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. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 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
J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) view
J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126973 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Harju	Porkuni			443.8
		Katian		Gamachian					Pirgu			445.2
				Richmondian					Pirgu			446 *
				Richmondian					Vormsi			449.6 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian				Vormsi			449.8 *
				Maysvillian					Nabala	Johvi †		450 *
				Edenian					Nabala			450.4 *
				Edenian				Viru	Rakvere			450.6 *
			Mohawkian	Chatfieldian					Rakvere			451.1 *
									Oandu			452 *
		Sandbian							Keila	Idavere †		453
				Turinian					Keila			453.7 *
									Haljala			453.9
									Kukruse			456.4 *
			Whiterockian		Canadian †	Chazyan †/Marmor			Kukruse			457 *
									Uhaku	Aluoja †		457.5 *
	Middle Ordovician	Darriwilian							Uhaku			458.4
									Lasnamagi			458.9 *
									Aseri			460.4 *
								Oeland	Kunda			462.9 *
									Kunda	Valaste †/Hunderum		464.3 *
									Volkhov		Langevoja †/Vaana/Saka	467.1 *
		Dapingian										467.3
				Rangerian								469.1 *
				Rangerian					Billingen			469.3 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †					470
										Latorp †		470.1 *
									Hunneberg			473.7 *
				Tulean								473.9 *
		Tremadocian		Tulean								477.7
				Stairsian								480.3 *
				Stairsian					Varangu			481.3 *
				Skullrockian/Demingian					Varangu			482 *
				Skullrockian/Demingian					Pakerort			482.2 *
												485.4 *
												486.3
												486.5
												487.5