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
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.

This timescale is used in the definition of 1028 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			Mammal Paleogene Zones
Quaternary	Holocene	Meghalayan						0
		Northgrippian						0.0042
		Greenlandian						0.0082
	Pleistocene	Late Pleistocene	Sheridanian					0.0117
		Chibanian	Sheridanian					0.129
		Chibanian	Cudahyan/Sappan					0.21
		Calabrian	Cudahyan/Sappan					0.774
		Calabrian	Senecan/Rexroadian					1.4
		Gelasian						1.8
Neogene	Pliocene	Piacenzian						2.58
		Zanclean						3.6
		Zanclean	Late Hemphillian/late Early Hemphillian/early Early Hemphillian					4.7
	Miocene	Messinian						5.333
		Tortonian						7.246
		Tortonian	Late Clarendonian/Early Clarendonian					9.4
		Serravallian	Late Clarendonian/Early Clarendonian					11.63
		Serravallian	late Late Barstovian/early Late Barstovian/Early Barstovian					12.5
		Langhian						13.82
		Burdigalian						15.98
			Late Hemingfordian/Early Hemingfordian					16.3
			late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian				18.5
		Aquitanian						20.44
Paleogene	Oligocene	Chattian				MP 30/MP 29/MP 28/MP 27/MP 26	MP 25	23.03
				Monroecreekian				23.1 *
				Geringian				24.7 *
		Rupelian		Geringian		MP 24/MP 23/MP 22/MP 21		27.82
		Rupelian				MP 24/MP 23/MP 22/MP 21		29.5
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian			MP 20/MP 19/MP 18/MP 17B/MP 17A		33.9
		Priabonian				MP 20/MP 19/MP 18/MP 17B/MP 17A		37
		Bartonian				MP 16		37.71
		Bartonian	Late Uintan/Early Uintan			MP 16		39.7
		Lutetian	Late Uintan/Early Uintan			MP 15/MP 14/MP 13/MP 12/MP 11		41.2
		Lutetian	Twinbuttean/Blacksforkian/Gardnerbuttian			MP 15/MP 14/MP 13/MP 12/MP 11		46.2
		Ypresian	Twinbuttean/Blacksforkian/Gardnerbuttian			MP 10/MP 8 + 9/MP 7		47.8
			Lostcabinian/Lysitean/Graybullian/Sandcouleean					50.5
					Cf3/Cf2/Cf1			54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1	MP 6	MP 1 - 5	56
		Thanetian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	MP 6		56.2
		Selandian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1			59.2
		Selandian			To3/To2/To1			60.9
		Danian			To3/To2/To1			61.6
		Danian			Pu3/Pu2/Pu1			63.8
								66