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
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
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 127017 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ordovician of Ibero-Bohemia				Ordovician of North America					Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Kosovian				Cincinnatian	Gamachian				Harju	Porkuni			443.8
		Katian		Rawtheyan			Kralodvorian	Bohdalec †				Gamachian					Pirgu			445.2
				Rawtheyan								Richmondian								446 *
				Cautleyan																448.9 *
				Pusgillian																449.3 *
			Caradoc	Streffordian	Onnian †												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								451.1 *
				Cheneyan																451.5 *
				Cheneyan													Oandu			452 *
				Burrellian													Oandu			452.7 *
		Sandbian															Keila	Idavere †		453
					Actonian †															453.2 *
												Turinian								453.7 *
																	Haljala			453.9
					Marshbrookian †	Woolstonian †														454.2 *
					Longvillian †															455.2 *
									Zahorany †/Vinice	Letna †										456.2 *
																	Kukruse			456.4 *
				Aurelucian																456.8 *
											Whiterockian		Canadian †	Chazyan †/Marmor						457 *
					Soudleyan †/Harnagian/Costonian															457.4 *
																	Uhaku	Aluoja †		457.5 *
								Liben †												458 *
	Middle Ordovician	Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn																458.4
							Dobrotivian													458.5 *
							Dobrotivian										Lasnamagi			458.9 *
							Oretanian										Lasnamagi			459.7 *
																	Aseri			460.4 *
				Abereiddian/Early Llanvirn																461.3 *
								Sarka †												461.7 *
																Oeland	Kunda			462.9 *
																	Kunda	Valaste †/Hunderum		464.3 *
																	Volkhov		Langevoja †/Vaana/Saka	467.1 *
		Dapingian						Klabava †												467.3
							Arenigian													468
			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			Tremadocian													477.7
				Migneintian								Stairsian								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