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建立了冲积地层的三维模型，在模拟过程中，认为冲积地层中粗粒河道带沉积的空间分布、比例、连通性是河道带宽度、泛平原宽度、满岸河深、河道带与溢岸沉积速率、决口位置与周期、压实作用和构造运动（倾斜和断裂）的函数。模型认为泛平原表面宽度和长度变化是由单一河道带造成的，泛平原地形变化是由河道带时空变化、泛平原沉积速率、压实作用、局部或区域构造运动控制的，决口的位置和时间是受洪水的频率、幅度及与河道带坡度相关的泛平原坡度局部变化而决定的，河流改道一般出现在泛平原坡度最大的地方。模型预测表明河道带沉积比例、砂体连通性和空间分布是随距决口点的距离和剖面方位变化的函数，在决口点以上的河流，由于在固定河道带内加积，砂体宽厚比低。由决口点向下，河道带趋于相互联结，导致砂体宽厚比高。沿河谷向下加积速率增加，可导致河道带沉积比例和连通性增加，沿河谷向下加积速率降低可导致河道带在泛平原上游地区频繁决口。构造倾斜和断层可增加局部决口概率使河道带一般转向最大沉降区。
A three-dimensional model of alluvial strata was established. During the simulation, it is considered that the spatial distribution, proportion and connectivity of the sediments in the alluvial strata are the width of the river channel, the width of the pan-plains, the depth of the river bank, Velocity, bursts position and period, compaction and tectonic movement (tilt and fracture). The model considers that the change of surface width and length of the pan-plains is caused by a single river channel. The change of pan-plains topography is controlled by temporal and spatial variations of the river channel, the depositional rate of the pan-plains, compaction, local or regional tectonic movement, Is determined by the frequency and amplitude of floods and the local changes of the gradient of the pan-plains associated with the slope of the river channel. The diversion of the river generally occurs at the place where the gradient of the pan-plains is greatest. The model prediction shows that the ratio of sedimentation, sand body connectivity and spatial distribution of the river channel are a function of the distance from the breach point and the change of the azimuth of the section. In the rivers above the breaching point, . By the burst point down, the river tends to be linked to each other, resulting in high ratio of sand width. The increase of downwelling rate along the river valley can lead to the increase of sedimentary proportion and connectivity in the river channel, and the decrease of the downwelling rate along the river valley can lead to the frequent breaking of the river channel in the upstream of the pan-plains. Tectonic tilt and fault can increase the probability of local breaching so that the riverway belt is generally diverted to the maximum settlement.