Willwood Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Cenozoic
 ...Paleogene
 ....Eocene
 .....lower Eocene
 ......Willwood Formation
RTWyoming
SNVariegated shales and hornblende-bearing sandstones conformably overlying Polecat Bench Formation near center of Bighorn Basin. In N Wyoming.