Evolution of Pore Structure and Permeability of Rocks in Laboratory Experiments

Rock strength is profoundly affected by pore fluids through diverse mechanical and chemical interactions (Walder and Nur, 1984; Carter et al., 1990). Conversely, deformation can easily result in large changes of the pore structure (Paterson, 1978; Wong, 1990). Because transport properties of rocks, including permeability and electrical resistivity, are directly determined by the pore structure (Walsh, 1965; Simmons and Richter, 1976; Gangi, 1979; Shankland et al., 1981; Heard and Page, 1982), those properties can also be substantially altered by deformation. As a direct consequence of the relationships among the physical state of pore fluids, fluid transport, and mechanical deformation, rocks may exhibit complex, time-dependent mechanical and transport properties.