The formation of river mouth deltas accompanied by channel networks and the preservation mechanism of tidal flats

我们在实验水槽中再现了潮汐流形成的潮汐通道，并进行了统计和分形分析来量化实验中观察到的几何特征。分析发现，潮汐变化的格局对潮道形态有重要影响。对考虑渗流的潮道形成过程进行了数值模拟。研究发现，渗流对潮道分岔有较强的影响，渗流使潮道规模增大。小规模的潮汐通道类似于河流中形成的多个沙洲，如在受降雨影响的陡坡上形成的通道和由波浪形成的菱形小沟。大尺度潮道是由潮汐波动引起的地下渗流形成的片状流形成的。

We reproduced tidal channels formed by tidal flow in an experimental flume, and performed statistic and fractal analyses to quantify geometrical features observed in the experiments. It is found from the analyses that the pattern of tidal fluctuation has a significant impact on the configuration of tidal channels. We performed numerical simulation of the formation of tidal channels with seepage flow considered. It is found that seepage flow has a strong influence on channel bifurcation, and that seepage flow increases the scale of tidal channels. It is suggested that small scale tidal channels are analogous to multiple bars formed in rivers, as channels formed on steep slopes subject to rainfall and rhomboid rills formed by waves. The large scale tidal channels are formed by sheet flow created by seepage flow coming from underground due to tidal fluctuations.