Mineral and petroleum resources within the Katmai area have not been investigated other than through reconnaissance studies and local explorations. Only a small part of the park has been subject to detailed geologic study, and most information has been obtained from a few widely spaced reconnaissance-type traverses.

The Alaska Peninsula petroleum province extends through the eastern part of the park area, and the Nushagak-Bristol Bay province underlies the western part. The Alaska Peninsula province produces oil and gas in the Cook Inlet area north of the park. A 1959 study of the park area by the U.S. Geological Survey states that the entire region has been subjected to intense volcanic activity, and it is unlikely that favorable petroleum strata can be reached at practical drilling depths on most of the structures that would be drilled.