PBDB Interval Range

470 - 451.1 Ma

International Chronostratigraphic Timescale			Ordovician of North America
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 *
								485.4
								487.5