长江口拦门沙及水下三角洲的动力沉积和演变

SEDIMENT DYNAMICS AND EVOLUTION OF THE MOUTHBAR AND SUBAQUEOUS DELTA IN THE YANGTZE ESTUARY

分析了长江河口拦门沙和水下三角洲及河口和邻近水域的水系和水团的特征，论述了河口混浊带羽状锋系的分布移动规律，并对河口拦门沙的物理、化学、生物及地质屏障效应作了评估。通过对泥沙分布、沉积率和沉积程序的研究，探明了河口拦门沙及水下三角洲的泥沙交换和演变。根据以上所述，探讨了长江河口深水航道的选址问题，为有关管理部门提供了科学的数据。

This paper examines the characteristics of the mouthbar and subaqueous delta,and the water masses and water systems in the Yangtze Estuary and nearby coastal waters. The hydrodynamics of estuarine plume,and the fronts and turbidity systems are described with reference to their dis- tribution and movement.Physical,chemical,biological and geological barrier effects of the estu- arine mouthbare are evaluated.Through examining sediment distribution,sedimentation rate and depositional sequence,the sediment exchanges and evolution of the estrarine mouthbar and sub- aqueous delta are described.Based on the information above,the site selection for the deep navi- gational channel in the Yangtze Estuary is discussed.These data should provide a scientific basis for the management of the Yangtze Estuary.