486.85 - 477.1 Ma

The definition of this interval in the timescale Ordovician of North America is taken from the following source:

• 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

There are intervals in 8 timescales which overlap this one. show

• International Chronostratigraphic Timescale: Tremadocian age, Early Ordovician epoch
• Ordovician of Britain: Migneintian age, Tremadoc epoch, Cressagian age
• Ordovician of the Baltic: Pakerort age, Varangu age, Latorp age, Oeland epoch, Hunneberg age
• Ordovician of Australia: Warendian age, Lancefieldian age
• Ordovician of China: Daobaowan age, Dawan age, Xinchangian age, Hunjiang age, Ningkuo age, Lianghekou age
• Ordovician of North America: Tulean age, Stairsian age, Demingian age, Ibexian epoch, Skullrockian age, Jeffersonian age, Canadian age, Cassinian age
• Cambrian of Siberia: Mansian age
• Cambrian of Kazakhstan: Ungurian age

This interval is no longer in current use

This interval is used in the definition of 122 collections

A total of 2571 collections with 11454 occurrences lie within this time span