High-gradient metamorphism and anatexis in the Teletsk-Chulyshman metamorphic belt (Gornyi Altai): New data on the age and estimate of P-T parameters.

Estimates of the P- T parameters of metamorphism, the first results of U-Pb dating of zircons from migmatites of the Teletsk-Chulyshman metamorphic belt, are reported. The age of migmatites from the southern block of the Teletsk-Chulyshman belt is 483.9 ± 5.7 Ma. As is evident from the pressure estimate (≤3-4 kbar), the Chulyshman migmatite-gneiss complex could be an apical part of the thermal-dome structure formed during the Early Ordovician thermal impact of a shallow magmatic basic thermal source, later displaced to the appropriate depth along the thrust at the collisional stage. [ABSTRACT FROM AUTHOR]