China Sea

Area of the Pacific Ocean bordered by China, Vietnam, Borneo, the Philippines, and Japan. Various groups of small islands and shoals, including the Paracels, 500 km/300 mi east of Vietnam, have been disputed by China and other powers because they lie in oil-rich areas. The chief rivers which flow into the South China Sea are the Red River and Mekong; the main ports include Canton, Hong Kong, Manila, Bangkok, Singapore, and Ho Chi Minh City.

North of Taiwan the sea is known as the East China Sea and to the South as the South China Sea. The latter contains the China Sea Basin, which is over 5,000 m/16,400 ft deep in parts, with an average depth of 4,300 m/14,100 ft. Both these seas contain rich resources of fish, including tuna, mackerel, anchovies, shrimp, and shellfish, which are a major source of food and industry for the countries in the region.

The South China Sea contains the gulfs of Tonkin and Thailand. The latter forms part of the southern area of the sea between Borneo, Malaysia, and Vietnam, lying on the Sunda continental shelf and reaching a depth of only 100 m/328 ft; the Gulf of Thailand is only about 70 m/230 ft deep. Submerged river valleys have been found. Surface currents are driven by the monsoon winds, and tend to be southeastwards in winter and northwestwards in summer.