South China Sea Continental Slope
Being the natural extension of the continental shelf, South China Sea’s continental shelf lies on the peripheral part of the continental shelf, covering a rough area of 1.2 million kilometers which represents 49% of the total, it is the most broadly distributed topographical unit in the South China Sea area. The water depth is between 150 meters to 3,600 meters. There exists a terminal depth of 3,200~3,500 meters in the north east part and north part of the basin, while the other parts sees a terminal depth of 3,800~4,000 meters. Trapezoidally descending is one of the main characteristics of this area. According to the study, five sections of steps arising from South China Sea continental shelf as follows:
300--400-meter steps, such as Dongsha Step and Zhongshashangtai Step;
1000--1500-meter steps, such as Xisha Step located outside of Pearl River mouth and in Xisha Islands;
1500--2000-meter steps, such as Nansha Step mainly located on the southern slope;
2200--2400-meter steps, developed from the western slope and Zhongshaxia Step;
2500--2800-meter steps, distributed on the deep-sea water steps at the rim of the slope.