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

Resumo

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.