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
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

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 127243 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of the Baltic				Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Harju	Porkuni			Ashgill	Hirnantian			443.8
		Katian		Gamachian					Pirgu				Rawtheyan			445.2
				Richmondian									Rawtheyan			446 *
													Cautleyan			448.9 *
													Pusgillian			449.3 *
									Vormsi			Caradoc	Streffordian	Onnian †		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												451.1 *
													Cheneyan			451.5 *
									Oandu				Cheneyan			452 *
									Oandu				Burrellian			452.7 *
		Sandbian							Keila	Idavere †						453
														Actonian †		453.2 *
				Turinian												453.7 *
									Haljala							453.9
														Marshbrookian †	Woolstonian †	454.2 *
														Longvillian †		455.2 *
									Kukruse							456.4 *
													Aurelucian			456.8 *
			Whiterockian		Canadian †	Chazyan †/Marmor										457 *
														Soudleyan †/Harnagian/Costonian		457.4 *
									Uhaku	Aluoja †				Soudleyan †/Harnagian/Costonian		457.5 *
	Middle Ordovician	Darriwilian							Uhaku			Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
									Lasnamagi							458.9 *
									Aseri							460.4 *
									Aseri				Abereiddian/Early Llanvirn			461.3 *
								Oeland	Kunda							462.9 *
									Kunda	Valaste †/Hunderum						464.3 *
									Volkhov		Langevoja †/Vaana/Saka					467.1 *
		Dapingian														467.3
												Arenig	Fennian			468.4 *
				Rangerian												469.1 *
				Rangerian					Billingen							469.3 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †									470
										Latorp †						470.1 *
													Whitlandian			471.1 *
									Hunneberg							473.7 *
				Tulean												473.9 *
													Moridunian			474.3 *
		Tremadocian										Tremadoc	Migneintian			477.7
				Stairsian									Migneintian			480.3 *
													Cressagian			480.8 *
									Varangu							481.3 *
				Skullrockian/Demingian					Varangu							482 *
									Pakerort							482.2 *
									Pakerort							485 *
																485.4 *
																486.3
																486.5
																487.5