ABSTRACT

In southern Lincoln, and northern Pottawatomie and Seminole Counties, Oklahoma, the Middle Pennsylvanian (Desmoinesian) "Cherokee" Group, unconformably overlies Mississippian Limestone of Osagean age, and consists of cyclic sequences of shales, sandstones, thin limestones, and at least one coastal coal bed. The thin limestones and coal bed serve as markers for division of the "Cherokee" Group into transgressive-regressive couplets. The sandstone bodies were deposited during regressions and were preserved during the following marine transgression. In ascending order these sandstone are known as the Bartlesville, Red Fork, Lower Skinner, Upper Skinner, and Prue.

The "Cherokee" sandstones, which are thought to be representative of deltaic environments, in the study area, are classified as distributary channel and non-channel deposits. The latter category corresponds to delta-fringe, with related subenvironments of interdistributary bay, distributary mouth, and delta front. All sandstones vary in trend. The Upper Skinner Sandstone contains a major east-west trend, and a number of Prue, Red Fork, and Bartlesville sandstone bodies trend north-south. Well-developed sandstones in complex trends represent multilateral and multistoried units.

Structural features include a north-northeast-trending fault zone and gentle noses and saddles. An en echelon fault zone at the surface reflects the fault zone along which some dipslip displacement accompanied the dominant strike-slip displacement. Variations in interval thicknesses probably result from contemporaneous fault movement, reciprocity in sedimentation, and differential compaction associated with variations in sandstone development.

Production of hydrocarbons from "Cherokee" sandstones are from stratigraphic and structural-stratigraphic traps.