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
F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) 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
A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 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			European Faunal Units	Obsolete Names for ICS Units			North American Land Mammal Ages	Ten Million Year Bins
Quaternary	Holocene	Meghalayan								Saintaugustinean	Cenozoic 6	0
		Meghalayan								Santarosean		0.0004
		Northgrippian										0.0042
		Greenlandian										0.0082
	Pleistocene	Late Pleistocene	Sheridanian									0.0117
		Late Pleistocene								Rancholabrean		0.014
		Chibanian								Rancholabrean		0.129
		Chibanian	Cudahyan/Sappan							Irvingtonian		0.21
		Calabrian	Cudahyan/Sappan							Irvingtonian		0.774
		Calabrian	Senecan/Rexroadian							Blancan		1.4
		Gelasian										1.8
Neogene	Pliocene	Piacenzian				Villanyian	Tertiary †					2.58
		Piacenzian				Ruscinian						3.1 *
		Zanclean										3.6
		Zanclean	Late Hemphillian/late Early Hemphillian/early Early Hemphillian							Hemphillian		4.7
	Miocene	Messinian				Turolian						5.333
		Tortonian				Turolian						7.246
						Vallesian						8.7
			Late Clarendonian/Early Clarendonian			Vallesian				Clarendonian		9.4
		Serravallian	Late Clarendonian/Early Clarendonian			Astaracian				Clarendonian	Cenozoic 5	11.63
		Serravallian	late Late Barstovian/early Late Barstovian/Early Barstovian							Barstovian		12.5
		Langhian										13.82
		Burdigalian				Orleanian						15.98
			Late Hemingfordian/Early Hemingfordian							Hemingfordian		16.3
			late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian						Arikareean		18.5
						Agenian						20
		Aquitanian				Agenian						20.44
Paleogene	Oligocene	Chattian									Cenozoic 4	23.03
				Monroecreekian								23.1 *
				Geringian								24.7 *
		Rupelian		Geringian								27.82
										Whitneyan		29.5
										Orellan		31.8
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian							Chadronian	Cenozoic 3	33.9
		Priabonian								Duchesnean		37
		Bartonian								Duchesnean		37.71
		Bartonian	Late Uintan/Early Uintan							Uintan		39.7
		Lutetian	Late Uintan/Early Uintan							Uintan	Cenozoic 2	41.2
		Lutetian	Twinbuttean/Blacksforkian/Gardnerbuttian							Bridgerian		46.2
		Ypresian	Twinbuttean/Blacksforkian/Gardnerbuttian							Bridgerian		47.8
			Lostcabinian/Lysitean/Graybullian/Sandcouleean							Wasatchian		50.5
					Cf3/Cf2/Cf1					Clarkforkian		54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1					Clarkforkian	Cenozoic 1	56
		Thanetian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1					Tiffanian		56.2
		Selandian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1					Tiffanian		59.2
		Selandian			To3/To2/To1					Torrejonian		60.9
		Danian			To3/To2/To1					Torrejonian		61.6
		Danian			Pu3/Pu2/Pu1					Puercan		63.8
Cretaceous	Late Cretaceous	Maastrichtian									Cretaceous 8	66
		Campanian									Cretaceous 7	72.1
		Santonian									Cretaceous 6	83.6
		Coniacian										86.3
		Turonian										89.8
		Cenomanian									Cretaceous 5	93.9
	Early Cretaceous	Albian									Cretaceous 4	100.5
		Aptian									Cretaceous 3	113
		Barremian									Cretaceous 2	121.4
		Hauterivian									Cretaceous 2	125.77
		Valanginian									Cretaceous 1	132.6
		Berriasian									Cretaceous 1	139.8
Jurassic	Late Jurassic	Tithonian									Jurassic 6	145
		Kimmeridgian									Jurassic 5	149.2
		Oxfordian										154.8
	Middle Jurassic	Callovian										161.5
		Bathonian						Jurassic 4	165.3
		Bajocian						Jurassic 4	168.2
		Aalenian						Jurassic 3	170.9
	Early Jurassic	Toarcian						Jurassic 3	174.7
		Pliensbachian						Jurassic 2	184.2
		Sinemurian						Jurassic 1	192.9
		Hettangian						Jurassic 1	199.5
Triassic	Late Triassic	Rhaetian						Triassic 4	201.4
		Norian						Triassic 4	208.5
		Carnian						Triassic 3	227
	Middle Triassic	Ladinian						Triassic 2	237
	Middle Triassic	Anisian						Triassic 2	242
	Early Triassic	Olenekian						Triassic 1	247.2
	Early Triassic	Induan						Triassic 1	251.2
Permian	Lopingian	Changhsingian						Permian 4	251.902
	Lopingian	Wuchiapingian							Longtanian †		254.14
	Guadalupian	Capitanian									259.51
		Wordian									264.28
		Roadian						Permian 3			266.9
	Cisuralian	Kungurian						Permian 2			273.01
		Artinskian									283.5
		Sakmarian									290.1
		Asselian						Permian 1			293.52
Carboniferous	Pennsylvanian	Gzhelian						Carboniferous 5			298.9
		Kasimovian						Carboniferous 5			303.7
		Moscovian						Carboniferous 4			307
		Bashkirian						Carboniferous 4			315.2
	Mississippian	Serpukhovian				Carboniferous 3		323.2
		Visean				Carboniferous 2		330.9
		Tournaisian				Carboniferous 1		346.7
Devonian	Late Devonian	Famennian				Devonian 5		358.9
	Late Devonian	Frasnian		Devonian 4		372.2
	Middle Devonian	Givetian		Devonian 3		382.7
	Middle Devonian	Eifelian		Devonian 3		387.7
	Early Devonian	Emsian		Devonian 2		393.3
		Pragian		Devonian 1		407.6
		Lochkovian		Devonian 1		410.8
Silurian	Pridoli			Silurian 2		419.2
	Ludlow	Ludfordian				423
	Ludlow	Gorstian				425.6
	Wenlock	Homerian				427.4
	Wenlock	Sheinwoodian	430.5
	Llandovery	Telychian	Silurian 1	433.4
		Aeronian		438.5
		Rhuddanian		440.8
Ordovician	Late Ordovician	Hirnantian	Ordovician 5	443.8
		Katian	Ordovician 5	445.2
		Sandbian	Ordovician 4	453
	Middle Ordovician	Darriwilian	Ordovician 3	458.4
	Middle Ordovician	Dapingian	Ordovician 2	467.3
	Early Ordovician	Floian	Ordovician 2	470
	Early Ordovician	Tremadocian	Ordovician 1	477.7
Cambrian	Furongian	Stage 10	Cambrian 5	485.4
		Jiangshanian		489.5
		Paibian		494
	Miaolingian	Guzhangian	Series 3 †	Cambrian 4	497
		Drumian		Cambrian 4	500.5
		Wuliuan		Stage 5 †	Cambrian 3	504.5
	Series 2	Stage 4			Cambrian 3	509
	Series 2	Stage 3			Cambrian 2	514
	Terreneuvian	Stage 2			Cambrian 2	521
	Terreneuvian	Fortunian			Cambrian 1	529
												538.8