Characterization of the aquifer’s hydraulic properties using different pumping test modes: From oscillatory hydraulic tomography to steady state hydraulic tomography

Abstract

The characterization of aquifers hydraulic properties (e.g., transmissivity and storativity) and understanding its hydrodynamics are very important for groundwater management. Hydraulic tomography (HT) is one widely used tool to achieve it. In this paper, we use the principal components geostatistical approach (PCGA) to map the transmissivity and the storativity of an aquifer by using oscillatory pumping tests, pumping tests (transient) and steady state data. Firstly, through a synthetic case study, we investigate the differences between HT results using different observation data obtained from different hydraulic tests. Moreover, we explore how sensitive are T and S estimates obtained using different observation data to changes in the hydraulic properties of a buffer area surrounding the inversion domain. Then, the synthetic case study is repeated using a real field configuration and a field application is performed. Results show that the heterogeneous area surrounding the inversion domain have a significant effect on Hydraulic Tomography results. Results also show that high frequency oscillatory pumping tests provide the best hydraulic tomography results especially for the storativity fields. Such effect becomes more pronounced when using transient and steady state observations of constant flow-rate pumping tests. Surrounding heterogeneity has a considerable effect on T field which in return affects the solution of S field as well.