ABSTRACT

The Middle Pennsylvanian (Desmoinesian) Cherokee Group was deposited during a series of transgressions and less extensive regressions and consists mostly of shales separated by thin, persistent limestone beds and local lenticular sandstone units. The sandstones considered in this study include, in ascending order, the Red Fork, Lower Skinner, Upper Skinner and Prue sandstones.*

The Cherokee Group unconformably overlies the Mississippian limestone and underlies the Oswego Limestone. The lower part of the Cherokee thins to the west and north of the study area indicating onlap onto the Mississippian System. Locally the Cherokee sediments were influenced by the paleotopography of the Mississippian limestone. In places the Cherokee sediments were also influenced by paleostructure including differential compaction, structural movement or a combination of the two.

The Red Fork, Skinner and Prue sandstones are believed to be deltaic deposits including interdistributary sandstones and siltstones, channel-fill sandstones and crevasse splay deposits. The Cherokee sea advanced from a southerly direction and the source area for the Cherokee rocks is believed to have been to the east and northeast of the study area.

Locally the sandstones of the Cherokee Group are commercially productive of hydrocarbons and several fields within the study area produce from the Lower Skinner sandstone interval.