PECULIARITIES OF THE EARLY PRECAMBRIAN METAMORPHISM IN EASTERN AND WESTERN PARTS OF THE BELOMORSKY FOLDED BELT (BALTIC SHIELD)

摘要

Analysis of the evolution of metamorphism within Belomorsky folded belt has shown that events of the same age differed in its Western and Eastern parts in conditions of their realisation. So, during all the stages of development, metamorphism in the Eastern zone was characterized by the lower gradient regime in comparison with the Western part. This should be connected with heterogeneity of geotectonic situation, which was far more intensive in Later Archean in the eastern area due to forming of thrust nappe structures there. But later, contrast between regime of metamorphism in eastern and western parts of the belt decreased with time.