Ludlow  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Silurian
 ....Ludlow
NTGorstian
 Ludfordian
Ludlow Member  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Cenozoic
 ...Paleogene
 ....Paleocene
 .....Ludlow Member
RTMontana
 North Dakota
 South Dakota
 Fort Union Formation
SNIn Fort Union Formation. NW and N South Dakota, NE Montana and SW North Dakota. Added to Thesaurus in 1989.
Ludlowville Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Devonian
 ....Middle Devonian
 .....Ludlowville Formation
RTNew York
 Hamilton Group
SNIn Hamilton Group. W and central New York. Includes Ledyard Shale Member; Wanakah Member. Added to Thesaurus in 1989.