QCOSTARICA – The question is not if, but when, a major earthquake will strike Costa Rica’s Osa Peninsula.
A huge accumulation of energy that has been taking place for 40 years is the simplest explanation to illustrate the reason why a more than 7 magnitude earthquake is expected.
In a nutshell, the Cocos and Nazca plates are getting behind the Panama plate and generating enormous pressure that will be released violently, explained the director of the Observatorio Vulcanológico y Sismológico de Costa Rica (OVISCORI) – Volcanological and Seismological Observatory of Costa Rica – Marino Protti, in the Teletica television program En Profundidad (In Depth).
El próximo lunes les presentaremos un #InformeEspecial ante desastres naturales como sismos y tsunamis.
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Protti explained that it is not possible to know when the event will be, but that it normally responds to cycles of approximately forty years.
The last major event caused by this interaction of plates occurred in April 1983 and is popularly known as the terrermoto de Sábado Santo (Holy Saturday earthquake ), a 7.4 magnitude quake at 8:50 pm, Saturday, April 2, 1983, located 15 km NNE of the city of Golfito at a depth of 26 km.
Read more: 5.3 Earthquake Shakes Osa Peninsula
Protti added that it is a phenomenon similar to the one that caused the Nicoya earthquake in 2012, a 7.6 MW quake on September 5, in the Nicoya Peninsula, 11 kilometers east-southeast of Nicoya.
The OSA earthquake would be similar, but with the difference that, the plates that interacted were those of Cocos and the Caribbean.
Protti also indicated that it is possible that this earthquake is shallower than the one in Nicoya.
Recent earthquakes in Costa Rica
During the past 7 days, Costa Rica was shaken by 2 quakes of magnitude 4.0 or above, 20 quakes between 3.0 and 4.0, and 12 quakes between 2.0 and 3.0. There were also 2 quakes below magnitude 2.0 which people don’t normally feel.
The biggest quake: 4.0 quake North Pacific Ocean, 6 days ago on August 2.
For a complete list & interactive map of the recent earthquakes in Costa Rica visit https://www.volcanodiscovery.com/earthquakes/costarica.html.
Also of interest Anticipating and Monitoring a Large Earthquake in Costa Rica by Researchers: Marino Protti and Victor González.