湛江港潮汐汊道落潮三角洲沉积动力过程

A STUDY ON THE SEDIMENT DYNAMICS OF EBB-TIDAL DELTA OF ZHANJIANG HARBOR TIDAL INLET

湛江港是华南海岸规模最大的中潮溺谷湾型潮汐汊道港湾，口外发育规模巨大、形态典型的落潮三角洲。依据现场调查资料分析，落潮三角洲具有马蹄形浅滩包围中央深槽的地貌结构，由中心至周边为粗砂至极细砂同心半圆带状分布的表层沉积物分布，中央深槽落潮流动力为主，周边浅滩波浪动力和涨潮流动力为主的动力场结构。本文讨论了落潮三角洲沉积动力过程，包括落潮三角洲形成发育的动力条件与泥沙供应条件、落潮三角洲地貌结构、表层沉积物分布和动力场结构之间的一致性，以及落潮三角洲沉积物运移路径。

Zhanjiang Harbor is the largest tidal inlet along South China coasts and the largest ebb-tidal delta developed in the inlet entrance area. This paper analyzed the basic characteristics of the ebb-tidal delta of Zhanjiang Harbor including the morphological structure (semi-circular shoals around central trough), surface sediment distribution (coarse sand to very fine sand with little silt and clay from center to periphery) and hydrodynamical field structure (ebb tidal current dominant in the main ebb-tidal channel, and wave and flood tidal current domimant in the semi-circular shoals). and discussed the sediment dynamics of the hydrodynamical of ebb-tidal delta, the close interrelation among morphology, sedimentology and hydrodynamics, and the sediment transport pattern of the ebb-tidal delta of Zhanjiang Harbor.