Isotopic-geochronological studies of zircons from the Early Precambrian rocks of the southeastern Aldan-Stanovoy shield: New results and their geological interpretation

摘要

The results of the U-Pb (SHRIMP-II secondary ion microprobe) study of zircons from the metamorphic, ultrametagenic, and metamorphosed plutonic rocks of the southeastern Aldan-Stanovoy shield are reported and their geological interpretation is given. The obtained dates represent mainly the timing of the rock transformation at the different stages of prograde and retrograde metamorphism, ultrametamorphism, magmatism, and tectonic dislocations, rather than the age of the rock formation. The age values were united into nine generalized groups corresponding to definite geological events, which, in turn, are correlated with tectonic and petrological events in the western parts of the Stanovoy granite-greenstone and Aldan granulite-gneiss domains.