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Geologic Age Range Search by geologic age

ERA	PERIOD		EPOCH
Cenozoic	Quaternary		Holocene
	Quaternary		Pleistocene
	Tertiary	late (Neogene)	Pliocene
		late (Neogene)	Miocene
		early (Paleogene)	Oligocene
			Eocene
			Paleocene
Mesozoic	Cretaceous		Late
	Cretaceous		Early
	Jurassic		Late
			Middle
			Early
	Triassic		Late
			Middle
			Early
Paleozoic	Permian		Late
			Middle
			Early
	Carbonif.	Penn.	Late
			Middle
			Early
		Miss.	Late
			Middle
			Early
	Devonian		Late
			Middle
			Early
	Silurian		Late
	Silurian		Early
	Ordovician		Late
			Middle
			Early
	Cambrian		Late
			Middle
			Early
Precamb. **	Proterozoic **		Late *
			Middle *
			Early *
	Archean **

** Eon. * Era. Learn more

Welcome

The U.S. Geologic Names Lexicon ("Geolex"), a National compilation of names and descriptions of geologic units.

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