DISCRETE STABILITY OF THE DIFFERENTIAL SYSTEM METHOD EVALUATED WITH GEOSTATISTICAL TECHNIQUES

The Differential System Method (DSM) permits identification of the phy sical parameters of finite-difference groundwater flow models in a con fined aquifer when piezometric head and source terms are known at each point of the finite-difference lattice for at least two independent f low situations for which the hydraulic gradients are not parallel. Sin ce piezometric head data are usually few and sparse, interpolation of the measured data onto a regular grid can be performed with geostatist ical techniques. We apply kriging to the sparse data of a synthetic aq uifer to evaluate the stability of the DSM with respect to uncorrelate d measurement errors and interpolation errors. The numerical results s how that the DSM is stable.