Type curves for radial flow in heterogeneous aquifers

Radial flow towards wells in variable hydraulic conductivity aquifers is examined: the law of variation of conductivity adopted, typical for fissured rocks, is exponential with depth. Analytical solution for drawdown is achieved through the Boltzmann transformation: results are presented as dimensionless type curves. In particular, for high temporal values, the resulting well function is linear on semilogarithmic paper, as in the Jacob method for a homogeneous aquifer. However, it is showed that the homogeneous hypothesis may lead to erroneous estimation of aquifer characteristics. -from English summary