Seismic reflection data were used to investigate the multiple stages of headward erosion, incision, and sedimentation on the initiation and evolution of the Central Canyon, a Late Miocene-Pliocene continental slope-parallel canyon on the northwestern margin of the South China Sea. Secondary channels of the early stage generally display deep, V-shaped cross-sectional morphologies, indicating that vertical erosion was dominant in the early stage of canyon formation, while later-phase secondary channels have shallow, U-shaped cross sections, indicating that sedimentation dominated in the late stage. Influenced by gradual sea-level rise, headward erosion shifted the Central Canyon head from the Qiongdongnan Basin to the southeastern margin of the Yinggehai Basin. The length of headward erosion is up to 140 km, equivalent to one-fourth of the total length of the Central Canyon (525 km). The thalweg depth, height, and width of the Central Canyon increases down canyon from 2723 m, 164 m, and 2 km to 5318 m, 1023 m, and 16 km, respectively. This increase is gradual on gently-sloping palaeoseafloor, and more abrupt on steep-gradient palaeoseafloor. Canyon segments on gently-sloping palaeoseafloor are also characterised by a good correlation between canyon height and width. The sediments fill in the Central Canyon differ across the canyon’s segments. Turbidites and debrites infill the upstream segment of the Central Canyon. Turbidites and Mass-transport deposits are widespread in the middle reaches of the Central Canyon. The typical feature of the Central Canyon’s downstream segment is under-compensation, and canyon wall collapse are common in the upper fill of the downstream segment. We reconstruct the multistage evolution of the Central Canyon as comprising primary erosion, burial, renewed erosion, infilling, and abandonment stages. This multistage evolution was mainly controlled by relative sea-level fluctuations of the Qiongdongnan Basin.

利用地震反射数据，研究了南海西北缘晚中新世-上新世大陆坡平行峡谷中央峡谷的起始和演化过程中的前向侵蚀、切割和沉积的多个阶段。早期次生河道一般呈深V形断面形态，说明峡谷形成初期以垂直侵蚀为主，后期次生河道断面呈浅U形，说明沉积作用后期占主导地位。受海平面逐渐上升的影响，上游侵蚀使中央峡谷水头从琼东南盆地向莺歌海盆地东南缘移动。逆流侵蚀长度可达140公里，相当于中央峡谷总长度（525 公里）的四分之一。Central Canyon 的 thalweg 深度、高度和宽度沿峡谷向下分别从 2723 m、164 m 和 2 km 增加到 5318 m、1023 m 和 16 km。这种增加在平缓倾斜的古海底逐渐增加，而在陡峭梯度的古海底上则更为突然。缓坡古海底上的峡谷段的特征还在于峡谷高度和宽度之间的良好相关性。填充在中央峡谷的沉积物在峡谷的各个部分是不同的。浊积岩和碎屑岩填满了中央峡谷的上游部分。浊积岩和质量输送沉积物广泛分布于中央峡谷的中游。中央峡谷下游段的典型特征是补偿不足，下游段上层填土常见峡谷壁塌陷。我们将中央峡谷的多阶段演化重建为包括原始侵蚀、埋藏、更新侵蚀、充填和废弃阶段。这种多阶段演化主要受琼东南盆地海平面相对波动控制。