Gringarten and Ramey Solution for Fractured Aquifers with a Single Horizontal Plane Fracture
A mathematical solution by Gringarten and Ramey (1974) is useful for determining the hydraulic properties (hydraulic conductivity, specific storage, hydraulic conductivity anisotropy and fracture radius) of fractured aquifers with a single horizontal plane fracture intersecting the control well. Analysis involves matching the solution to drawdown data collected during a pumping test. The solution estimates hydraulic conductivity anisotropy in a vertical (x-z) plane.
AQTESOLV provides visual and automatic methods for matching the Gringarten and Ramey solution to pumping test data. This easy-to-use and intuitive software promotes rapid and accurate determination of aquifer properties.
The following assumptions apply to the use of the Gringarten and Ramey horizontal fracture solution:
- aquifer has infinite areal extent
- aquifer has uniform thickness
- aquifer potentiometric surface is initially horizontal
- fractured aquifer represented by anisotropic nonleaky confined system with a single plane horizontal fracture
- flow is unsteady
- water is released instantaneously from storage with decline of hydraulic head
- diameter of control well is very small so that storage in the well can be neglected
AQTESOLV provides the following options for the Gringarten and Ramey horizontal fracture solution:
- variable pumping rates
- multiple pumping wells
- multiple observation wells
Gringarten, A.C. and H.J. Ramey, 1974. Unsteady state pressure distributions created by a well with a single horizontal fracture, partial penetration or restricted entry, SPE Journal, pp. 413-426.