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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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 126884 collections

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International Chronostratigraphic Timescale			Ordovician of China			Ordovician of the Baltic				Ordovician of North America
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Harju	Porkuni			Cincinnatian	Gamachian				443.8
		Katian	Chientangkiangian				Pirgu				Gamachian				445.2
			Chientangkiangian								Richmondian				446 *
			Neichianshanian/Hanjiang												449.5
							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								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	Darriwilian	Guniu †/Hulo			Uhaku								458.4
							Lasnamagi								458.9 *
							Aseri								460.4 *
						Oeland	Kunda								462.9 *
								Valaste †/Hunderum							464.3 *
				Hunjiang †	Dawan †/Daobaowan/Ningkuo										466.3 *
							Volkhov		Langevoja †/Vaana/Saka						467.1 *
		Dapingian	Dapingian												467.3
											Rangerian				469.1 *
							Billingen				Rangerian				469.3 *
	Early Ordovician	Floian	Yiyangian							Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	470
								Latorp †							470.1 *
							Hunneberg								473.7 *
											Tulean				473.9 *
		Tremadocian	Xinchangian												477.7
					Lianghekou †										477.9 *
											Stairsian				480.3 *
							Varangu				Stairsian				481.3 *
							Varangu				Skullrockian/Demingian				482 *
							Pakerort				Skullrockian/Demingian				482.2 *
															485.4 *
															486.3
															486.5
															487.5