what is the second one?
It is the current and most recent of the three geological eras of the Phanerozoic Eon.
Cenozoic
 is the current and most recent of the three geological eras of the Phanerozoic Eon.
where was the material that was eroded by the colorado river deposited Regions in the Mesozoic and Cenozoic
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Cenozoic [SEP] Introduction
The Cenozoic Era ( ) meaning "new life" is the current and most recent of the three geological eras of the Phanerozoic Eon. It follows the Mesozoic Era and extends from 66 million years ago to the present day. It is generally believed to have started on the first day of the Cretaceous–Paleogene extinction event (also referred to as the K-Pg, or K-T, extinction event) when an asteroid hit the Earth. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammals – the Eutherians (placentals) in the northern hemisphere and the Metatherians (marsupials, now mainly restricted to Australia) in the southern hemisphere.