Cambrian Period: Quick Facts

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Cambrian paleogeography

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.

Cambrian paleogeography

Illustration of Anomalocaris canadensis, a soft-bodied Cambrian predator, showing its elongated segmented body, large frontal appendages, circular mouth, and prominent eyes, with a simplified top view inset.

A chart showing the Cambrian period within the Paleozoic era on the geologic time scale, listing its epochs, stages, and corresponding ages in millions of years ago, with color-coded divisions and notes on boundary definitions.

trilobite fossil

Geochronology. Table 5: Subdivisions of the Cambrian System.

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Topics

Obolus Agnostus Cambrian Series 2 Epoch holmiid Margaretia dorus fossil Cambrian explosion archaeocyathid Paleozoic Era Silurian Period Devonian Period Ordovician Period Permian Period Carboniferous Period

Key People

Adam Sedgwick, engraving, 1875

Adam Sedgwick

British geologist