OLDEST (3.5 GA) ZIRCONS OF THE URALS: U-PB (SHRIMP-II) AND T DM CONSTRAINTS

Abstract

The Archean domains of the Earth composed of granite–greenstone and granulite–gneiss associations are now sufficiently well studied. Nevertheless, many aspects related to the early history of the planet are still far from being solved [1, 2, and others]. Such a situation is also characteristic of the Uralian foldbelt. The formation of the crust in this region spanned a long period comprising the Archean–Early Proterozoic, Late Proterozoic, Paleozoic, and post-Paleozoic stages. In recent years, considerable progress has been achieved in reconstruction of the major features of the last three stages in the foldbelt evolution mainly due to the active introduction of advanced methods of isotope geology based on sophisticated analytical equipment into geological studies.