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
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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126689 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			Obsolete Names for ICS Units	Cenozoic Subepochs
								2.58
								18.5
Paleogene	Oligocene	Chattian	late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian		Tertiary †	Late Oligocene	23.03
				Monroecreekian				23.1 *
				Geringian				24.7 *
		Rupelian		Geringian			Early Oligocene	27.82
		Rupelian					Early Oligocene	29.5
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian				Late Eocene	33.9
		Priabonian					Late Eocene	37
		Bartonian					Middle Eocene	37.71
		Bartonian	Late Uintan/Early Uintan					39.7
		Lutetian	Late Uintan/Early Uintan					41.2
		Lutetian	Twinbuttean/Blacksforkian/Gardnerbuttian					46.2
		Ypresian	Twinbuttean/Blacksforkian/Gardnerbuttian				Early Eocene	47.8
			Lostcabinian/Lysitean/Graybullian/Sandcouleean					50.5
					Cf3/Cf2/Cf1			54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1		Late Paleocene	56
		Thanetian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1		Late Paleocene	56.2
		Selandian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1		Middle Paleocene	59.2
		Selandian			To3/To2/To1		Middle Paleocene	60.9
		Danian			To3/To2/To1		Early Paleocene	61.6
		Danian			Pu3/Pu2/Pu1		Early Paleocene	63.8
								66