The Red Sismológica Nacional said that the depth, just 15 kilometers (a bit more than 9 miles), suggested the quake was the result of movement in a local fault. The Red estimated the magnitude at 4.1
The Laboratorio de Ingeniería Sísmica Instituto de Investigaciones en Ingeniería, also at the Universidad de Costa Rica, said the magnitude was 4.0. Either estimate makes the quake among the strongest in recent weeks.
The Laboratorio said that sensing devices at the university’s facility in Turrialba and the Hospital William Allen there registered an intensity of IV on the 12-point Mercalli scale. That means the quake was moderate with widows rattling and some ground movement and some small objects falling.
The epicenter was listed as four kilometers (2.5 miles) north northwest of Tres Equis de Turrialba. The quake was felt just barely in San José, but some points in the province of Limón experienced a jolt just a bit less than that in Turrialba. Sensors said that the quake was felt as far south as San Isidro de El General.