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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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 126778 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of Australia	Cambrian of Kazakhstan	Ordovician of North America
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Bolindian		Cincinnatian	Gamachian				443.8
		Katian		Pirgu						Gamachian				445.2
										Richmondian				446 *
							Eastonian							449 *
				Vormsi										449.6 *
				Vormsi						Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian			449.8 *
				Nabala	Johvi †					Maysvillian				450 *
				Nabala						Edenian				450.4 *
			Viru	Rakvere						Edenian				450.6 *
				Rakvere					Mohawkian	Chatfieldian				451.1 *
				Oandu			Gisbornian							452 *
		Sandbian		Keila	Idavere †									453
				Keila						Turinian				453.7 *
				Haljala										453.9
				Kukruse										456.4 *
				Kukruse					Whiterockian		Canadian †	Chazyan †/Marmor		457 *
				Uhaku	Aluoja †									457.5 *
	Middle Ordovician	Darriwilian		Uhaku			Darriwilian							458.4
				Lasnamagi										458.9 *
				Aseri										460.4 *
			Oeland	Kunda										462.9 *
				Kunda	Valaste †/Hunderum									464.3 *
				Volkhov		Langevoja †/Vaana/Saka								467.1 *
		Dapingian					Yapeenian							467.3
							Castlemainian							468.5 *
										Rangerian				469.1 *
				Billingen						Rangerian				469.3 *
	Early Ordovician	Floian					Chewtonian		Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	470
					Latorp †		Chewtonian							470.1 *
							Bendigonian							471.8 *
							Lancefieldian							473.5 *
				Hunneberg										473.7 *
										Tulean				473.9 *
		Tremadocian						Ungurian		Tulean				477.7
										Stairsian				480.3 *
				Varangu						Stairsian				481.3 *
				Varangu						Skullrockian/Demingian				482 *
				Pakerort										482.2 *
				Pakerort			Warendian							482.8 *
														485.4 *
														486.3
														486.5
														487.5