A model of profile evolution on wave-dominated mud coast

This paper developed a theory model to simulate the evolution of nearshore profile on wave-dominated mud coast of the abandoned Huanghe Delta, which has been undergoing erosion since the shift of the Huanghe River in 1855. The model is established according to the computation of wave-induced shear stresses on mud profile, and the calculation of mud erosion rate. The sea level fluctuation caused by tide is introduced into the model. A new idea of the effective scouring waves, derived from local wave climate, is proposed in this paper to numerically incorporate the influences of the geological processes occurring during coast erosion. The eroded nearshore profiles exhibit monotonous concave upward. The maximum curvature of profile lies below the mean low tidal level. As the erosion continues,the maximum curvature moves down and shoreward. The position of the maximum curvature of nearshore mud profile can be used as a measure to estimate the evolution states of the mud coast on the abandoned Huanghe Delta. In Lianyungang, the mud profile approaches a steady state when the maximum curvature reaches down to the water depth of about 6 m below the mean sea level.