Presented by :- shakti patel

Special thanks to :- Jolly sushma

Indian Ocean, body of salt water, covering approximately one-fifth of the total ocean area of

the world. It is the smallest, youngest, and physically most complex of the world’s three

major oceans. It stretches for more than 6,200 miles (10,000 km) between the southern tips of 

Africa and Australia and, without its marginal seas, has an area of about 28,360,000 square

miles (73,440,000 square km). The Indian Ocean’s average depth is 12,990 feet (3,960

metres), and its deepest point, in the Sunda Deep of the Java Trench off the southern coast of Java,

is 24,442 feet (7,450 metres).

The ocean is nearly 10,000 km (6,200 mi) wide at the southern tips of Africa and Australia, and its area is 73,556,000 km² (28,350,000 mi²),[8] including the Red Sea and the Persian Gulf.

The ocean's volume is estimated to be 292,131,000 km³ (70,086,000 mi³). [9] Small islands dot the continental rims. Island nationswithin the ocean are Madagascar (the world's fourth largest island), Comoros, Seychelles, Maldives, 

Mauritius, and Sri Lanka. The archipelago of Indonesia borders the ocean on the east.

The origin and evolution of the Indian Ocean is the most complicated of the three major oceans. Its formation is a consequence of

the breakup, about 150 million years ago, of the southern supercontinent Gondwana (or Gondwanaland); by the movement to the

northeast of the Indian subcontinent (beginning about 125 million years ago),

which began colliding with Eurasia about 50 million years ago; and by the western movement of Africa and separation of

Australia from Antarctica some 53 million years ago. By 36 million years ago, the Indian Ocean had taken on its present

configuration. Although it first opened some 125 million years ago, almost all the Indian

Ocean basin is less than 80 million years old.

The African, Indian, and Antarctic crustal plates converge in the Indian Ocean at the Rodrigues Triple Point. Their junctures are marked by branches of the mid-oceanic ridge forming an inverted Y, with the stem running south from the edge of the continental shelf near Mumbai, India. The eastern, western, and southern basins thus formed are

subdivided into smaller basins by ridges.The ocean's continental shelves are narrow, averaging 200 kilometres (125 mi) in width. An exception is found off Australia's western coast, where the shelf width exceeds 1,000 kilometres (600 mi). The average depth of the ocean is 3,890 m (12,762 ft). Its deepest point is Diamantina Deep inDiamantina Trench, at 8,047 m (26,401 ft) deep; also sometimes considered is Sunda Trench, at a depth of 7,258–7,725 m (23,812–25,344 ft).[10] North of 50° south latitude, 86% of the main basin is covered by pelagic

 sediments, of which more than half is globigerina ooze. The remaining 14% is layered with terrigenous sediments. Glacial outwash dominates the extreme southern latitudes.

The climate north of the equator is affected by a monsoon climate. Strong north-east winds blow from October until April; from May until October south and west winds prevail. In the Arabian Sea the violent Monsoon brings rain to the Indian subcontinent. In the southern

hemisphere the winds are generally milder, but summer storms near Mauritius can be severe. When the monsoon winds change, cyclones sometimes strike the shores of the Arabian Sea and the Bay of Bengal. The Indian Ocean is the warmest ocean in the world.

The Indian Ocean provides major sea routes connecting the Middle East, Africa, and East Asia with Europe and the Americas. It carries a particularly heavy traffic of petroleum and petroleum products from the oil fields of the Persian Gulf and Indonesia. Large reserves of hydrocarbons are being tapped in the offshore areas of Saudi Arabia, Iran, India, and Western Australia. An estimated 40% of the world's offshore oil production comes from the Indian Ocean.[12] Beach sands rich in heavy minerals, and offshore placer deposits are actively exploited by bordering countries, particularly India, Pakistan,South Africa, Indonesia, Sri Lanka, and Thailand.

Due to the relatively high traffic of petroleum tankers, piracy off the Somali coast has been rising. This has been a threat to international shipping since the second phase of the Somali Civil War in the early 21st century.

The warmth of the Indian Ocean keeps phytoplankton production low, except along the northern fringe and in a few scattered spots elsewhere; life in the ocean is thus limited. Fishing is confined to subsistence levels, because its fish are of great and growing importance to the bordering countries for domestic consumption and export. Fishing fleets from Russia, Japan, South Korea, and Taiwan also exploit the Indian Ocean, mainly for shrimp and tuna.

Endangered marine species include the dugong, seals, turtles, and whales.

Plastic pollution threatens the eastern coast of Mozambique Channel

History

The economically important Silk Road (red) and spicetrade routes (blue) were blocked by the Ottoman Empire in ca. 1453 with the fall of the Byzantine Empire. This spurred exploration, and a new sea route around Africa was found, triggering the Age of Discovery.

Culture and literature[edit] The Indian Ocean is known

as Ratnakara in the ancient Sanskrit literature. Ratnakara means "the mine of gems". It's also called Hind Mahasagar in Hindi and other Indian languages.