AGE LIMITS AND FORMATION DURATION OF PALEOPROTEROZOIC VOLCANIC BELTS IN THE CENTRAL ALDAN SHIELD

Abstract

The available geological, geochronological, geochemical, and isotopic data furnish evidence that the Paleoproterozoic protoliths of metavolcanic rocks in the central Aldan Shield were formed within a geodynamic system of the active continental margin of the Olekma–Aldan microplate and the Fedorovka island arc as a result of the deposition of volcanosedimentary rocks in the Balaganakh greenstone belt (active continental margin) along with the formation of the Fedorovka volcanic sequence and the protoliths of the associated orthogneisses of the Timpton Complex. The evolution of this system was completed by the collision of the Fedorovka island arc and the Olekma–Aldan continental microplate and the development of the deep-seated thrust faults of the Chuga and Fedorovka systems ~1992 Ma ago.