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. 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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126848 collections

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International Chronostratigraphic Timescale			Cambrian of Kazakhstan	Ordovician of Ibero-Bohemia				Ordovician of North America					Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian		Kosovian				Cincinnatian	Gamachian				Harju	Porkuni			443.8
		Katian		Kralodvorian	Bohdalec †				Gamachian					Pirgu			445.2
									Richmondian					Pirgu			446 *
														Vormsi			449.6 *
				Berounian													449.7 *
									Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian							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
						Zahorany †/Vinice	Letna †							Haljala			456.2 *
														Kukruse			456.4 *
								Whiterockian		Canadian †	Chazyan †/Marmor			Kukruse			457 *
														Uhaku	Aluoja †		457.5 *
					Liben †												458 *
	Middle Ordovician	Darriwilian															458.4
				Dobrotivian													458.5 *
				Dobrotivian										Lasnamagi			458.9 *
				Oretanian										Lasnamagi			459.7 *
														Aseri			460.4 *
					Sarka †									Aseri			461.7 *
													Oeland	Kunda			462.9 *
														Kunda	Valaste †/Hunderum		464.3 *
														Volkhov		Langevoja †/Vaana/Saka	467.1 *
		Dapingian			Klabava †												467.3
				Arenigian													468
									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	Ungurian	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