Flow and transport in heterogeneous porous formations subject to uncertainty in statistical description of the hydraulic log-conductivity spatial behaviour

The effect of a periodic spatial behaviour of the mean log-conductivity (logK) in random heterogeneous aquifers was investigated by numerical simulations. The adopted schematization reflects the spatial inhomogeneity due to an inexact definition of spatial statistical properties of media and can be considered a rough description of the hierarchical sedimentary architecture of porous formations. The solution of investigated cases was achieved by use of both the stochastic finite element method (SFEM) and the Monte Carlo simulations (MC). From the results it was possible to distinguish the contribute of the fluctuating mean log-conductivity field in the plume evolution. Comparison between SFEM and MC outcome reveals strong nonlinearity effects related to the spatial variability of the mean of the logK field also when its variance is negligible