Atlantic Ocean

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Atlantic Ocean Body of wafer extending from the Arctic to the Antarctic, separating North and South America (W) from Europe and Africa (E); area c.82 217 000 sq km/ 31 700 000 sq mi; average depth 3700 m/12 000 ft; maximum depth, Puerto Rico Trench, 8648 m/28 372 ft; principal arms (W), Labrador Sea, Gulf of Mexico, Caribbean Sea; (E), North Sea, Baltic Sea, Mediterranean and Black Sea, Bay of Biscay, Gulf of Guinea; (S), Weddell Sea; continental shelf narrow off-coast of Africa and Spain, broader in NM/ Europe and off Americas; (S) shaped, submarine Mid-Atlantic Ridge between Iceland and the Antarctic Circle, center of earthquake and volcanic activity; major surface circulation, clockwise in N, counter-clockwise in S; main currents include the Gulf Stream (N Atlantic Drift), and the N Equatorial, Canary, S Equatorial, Brazil, Benguela, and Equatorial Counter Currents. >> current (oceanography); plate tectonics

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