Rocky layers weakened destructive force of the earthquake

What President Laura Chinchilla called “miraculous” when she witnessed the moderate earthquake damage in Nicoya, has a scientific explanation.

What was the reason that the second strongest earthquake in the history of the country of 7.6 degrees – caused only minor damage?

Wilfredo Rojas, a geologist at the National Seismological Network (RSN), explained that several factors, such as the depth of the quake and the bedrock beneath the earth’s crust that allowed to mitigate the destructive force of the waves.

The Volcanological and Seismological Observatory of Costa Rica (OVSICORI) located the quake 20 miles south of Samara, Nicoya, at a depth between 15 and 40 kilometers. The origin was by the subduction of the Cocos plate in the Caribbean.

Rojas said the waves had walked several kilometers from the base to the surface, so it became weaker as they advanced from the bedrock that characterizes the Nicoya Peninsula, which served as a barrier to the energy that was released in that time.

The geologist said the Cocos plate, had a subduction in the Caribbean plate at an angle of 35 degrees at the time of the break, which allowed this occurredtowards the bottom of the earth and not to the surface.

There was no perceptibletsunami because the coup was not direction toward the water. Thus, rocky soil, the depth and angle of inclination allowed breakpoint avoid a catastrophe.

Wilfredo Rojas also pointed out that the depth of 15 kilometers, the earthquakeonly moved three meters a large mass of an area of 60 km by 35 km, headingnortheast.

He and two other geologists visited yesterday RSN six points along the Pacific coast, to measure the lifting of the surface by the quake. Higher elevations werein Playa Carrillo (50 centimeters) and Pelada beach (75).

Experts noted that Garza beach there was liquefaction: shoot in the sand jet of water from the bottom.

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