|(Personne absente de la base de donnée)|
Thèmes de Recherche :
My research addresses petrological problems by applying the latest techniques in geochemical analysis of rocks and constituent minerals, and integrating this information with petrologic data. I am particularly interested in obtaining new geochemical perspectives on the origin of magmas from the wide variety of magmatic settings found across western North America, both modern and ancient, and their tectonic implications. For my postdoctoral research at LMV, I am conducting isotopic and geochronologic analyses of magmatic rocks from the Northern Cascade Arc, located in Canada and the USA. The terminations of arcs, like the Northern Cascades, tend to be associated with magmas that are compositionally distinct from typical arc magmas. My work addresses how and why magma generation at arc terminations differs from traditional models for subduction zone magmatism. I am conducting Re-Os isotopic measurements, the first from the Northern Cascades, to determine the relative roles of the mantle, subducting slab, and continental crust in controlling variations in magma compositions. I am also measuring zircon U-Pb ages, primarily of plutonic granitoids in the Cascade arc, by LA-ICP-MS to obtain better constraints on how magma productivity and geochemistry has fluctuated through time as the arc has matured over its ~40 million year history. My project is part of the larger-scale study “The End of an Arc” that is supported by the Région Auvergne, LMV, University of British Columbia, and Simon Fraser University.
Themes of Research:
Isotopic analysis of magmatic rocks, minerals, and glasses by MC-ICP-MS and TIMS
U-Pb zircon geochronology by LA-ICP-MS
Integrating geochemical and petrologic data
Petrogenesis of subduction zone magmas, and relationships with tectonic and thermal regime
Tracking mantle geochemistry and mineralogy across western North America
Origin of temporal and spatial patterns in arc magma geochemistry
Responsabilités scientifiques et administratives :
Activités d’enseignement :
Mullen, E. K., Weis, D. (2015) Evidence for trench-parallel mantle flow in the northern Cascade Arc from basalt geochemistry. Earth and Planetary Science Letters 414, 100-107.
Mullen, E. K. and McCallum, I. S. (2014) Origin of basalts in a hot subduction setting: petrologic and geochemical insights from Mt. Baker, northern Cascade arc. Journal of Petrology 55, 241-281.
Mullen, E. K., and Weis, D. (2013) Sr-Nd-Hf-Pb isotope and trace element evidence for the origin of alkalic basalts in the Garibaldi Belt, northern Cascade arc. Geochemistry Geophysics Geosystems 14, 3126–3155, doi:10.1002/ggge.20191.
Mullen, E. K., and McCallum, I. S. (2013) Coexisting pseudobrookite, ilmenite, and titano-magnetite in hornblende andesite of the Coleman Pinnacle flow, Mt. Baker, Washing-ton: Evidence for a highly oxidized arc magma. American Mineralogist 98, 417-425.
McCallum, I. S., Schwartz, J. M., Mullen, E. K., Domeneghetti, M. C., Zema, M., Camara, F., McCammon, C., and Ganguly, J. (2006) Cooling history of lunar Mg-suite gabbronorite 76255, troctolite 76535 and Stillwater pyroxenite SC-936: The record in exsolution and ordering in pyroxenes. Geochimica et Cosmochimica Acta (Haskin special volume), 70(24), 6068-6078.
Rang A :
- Mullen E., Paquette J.L., Tepper J.H., McCallum I.S. (2018). Temporal and spatial evolution of Northern Cascade Arc magmatism revealed by LA–ICP–MS U–Pb zircon dating. Canadian Journal of Earth Sciences vol.55, p.443-462, DOI:10.1139/cjes-2017-0167 .
Rang B et C :
- Mullen E., Gannoun A.M., Nauret F., Schiano P., Weis D. (2015). Re-Os Isotopes Distinguish Crust vs. Slab Inputs to Northern Cascade Arc Basalts. AGU Fall Meeting 201, Abstract# V31A-3000,.