Tonian Period: 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.

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.

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Topics

Cryogenian Period Neoproterozoic Era Sturtian Series Dalradian Series Ediacaran Period Katangan Complex Pound Quartzite