My research addresses how magmatism and volcanism have shaped the evolution of the solid Earth. I'm especially interested in the rate and mechanism by which continental crust forms at subduction zones. This interest takes my research group to the Mexican Volcanic Arc, where we are documenting magma eruption rates, the proportions of different erupted magma types, and the role of water in creating the unique compositional character and stratification of continental crust. We additionally use thermodynamics to extract information about the temperature, pre-eruptive water contents, depth (pressure), and crystallization history of magmas. An example is our new model of the plagioclase-liquid hygrometer/thermometer. Finally, we are involved in measuring various thermodynamic properties of silicate and carbonate liquids; the goal is to use these data is to calculate crystal-melt equilibrium at any condition in the crust and mantle. We are using a new frequency-sweep acoustic interferometer to measure sound speeds in a wide variety of melt compositions in order to develop an improved equation of state (P-V-T relation) for magmatic liquids.