Caribbean Plate
The
Caribbean Plate is an oceanic
tectonic plate underlying
Central America and the
Caribbean Sea off the north coast of
South America.
Roughly 3.2 million square kilometers (1.2 million square miles) in area, the Caribbean Plate borders the
North American Plate, the
South American Plate, and the
Cocos Plate. These borders are hotspots for
seismic activity, including frequent
earthquakes and tremors, occasional
tsunamis, and
volcanic eruptions.
The most remarkable feature of the Caribbean Plate is that it is the only tectonic plate that has no creative ridge associated with it, although it is in motion as measured by
GPS.
The northern boundary with the North American plate is a
transform or strike-slip boundary which runs from the border area of
Belize,
Guatemala, and
Honduras in Central America, eastward through the
Cayman trough on south of the southeast coast of
Cuba, and just north of
Hispaniola,
Puerto Rico, and the
Virgin Islands. Part of the
Puerto Rico Trench, the deepest part of the
Atlantic Ocean (roughly 8,400 meters), lies along this border. The Puerto Rico trench is at a complex transition from the subduction boundary to the south and the transform boundary to the west.
The eastern boundary is a
subduction zone, but since the boundary between the North and South American Plates in the Atlantic is as yet undefined, it is unclear which one, or possibly both, is descending under the Caribbean Plate. Subduction forms the volcanic islands of the
Lesser Antilles island arc from the Virgin Islands in the north to the islands off the coast of
Venezuela in the south. This boundary contains seventeen active volcanoes, most notably
Soufriere Hills on
Montserrat,
Mount Pelée on
Martinique,
La Grande Soufrière on
Guadeloupe,
Soufrière Saint Vincent on
Saint Vincent, and the submarine volcano
Kick-'em-Jenny which lies about 10 km north of
Grenada.
|
Volcanoes of the Caribbean. |
Along the geologically complex southern boundary the Caribbean Plate interacts with the South American Plate forming
Trinidad (on the South American Plate) and
Tobago (on the Caribbean Plate), the southern islands of the
Netherlands Antilles, and other islands off the coast of Venezuela and
Colombia. This boundary is in part the result of transform faulting along with
thrust faulting and some subduction. The rich Venezuelan
petroleum fields possibly result from this complex plate interaction.
The western portion of the plate is occupied by Central America. The Cocos Plate in the
Pacific Ocean is subducted beneath the Caribbean Plate, just off the western coast of Central America. This subduction forms the volcanoes of
Guatemala,
El Salvador,
Nicaragua, and
Costa Rica.
The Caribbean Plate is thought to be a
large igneous province that formed in the Pacific Ocean tens of millions of years ago. As the Atlantic ocean widened, North America and South America were pushed westward, and the Pacific Ocean floor began to subduct under the western edges of the American continents. The Caribbean Plate is thicker and lay higher than the rest of the Pacific Ocean floor, and instead overrode the Atlantic Ocean floor, moving eastward relative to North America and South America, and, with the formation of the
Isthmus of Panama 2–3 million years ago, ultimately losing its connection to the Pacific.
There is some speculation that the westward motion of the South American Plate may have forced the Caribbean and
Scotia Plates at its northern and southern ends respectively to squeeze around it. Both share a similar shape and are being subducted along their eastern boundary.[
1]
*
List of tectonic plates*
NOAA Ocean Explorer*
Caribbean Plate formation PDF file
