Lower Permian  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Permian
 ....Lower Permian
NTAbo Formation
 Artinskian
 Asselian
 Autunian
 Barakar Stage
 Cherry Canyon Formation
 Leman Sandstone Formation
 Leonardian
 Opeche Shale
 Qixia Formation
 Sakmarian
 Wichita Group
 Wolfcampian
RTGuadalupian
 Kungurian
 Guandacol Formation
 Rotliegendes
 San Gregorio Formation
 Upper Permian
 Middle Permian
 Bird Spring Formation
 Itarare Subgroup
 Laborcita Formation
 Oquirrh Formation
 Pictou Group
 Stockton Formation
 Tensleep Sandstone
 Tubarao Group
 Wild C