Hierarchy classification:

1. top of the aat hierarchies
2. Styles and Periods Facet
3. Styles and Periods (hierarchy name)
4. [styles, periods, and cultures by general era]
5. geologic time scale

Narrower term/s

• Proterozoic
• Archean

Anotations

Scope note:

Period of the geologic time scale that extends from about 4.6 billion years ago, from the Earth's formation, to the beginning of the Cambrian Period, 542 million years ago. The Precambrian represents more than 80 percent of the total geologic record, and contains the earliest evidence for the advent of life; microfossils that resemble algae, cysts of flagellates, tubes interpreted to be the remains of filamentous organisms, and mounded colonies of photosynthetic bacteria called stromatolites.