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Vol. 10 (2007 year), No. 1

Gordienko V.V., Gordienko Vl.Vl., Kalinicheva G.I., Olkhovaya E.A., Rumayntseva E.V., Timokhina L.A., Guberman D.M., Smirnov Yu.P., Yakovleva A.K., Yakovlev Yu.N.
Granitic pegmatite of the Kola Superdeep Borehole (vertical mineral-geochemical zoning and genesis problems)

The basement of the Early Proterozoic Pechenga palaeorift was penetrated by the Kola Superdeep Borehole (SG-3) at a depth of 6842-12262 m. In contrast to similar rocks framing the Pechenga palaeorift, Archaean rocks of SG-3 were affected by Proterozoic magmatism and metasomatism related to the rift development. The most intense Proterozoic processes were an intrusion of numerous mafic-ultramafic bodies, retrograde metamorphism and synmetamorphic migmatization, and emplacement of postkinematic granites. Most Proterozoic processes were determined to have been related to mantle sources. The overall amounts of Proterozoic material introduced into the Archaean rocks penetrated by the lowermost part of SG-3 coupled with the remobilized material of the Archaean crust is estimated at ?30 % (?12-15 % amphibolites, ~3 % granite veins, ~15 % migmatized rocks). Thus, searching for homologues to the SG-3 Archaean rocks does not lie only in a quest of analogous rocks in the frame of the Pechenga structure, but in the interpretation of the Proterozoic processes that have changed quantitative ratios and composition of the palaeorift basement rocks.

(in Russian, стр.14, fig. 3, tables. 7, ref 11, Adobe PDF, Adobe PDF 0 Kb)