Spoon Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Carboniferous
 ....Pennsylvanian
 .....Middle Pennsylvanian
 ......Spoon Formation
RTIllinois
 Kewanee Group
SNIn Kewanee Group. Added to Thesaurus in 1985.