A growing number of lines of evidence suggest that silicic magma bodies ? which give rise to hazardous explosive volcanic eruptions ? are characteristic and possibly restricted to shallow levels of the Earthh's crust. Why is this the case? What controls the depths from which eruptions emanate? Is it possible to generate and erupt silicic magma from deeper levels within the crust? How do magma properties, such as density and viscosity, interact with crustal properties, such as rigidity and elasticity, to ultimately control the eruption of magmas? These questions underlie the scientific motivation for this project that will address them by developing theoretical models derived from physical and chemical theory in order to predict the behavior of crustal magmas at the onset of volcanic eruption.
In this project, the collaborative team will build upon their ongoing effort to develop coupled thermodynamics and fluid dynamics models, and to apply these models to selected natural systems. In their previous work, they developed an improved model to perform thermodynamic calculations of phase relations for silicic magmas and laid the foundation for coupling thermodynamics and fluid dynamics models by applying them to several natural systems. With this with this Accomplishment-based renewal award, they will expand these thermodynamic models to include the effects of carbon dioxide and sulfur on the fluid phase, and fully couple them with new and existing fluid dynamics models of both magmas and country-rocks, permitting rigorous evaluation of the interplay between phase change, magma dynamics, and country-rock behavior. It is also planned used the coupled models to several silicic systems including the Bishop Tuff, Peach Spring Tuff, Oruanui Tuff and Cotopaxi Volcano.
