三角洲平原上的分流河道通过填积和湖面的频繁波动向湖泊中心方向长距离推进，在浅水三角洲前缘的浅水区发育很有特色的水下分流河道，且在湖面频繁波动过程中，河流、波浪和沿岸流的冲刷作用对沉积物分布起到再改造作用，导致了以水下分流河道砂体为主的三角洲前缘砂体不同程度的席状化。随着气候变得潮湿，湖面相对稳定，季节性、周期性湖面波动的频率、幅度减小，水动力对三角洲前缘砂体的改造和席状化强度减弱。 The distributary channel on the delta plain advances long distances to the center of the lake through filling and the frequent fluctuations of the lake surface. In the shallow waters of the shallow delta front, there are distinctive underwater distributary channels. During the frequent fluctuations of the lake surface, The scouring effect of waves and coastal currents has re-transformed the sediment distribution, leading to different degree of mattification of the delta front sand bodies, which mainly consist of underwater distributary channel sand bodies. As the climate becomes humid, the lake is relatively stable, and the frequency and amplitude of seasonal and periodic lake fluctuations decrease. Hydrodynamic modification and sagging of delta front sand bodies are weakened.