High Quality Content by WIKIPEDIA articles The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around 3,500,000 square kilometres (1,400,000 sq mi). The area's importance largely results from one-third of the world's shipping transiting through its waters, and that it is believed to hold huge oil and gas reserves beneath its seabed.