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
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
P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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.

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

This timescale is used in the definition of 126700 collections

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International Chronostratigraphic Timescale			North American Land Mammal Ages	North American Mammal Subages/Zones			Cenozoic Subepochs
								18.5
Paleogene	Oligocene	Chattian	Arikareean	late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian		Late Oligocene	23.03
					Monroecreekian			23.1 *
					Geringian			24.7 *
		Rupelian			Geringian		Early Oligocene	27.82
			Whitneyan					29.5
			Orellan					31.8
	Eocene	Priabonian	Chadronian	Late Chadronian/Middle Chadronian/Early Chadronian			Late Eocene	33.9
		Priabonian	Duchesnean				Late Eocene	37
		Bartonian	Duchesnean				Middle Eocene	37.71
		Bartonian	Uintan	Late Uintan/Early Uintan				39.7
		Lutetian	Uintan	Late Uintan/Early Uintan				41.2
		Lutetian	Bridgerian	Twinbuttean/Blacksforkian/Gardnerbuttian				46.2
		Ypresian	Bridgerian	Twinbuttean/Blacksforkian/Gardnerbuttian			Early Eocene	47.8
			Wasatchian	Lostcabinian/Lysitean/Graybullian/Sandcouleean				50.5
			Clarkforkian			Cf3/Cf2/Cf1		54.9
	Paleocene	Thanetian	Clarkforkian			Cf3/Cf2/Cf1	Late Paleocene	56
		Thanetian	Tiffanian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Late Paleocene	56.2
		Selandian	Tiffanian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Middle Paleocene	59.2
		Selandian	Torrejonian			To3/To2/To1	Middle Paleocene	60.9
		Danian	Torrejonian			To3/To2/To1	Early Paleocene	61.6
		Danian	Puercan			Pu3/Pu2/Pu1	Early Paleocene	63.8
								66