Main stages of tectonomagmatic activity of the Tuva-Mongolian microcontinent in the Precambrian: data on the U-Pb age of zircons

摘要

The U-Pb age of zircons from Ediacaran sandstones of the cover of the Tuva-Mongolian microcontinent and the rocks of its Early Precambrian basement (Gargan block) was analyzed by the LA-ICP-MS method. The major stages of tectonomagmatic activity of this block include the Neoarchean, Paleoproterozoic (no younger than 2 Ga), and Neoproterozoic. Comparison of the age of zircons from Ediacaran terrigenous rocks of the Tuva-Mongolian microcontinent and sandstones of the reference sections of the Ediacaran shelf of the Siberian platform undeniably indicates their independent accumulation.