[1] The name has also been applied to similar Mississippian strata in the Cumberland Escarpment of eastern Kentucky, though the rocks in that area were later renamed to the Paragon Formation.

[2] Paleosols have also been preserved in a Pennington outcrop at Pound Gap, recording a series of fluctuations in climate between dry and wet conditions.

[3] The Pennington Formation has been inferred to represent a coastal environment transitioning between a Mississippian marine basin and Pennsylvanian coal swamps.

[4] Some parts of the Pennington Formation preserve fossils, including conodonts which are useful for biostratigraphic dating.

Conodont dating indicates that the Pennington Formation formed near the end of the Mississippian subperiod of the Carboniferous period.