WHEN DID THE PLATE TECTONICS BEGIN? THE INCEPTION OF PLATE TECTONICS BASED ON THE EXISTENCE OF KOMATIITES AND THEIR MgO VARIATIONS

The geoscientists have always wondered what evolutionary processes the Early Earth went through until it reached today. The beginning of the plate tectonics poses another matter of debate in these processes. Yet, the debates on when the plate tectonics began have not been resolved. In this sense, especially the lack of records regarding the period of time before the Cambrian Era is considered the biggest obstacle against resolution of these debates. The geoscientists have befi tted from various methods to come up with different proposals about the beginning of the plate tectonics. The most notable rock type among the ones produced by the mantle is the komatiites. While the oldest datable komatiite is 3.82 Ga; the youngest is 0.086 Ga. With the high content of magnesium they contain, their special texture and the geological setting, the komatiites are not similar to any other rock groups which can currently be examined. Though they were produced in different geological times, no up to date forms of these rocks have been observed. Given the formation conditions of komatiites, recorded time intervals and the content of magnesium they contain, they might indicate when the plate tectonics began.

Keywords:

Crust, Plate Tectonic, Continental Crust Earth, Komatiite,

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ISSN: 0026-4563
Yayın Aralığı: Yılda 3 Sayı
Başlangıç: 1950
Yayıncı: Cahit DÖNMEZ

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