Estimation of the hydraulic properties of a fractured aquifer using numerical experiments with the discrete fracture network model

Inversion simulations have been applied to reconstruct the spatial variability of the hydraulic characteristics of fractured aquifers. Discrete fracture network (DFN) models exhibit good performances for complex fractured systems, whereas few hydraulic tomography (HT)-based inversion studies of DFN models provide new insights into data selection. The study objective is to find reasonable data selection strategies that accurately estimate the hydraulic properties in a DFN model. A two-dimensional DFN model was constructed, and nine pumping tests were designed for forward simulations. Three cases were designed considering different conditions during inversion simulations. Two hypotheses were verified. First, the feasibility of using HT to identify the hydraulic properties in DFN models with high heterogeneity was demonstrated. Second, the flow behaves as quasi-steady flow because of the minimal effects of storage, and the inverse model can use steady-state conditions to estimate hydraulic conductivity. This study promotes the use of HT surveys for mapping fracture zones.