Revealing vertical aquifer heterogeneity and hydraulic anisotropy by pumping partially penetrating wells

Abstract The stratification of sedimentary aquifers introduces spatial variability in hydraulic conductivity, primarily between individual horizontal layers. On larger scales, the vertical heterogeneity enhances anisotropy, with conductivity typically exceeding one. In this study, anisotropy a stratified aquifer is estimated from data tests which water sequentially extracted well sections screened at different depths, and response measured various multilevel observation wells. applicability method demonstrated by field fluvial gravel Upper Rhine Valley, Germany. A homogeneous anisotropic model, models three five layers, are fitted to drawdowns steady-shape regime, differences head locations do not change over time even though values themselves change. position layers based on lithology drilling profile pumping-well location. three-layer model achieved merging insensitive or similar sensitive fits result estimates radial conductivities for all respective models, upscaled effective parameters entire depth case multilayer models. shows significantly higher errors than those heterogeneous locally only reveal but also lead three-times ratio upon upscaling.