635 - 538.8 Ma

The definition of this interval in the timescale Obsolete Precambrian Ages 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 1 timescales which overlap this one. show

• Obsolete Precambrian Ages: Wonokan age, Poundian age

This interval is no longer in current use

This interval is used in the definition of 16 collections

A total of 471 collections with 1921 occurrences lie within this time span