Multicomponent exchange and diffusion in silicates

doi:10.1016/0016-7037(79)90158-3

Geochimica et Cosmochimica Acta

Volume 43, Issue 4, April 1979, Pages 455-469

https://doi.org/10.1016/0016-7037(79)90158-3 Get rights and content

Abstract

The treatment of multicomponent diffusion and exchange in silicates is developed. An ionic diffusion model, similar to one proposed by workers in ceramics, is described and applied to the evaluation of diffusion coefficients, D_ij, from tracer diffusion values. The general problem of cation exchange between complex silicates is then solved exactly, with particular emphasis on

1.
(a) useful approximations to the exact solutions;
2.
(b) the influence of the kinetic and thermodynamic parameters on the diffusion process; and
3.
(c) the limiting cases, which enable the complex silicates to be treated as binary systems, for the purposes of computing diffusion profiles.

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Citation Excerpt :
We first consider the dynamics of point defects, using atomic vacancies as an example. For simplicity, we assume a material with only one type of atoms for this discussion, but see e.g., Lasaga (1979), Poirier (1985, Section 2.2.3), and Kohlstedt and Hansen (2015) for how concentration and dynamics of vacancies in minerals are affected by the fact that the crystal is comprised of ions with electrical charges and must preserve electroneutrality. At thermodynamic equilibrium, there is a finite concentration of vacancies in a crystal (Ranalli, 1995, Section 9.3).
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Multicomponent exchange and diffusion in silicates

Abstract

Physica

Modeling of diffusion controlled properties of silicates

Progressive homogenization of metamorphic garnets, South Morar, Scotland: evidence for volume diffusion

Can. Mineralogist

Defects in ionic crystals

Dynamical Theory of Crystals Lattices

Reference frames and diffusion coefficients

Am. J. Sci.

Fe-Mg lattice diffusion in olivine

J. Geophys. Res.

Model for multi-component diffusion

Phys. Chem. Glasses

Vector space treatment of multicomponent diffusion

Diffusion, mobility and their interrelation through free energy in binary metallic systems

Trans. AIME

Non-Equilibrium Thermodynamics

Non-equilibrium thermodynamics as a model for diffusion-controlled metamorphic processes

Am. J. Sci.

Non-equilibrium thermodynamics in metamorphism

Studies in diffusion—III. Oxygen in feldspars; an ion microprobe determination

Geochim. Cosmochim. Acta