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Which era included the traditional Tertiary Period?

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Messinian Stage — Tertiary Period Gypsum cones, which resulted from the evaporation of the Mediterranean Sea during the Messinian Salinity Crisis, in the Sorbas basin, Spain.

The traditional Tertiary Period was included in the Cenozoic Era.12

While the term Tertiary is now considered obsolete in official geologic time scales—having been replaced by the Paleogene and Neogene periods—it was traditionally defined as the first of two periods within the Cenozoic Era, the second being the Quaternary Period.12