Fifty-five carbonate and sandstone reservoirs in North Dakota are possible candidates for CO2 flooding with recoverable reserves of 181 Mmbo at an 8% recovery factor of the original oil in place. An additional 25 fields have possible CO2 flooding enhanced oil recovery of 106 Mmbo. North Dakota reservoir characteristics are similar to successful CO2 flood projects in West Texas and the Canadian Williston Basin. However, North Dakota reservoirs tend to be deeper and on larger well spacing than successful West Texas CO2 floods. Constraints limiting North Dakota CO2 development are reservoir depth, large well spacing, and presence of vertical fractures across reservoir boundaries, heterogeneous reservoirs, and strong natural water influx or high water cuts in mature waterflood projects.

Many of the reservoirs listed in this report with Probable and Possible CO2 flood reserves may not be economic to develop due to high development costs for installation of CO2 supply pipelines, current oil prices and/or CO2 purchase costs. The intent of the study was to quickly identify and qualify those reservoirs with CO2 potential. Additional detailed research, geological and engineering studies would be required, beyond the scope of this report, to assess the effectiveness, economic feasibility and the ultimate potential of each individual field presented in the analysis based upon the unique characteristics present in each reservoir.