RB-SR SYSTEMS IN THE ROCKS OF CENTRAL PAM IR - THE INFLUENCE OF ALPINE METAMORPHISM

The behavior of Rb-Sr systems under the conditions of amphibolitic fac ies alpine metamorphism has been studied in Early Paleozoic granites a nd Phanerozoic primary-sedimentary rocks of inner zones of Djalansky a nd Shatputsky domes of East Famir anticlinorium. The range of Rb and/o r Sr migration in granites is high enough to destroy the Rb-Sr systems in 1.5-2 kg rock samples whereas approximately 10 kg samples remained ''closed''. In the primary-sedimentary rocks remarkable reformation o f Rb-Sr systems occurred 20 Ma ago with Sr isotope composition equilib rating within separate sections. The data obtained show that the amphi bolite facies rocks were altered only by alpine progressive regional m etamorphism within die East Pamir anticlinorium.