The Gulf of Mexico
The Gulf of Mexico is almost enclosed by parts of North America. The broad continental shelves to the north and south of the deep central basin are rich in oil deposits.
Circulation is weak, and the water becomes more salty as it is heated up. Inflows from rivers and the Caribbean are balanced by an outflow of warm, salty water—the beginnings of the Gulf Stream—via the Straits of Florida to the east. This channel runs between two limestone plateaus—the Florida peninsula, above sea level to the north, and the Bahamas, a submerged plateau topped by low-lying islands to the south. The coasts of the Gulf are affected by powerful hurricanes in the late summer and fall.