometers (19 miles) west of Quepos.
And Monday at 9:44 p.m. a 4.3-magnitude quake took place 18 kilometers (11 miles) southeast of Herradura. That was felt in Playa Coyote, Jacó and Paquera.
The denser Cocos plate is pushing under the lighter Caribbean plate on which much of the country rides. Although the Cocos plate is popularly considered to be under the Pacific Ocean, it intrudes inland and the subduction is responsible for the country’s volcanoes and mountains. The visible trench where the western edge of the Caribbean plate meets the Cocos is visible under the Pacific Ocean.
Puerto Armuelles is an active area in part because the Panamá microplate or block is in contact with the Cocos plate there.