My major research interest is the role of volatiles (H2O, CO2, S, Cl, F) in magmatic and volcanic processes. More specifically, I am interested in integrating field studies of volcanic deposits, analytical data on pre-eruptive volatile abundances, and thermodynamic and physical modeling in order to understand the effects of volatiles on melting, crystallization, degassing, and eruption of magma. Thus my research covers a spectrum of topics from mantle geochemistry to physical volcanology. My major area of focus during the last five years has been magmatism associated with subduction zones, particularly those in which the subducting oceanic plate is relatively young and therefore at higher temperature than in many arcs around the world. The main scientific problem related to subduction of young plates is that they should dehydrate at shallow depths, while the plate is still beneath the forearc, thus reducing the influx of H2O and other recycled volatiles into the magma generation zone within the mantle wedge. The main goal of my research program has been to precisely measure the volatile contents of the different types of mafic magma in arcs to test ideas about how volatiles are recycled and how the recycling affects magma generation in arcs associated with young slabs. To this end, my graduate students and I have been studying the volatile contents of mafic arc magmas in both the Trans-Mexican Volcanic Belt (TMVB) and the Oregon and Northern California Cascades through the analysis of olivine-hosted melt inclusions. Another aspect of our studies has been to investigate crystallization, degassing and eruption process at cinder cone volcanoes. My group has also been using high-pressure experimental petrology to understand the conditions of magma formation in the mantle beneath arcs.
Melt inclusion preparation area Thermo-Nicolet Nexus 670 FTIR spectrometer
Petrographic microscope and polishing wheel