PBDB Interval

International Chronostratigraphic Timescale

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

K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
M. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
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

There are 59 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 127258 collections

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International Chronostratigraphic Timescale			Mammal Paleogene Zones		North American Land Mammal Ages	North American Mammal Subages/Zones
									18.5
Paleogene	Oligocene	Chattian	MP 30/MP 29/MP 28/MP 27/MP 26	MP 25	Arikareean	late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian		23.03
							Monroecreekian		23.1 *
							Geringian		24.7 *
		Rupelian	MP 24/MP 23/MP 22/MP 21				Geringian		27.82
					Whitneyan				29.5
					Orellan				31.8
	Eocene	Priabonian	MP 20/MP 19/MP 18/MP 17B/MP 17A		Chadronian	Late Chadronian/Middle Chadronian/Early Chadronian			33.9
		Priabonian	MP 20/MP 19/MP 18/MP 17B/MP 17A		Duchesnean				37
		Bartonian	MP 16		Duchesnean				37.71
		Bartonian	MP 16		Uintan	Late Uintan/Early Uintan			39.7
		Lutetian	MP 15/MP 14/MP 13/MP 12/MP 11		Uintan	Late Uintan/Early Uintan			41.2
		Lutetian	MP 15/MP 14/MP 13/MP 12/MP 11		Bridgerian	Twinbuttean/Blacksforkian/Gardnerbuttian			46.2
		Ypresian	MP 10/MP 8 + 9/MP 7		Bridgerian	Twinbuttean/Blacksforkian/Gardnerbuttian			47.8
					Wasatchian	Lostcabinian/Lysitean/Graybullian/Sandcouleean			50.5
					Clarkforkian			Cf3/Cf2/Cf1	54.9
	Paleocene	Thanetian	MP 6	MP 1 - 5	Clarkforkian			Cf3/Cf2/Cf1	56
		Thanetian	MP 6		Tiffanian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	56.2
		Selandian			Tiffanian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	59.2
		Selandian			Torrejonian			To3/To2/To1	60.9
		Danian			Torrejonian			To3/To2/To1	61.6
		Danian			Puercan			Pu3/Pu2/Pu1	63.8
									66