Eras

Phanerozoic

fan-er-uh-ZOH-ik

Citation Formats

General Reference

Earth and Environment Atlas. "Phanerozoic." Accessed August 29, 2026. https://dev-earth.interactiveatlas.org/eras/phanerozoic.

APA Style

Earth and Environment Atlas. (n.d.). Phanerozoic. Retrieved August 29, 2026, from https://dev-earth.interactiveatlas.org/eras/phanerozoic

BibTeX

@misc{earthandenvironmentatlas-phanerozoic,
  author = {Earth and Environment Atlas},
  title = {Phanerozoic},
  year = {2026},
  url = {https://dev-earth.interactiveatlas.org/eras/phanerozoic},
  note = {Accessed August 29, 2026}
}

The current eon, and the only one with an abundant fossil record: its name means visible life. It holds the Paleozoic, Mesozoic and Cenozoic eras, the whole span most people mean by geologic time.

Facts

Rank

Eon 1

Start (Million Years Ago)

538.8 1

The current eon, spanning about 11.8 percent of Earth's history per the cited article; it has no end date because it is still running.

End (Million Years Ago)

0 2

The Phanerozoic is the current, ongoing eon; 0 Mya marks the present day, the standard geologic timescale convention for an open upper boundary.

Key Event

The Cambrian explosion of complex, shelled, hard-bodied life, and every fossil-visible era since. 1

Cross-Tradition Connections