Puerto Rico trench
Coordinates: 19°50′9″N 66°45′16″W / 19.83583°N 66.75444°W
The Puerto Rico Trench is located on the boundary between the Caribbean Sea and the Atlantic Ocean. The oceanic trench is associated with a complex transition between the Lesser Antilles subduction zone to the south and the major transform fault zone or plate boundary, which extends west between Cuba and Hispaniola through the Cayman Trench to the coast of Central America. The trench is 800 kilometres (497 mi) long and has a maximum depth of 8,648 metres (28,373 ft) or 5.373 miles at Milwaukee Deep, which is the deepest point in the Atlantic Ocean and the deepest point not in the Pacific Ocean.
Scientific studies have concluded that an earthquake occurring along this fault zone could generate a significant tsunami. The island of Puerto Rico which lies immediately to the south of the fault zone and the trench, suffered a destructive tsunami soon after the 1918 San Fermín earthquake.
The Puerto Rico Trench is located at a boundary between two plates that pass each other along a transform boundary with only a small component of subduction. The Caribbean Plate is moving to the east while the North American Plate is moving to the west. The North American Plate is being subducted by the Caribbean Plate obliquely at the trench while to the southeast, the South American Plate is being more directly subducted along the Lesser Antilles subduction zone. This subduction zone explains the presence of active volcanoes over the southeastern part of the Caribbean Sea. Volcanic activity is frequent along the island arc southeast from Puerto Rico to the coast of South America.
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