Isothermal Permeability of the Argillaceous Cobourg Limestone

The paper presents the results of an experimental evaluation of the permeability of the heterogeneous argillaceous limestone from the Cobourg formation located in southern Ontario, Canada. The low permeability of the limestone necessitated the development of experimental techniques for effectively measuring the permeability of the rock. In particular, we examine the results of pressurization of a fluid-filled co-axial cylindrical cavity of finite length cored into a 150 mm diameter cylinder of the Cobourg Limestone. The orientation of the cavity is either normal to or along the nominal stratifications identified by the argillaceous partings separating the quartzitic phases. Both steady state and transient tests are used to estimate the permeability of the Cobourg Limestone. The paper also investigates the influence of a nominal axial load on the permeability of the rock.