Transmissivity Estimates by Specific Capacity Data of Some Fractured Italian Carbonate Aquifers

Abstract

Transmissivity estimates can be obtained by different approaches, mainly analytical and empirical. The application of analytical methods requires checking non-linear well losses due to turbulence and vertical flow related to partial penetration. The empirical approach relates transmissivity values to specific capacity data measured in the same well. The interpretation of available pumping tests highlights porous media solutions’ applicability in most of the step-drawdown curves analyzed. Double or triple porosity approaches are more appropriate only for wells located close to fault systems. In this work, a new relationship to estimate transmissivity by specific capacity data in some Italian carbonate aquifers is proposed. The comparison with other relationships available in the literature for similar aquifers worldwide confirms the validity of a general equation for carbonate aquifers, helping the spatial characterization of aquifer transmissivity in scarce data regions. Nonetheless, the use of equations of the same kind with different coefficients allows good results on our set of data. Results can improve the knowledge of fractured–karst aquifers by also including data from Central Italy.

Keywords

• groundwater
• pumping test
• transmissivity
• specific capacity
• fractured carbonate aquifers