A series of seven cross sections across the Central Appalachian Basin in Kentucky, Tennessee, Virginia, West Virginia, and Ohio was constructed in order to determine a stratigraphic and structural framework of the Carboniferous rocks for the basin. Oil and gas well logs, coal-company core descriptions, measured sections, and mapping of surface geology were used to construct these sections. New surface and subsurface faults, folds, and flexures were identified.
New, formal and informal lithostratigraphic nomenclature was introduced to clarify the stratigraphic framework. Formalized nomenclatural changes are (1) elevating Breathitt Formation to Breathitt Group, (2) dropping the Lee Formation, (3) elevating four quartzose sandstone bodies (formerly members of the Lee Formation) to formation status (i.e., Warren Point, Sewanee, Bee Rock, and Corbin Sandstones), (4) including the Rockcastle Sandstone and Livingston Conglomerate of Kentucky as members of the Bee Rock Sandstone Formation, (5) formally replacing the Middlesboro, Chadwell, and White Rocks Members of the Lee Formation with the Sewanee-Warren Point Sandstones, (6) moving the Hensley and Dark Ridge Members of the Lee Formation to the Breathitt Group, and (7) subdividing the Breathitt into five formal (in Kentucky) and two informal (outside Kentucky) formations. The five formal formations are, in ascending order, the Grundy, Pikeville, Hyden, Four Corners, and Princess. The two informal formations, the Bottom Creek and Alvy Creek, occur largely in Virginia and West Virginia. In addition, the Pennington Group is subdivided into the Bluefield, Hinton, Princeton, and Bluestone Formations, which are projected informally into Kentucky from Virginia and West Virginia. The Paragon Formation, restricted to the western belt of outcrop in Kentucky (Ettensohn and others, 1984), is included in the Pennington Group and is largely equivalent to the Bluefield Formation throughout the rest of the basin. The Pinnacle Overlook Sandstone Member of the Lee Formation becomes the Pinnacle Overlook Sandstone of the Pennington Group.
The stratigraphic and structural framework developed in this study will be useful in assessing subsurface coal resources and coal-bed methane potential. Belts of quartzose sandstones (Corbin, Bee Rock, Sewanee, and Warren Point Sandstones) occur at the expense of the coal-bearing rocks of the Breathitt Group; therefore, the distribution of these quartzose sandstones determined in this study can be used to locate areas with greater subsurface resource potential. In addition, the structural framework can be used to explain the distribution of subsurface coal resources. More coal-bearing units are preserved from erosion in synclines and more are eroded at monoclines and anticlines. Basin subsidence also affected coal resources; little coal accumulated in northeastern Kentucky because of reduced subsidence, whereas a greater quantity of coal is present in southeastern Kentucky where greater subsidence occurred.
Digital Object Identifier (DOI)
Chesnut, Donald R. Jr., "Stratigraphic and Structural Framework of the Carboniferous Rocks of the Central Appalachian Basin in Kentucky" (1992). Kentucky Geological Survey Bulletin. 4.