RESPONSE TO CONSTANT-FLUX PUMPING IN SLANT CONFINED AQUIFERS

Traditionally, the problems of groundwater flow induced by pumping often assume that the aquifer is homogeneous, isotropic, and horizontal infinite-extent with a uniform thickness and the pumping well vertically penetrates the aquifer. The aquifer system may actually slant as a sloping fault or fractured massif zone, sloping deposition zone, etc. This study focuses on developing a mathematical model for describing the transient drawdown response for a constant-flux pumping in a slant confined aquifer (SCA) system with a partially penetrating well. Semi-analytical solution of this model in Fourier domain is derived by applying finite Fourier sine transforms to x and y and finite Fourier cosine transform to z. The solution of the model for transient drawdown is obtained directly by utilizing the inverse Fourier transform. This new solution can be shown to reduce to the solution for horizontal aquifers. The numerical results indicate that a SCA system with a larger slope angle gives a smaller aquifer drawdown indicating that the slope angle of the SCA system influences the aquifer drawdown distribution. This solution can be used either to predict the spatial and temporal drawdown distributions or to investigate the impacts of the slope angle on drawdown distribution in a SCA system.