Ben Santora

Cover of Earth’s Geological Eras by Ben Santora

Earth’s Geological Eras

by Ben Santora

A short, plain-language walk through 4.6 billion years of Earth history, from the molten Hadean to the ice ages of the Quaternary. Sixteen chapters, one for each eon and period, each opening with a diagram.

It is written for the curious reader who wants the whole story in order: how the continents moved, when life began, what ended it several times over, and how we got here.

Free to read here, in full. Start reading →

Contents

  1. How Geologic Time Is Divided
  2. Hadean Eon4.6–4.0 bya
  3. Archean Eon4.0–2.5 bya
  4. Proterozoic Eon2.5 bya–539 mya
  5. Cambrian Period539–487 mya
  6. Ordovician Period487–443 mya
  7. Silurian Period443–419 mya
  8. Devonian Period419–359 mya
  9. Carboniferous Period359–299 mya
  10. Permian Period299–252 mya
  11. Triassic Period252–201 mya
  12. Jurassic Period201–145 mya
  13. Cretaceous Period145–66 mya
  14. Paleogene Period66–23 mya
  15. Neogene Period23–2.6 mya
  16. Quaternary Period2.6 mya–today

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