What are some eight-letter geological periods?

22 of the 90 geological periods in Icillion have exactly 8 letters, for example Jurassic, Triassic and Cambrian.

Which eight-letter geological periods start with C?

C is the most common first letter here, with 3 names, such as Cambrian, Cenozoic and Chattian.

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These are the eight-letter geological periods in Icillion: 22 names, from “Cambrian” to “Zanclean”.

22 of the 90 geological periods have exactly 8 letters (24%).
Most start with C (3), L (3) and R (3).
Only names of one word are counted, and only their letters: spaces, hyphens and apostrophes are not.

What are some eight-letter geological periods?: 22 of the 90 geological periods in Icillion have exactly 8 letters, for example Jurassic, Triassic and Cambrian.
Which eight-letter geological periods start with C?: C is the most common first letter here, with 3 names, such as Cambrian, Cenozoic and Chattian.

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