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
J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) view
M. Harzhauser and W. E. Piller. 2004. Integrated stratigraphy of the Sarmatian (Upper Middle Miocene) in the western Central Paratethys. Stratigraphy 1(1):65-86 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 127017 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of Britain				Ten Million Year Bins
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Ashgill	Hirnantian			Ordovician 5	443.8
		Katian		Gamachian					Rawtheyan				445.2
				Richmondian					Rawtheyan				446 *
									Cautleyan				448.9 *
									Pusgillian				449.3 *
								Caradoc	Streffordian	Onnian †			449.6 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian								449.8 *
				Edenian									450.4 *
			Mohawkian	Chatfieldian									451.1 *
									Cheneyan				451.5 *
									Burrellian				452.7 *
		Sandbian										Ordovician 4	453
										Actonian †			453.2 *
				Turinian						Actonian †			453.7 *
										Marshbrookian †	Woolstonian †		454.2 *
										Longvillian †			455.2 *
									Aurelucian				456.8 *
			Whiterockian		Canadian †	Chazyan †/Marmor							457 *
										Soudleyan †/Harnagian/Costonian			457.4 *
	Middle Ordovician	Darriwilian						Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			Ordovician 3	458.4
		Darriwilian							Abereiddian/Early Llanvirn			Ordovician 3	461.3 *
		Dapingian							Abereiddian/Early Llanvirn			Ordovician 2	467.3
								Arenig	Fennian				468.4 *
				Rangerian									469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †						470
				Blackhillsian					Whitlandian				471.1 *
				Tulean					Whitlandian				473.9 *
									Moridunian				474.3 *
		Tremadocian						Tremadoc	Migneintian			Ordovician 1	477.7
				Stairsian					Migneintian				480.3 *
				Stairsian					Cressagian				480.8 *
				Skullrockian/Demingian					Cressagian				482 *
				Skullrockian/Demingian									485 *
													485.4
													487.5