The Forest City basin of Missouri, Kansas, Nebraska, and Iowa is the area of the first oil and gas production west of the Mississippi River. Production was found near Paola, Kansas, within a few years of the birth of the American oil industry at Titusville, Pennsylvania.

Initial movements of the Ozark uplift and the Chautauqua arch began in Late Ordovician time. Attendant subsidence in the northern Kansas area formed an ancestral basin which was later bisected by the Nemaha anticline, forming the Salina basin on the west and an unnamed basin on the east. Post-Mississippian, Pre-Atokan peneplanation of the entire region took place before renewed activity along the Nemaha anticline uplifted the area west of the anticline while downwarping east of the Nemaha scarp formed the Forest City basin. Thus, it is defined as a Pennsylvanian-age basin. Movement along the Nemaha structure may have begun as early as pre-St. Peter time but certainly during Early Mississippian time and continued intermittently until at least the Early Permian.

The Cherokee and Forest City basins were separated by a low arch until middle Cherokee time when the Forest City basin filled with sediments and the two basins joined across the Bourbon arch.

Northeast-trending folds developed after Mississippian deposition, whereas previous structural orientation had been toward the northwest.

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