A new perturbation solution of groundwater table fluctuations in tidal beaches

This paper modeled tide-induced groundwater flow in a vertical beach with a thin submarine outlet-capping. By implementing a perturbation method based on the Boussinesq's equation, a new approximate solution was derived for the model. Then the solution was compared with previous analytical solutions derived from the linearized Boussinesq's equation. The results showed that the error between the present and previous solutions increases with the value of the ratio of tidal amplitude to the aquifer's depth below the mean sea level and the leakage of the submarine outlet-capping.