Природа эволюции магматизма в истории Земли

Abstract

Numerous evidences of hot heterogeneous accretion of the Earth have been obtained. According to these data, the Early Precambrian crystalline complexes and acidic crust were resulted from emerging residual melts formed by low-pressure compression fractionation of the bottom parts of the early magmatic ocean. The rise of residual melts from various layers of the magmatic ocean, crystallized from top to bottom, caused the evolution of magmatism of ancient platforms from acidic to basic, then to alkaline-ultrabasic and kimberlite. The warming of the mantle by the initially hot core led to the appearance of a direct geothermal gradient in it at the end of the Neoproterozoic and to the beginning of the rise of mantle plumes. Under their influence, oceanic and subduction environments were formed. Magmas in them are formed as a result of frictional and decompression melting of the differentiates of the magmatic ocean.