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
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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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.

This timescale is used in the definition of 1028 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			Cenozoic Subepochs	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			Late Pleistocene			0.0117
		Late Pleistocene				Late Pleistocene	Rancholabrean		0.014
		Chibanian				Middle Pleistocene	Rancholabrean		0.129
		Chibanian	Cudahyan/Sappan			Middle Pleistocene	Irvingtonian		0.21
		Calabrian	Cudahyan/Sappan			Early Pleistocene	Irvingtonian		0.774
		Calabrian	Senecan/Rexroadian				Blancan		1.4
		Gelasian							1.8
Neogene	Pliocene	Piacenzian				Late Pliocene			2.58
		Zanclean				Early Pliocene			3.6
		Zanclean	Late Hemphillian/late Early Hemphillian/early Early Hemphillian			Early Pliocene	Hemphillian		4.7
	Miocene	Messinian				Late Miocene			5.333
		Tortonian							7.246
		Tortonian	Late Clarendonian/Early Clarendonian				Clarendonian		9.4
		Serravallian	Late Clarendonian/Early Clarendonian			Middle Miocene	Clarendonian	Cenozoic 5	11.63
		Serravallian	late Late Barstovian/early Late Barstovian/Early Barstovian				Barstovian		12.5
		Langhian							13.82
		Burdigalian				Early Miocene			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
		Aquitanian							20.44
Paleogene	Oligocene	Chattian				Late Oligocene		Cenozoic 4	23.03
				Monroecreekian					23.1 *
				Geringian					24.7 *
		Rupelian		Geringian		Early Oligocene			27.82
							Whitneyan		29.5
							Orellan		31.8
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian			Late Eocene	Chadronian	Cenozoic 3	33.9
		Priabonian				Late Eocene	Duchesnean		37
		Bartonian				Middle Eocene	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			Early Eocene	Bridgerian		47.8
			Lostcabinian/Lysitean/Graybullian/Sandcouleean				Wasatchian		50.5
					Cf3/Cf2/Cf1		Clarkforkian		54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1	Late Paleocene	Clarkforkian	Cenozoic 1	56
		Thanetian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Late Paleocene	Tiffanian		56.2
		Selandian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Middle Paleocene	Tiffanian		59.2
		Selandian			To3/To2/To1	Middle Paleocene	Torrejonian		60.9
		Danian			To3/To2/To1	Early Paleocene	Torrejonian		61.6
		Danian			Pu3/Pu2/Pu1	Early Paleocene	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							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	Cambrian 4	497
		Drumian	Cambrian 4	500.5
		Wuliuan	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