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. In Geology, a supercontinent is a Landmass comprising more than one Continental core or Craton. The Pan-African orogeny was a series of major Neoproterozoic orogenic events (mountain building which related to the formation of the Supercontinents The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current It is also known as the Vendian supercontinent. [1]
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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). Annum is one form of the Latin noun meaning Year, not a form normally used for derivatives in modern languages the accusative singular For the Genus of Metalmark butterflies, see Rodinia (butterfly. In Geology, a rift is a place where the Earth 's crust and Lithosphere are being pulled apart and is an example of Extensional tectonics Laurasia (lɔˈreɪʃiə lɔˈreɪʒə was a Supercontinent that most recently existed as a part of the split of the Pangaean supercontinent in the late Mesozoic A continent is one of several large Landmasses on Earth. They are generally identified by Convention rather than any strict criteria with seven regions A craton ( Greek kratos / κρἀτος ( neut. "strength" is an old and stable part of the Continental crust that has survived The Congo craton, covered by the Palaeozoic -to-recent Congo basin, is an ancient Precambrian Craton that with four others (the Kaapvaal Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Atlantica was an ancient Continent theorised to have formed about two billion years ago
Proto-Laurasia rotated southward toward the South Pole. The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is the southernmost point on the surface of the Earth. Proto-Gondwana rotated counterclockwise. The Congo craton came between Proto-Gondwana and Proto-Laurasia about 600 Ma. A craton ( Greek kratos / κρἀτος ( neut. "strength" is an old and stable part of the Continental crust that has survived 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. The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other [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. For the Genus of Metalmark butterflies, see Rodinia (butterfly. Panthalassa ( Greek, meaning 'all seas' also known as the Panthalassic Ocean, was the vast global Ocean that surrounded the Supercontinent The Pacific Ocean is the largest of the Earth 's Oceanic divisions There was a mid-ocean ridge in the middle of the Panthalassic Ocean. A mid-ocean ridge or mid-oceanic ridge is an underwater Mountain range typically having a valley known as a Rift running along its axis formed by 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. The Pan-African Ocean is an hypothesized paleo-ocean that surrounded the Supercontinent of Pannotia.
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. Laurentia (also known as the North American craton) like all Craton land was created as continents moved about the surface of the Earth Baltica redirects here For the Russian beer, see Baltika Breweries Baltica is a name applied by geologists to a late- Proterozoic, Siberia is the Craton located in the heart of the region of Siberia. Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Later, altered landmasses would recombine to form the most recent supercontinent, Pangaea. Pangaea, Pangæa or Pangea (pænˈdʒiːə from παν pan, meaning entire, and Γαῖα Gaea, meaning Earth in [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. The Neoproterozoic Era is the unit of geologic time from 1000 to 542 +/- 0 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
- An image showing Pannotia according to Christopher Scotese. Plate tectonics (from Greek τέκτων tektōn "builder" or "mason" describes the large scale motions of Earth 's Lithosphere The supercontinent cycle describes the quasi-periodic aggregration and dispersal of Earth 's Continental crust. Christopher Scotese is geologist at the University of Texas at Arlington. (it is referred to as the late Precambrian Supercontinent in the image). The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current
References
- ^ Pannotia. Palaeos. Retrieved on 2006-03-12. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 538 - Witiges, king of the Ostrogoths ends his siege of Rome and retreats to Ravenna, leaving
- ^ Precambrian Paleobiology. Virtual Fossil Museum. Retrieved on 2006-03-12. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 538 - Witiges, king of the Ostrogoths ends his siege of Rome and retreats to Ravenna, leaving
- ^ Pannotia. UCMP Glossary. Retrieved on 2006-03-12. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 538 - Witiges, king of the Ostrogoths ends his siege of Rome and retreats to Ravenna, leaving
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