440.1 - 422.5 Ma

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

• F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view

The top and bottom ages 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.

There are intervals in 5 timescales which overlap this one. show

• International Chronostratigraphic Timescale: Telychian age, Gorstian age, Wenlock epoch, Aeronian age, Homerian age, Pridoli epoch, Sheinwoodian age, Ludlow epoch, Ludfordian age, Llandovery epoch
• Silurian of the Baltic: Paadla age, Rootsikula age, Kaugetuma age, Jaani age, Adavere age, Kuressaare age, Jaagarahu age, Raikkula age
• Silurian Ages of Europe: Whitwellian age, Gleedonian age
• Silurian of England: Elton age, Wych age, Tickwood age, Bringewood age, Downton Castle age, Buildwas age, Woolhope age, Red Downtonian age, Coalbrookdale age, Wenlock (England) age, Temeside Shales age, Cowleigh Park age
• Silurian of North America: Ontarian age, Alexandrian age, Lockportian age

This interval is used in the definition of 15 collections

A total of 6779 collections with 52603 occurrences lie within this time span