My research is motivated by fundamental questions of whole Earth evolution. A key geodynamic question is how large-scale mass transfer occurs between deep and shallow regions of the mantle. This question is important because the phenomena of mantle plume activity, continental rifting and plate convergence are intimately linked to the thermo-chemical structure of the deep Earth. Related questions are the extent to which the mantle preserves geochemically discrete reservoirs, and how chemical heterogeneities from the mantle are manifest in the compositions of mafic lavas. Research in East Africa, Turkey and Saudi Arabia explores the geochemical consequences of large- and small-scale lithospheric delamination associated with slab rollback and/or breakoff and lithospheric drip magmatism. Research throughout the East African Rift System evaluates models of continental break-up and the initiation of oceanic rift segmentation using structural and geochemical evidence. My work also includes study of the dynamics of volcanism and lithospheric modification in subduction environments. These volcanoes have the capacity for explosive activity that could prove fatal to millions of people, so characterizing magmatic processes and eruptive behavior is critical. My approach to these questions combines field work, geochemical analysis and microanalysis of mineral textures and compositions to determine thermal, chemical and physical properties of eruptive systems. My ultimate goal is to develop a robust model of lithospheric behavior that compares and contrasts the geochemical effects of disturbance in extensional and compressional tectonic environments.
Current research projects include:
- Origin of the Tungnáhraun in SE Iceland: Earth’s largest basalt lava flows
- Deciphering the lithospheric metasomatic history beneath the African Western Rift
- Genesis of Eocene Turkish lamprophyres associated with orogenic collapse
- Evolution of heterogeneous mantle source domains beneath Anatolia
- Geodynamics of NW Saudi Arabia: diffuse Red Sea rifting, Dead Sea Fault evolution, plume material transport and mafic volcanism in young Harrat basalts
- Understanding controls on U isotopes in reducing environments
- Determining the silicate weathering feedback strength during critical Earth history events
- Reconstructing the marine redox state and Earth system feedbacks around the Ediacaran-Cambrian Transition
I am a high-temperature geochemist and petrologist who uses major and trace element abundance data and radiogenic isotopic signatures (Sr-Nd-Pb-Hf-He-Os) of volcanic rocks to study the evolution of the asthenosphere and lithosphere over geologic time. Most of my work centers on the development of volcanic and plutonic bodies that form in extensional and plume-related environments in the East African Rift, Iceland and the circum-Mediterranean (Turkey, Saudi Arabia). I earned my Ph.D. from the Massachusetts Institute of Technology after completing a BSE in civil engineering from Princeton University and a Fulbright to the University of Iceland. Prior to coming to Penn State, I was an assistant professor in the Department of Environmental Sciences at the University of Virginia and was the founding director of the UVa Branch of the Virginia Museum of Natural History.