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
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
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
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 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.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 127258 collections

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