Modeling method for obtaining kinetic parameters of metamorphic reactions in texture-homogeneous rocks

Abstract

A new approach for deriving kinetic parameters of diffusion-controlled metamorphic reactions is described. It is based on comparison of models of temperature field evolution near a cylindrical intrusion and observable chemical changes in minerals at the contact aureole of the Kharlovo massif. The calculations yielded estimates of the effective rates of metamorphic reactions (~10-12 s-1) and the effective diffusion coefficient (5.29 10-16 cm2s-1 at T = 475 С). These values are consistent with experimentally and theoretically derived estimates of solid-state diffusion, including grain-boundary diffusion in mineral aggregates and segregations for the respective PT-parameters.