The Marietta syncline is complementary to the Wichita-Criner Hills arch, one of the most prolific oil-producing areas of Oklahoma. The middle Pennsylvanian producing sands of the Wichita-Criner Hills arch are present in the Marietta syncline and are separated from the pre-Pennsylvanian strata by an important unconformity. Oil shows have also been found in the pre-Pennsylvanian formations. The NE flank of the Marietta syncline must be considered an unproved and virtually untested petroliferous province. The presence of a small producing field 10 mi. SW in the syncline proper, known reservoir strata, unconformities, and hydrocarbon shows should be enough to justify further exploration.