Onondaga Limestone  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Devonian
 ....Middle Devonian
 .....Onondaga Limestone
RTVirginia
 Pennsylvania
 New York
 Maryland
 West Virginia
 Hamilton Group
 Tioga Bentonite
SNIncludes Springfield Center Member, Babcock Hill Member, Edgecliff Member, Nedrow Member, Moorehouse Member, Seneca Member, Needmore Shale, Selinsgrove Limestone. W Maryland, New York, Pennsylvania, Western Virginia, and N West Virginia.