Daviau et al. Solution for Horizontal Wells in Confined Aquifers

Description

A mathematical solution for horizontal wells by Daviau et al. (1985) is useful for determining the hydraulic properties (transmissivity, storativity and hydraulic conductivity anisotropy ratio) of nonleaky confined aquifers. Analysis involves matching the Daviau et al. solution to drawdown data collected during a pumping test in a horizontal well.

AQTESOLV provides visual and automatic methods for matching the Daviau et al. solution to pumping test data from a horizontal well. 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 Daviau et al. horizontal well solution:

• aquifer has infinite areal extent
• aquifer is homogeneous, isotropic and of uniform thickness
• potentiometric surface is initially horizontal
• aquifer is nonleaky confined
• flow is unsteady
• water is released instantaneously from storage with decline of hydraulic head
• diameter of the horizontal well is very small so that storage in the well can be neglected

Solution Options

AQTESOLV provides the following options for the Daviau et al. method for a horizontal well:

• constant or variable pumping rate with recovery
• multiple horizontal wells
• multiple observation wells
• partially penetrating observation wells

Benchmark

Comparison of AQTESOLV (blue line) and published horizontal well function values (symbols) for Ld=0.125 (Clonts and Ramey 1986).

References

Daviau, F., Mouronval, G., Bourdarot, G. and P. Curutchet, 1985. Pressure analysis for horizontal wells, SPE Paper 14251, presented at the 60^th Annual Technical Conference and Exhibition in Las Vegas, NV, Sept. 22-25, 1985.

See also: solution methods, pumping tests