Precambrian
Pre-cambrian (or Precambrian) is a term used to describe the eons before the Cambrian. It lasted from about 4.567 billion years BC to about 542 million years BC. It starts with the beginning of the Earth, about 4.567 billion years BC.[1][2][3] When it ends, there were many hard-shelled animals around. It is named after the Roman name for Cymru / Wales, because rocks thought to be from this time were first studied there.
The supereon is subdivided into 3 eons, the Hadean (4.5 to 4 billion years BC), the Archaean (4 to 2.5 billion years BC) and the Proterozoic (from 2.5 billion years to 542 million years BC).[4]
The immediate Precambrian period is the Ediacaran.
Precambrian Media
- Temagami greenstone belt pillow lava.jpg
Weathered Precambrian pillow lava in the Temagami Greenstone Belt of the Canadian Shield
Map of Kenorland breaking up 2.3 billion years ago[source?]
- Paleoglobe NO 1590 mya-vector-colors.svg
The supercontinent Columbia about 1.6 billion years ago
- Positions of ancient continents, 550 million years ago.jpg
Landmass positions near the end of the Precambrian[source?]
References
- ↑ "Age of the Earth". U.S. Geological Survey. 1997. Retrieved 2010-08-06.
- ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
- ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
- ↑ Stanley, Steven M. 1999. Earth system history. New York: W.H. Freeman and Company. ISBN 0-7167-2882-6.
