Summary: | dTwenty-three new Ar-40/Ar-39 amphibole age determinations have been carried out to date major crustal boundaries in the sediment-covered crystalline basement of the western part of the East European Craton, in the area between the Baltic (Fennoscandian) and the Ukrainian Shields. That crystalline basement is characterised by a pronounced alternation of granulite-and amphibolite -facies rock belts identified from geophysical surveys and deep drill core samples. These belts strike NNE to NW and are considered to represent accretionary stacking of different Palaeoproterozoic (2.0-1.85 Ga) terranes of juvenile crust along the margins of the Archaean protocontinents of Fennoscandia, Sarmatia and Volgo-Uralia, which make up the cores of the EEC.
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