THE STABILITY ANALYSIS OF XIYANG TIDAL CHANNEL IN RADIAL SUBMARINE SAND RIDGES ALONG NORTH JIANGSU
苏北岸外辐射沙洲王港西洋潮流通道稳定性研究

The study on the stability is a first problem in costruction of harbour on the tidal channel in the mud silt coast. In this paper, environmental background of Xiyang tidal channel is firstly analysed, then based on the data from the practical investigation, the stability of Xiyang tidal channel is comprehensively studied using manifold analysis methods including: GIS, remote sensing, sediments (grain size, mineral and foraminifera), marine hydrodynamic conditions and so on. Based on the above works, the conclusions drawn are as follows: 1. Xiyang tidal channel, located between Wanggang coast tending gradually to stable and radial submarine sand ridges under a dynamic equilibrium state, has an environmental background beneficial to its stability. After the loss of a great deal of sediments directly from the Huanghe River in 1855, Xiyang channel began extending, widening and deepening southwards. 2. The tide in Xiyang channel is strong, with a maximum tidal velocity of more than 2 50 m/s. Ebb current velocity is generally larger than flood current velocity. The net transport of sediment by tidal current is mainly towards the outside of Xiyang channel. The hydrodynamic conditions in Xiyang channel are favorable to maintaining water depth of the channel. 3. Overall, Xiyang tidal channel is under the stable condition, but the stability of different parts in Xiyang channel is a little bit different. The south mouth of the east channel is the least stable in Xiyang channel, but the west channel, especially its south deep trough, is more stable.