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Marine Places

South China Sea

The South China Sea is the largest body of water after the five oceans, and its productive waters account for more than eight percent of the world’s fish catch. This tropical sea is fed with water from the Java Sea through the Sunda Strait, which flows weakly north, and out through the Taiwan Strait. The northern part of the area can be battered by typhoons in the late summer.

The deep central basin of the South China Sea is surrounded for the most part by broad continental shelves. There are oil and natural gas fields in the Gulf of Tongking and the Vereker Banks in the north, and off Borneo and across the Sunda Shelf in the south. The South China Sea is the second busiest sea lane in the world, with at least 25 percent of the world’s crude oil passing through its waters. The South China Basin is punctuated by banks and reefs, which contain more than 200 tiny islands. Among these are the uninhabited Spratly Islands, whose ownership is disputed between China, Vietnam, Taiwan, Malaysia, Brunei, and the Philippines. The claims of the various countries are motivated by the presence of minerals, and it is estimated that vast oil reserves lie underneath the islands. The most southern part of the sea is underlain by the shallow Sunda Shelf, a land bridge that connected Borneo, Sumatra, and Java to the Asian mainland during the last ice age.

South China Seazoom image
  • Area 1.4 million square miles (3.7 million square km)
  • Maximum Depth 16,457 ft (5,016 m)
  • Inflows Xi Jiang, Red, Tha Chin, Mekong rivers