Some Practical Approaches to World Petroleum Resource Assessment
Uncertainty in petroleum resource estimation can be mitigated by using different approaches in making resource estimates for a given area. We divide methods and data into two broad categories. The first is based on geologic data, which aim at estimating the resources of a basin by gaining an understanding of the processes of petroleum formation, migration, and trapping. The second is based on statistical methods, which estimate the resources of a basin by extrapolating the industry’s past experience in drilling and discovery to forecast future discoveries. Results of these approaches are compared for Nigeria, North Africa, and many of the world’s offshore areas. Undiscovered offshore petroleum resources outside the United States, Canada, and communist countries were estimated by both methods to be ~ 130 billion bbl. For Nigeria the two methods agree at about 4-6 billion bbl of undiscovered oil. In contrast, for North Africa, where the geologic estimate of undiscovered petroleum is 16 billion bbl and the statistical estimate is 5 billion bbl, the two methods are not in close agreement.