Experimental Study on the Hydromechanical Behavior of a Gulf of Mexico Reservoir Sand Analogue at in Situ Conditions of Pressure and Temperature Available to Purchase

In order to constrain the contribution of mechanical deformation to injectivity decline in an existing Gulf of Mexico (GoM) field, the hydromechanical behavior of the Castlegate sandstone was studied at close to in situ conditions of pressure and temperature with the goal of devising methods and expectations regarding further work on a waterflooded sandstone formation. In addition to the use of high temperature and pore pressure, the stress conditions for brittle failure were probed using pore pressure buildup as the driving force as opposed to conventional triaxial loading. Through a methodical analysis of the effects of thermal and mechanical loading on flow properties, we observe a very substantial loss of permeability during the attainment of in situ conditions before the initiation of the pore pressure buildup, with the potential of increasing permeability hindrance due to fines migration. Brittle failure during pore pressure buildup is associated with the formation of a thin dilatant shear fracture and moderate permeability reduction. Follow-up work will be aimed at realizing the integration between geomechanical modeling and reservoir core analysis in order to provide a comprehensive understanding of the physical mechanisms involved in waterflooding operations and formulate operational guidelines.