Tidal fluctuations in a leaky confined aquifer: Dynamic effects of an overlying phreatic aquifer

Tidal fluctuations in a leaky confined coastal aquifer are damped significa ntly due to leakage into an overlying phreatic aquifer. Jiao and Tang [1999 ] presented an analytical solution to a simple model describing this phenom enon. Their solution assumes that the tidal fluctuations in the overlying p hreatic aquifer are negligible (i.e,, a static phreatic aquifer), Here we e xamine dynamic effects of the overlying aquifer based on a new approximate analytical solution. The numerical results indicate that the dynamic effect s can be significant for a relatively large leakage and a high transmissivi ty of the phreatic aquifer.