Distinctive differences between Late Desmoinesian to early Missourian cyclic deposits on opposite shores of the Pennsylvanian Arkoma seaway were noted during outcrop mapping in eastern Oklahoma.

The north shore deposits conform to the classical Mid-Continent Pennsylvanian cyclothem. A regressive blanket sandstone is succeeded in turn by underclay, coal, and carbonaceous shale, transgressive calcareous shale and/or limestone, black fissile shale with phosphate nodules, and finally, gray shale with calcareous to sideritic inclusions that becomes upward increasingly silty to sandy.

The south shore deposits that border the Ouachita and Arbuckle uplifts in southeastern Oklahoma reveal a more symmetrical cycle than for the preceding. Both transgressive and regressive sandstones are present, and, although exceedingly lenticular, converge northward to enclose a fluviatile tongue of red beds and conglomeratic lenses. The subjacent and superjacent transgressive marine wedges contain fossiliferous gray to black shales. Limestones are usually thin and developed near tops and bottoms of shale sequences.

Seaway deposits are much more variable. High sea-level phase is characterized by subtidal gray shale with subordinate bioturbated siltstone to sandstone. A low sea-level phase commonly consists of intertonguing north and south shore deposits.

Effects of eustatic oscillations of sea level were imprinted on a episodically subsiding depositional trough. Many stratigraphic horizons that reflect sea-level reversals are useful for regional correlations. Application of this concept to the polycyclic Holdenville formation of Hughes County indicates its northward continuation as the Memorial shale and the overlying Jenks and Tulsa sandstones and associated shales of Tulsa County previously miscorrelated with the Seminole Formation. In the subsurface these sandstones become the oil productive Cleveland sandstones. These correlations are supported by fossil determinations.

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