What are some nine-letter geological periods?

19 of the 90 geological periods in Icillion have exactly 9 letters, for example Paleozoic, Paleogene and Oligocene.

Which nine-letter geological periods start with C?

C is the most common first letter here, with 4 names, such as Calabrian, Calymmian, Campanian and Chibanian.

Science · lists

Stuck on a crossword or a word game? 19 geological periods have exactly 9 letters, from “Calabrian” to “Tortonian”.

19 of the 90 geological periods have exactly 9 letters (21%).
Most start with C (4), T (4) and O (3).
Only names of one word are counted, and only their letters: spaces, hyphens and apostrophes are not.

What are some nine-letter geological periods?: 19 of the 90 geological periods in Icillion have exactly 9 letters, for example Paleozoic, Paleogene and Oligocene.
Which nine-letter geological periods start with C?: C is the most common first letter here, with 4 names, such as Calabrian, Calymmian, Campanian and Chibanian.

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