Pumping test analysis using a layered cylindrical grid numerical model in a complex, heterogeneous chalk aquifer

Impact of model complexity and multi-scale data integration on the estimation of hydrogeological parameters in a dual-porosity aquifer

“…Addressing limitations inherent analytical solutions to improve the match between observed and simulated time-drawdown curves requires the implementation of numerical models (e.g. Mansour et al, 2011;Raghavan, 2004;Schad and Teutsch, 1994;Thorbjarnarson et al, 1998). Pumping tests have been simulated with finite difference (Barrash and Dougherty, 1997;Cheng and Chen, 2007;Halford and Yobbi, 2006;Kaleris et al, 1995;Lee et al, 2007;Leven and Dietrich, 2006;Mohamed and Rushton, 2006;Raghavan, 2009Raghavan, , 2006Schroth and Narasimhan, 1997), finite elements, and hybrid finite elements -finite difference models (Chen and Jiao, 1999;Lebbe et al, 1992).…”

Automatic estimation of aquifer parameters using long-term water supply pumping and injection records

“…The Theis (1935) solution is the first analytical model developed for transient analysis of a pumping test in a confined aquifer, but numerous type curve solutions have since been developed over the next few decades for different aquifer types and boundary conditions (e.g., Hantush and Jacob 1955;Neuman 1974;Moench 1997;Mathias and Butler 2006;Mishra and Neuman 2011). The application of these analytical models is sometimes restricted in complex hydrogeological conditions, where some features that significantly affect groundwater flows are not considered (e.g., Mansour et al 2011). Although the use of analytical models may lead to good matches between observed drawdowns and type curves, the estimated hydraulic properties may be scenario-dependent-for example, Wu et al (2005) demonstrated that the conventional analysis of aquifer tests yields biased T estimates that evolved with time and depended on the location of monitoring boreholes, and the Electronic supplementary material The online version of this article (doi:10.1007/s10040-016-1407-x) contains supplementary material, which is available to authorized users.…”

Grid Refinement in Cartesian Coordinates for Groundwater Flow Models Using the Divergence Theorem and Taylor's Series

“…In radial flow modeling, for example, Rushton and Redshaw (1979) or Mansour et al (2011), the use of a logarithmic radial mesh increases the node density in the region around the well where steep hydraulic gradients occur and reduces the node density in the more distant parts of the aquifer. The accuracy of the solution, on the other hand, depends on many factors.…”

“…A smooth change in the hydraulic gradient, as is the case in regional aquifers, for example, allows the use of a large interval without affecting the accuracy of the solution. In radial flow modeling, for example, Rushton and Redshaw (1979) or Mansour et al (2011), the use of a logarithmic radial mesh increases the node density in the region around the well where steep hydraulic gradients occur and reduces the node density in the more distant parts of the aquifer. However, steep hydraulic gradients may occur in a regional aquifer because of the existence of special features, such as rivers, wells, faults, and changes in the aquifer properties.…”