PBDB Timescale

North American Mammal Subages/Zones

The interval definitions in this timescale are derived from the following sources:

M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view
J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 view
W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
F. J. Prevosti, C. O. Romano, A. M. Forasiepi, S. Hemming, R. Bonini, A. M. Candela, E. Cerdeño, M. C. Madozzo Jaén, P. E. Ortiz, F. Pujos, L. Rasia, G. I. Schmidt, M. Taglioretti, R. D. E. MacPhee, and U. F. J. Pardiñas. 2021. New radiometric 40Ar–39Ar dates and faunistic analyses refine evolutionary dynamics of Neogene vertebrate assemblages in southern South America. Scientific Reports 2021(11):9830 view
J. J. Flynn and C. C. Swisher, III. 1995. Cenozoic South American Land Mammal Ages: correlation to global geochronology. Geochronology Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54:317-333 view

There are 13 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 1028 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			Paleogene Mammal Ages of Asia		Obsolete Names for ICS Units			South American Land Mammal Ages
Quaternary	Pleistocene	Late Pleistocene	Sheridanian								Lujanian		0.0117
		Chibanian	Sheridanian										0.129
			Cudahyan/Sappan										0.21
											Ensenadan		0.3 *
		Calabrian											0.774
			Senecan/Rexroadian										1.4
											Sanandresian	Uquian †	1.7 *
		Gelasian									Sanandresian		1.8
Neogene	Pliocene	Piacenzian						Tertiary †			Vorohuean		2.58
		Piacenzian									Chapadmalalan		2.9 *
		Zanclean									Chapadmalalan		3.6
											Montehermosan		3.7 *
			Late Hemphillian/late Early Hemphillian/early Early Hemphillian								Montehermosan		4.7
											Huayquerian		4.9 *
	Miocene	Messinian											5.333
		Tortonian											7.246
											Chasicoan		7.9 *
			Late Clarendonian/Early Clarendonian								Chasicoan		9.4
											Mayoan		9.9 *
											Laventan		10.9 *
		Serravallian											11.63
			late Late Barstovian/early Late Barstovian/Early Barstovian										12.5
											Colloncuran		13.7 *
		Langhian									Colloncuran		13.82
		Langhian									Friasian		15.4 *
		Burdigalian									Friasian		15.98
											Santacrucian		16.2 *
			Late Hemingfordian/Early Hemingfordian								Santacrucian		16.3
			Late Hemingfordian/Early Hemingfordian								Colhuehuapian		17.4 *
			late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian									18.5
		Aquitanian											20.44
		Aquitanian									Deseadan		20.9 *
Paleogene	Oligocene	Chattian				Tabenbulakian	Hsandagolian						23.03
				Monroecreekian									23.1 *
				Geringian									24.7 *
		Rupelian				Kekeamuan							27.82
											Tinguirirican		28.9 *
													29.5
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian			Houldjinian/Ergilian/Ulangochuian							33.9
			Late Chadronian/Middle Chadronian/Early Chadronian								Divisaderan		35.9 *
													37
		Bartonian				Sharamurunian/Irdinmanhan/Arshantan							37.71
		Bartonian	Late Uintan/Early Uintan										39.7
		Lutetian											41.2
											Mustersan		41.9 *
			Twinbuttean/Blacksforkian/Gardnerbuttian										46.2
		Ypresian					Bumbanian						47.8
											Casamayoran		47.9 *
			Lostcabinian/Lysitean/Graybullian/Sandcouleean										50.5
					Cf3/Cf2/Cf1								54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1	Gashatan					Riochican		56
					Ti6/Ti5/Ti4/Ti3/Ti2/Ti1						Riochican		56.2
											Itaboraian		56.9 *
											Peligran		58.9 *
		Selandian											59.2
		Selandian			To3/To2/To1								60.9
		Danian											61.6
											Tiupampan		62.4 *
					Pu3/Pu2/Pu1						Tiupampan		63.8
Cretaceous	Late Cretaceous	Maastrichtian											66
		Campanian											72.1
		Santonian											83.6
		Coniacian											86.3
		Turonian											89.8
		Cenomanian							93.9
	Early Cretaceous	Albian							100.5
		Aptian							113
		Barremian							121.4
		Hauterivian							125.77
		Valanginian							132.6
		Berriasian							139.8
Jurassic	Late Jurassic	Tithonian							145
		Kimmeridgian							149.2
		Oxfordian							154.8
	Middle Jurassic	Callovian							161.5
		Bathonian							165.3
		Bajocian							168.2
		Aalenian							170.9
	Early Jurassic	Toarcian							174.7
		Pliensbachian							184.2
		Sinemurian							192.9
		Hettangian							199.5
Triassic	Late Triassic	Rhaetian							201.4
		Norian							208.5
		Carnian							227
	Middle Triassic	Ladinian							237
	Middle Triassic	Anisian							242
	Early Triassic	Olenekian							247.2
	Early Triassic	Induan							251.2
Permian	Lopingian	Changhsingian							251.902
	Lopingian	Wuchiapingian							Longtanian †	254.14
	Guadalupian	Capitanian								259.51
		Wordian								264.28
		Roadian								266.9
	Cisuralian	Kungurian								273.01
		Artinskian								283.5
		Sakmarian								290.1
		Asselian								293.52
Carboniferous	Pennsylvanian	Gzhelian								298.9
		Kasimovian								303.7
		Moscovian								307
		Bashkirian		315.2
	Mississippian	Serpukhovian		323.2
		Visean		330.9
		Tournaisian		346.7
Devonian	Late Devonian	Famennian		358.9
	Late Devonian	Frasnian		372.2
	Middle Devonian	Givetian		382.7
	Middle Devonian	Eifelian		387.7
	Early Devonian	Emsian		393.3
		Pragian		407.6
		Lochkovian		410.8
Silurian	Pridoli			419.2
	Ludlow	Ludfordian	423
	Ludlow	Gorstian	425.6
	Wenlock	Homerian	427.4
	Wenlock	Sheinwoodian	430.5
	Llandovery	Telychian	433.4
		Aeronian	438.5
		Rhuddanian	440.8
Ordovician	Late Ordovician	Hirnantian	443.8
		Katian	445.2
		Sandbian	453
	Middle Ordovician	Darriwilian	458.4
	Middle Ordovician	Dapingian	467.3
	Early Ordovician	Floian	470
	Early Ordovician	Tremadocian	477.7
Cambrian	Furongian	Stage 10	485.4
		Jiangshanian	489.5
		Paibian	494
	Miaolingian	Guzhangian	Series 3 †	497
		Drumian		500.5
		Wuliuan		Stage 5 †	504.5
													509