Proterozoic Eon: Quick Facts

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A chart showing the Proterozoic eon on the geologic time scale, divided into Paleoproterozoic, Mesoproterozoic, and Neoproterozoic eras with their respective periods and the millions of years ago each period began, ranging from 2,500 to about 539 million years ago.

Two diagrams compare Earth's prebiotic and modern atmospheres. The top shows a barren landscape with gases like hydrogen, nitrogen, carbon dioxide, and ammonia labeled above, indicating a weakly reducing atmosphere. The bottom shows a lush landscape with plants and animals, labeling oxygen, argon, and other gases, illustrating an oxidizing modern atmosphere.

A detailed geologic time scale chart displaying Earth's history from the Hadean Eon over 4.5 billion years ago to the present, organized by eons, eras, periods, epochs, and ages with color-coded columns and corresponding dates in millions of years.

Major events of the Neoproterozoic Era

Cutaway diagram of a Grand Canyon wall showing layered sedimentary rocks-limestone, shale, sandstone, and composite rocks-with labels indicating Paleozoic rocks (about 252-541 million years old) above older Precambrian rocks, which include Proterozoic (541 million to 2.5 billion years old) and Archean (over 2.5 billion years old) layers. The Colorado River is shown at the base.

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Topics

Paleoproterozoic Era Neoproterozoic Era Labrador Trough Midcontinent rift system Mesoproterozoic Era Grand Canyon Series Belt Series Keweenawan System Huronian System Riphean sequence Archean Eon Hadean Eon

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Precambrian: Proterozoic rock types