中文摘要：

沙岬（沙嘴）是一种海岸动力地貌类型。通过区域地貌背景、海底地貌-浅地层、海洋动力条件、相关的海岸沙坝和现代海滩的分析,认为灯楼角沙岬是来自琼州海峡的东向波浪和来自北部湾的西向波浪两种相向波浪动力平衡、灯楼角东沿岸存在逆时针环流和灯楼角西沿岸存在顺时针环流两者于此辐合,并把带来的砂子沉积下来的结果。

英文摘要：

Sand spit is a kind of dynamic coastal geomorphology. In this paper, the background of the regional landforms, the bottom landform and subbottom profile, the oceanic dynamic situation, the associated coastal sand banks （bars） and the modern beaches are studied. It is thought that the material of the Dengloujiao Cape come from the sand of coastal erosion to its both banks, the scouring from tidal inlet and the sand lifted by wave in the head of the Baoxi Bay, and they are transported to both sides of the cape by littoral currents. The sand spit at the Dengloujiao Cape is formed from 2 reasons, one is the dynamic balance of both waves vis-a-vis, namely the eastward wave from the Qiongzhou Straits and the westward wave from the Beibu Bay ; the other is a convergence of both circulation currents at both sides of the Dengloujiao Cape, namely a counter-clockwise circulation on its east coast and a clockwise one on its west, to make the sand carried by both currents deposit at the cape. The sand spit has emerged for several ten years at least, and it has been spreading. In the future, its development will stop owing to the obstruction of the underwater basalt threshold 1100m away from the shoreline, and most of the sand crossing the threshold will be carried off by strong tidal currents in the central trough with precipitous slope of the Qiongzhou Straits.