Melts, fluids, crystals: Equilibrium and disequilibrium processes in magmatic systems and ore deposits

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This research programme investigates processes involving volatiles and their interactions with crystals and melts in magmatic systems. I, together with students and colleagues, will investigate volatile exsolution from melts to form bubbles, develop new ways to estimate volatiles in ancient magmas and degassed into the atmosphere, explore the role of minor volatiles in volcanic eruptions, quantify the ability of volatiles to transport Cl, S and ore metals at magmatic conditions and explore their influence on the delayed nucleation of crystals in magmatic systems. This research program is centred around experimental measurements and computer simulations, and involves collaboration with colleagues working in the field. ******More specifically, the goals of this research program for the next five years are to:***1. Quantify the partitioning of sulfur and halogens between melts and aqueous fluids in experiments to measure the solubility of the minor volatiles and their effects on the ability of hydrous fluids to transport critical ore metals (e.g., Pt, Sc, Li, rare earth elements, etc.). ***2. Measure the partitioning of minor volatiles (sulfur and halogens) between experimentally produced silicate melts and nominally volatile-free minerals (e.g., feldspar, clinopyroxene, olivine) in order to constrain pre-eruption magmatic volatile concentrations. The experimental results will be combined with measurements on natural minerals to estimate the volatile release from ancient flood basalts and those results provided to atmospheric scientists for modelling the effects of flood basalts on the terrestrial environment.***3. Investigate the role of minor volatiles on the exsolution (nucleation and growth) of bubbles from melts and their role in the initiation of volcanic eruptions through laboratory experiments and X-ray microtomographic studies. These measurements will be combined with computer models to determine the effects of different bubble size distributions on the permeabilities and strengths of magmatic foams.******4. Determine the role volatiles play in the supersaturation of magmatic melts with respect to crystallization of ore-rich minerals (e.g., sulfide, spodumene, iron oxides) and the formation of pegmatites through experimental studies of crystal nucleation and growth.******This research program will provide us with an improved picture of how volatiles behave and the role they play in magmatic systems. In five years we will better understand volatiles in magmas and will have advanced our abilities to model the evolution of magmas, the magmatic degassing of pre-historic eruptions, the formation of magmatic ore deposits, and the eruption of volcanoes.**