The Full Wiki

Pannotia: Wikis

Advertisements
  
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Did you know ...


More interesting facts on Pannotia

Include this on your site/blog:

Encyclopedia

From Wikipedia, the free encyclopedia

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.[1]

Contents

Formation

About 750 million years ago (750 Ma), the previous supercontinent Rodinia rifted apart into three continents: Proto-Laurasia (which broke apart and eventually re-formed as Laurasia), the continental craton of Congo, and Proto-Gondwana (all of Gondwana except the Congo craton and Atlantica).

Proto-Laurasia rotated southward toward the South Pole. Proto-Gondwana rotated counterclockwise. The Congo craton came between Proto-Gondwana and Proto-Laurasia 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.[2]

Geography and lifespan

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

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.[3]

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.

See also

External links

References

  1. ^ "Pannotia". Palaeos. http://www.palaeos.com/Earth/Geography/Pannotia.html. Retrieved 2006-03-12.  
  2. ^ "Precambrian Paleobiology". Virtual Fossil Museum. http://www.fossilmuseum.net/Geological_History/PreambrianGelogicalHistory.htm. Retrieved 2006-03-12.  
  3. ^ "Pannotia". UCMP Glossary. http://evolution.berkeley.edu/glossary_entry/glossary.php?word=Pannotia. Retrieved 2006-03-12.  
Advertisements

Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message