Geodynamic Nature of the Metamorphic Zonality of Northwestern Taimyr: Results of Numerical Modeling and Geological–Petrological Data

Zonal metamorphism is widely manifested within the North Taimyr tectonic zone; it is composed mainly of rocks from the continental slope and the foot of the Kara continent passive margin. To explain the features of the observed zonal metamorphism, we have carried out numerical geodynamic modeling, which reproduces the continental collision of the Kara and Siberian continents in the Late Paleozoic. It is shown that the modeled dynamics of P–T conditions of continental crust rocks (P–T–t trends) corresponds well to the thermodynamic parameters of the observed metamorphic zonality. A geodynamic scheme has been proposed, according to which the metamorphic zonality in northwestern Taimyr was formed on the descending branch of the P–T–t metamorphism trend. This metamorphism occurred at the final stage of collision, which formed the North Taimyr tectonic zone.