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Pannotia (meaning "all southern land"), also known as Vendian supercontinent, Greater Gondwana, and the Pan-African supercontinent, was a relatively short-lived Neoproterozoic supercontinent that formed at the end of the Precambrian during the Pan-African orogeny (650–500 Ma) and broke apart 560 Ma with the opening of the Iapetus Ocean. Pannotia was named by Ian W. D. Dalziel in 1997. It split into the continents of Laurentia, Siberia and Baltica, with the main landmass, Gondwana, south of it. ==Formation== The formation of Pannotia began during the Pan-African orogeny when the Congo continent got caught between the northern and southern halves of the previous supercontinent Rodinia some 750 Ma. The peak in this mountain building event was around 640–610 Ma, but these continental collisions may have continued into the Early Cambrian some 530 Ma. The formation of Pannotia was the result of Rodinia turning itself inside out. Before Rodinia rifted apart it was composed of five elements: Laurentia or the Canadian Shield at the centre; North American west coast adjacent to the eastern margins of Antarctica and Australia (or East Gondwana); the Amazon Craton east of Laurentia; Baltica next to present-day Greeanland; and Siberia north of Baltica. Rodinia rifted apart into three larger 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pannotia」の詳細全文を読む スポンサード リンク
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