Stratigraphy and Depositional Environments of Cherokee Group (Desmoinesian, Middle Pennsylvanian), Central Cherokee Basin, Southeast Kansas
Michael D. Staton, Lawrence L. Brady, Anthony W. Walton
Correlation from geophysical
well logs of radioactive black shales, which
extend throughout the basin and into the Sedgwick and Forest City basins,
provided the basis for division of the Cherokee Group into 11 stratigraphic
intervals. Black shale units below the Fort Scott Limestone and the Verdigris
Limestone, and above the Tebo coal are the most extensive and easily
recognizable markers. The "Tebo" marker might be considered as a possible
boundary between the Krebs and Cabaniss Formations owing to lateral
extensiveness, mappability, and stratigraphic location near a distinct
lithologic change. Cross sections indicate that the basin subsided during
deposition of the Krebs Formation. Stratigraphic intervals in the overlying
Cabaniss Formation are relatively uniform in thi kness, suggesting little or no
subsidence during deposition. Onlap upon the Nemaha ridge occurred during Krebs
and much of Cabaniss deposition. Stratigraphic markers that overlap the ridge
and extend into the Sedgwick basin indicate one depositional province.
Core, well-log, and well-sample studies show that lithologic characteristics within the basin appear similar to outcrop features. Basin strata are dominated by shales and sandstones with interbedded coals and thin limestones. Net-sandstone isolith maps reveal the presence of a deltaic complex characterized by both stacking and offset of major sandstone bodies. The amount of limestone significantly increases along the eastern flank of the Nemaha ridge.
AAPG Search and Discovery Article #91039©1987 AAPG Mid-Continent Section Meeting, Tulsa, Oklahoma, September 27-29, 1987.