The Indian Ocean

The Indian Ocean is the third largest in the world and covers about 20 percent of the Earth's water surface. Its volume is estimated to be about 70,086,000 cubic miles (292,131,000 cubic kilometers).

The Indian Ocean contains many islands. During the prehistoric breakup of the continents, small pieces of continent were left behind in the Indian Ocean as undersea plateaus (high, level land areas). Some of these plateaus rise above the water and form islands, such as the Laccadives. Many other islands, such as Mauritius, are volcanic in origin. On the ocean's eastern border lie the islands of Indonesia; on the western border lie Madagascar, Zanzibar, the Comoros, the Seychelles, the Maldives, and the Nicobar Islands. To the south are the Crozets and the Kerguelen. Coral reefs (undersea walls made from coral skeletons) can be found in areas of the ocean located in the...