This occurs because, in its natural equilibrium state, the hydraulic pressure of groundwater in the pore spaces of the aquifer and the aquitard supports some of the weight of the overlying sediments.
12.
These aquifers are called the "'Upper and Lower Colima "'and are separated by a layer that acts as a semi-permeable aquitard, which allows the descending and ascending vertical transfer of water.
13.
Semiconfined aquifers with a slowly permeable layer overlying the aquifer ( the aquitard ) can be included in the model by simulating vertical flow through it under influence of an overpressure in the aquifer proper relative to the level of the watertable inside or above the aquitard.
14.
Semiconfined aquifers with a slowly permeable layer overlying the aquifer ( the aquitard ) can be included in the model by simulating vertical flow through it under influence of an overpressure in the aquifer proper relative to the level of the watertable inside or above the aquitard.
