Emily Mullen

Emily Mullen
Postdoctoral Fellow
University of British Columbia

Since 2011, I have been a postdoctoral researcher at the University of British Columbia studying basalts at Salal Glacier, Bridge River, Mt. Meager, and Mt. Garibaldi, volcanic centers that comprise the northernmost Cascade arc. I have determined subducting sediment inputs and mantle heterogeneity beneath these volcanoes using high precision Sr, Nd, Hf and Pb isotope ratios and trace element abundances measured in the basalts. Before arriving at UBC, I completed my PhD at the University of Washington where I studied the origins of lavas at the Mt. Baker volcano using petrology, mineralogy and geochemistry. I was also involved in research on the thermal history of the Moon and a terrestrial analog, the Stillwater Complex layered mafic intrusion in Montana, measuring and modeling pyroxene compositional profiles.

Now as a postdoc with MAGNET, I am beginning a new research project that adds an economic geology perspective to my interests in igneous petrology and geochemistry. Some of the world’s most significant reserves of platinum group elements (PGE) occur in layered mafic intrusions, where PGE are concentrated in sulphide-rich layers. The origin of these zones remains controversial; their formation could be related to influxes of new magma into partly crystalline magma chambers, or to upward percolation of volatile-rich fluids. Because pulses of new magma can be detected by identifying changes in radiogenic isotope ratios, I am making high-precision measurements of Sr, Nd, Pb and Hf isotope ratios in a detailed transect across the ore-bearing zone (the J-M Reef) in the Stillwater Complex, the Western Hemisphere’s largest known source of palladium.