PBDB Timescale

Ordovician of North America

The interval definitions in this timescale are derived from the following sources:

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
D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view

There are 14 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 6005 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Cambrian of Siberia
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian							443.8
		Katian		Gamachian							445.2
				Richmondian							446 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian						449.8 *
				Edenian							450.4 *
			Mohawkian	Chatfieldian							451.1 *
		Sandbian		Chatfieldian							453
				Turinian							453.7 *
			Whiterockian		Canadian †	Chazyan †/Marmor					457 *
	Middle Ordovician	Darriwilian									458.4
		Dapingian									467.3
		Dapingian		Rangerian							469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †				470
		Floian		Tulean							473.9 *
		Tremadocian		Tulean							477.7
				Stairsian							480.3 *
				Skullrockian			Demingian †				482 *
							Demingian †	Mansian †			483.55 *
Cambrian	Furongian	Stage 10						Batyrbaian	Tavgian †	Ketyan †/Yurakian	485.4
		Stage 10									487.5
		Jiangshanian									489.5
								Aksaian			490.7 *
								Sakian			492.2 *
		Paibian									494
		Paibian								Ensyan †/Maduan/Nganasanian	494.7 *
	Miaolingian	Guzhangian						Ayusokkanian			497
		Guzhangian						Mayan/Menevian			499.5
		Drumian						Mayan/Menevian			500.5
		Wuliuan						Amgan/Solvan			504.5
	Series 2	Stage 4						Amgan/Solvan			509
								Toyonian	Lenian †		510 *
								Botomian			512.5 *
		Stage 3						Botomian			514
		Stage 3						Atdabanian			515.6 *
	Terreneuvian	Stage 2						Tommotian			521
		Stage 2						Nemakit-Daldynian			525.5
		Fortunian						Nemakit-Daldynian	Manykaian †		529
											538.8