ONE earthquake struck in the northand a second in the central Pacific coastMonday morning, rattling furniture andjiggling things on shelves from the northwesternprovince of Guanacaste to theSouthern Zone.The first struck in Guanacaste, 90kilometers west of Playa Tamarindo, at9:25 a.m. It measured 4.3 on the Richterscale with an epicenter that was 10 kmdeep, according to the Volcanological andSeismological Observatory of Costa Rica(OVSICORI), based at the UniversidadNacional (UNA).The second quake struck approximatelytwo hours later in the central Pacificzone, 25 km southwest of Jacó Beach. Itclocked in at two different magnitudeswith Costa Rica’s two earthquake detectionagencies, OVSICORI and theNational Seismological Network (RSN) atthe University of Costa Rica.It was magnitude 4.3 according toOVSICORI, and 4.9 according to RSN. Itsepicenter was 22 km deep according toOVSICORI and less than 10 km deepaccording to RSN. The difference, scientistsat each institution explained to The TicoTimes Monday, is in the location of the sensorsand the interpretation of the data.The second quake was felt throughoutthe Central Valley and the Pacific slope,and caused slight damage such as dishesfalling off shelves, the seismological networkreported.