An Experimental Study for Mechanical Formation Damage

Abstract

Summary This work presents triaxial experiments that were carried out in different stress paths, with measurements of P- and S-wave acoustic velocity and permeability, to evaluate mechanical formation damage. In some reservoirs, large deformations occur during oil production because of the effective stress increase. This may cause permanent damage to the reservoir as the rock structure changes, lowering the permeability and the final oil recovery. The experiments showed that plastic behavior is always present and that a "cap" model may represent the yield region. This methodology allowed a near-wellbore evaluation and permeability investigations using a stress-path concept.