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. 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
Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 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
M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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 1032 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			South American Land Mammal Ages		Neogene Mammal Ages of China	Cenozoic Subepochs	Mammal Paleogene Zones
Quaternary	Holocene	Meghalayan										0
		Northgrippian										0.0042
		Greenlandian										0.0082
	Pleistocene	Late Pleistocene	Sheridanian			Lujanian		Nihewanian	Late Pleistocene			0.0117
		Chibanian	Sheridanian						Middle Pleistocene			0.129
			Cudahyan/Sappan									0.21
						Ensenadan						0.3 *
		Calabrian							Early Pleistocene			0.774
			Senecan/Rexroadian									1.4
						Sanandresian	Uquian †					1.7 *
		Gelasian				Sanandresian						1.8
Neogene	Pliocene	Piacenzian				Vorohuean		Yushean	Late Pliocene			2.58
		Piacenzian				Chapadmalalan			Late Pliocene			2.9 *
		Zanclean				Chapadmalalan			Early Pliocene			3.6
						Montehermosan						3.7 *
			Late Hemphillian/late Early Hemphillian/early Early Hemphillian			Montehermosan						4.7
						Huayquerian		Baodean				4.9 *
	Miocene	Messinian							Late Miocene			5.333
		Tortonian										7.246
						Chasicoan						7.9 *
			Late Clarendonian/Early Clarendonian			Chasicoan						9.4
						Mayoan						9.9 *
						Laventan						10.9 *
								Tunggurian				11.1
		Serravallian							Middle Miocene			11.63
			late Late Barstovian/early Late Barstovian/Early Barstovian									12.5
						Colloncuran						13.7 *
		Langhian				Colloncuran		Shanwangian				13.82
		Langhian				Friasian						15.4 *
		Burdigalian				Friasian			Early Miocene			15.98
						Santacrucian						16.2 *
			Late Hemingfordian/Early Hemingfordian									16.3
								Xiejiaan				16.9
						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							Late Oligocene	MP 30/MP 29/MP 28/MP 27/MP 26	MP 25	23.03
				Monroecreekian								23.1 *
				Geringian								24.7 *
		Rupelian							Early Oligocene	MP 24/MP 23/MP 22/MP 21		27.82
						Tinguirirican						28.9 *
												29.5
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian						Late Eocene	MP 20/MP 19/MP 18/MP 17B/MP 17A		33.9
			Late Chadronian/Middle Chadronian/Early Chadronian			Divisaderan						35.9 *
												37
		Bartonian							Middle Eocene	MP 16		37.71
		Bartonian	Late Uintan/Early Uintan							MP 16		39.7
		Lutetian								MP 15/MP 14/MP 13/MP 12/MP 11		41.2
						Mustersan						41.9 *
			Twinbuttean/Blacksforkian/Gardnerbuttian									46.2
		Ypresian							Early Eocene	MP 10/MP 8 + 9/MP 7		47.8
						Casamayoran						47.9 *
			Lostcabinian/Lysitean/Graybullian/Sandcouleean									50.5
					Cf3/Cf2/Cf1							54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1	Riochican			Late Paleocene	MP 6	MP 1 - 5	56
					Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Riochican						56.2
						Itaboraian						56.9 *
						Peligran						58.9 *
		Selandian							Middle Paleocene			59.2
		Selandian			To3/To2/To1				Middle Paleocene			60.9
		Danian							Early Paleocene			61.6
						Tiupampan						62.4 *
					Pu3/Pu2/Pu1	Tiupampan						63.8
												66