Technological advances in multiple-stage hydraulic fracturing and horizontal drilling have improved the overall profitability of oil-shale plays by enhancing matrix/wellbore connectivity. However, as the reservoir matures, primary-production mechanisms no longer drive oil to the hydraulic fractures, making the improvement of matrix/wellbore connectivity insufficient to provide economically attractive production rates. This study presents experimental results on the use of carbon dioxide (CO2) as an enhanced-oil-recovery (EOR) agent in preserved, rotary sidewall reservoir core samples with negligible permeability