Multifield Governing Equations For Magma Dynamics

A general set of conservation equations for mass, chemical species, momentum, and energy is proposed as a framework for magma dynamics studies. These equations are based on a multifield approach and can in principle describe the entire range of macroscopic dynamics ranging from melt extraction in the mantle to magma chamber dynamics to ascent and eruption, fully accounting for mechanical and thermodynamic non-equilibrium between phases. Multiple crystal/bubble compositions and sizes, which define populations, are accounted for by tracking each population as a separate field. The equations are intended to serve as a basis for development of large-scale, “global” numerical simulation approaches to magmatic systems, and as a framework for laboratory and computational models of specific aspects of magmatic systems. Use of the equations to guide experimental studies and as a basis for large-scale numerical simulation of magmatic processes are briefly discussed.