Aquifer Test Analysis in Fractured Rocks with Linear Flow Pattern

Abstract

ABSTRACT A major vertical fracture in a permeable rock mass may act as an extended well and can provide water through pumping cither directly from the fracture itself or if the fracture width is not enough to install pumps, from an abstraction well drilled in the fracture. In such a case the ground‐water flow is not radial but linear toward the fracture and the flow lines are perpendicular to the fracture axis. A mathematical description of ground‐water flow toward vertical fractures is presented. The cases considered are: (1) an infinitesimally small fracture width corresponding to a planar source or sink, and (2) a finite width fracture in which the effects of ground‐water storage in the fracture are taken into account. The necessary type curves are presented for the main and observation wells. It is observed that the type curve in the linear flow pattern case is extremely different from the radial flow solution especially for long times. In addition, recovery type curves are also given. The application of the method is presented for some available data in the literature.