Experimental Investigation of Clay Effects in Reservoir Rock on Permeability Reduction in Water Injection Process to Hydrocarbon Reservoirs

Easiness in water injection process into oil reservoir is one of the important factors in water injection projects. The presence of clay in reservoir rock may cause undesire effects. Because of different structures, clays have different quality degree on reservoir rocks permeability. Clays can be aggregated in pores and throats by injected water or exist in rock structure. Clay swelling with consideration of types and structures may lead to permeability reduction. In this research, three core samples have been selected from an oil field in south of Iran to investigate clay effects and its mechanism during water injecting in to the surrounded aquifer. Firstly, type and amount of clay was estimated by XRD tests. Then permeability reduction was the measured in core flooding experiments by distillated water injection to create maximum clay swelling in case clay swelling is effective in permeability reduction.