Modified Jeffery model: Influence of particle concentration on mineral fabric in moderately concentrated suspensions

Abstract

A modified Jeffery model involving particle interactions allows the simulation of preferred orientation of crystals and the anisotropy of magnetic susceptibility in magmatic flow with up to 40% of rigid particle fraction. Numerical simulations are compared to analogue and natural fabrics. A study of the role of particle concentration shows that the increasing percentage of crystal fraction in dilute suspensions leads to progressive attenuation of the fabric intensity and cyclicity. At high strains in simple shear flow, the lineation converges to a constant value close to the shear plane. With increasing particle concentration, the fabric diverges from the shear direction reflecting the effect of increased crystal tiling. The model can be applied to quantify mineral preferred orientations of crystal mushes in magmatic fabric studies. Key Points A numerical model for semi-dilute suspensions in viscous flow Agreement with results of analogue modeling Applicable to study preferred orientation and AMS in magmatic rocks ©2013. American Geophysical Union. All Rights Reserved.