Indian Ocean

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Map of Indian Ocean

The Indian Ocean is the ocean surrounded by Asia to the north, Australia and the Pacific Ocean to the east, the Southern Ocean to the south, and Africa and the Atlantic Ocean to the west. It is named for the river Indus and Ancient India on its north shore. The Bay of Bengal, the Arabian Sea, the Persian Gulf and the Red Sea are all parts of this ocean.

The deepest point in the Indian Ocean is in the Java Trench near the Sunda Islands in the east, 7500 m (25,344 feet) deep. The average depth is 3,890 m (12,762 ft). The Indian Ocean is the third largest ocean, 28,350,000 square miles in size. The majority is in the southern hemisphere.


The borders of the Indian Ocean, as delineated by the International Hydrographic Organization in 1953 included the Southern Ocean but not the marginal seas along the northern rim, but in 2000 the IHO delimited the Southern Ocean separately, which removed waters south of 60°S from the Indian Ocean but included the northern marginal seas. Meridionally, the Indian Ocean is delimited from the Atlantic Ocean by the 20° east meridian, running south from Cape Agulhas, and from the Pacific Ocean by the meridian of 146°49'E, running south from the southernmost point of Tasmania. The northernmost extent of the Indian Ocean (including marginal seas) is approximately 30° north in the Persian Gulf.

The Indian Ocean covers 70,560,000 km2 (27,240,000 sq mi), including the Red Sea and the Persian Gulf but excluding the Southern Ocean, or 19.5% of the world's oceans; its volume is 264,000,000 km3 (63,000,000 cu mi) or 19.8% of the world's oceans' volume; it has an average depth of 3,741 m (12,274 ft) and a maximum depth of 7,906 m (25,938 ft). All of the Indian Ocean is in the Eastern Hemisphere and the centre of the Eastern Hemisphere, the 90th meridian east, passes through the Ninety East Ridge.

The Indian Ocean is bounded by Iran, Pakistan, India, and Bangladesh to the north; the Malay Peninsula, the Sunda Islands of Indonesia, and Australia to the east; Antarctica to the south; and Africa and the Arabian Peninsula to the west. In the southwest it joins the Atlantic Ocean south of the southern tip of Africa, and to the east and southeast its waters mingle with those of the Pacific Ocean.

The Indian Ocean has the fewest marginal seas of the major oceans. To the north are the inland Red Sea and Persian Gulf. The Arabian Sea is to the northwest, and the Andaman Sea to the northeast. The large gulfs of Aden and Oman are to the northwest, the Bay of Bengal is to the northeast, and the Great Australian Bight is off the southern coast of Australia.

Major Ports

  1. Aden, (Yemen)
  2. Beira, (Mozambique)
  3. Chennai, (India)
  4. Chittagong, (Bangladesh)
  5. Colombo, (Sri Lanka)
  6. Dar es Salaam, (Tanzania)
  7. Dubai, (UAE)
  8. Durban, (South Africa)
  9. Ennore, (India)
  10. Galle, (Sri Lanka)
  11. Hambantota, (Sri Lanka)
  12. Jakarta, (Indonesia)
  13. Karachi, (Pakistan)
  14. Kochi, formerly Cochin (India)
  15. Kolkata, formerly Calcutta (India)
  16. Medan, (Indonesia)
  17. Mombasa, (Kenya)
  18. Mormugao Port, (India)
  19. Mumbai, formerly Bombay (India)
  20. Muscat, (Oman)
  21. Nagapattinam, (India)
  22. Panambur, (India)
  23. Paradip Port, (India)
  24. Perth, (Australia)
  25. Port Louis, (Mauritius)
  26. Singapore
  27. Tuticorin, (India)
  28. Vizagapatam formally Visakhapatnam, (India)
  29. Yangon, (Burma)
  30. Zanzibar