Prospective resources are those deposits that are estimated, on a given date, to be potentially recoverable form undiscovered accumulations. Frequently, this may be in areas where geoscience and engineering data are unable to clearly define the area.

Undiscovered resources are those deposits that have not been pinpointed, but are generally expected to exist based on geologic conditions. The methodology for estimating undiscovered resources examines potential resources in mapped leads. In areas where detailed mapping has been carried out, mapped leads are analyzed by standard statistical techniques to obtain estimates of resources in each basin. Geological risk is assigned by play and also to each individual lead. For each geological basin, the risk factors are calibrated to drilling results. Estimates of undiscovered recoverable resources can be categorized as undiscovered technically recoverable resources (UTRR) and undiscovered economically recoverable resources (UERR).

Those quantities of petroleum which are estimated, on a given date, to be potentially recoverable from undiscovered accumulations by application of future development projects. Prospective resources have both an associated chance of discovery and a chance of development. Prospective resources are further subdivided in accordance with the level certainty associated with recoverable estimates assuming their discovery and development and may be subclassified based on project maturity.

There is no certainty that any portion of the resources will be discovered. If discovered there is no certainty that it will be commercially viable to produce any portion of the resources, but the remaining portion may never be recovered due to the physical/chemical constraints represented by subsurface interaction of fluids and reservoir rock.

SEE PROSPECT, LEAD, PLAY with prospect being the highest order of certainty and play the lowest