Pannotia

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Pannotia, first described by Ian W. D. Dalziel in 1997, is a hypothetical supercontinent that existed from the Pan-African orogeny about 600 million years ago to the end of the Precambrian about 540 million years ago. It is also known as the Vendian supercontinent.<ref name="palaeos">Pannotia. Palaeos. Retrieved on 2006-03-12.</ref>

1 Formation
2 Movements
3 A short lived supercontinent
4 See also
5 External link
6 References

[edit] Formation

About 750 Ma, the previous supercontinent Rodinia rifted apart into three continents:

Protolaurasia (Protolaurasia broke apart and eventually reformed as Laurasia)
The continental craton of Congo
Proto-Gondwana (all of Gondwana except the Congo craton and Atlantica)

[edit] Movements

Protolaurasia rotated southward toward the south pole. Protogondwana rotated counterclockwise. The Congo craton came between Protogondwana and Protolaurasia about 600 Ma. This formed Pannotia. With so much landmass around the poles, evidence suggests that there were more glaciers during this time than at any other time in geologic history.<ref>Precambrian Paleobiology. Virtual Fossil Museum. Retrieved on 2006-03-12.</ref>

[edit] A short lived supercontinent

Pannotia was short-lived. The collisions that formed Pannotia were glancing collisions, and the continents composing Pannotia already had active rifting. By about 540 Ma, or only about 60 million years after Pannotia formed, Pannotia disintegrated into four continents: Laurentia, Baltica, Siberia and Gondwana. Later, altered landmasses would recombine to form the most recent supercontinent, Pangaea.<ref>Pannotia. UCMP Glossary. Retrieved on 2006-03-12.</ref>

Another term for the supercontinent that is thought to have existed at the end of Neoproterozoic time is "Greater Gondwanaland", suggested by Stern in 1994. This term recognizes that the supercontinent of Gondwana, which formed at the end of the Neoproterozoic, was once part of the much larger end-Neoproterozoic supercontinent.

Pannotia looked like a "V" that faces the northeast direction. Inside the "V" was an ocean that opened up during the break-up of Rodinia, Panthalassic Ocean, an ocean that will become mostly the Pacific Ocean. There is a mid-ocean ridge in the middle of the Panthalassic Ocean. Outside of the "V" was a very large, ancient ocean called Panafrican Ocean that may have surrounded Pannotia, equivalent to the future Panthalassic Ocean.