Barker Solution for Constant-Head Tests in Confined and Fractured Aquifers

Well-aquifer configuration for Barker (1988) constant-head test

A mathematical solution by Barker (1988) is useful for determining the hydraulic properties (hydraulic conductivity and specific storage of the aquifer or fractures; hydraulic conductivity and specific storage of matrix; and flow dimension) of confined (single porosity) and fractured (double porosity) aquifers. Analysis involves matching the Barker solution to discharge data collected during a constant-head (constant-drawdown) test. The so-called generalized radial flow model simulates unsteady, n-dimensional flow to a fully penetrating source in an isotropic, single-porosity confined aquifer or a double-porosity fractured aquifer. includes options for slab and spherical matrix blocks in the double-porosity case.

AQTESOLV provides visual and automatic methods for matching the generalized radial flow model to constant-head test data. This easy-to-use and intuitive software promotes rapid and accurate determination of aquifer properties.

Assumptions

The following assumptions apply to the use of the Barker generalized radial flow model:

  • aquifer has infinite areal extent
  • aquifer is homogeneous, isotropic and of uniform thickness
  • potentiometric surface is initially horizontal
  • aquifer is confined
  • flow is unsteady
  • wells are fully penetrating
  • water is released instantaneously from storage with decline of hydraulic head

Solution
Options

provides the following options for the Barker generalized radial flow model:

  • recovery

References

Barker, J.A., 1988. A generalized radial flow model for hydraulic tests in fractured rock, Water Resources Research, vol. 24, no. 10, pp. 1796-1804.

Moench, A.F., 1984. Double-porosity models for a fissured groundwater reservoir with fracture skin, Water Resources Research, vol. 20, no. 7, pp. 831-846.