Читать книгу Isotopic Constraints on Earth System Processes - Группа авторов - Страница 55

There are two classes of diffusion models that can explain complicated diffusion behavior in a multicomponent system. The first is a more general multicomponent diffusion model that invokes a matrix of diffusion coefficients (Onsager, 1945). The second is a form of effective binary diffusion model in which components diffuse in response to activity gradients, which in turn are given by the concentration of SiO₂ (Richter, 1993; Zhang, 1993).