The supra-dome part of the Birkhinsky granite gneiss dome composed of gabbro and gabbro-diorites encompasses numerous linear zones of granitization. The supply of granitizing components through tectonic zones caused metasomatic transformation of gabbro into plagiogranite or granite, and (relatively to gabbro) the supply was SiO_2 23 percent, Na_2O 1.2 percent, K_2O 2.3 percent, so as, respectively, removal made TiO_2 0.8 percent, Al_2O_3 1.2 percent, SIGMA Fe 7 percent, MnO 0.1 percent, MgO 5.3 percent, CaO 8.1 percent, P_2O_5 0.25 percent. In the same row, there is, when comparing the 《gabbro-granite》 extremes, a distinct supply of Rb 80 ppm, Ba 310 ppm and removal of Y - 14 ppm, Co - 20 ppm, Ni - 80 ppm, Sc - 25 ppm, V - 190 ppm, Cr - 190 ppm. At the final stages of granitization process the mature metasomatites were melted with a subsequent formation of granite dykes and pegmatites. The age of pegmatites was dated to be 5.30 Ma after zircons.
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