488.9 - 471.3 Ma

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

• F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view

The bottom age has 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.

There are intervals in 14 timescales which overlap this one. show

• International Chronostratigraphic Timescale: Early Ordovician epoch, Furongian epoch, Tremadocian age, Stage 10 age, Floian age
• Cambrian Epochs: Late Cambrian epoch
• Ordovician of Britain: Tremadoc epoch, Cressagian age, Arenig epoch, Moridunian age, Migneintian age, Whitlandian age
• Ordovician of the Baltic: Vaana age, Hunderum age, Billingen age, Saka age, Latorp age, Langevoja age, Oeland epoch, Hunneberg age, Varangu age, Valaste age, Pakerort age
• Ordovician of Ibero-Bohemia: Arenigian age, Klabava age
• Ordovician of Australia: Bendigonian age, Warendian age, Lancefieldian age, Chewtonian age
• Ordovician of China: Daobaowan age, Yiyangian age, Hunjiang age, Lianghekou age, Xinchangian age, Dawan age, Ningkuo age
• Ordovician of North America: Skullrockian age, Blackhillsian age, Jeffersonian age, Stairsian age, Cassinian age, Tulean age, Demingian age, Gasconadian age, Canadian age
• Cambrian of China: Taoyuanian age, Niuchehean age
• Cambrian of Australia: Datsonian age, Payntonian age
• Cambrian of Siberia: Tavgian age, Mansian age, Yurakian age, Batyrbaian age, Ketyan age
• Cambrian of Kazakhstan: Ungurian age
• Cambrian of North America: Millardan age, Dresbachian age, Franconian age
• Cambrian of Britain: Trempealeauan age, Merioneth age, Dolgellian age

This interval is used in the definition of 54 collections

A total of 4431 collections with 21176 occurrences lie within this time span