Leonardian  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Permian
 ....Lower Permian
 .....Leonardian
NTBone Spring Limestone
 Clear Fork Group
RTAbo Formation
 San Andres Formation
SNProvincial series, North America. Above Wolfcampian, below Guadalupian.