Fluid leakage through fractures in an impervious caprock embedded between two geologic aquifers

The paper develops an analytical result for the flow through a single fracture under a hydraulic gradient between the two aquifer regions and takes into account permeability characteristics of all components of the system. Non-dimensional results are presented to illustrate the influence of the permeability mis-match between the two geologic formations and the permeability and geometry of the fracture on the flow rate through the fracture. The analytical result is then used to develop additional results for leakage through a swarm of vertically aligned hydraulically non-interacting fractures and a damaged region containing a densely spaced array of vertically aligned fractures and worm hole type features in the caprock. The work presents a convenient result for the estimation of leakage from storage formations in geoenvironmental applications.

► We examines steady leakage from fractures between aquifers.
► We consider the permeability characteristics of all components in the system.
► A convenient analytical result is provided.
► Steady leakage from a variety of defects can be estimated.