Age of Migmatites in the Stanovoi Complex, East Siberia: Results of Zircon Dating by the SHRIMP II U-Pb Method

摘要

The age of granite gneisses and migmatites, which belong to the Stanovoi Complex and occupy a considerable territory of the Dzhugdzhur-Stanovoi fold region (DSFR), remains a pressing issue because of the recently obtained new isotopic-geochronological evidence for the Mesozoic reactivation of this region, in particular, the manifestation of high-grade metamorphism and migmati-zation in the Early Cretaceous (140 Ma ago). However, data on the Neoarchean and Paleoproterozoic ages of high-grade metamorphic complexes are reported in. Datings of the protolith of the Stanovoi granite gneisses (～3 Ga), granitization (2706 Ma), and the retrograde Paleoproterozoic metamorphism (1915 Ma) were carried out for the El'gakan Block of the western DSFR.