Paleozoic
Paleozoic era
Age of Reptiles
Mesozoic
Mesozoic era
Carboniferous period
Carboniferous
Age of Mammals
Cenozoic era
Cenozoic
Tertiary
Tertiary period
Phanerozoic
Phanerozoic eon
Phanerozoic aeon
Quaternary
Age of Man
Quaternary period
Siderian
Rhyacian
Cambrian period
Cambrian
Ediacaran
Archaeozoic
Orosirian
Recent
Recent epoch
Stenian
Holocene
Holocene epoch
Cryogenian
giga-annum
saros
Calymmian
Jurassic
Permian period
Permian
Silurian
Upper Carboniferous period
Jurassic period
Pennsylvanian period
Pennsylvanian
Silurian period
neros
Upper Carboniferous
tertiary
Devonian
Eocene
Permian-Triassic extinction
kya
Triassic period
Triassic
1530s
Cisuralian
Triassic-Jurassic extinction event
millennian
Tonian
millennial
Eocene epoch
eon
Glacial epoch
Pleistocene
Pleistocene epoch
Ectasian
millenary
millennium
century
Statherian
gigayear
C17
multi-billion
Acadian
anomalistic year
Nectarian
Eratosthenian
Pannotia
2080s
submillennial
Eoarchean
Ordovician
Mesoarchean
Hettangian
Stennian
Paleoarchean
2160s
Precambrian
megayear
quadringentenary
Archean aeon
Archeozoic
trimillennial
Archean
Archean eon
Archaeozoic aeon