Water table response to a tidal agitation in a coastal aquifer: The Meyer-Polubarinova-Kochina theory revisited

The linear potential model of Meyer and Polubarinova-Kochina (MPK) solves Laplace's equation in a quadrant, the vertical face of which is subject to a harmonic variation of hydraulic head induced by a tide. On the horizontal face of the quadrant a linear combination of the partial derivatives of the head with respect to time and with respect to the vertical Cartesian coordinate are linearly related. The fields of pore pressure (head) and Darcian velocity, trajectories of marked particles, the oscillating phreatic surface and its upper envelope are obtained. Hydrograph in a piezometer located 60. m from the shore line in a thick unconfined coastal aquifer (Oman) is interpreted by the analytical results of the model using the detected groundwater amplitude attenuated as compared with the tide amplitude. MPK method provides a potentially superior description to the Dupuit-Forchheimer method for tidally driven phreatic systems.