Costa Rica's west coast lies along a subduction zone where one mobile plate in Earth's crust –
the
Cocos Plate – is plunging beneath the Caribbean Plate. This action has
formed the Middle American Trench, which parallels the coastline
offshore. This subduction zone also is responsible for raising a string
of volcanoes that runs up the country's interior.
Subduction zones are responsible for the most violent earthquakes the planet's restless crust delivers, researchers say. The reason: The surface areas involved in subduction quakes, where the two plates are in contact with each other as the fault slants downward toward the Earth's interior, typically are far larger that the surface areas involved in the rupture of so-called strike-slip faults, such as California's San Andreas Fault. When a portion of a subduction zone locks up, it takes larger amounts of accumulated strain to overcome the friction locking the segment.
Indeed, during the past decade, researchers studying the seismic history of the Nicoya Peninsula have been cautioning that the region was due for another major quake soon.
The Nicoya Peninsula last saw an earthquake of comparable magnitude in 1950, according to Jeff Marshall, a geologist at California State Polytechnic University in Pomona. That quake registered a magnitude of 7.7 and led to dozens of casualties, heavy damage to buildings, up to seven feet of uplift along the peninsula's coastline, and soils in some regions that in effect liquefied with the shaking. That quake's epicenter appears to have been fairly close to the epicenter of Wednesday's quake.
So in a nutshell and I do not want to make lite of this. It was a deep earthquake which made for less damage, it could of been catastrophic. Only 1 death due to a heart attack , no tsunami, no volcano eruptions and hopefully this will be it for another 50 years or so....
Subduction zones are responsible for the most violent earthquakes the planet's restless crust delivers, researchers say. The reason: The surface areas involved in subduction quakes, where the two plates are in contact with each other as the fault slants downward toward the Earth's interior, typically are far larger that the surface areas involved in the rupture of so-called strike-slip faults, such as California's San Andreas Fault. When a portion of a subduction zone locks up, it takes larger amounts of accumulated strain to overcome the friction locking the segment.
Indeed, during the past decade, researchers studying the seismic history of the Nicoya Peninsula have been cautioning that the region was due for another major quake soon.
The Nicoya Peninsula last saw an earthquake of comparable magnitude in 1950, according to Jeff Marshall, a geologist at California State Polytechnic University in Pomona. That quake registered a magnitude of 7.7 and led to dozens of casualties, heavy damage to buildings, up to seven feet of uplift along the peninsula's coastline, and soils in some regions that in effect liquefied with the shaking. That quake's epicenter appears to have been fairly close to the epicenter of Wednesday's quake.
So in a nutshell and I do not want to make lite of this. It was a deep earthquake which made for less damage, it could of been catastrophic. Only 1 death due to a heart attack , no tsunami, no volcano eruptions and hopefully this will be it for another 50 years or so....
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