era: Quick Facts

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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

erathem geologic time epoch period eon Precambrian How Old Is Earth?geochronology A Journey Through Time Since the Precambrian Astronomical unit metric system nautical mile