Abstract: According to available formation and field survey it is confirmed that largescale land subsidence occurred along the present Puqian port during the Qiongzhou earthquake of 1605,leading to changing the Sanjiangshui River course-generation of the tributary (the Dongzhai River).After the earthquake in point,large-scale land subsidence was continuing in a low speed and eventually the present Dongzhai Port that streches into the inland for the largest distance has so far been formed.

摘要： 本文通过历史资料考证和野外调查证实:1605年琼州大地震时在铺前港一带海边发生大片陆地沉陷,造成三江水变迁,东寨河成为三江水之一,大震后至今380年来沿东寨河地区继续发生大幅度缓慢下沉,终于使东寨河演变成今天海南岛伸入内陆最长的港湾——东寨港。