The Cocos Plate is a tectonic plate beneath the Pacific Ocean off the west coast of Central America. It is named for Cocos Island, which is the only emergent island of the plate.
The Cocos Plate is a relatively small sized, triangular-shaped oceanic plate, located beneath the Pacific Ocean, off the west coast of Central America. It is named for Cocos Island, which is the only emergent island of the plate.
Approximately 23 million years ago the ancient oceanic Farallon Plate broke into two pieces, creating both the Nazca Plate and the Cocos Plate. The Cocos Plate then also broke into two pieces, creating the small Rivera Plate.
Map of tectonic plates of the Americas
The Cocos Plate is being subducted under Mexico and Central America. As a result, a belt of volcanoes extends from northern Panama to western Mexico and virtually all of the highest mountains in this belt are volcanic.
These volcanoes are built on thickened crust ;but the principal tectonic process that has affected the landscape is volcanism. These continuous arcs of volcanos are known as:
the Central America Volcanic Arc, which stretches from Guatemala south into El Salvador, Nicaragua, Costa Rica and just past the border into northern Panama
the Trans-Mexican Volcanic Belt, which extends east-west through Mexico
The northern boundary of the plate is the Middle America Trench. The eastern boundary is a transform fault, the Panama Fracture Zone. The southern boundary is a mid-oceanic ridge, the Galapagos Rise. The western boundary is another mid-ocean ridge, the East Pacific Rise.
Subduction beneath the North American Plate, along the Middle American Trench in Mexico, generates large to great earthquakes and sometimes sunamis every 30 - 100 years.