A model for the evolution size and composition of olivine crystals

Abstract

In this proceeding, a material model to describe the evolution of olivine crystals, in particular iron‐based Fayalite crystals, which are affected by the diffusion of magnesium ions, is introduced. These crystals are present in magma and understanding their behavior is an important aspect in improving prediction tools for volcanic eruptions. The model describes the development of the dislocation density, the concentration of magnesium over location and time, as well as the development of the size of the crystal over time. We discuss the model and the corresponding parameters. Furthermore, we present a numerical implementation of the model employing the platform Julia as well as a study on the influence of the various model parameters on the results. The results show a clear threshold between stable and unstable crystals.