Tonian
Cryogenian
Ediacaran
Orosirian
Statherian
Siderian
Rhyacian
Stennian
Devonian
Ectasian
Holocene
Calymmian
Guadalupian
Stenian
Phanerozoic
Phanerozoic aeon
Phanerozoic eon
Cambrian
Iapetus
Pliocene
Lopingian
Jurassic
Paleolithic
Neoproterozoic
Paleogene
Carboniferous
Carboniferous period
Triassic-Jurassic extinction event
-cene
tertiary
Ordovician
Paleoproterozoic
finicretaceous
decamillennium
Acadian
Campanian
Silurian
Hettangian
Paleocene
Miocene
Triassic
Triassic period
Furongian
Eocene
Eratosthenian
K-T boundary
Ubaid
Mesoarchean
Jurassic period
Ypresian
period
Permian-Triassic extinction
lower boundary
Cenozoic
Upper Carboniferous
Pennsylvanian
paleolimnological
Leptolithic
Mesozoic
New Stone Age
Upper Carboniferous period
Pennsylvanian period
paleochronology
Maastrichtian
Paleogenic
Paleozoic
Coniacian
Archean
Archaeozoic aeon
-zoic
Northgrippian
Archeozoic
Archean eon
Archean aeon
Archaean
Cisuralian
Cenomanian
Cretaceous
Archaeozoic
Neolithic
Permian
Archeozoic eon
millennial
millennian
C15
Aurignacian
Lower Paleozoic
Selandian
Thanetian
Cambrian period
Danian
Permian period