Lower Pennsylvanian  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Carboniferous
 ....Pennsylvanian
 .....Lower Pennsylvanian
NTCaseyville Formation
 Crab Orchard Mountains Group
 Gizzard Group
 Haymond Formation
 Lee Formation
 Morrowan
 New River Formation
 Pocahontas Formation
RTMiddle Pennsylvanian
 Upper Pennsylvanian
 Wahoo Limestone
 Manning Canyon Shale