Kelly Russell

My interests are in volcanology and igneous petrology as related to the formation, transport and eruption of magma.  My group is pursuing 3 main themes.

A) Glaciovolcanism - Land-based Paleo-environment Proxy: This research seeks to understand glaciovolcanic processes better, to reconstruct Pleistocene-aged Cordilleran icesheets (CIS) through space & time, and to test and refine models for causal linkages between volcanism and glacial loading and unloading of the lithosphere. Mapping glaciovolcanic edifices and their deposits, combined with geochronometry, informs on the spatial-temporal distribution(s) and thicknesses of paleo-ice-sheets, and terrestrial paleo-environments. The proposed work will provide critical datasets for mapping the presence (and absence) of Cordilleran ice sheets in space & time, reconstructing ice-sheet dynamics over the past 2-3 Ma, and for guiding numerical models that explore potential linkages between volcanism in the BC cordillera and glaciations. Principles established here can be applied to other regions of the planet, and to other planets (e.g. Mars).

B) A Model for Planetary Melt Viscosity: The viscosity of silicate melts is the most important property governing volcanic and magmatic processes. Accurate prediction of viscosity across the range of temperatures, compositions, and pressures found in Nature remains a seminal challenge - notwithstanding our fundamental, highly cited "GRD model" (N>1600). My goal is to produce a more robust and comprehensive 2nd generation 
model that better serves an increasing diversity of users (e.g. planetary & material sciences). The new model will: i) be more accurate relative to the experimental database, ii) span a wider range of compositions (e.g., kimberlite), and iii) include pressure, CO2, and iron redox. The final model will capture natural silicate (and silica-carbonate) melts and predict related melt properties (e.g., activation energy, etc).

C) Transport & Eruption of Mantle Xenoliths: Mantle xenoliths serve as the only direct window into Earth's mantle. Their common occurrence in volcanic deposits indicates successful entrainment and transport by low- viscosity melts through great thicknesses of orogenic (>50-80 km) or cratonic (>200 km) lithosphere. Their size (up to 1 m) and density dictate that, relative to the magma, they continuously settle (i.e. sink) during transport. A simplistic Stokes Law approach for xenolith settling requires aphysical magma ascent rates, posing the question: "how does this mantle cargo make it to the Earth's surface?" This collaboration (with Lancaster U.) comprises: i) field-study of mantle xenoliths to collect abundances (No.'s/m3), size distributions, shape/surface properties, ii) geothermometry to establish "relative" source depths, and iii) fluid-analogue experiments to explore how dense particles settle or rise in complex (non-Arrhenian) viscous fluids. Results will establish regime diagrams for flow in dykes that map conditions for successful vs. failed transport of mantle cargo.

Research Tools & Results:

Web-based VISCOSITY CALCULATOR:  GRD VISCOSITY MODEL

Glaciovolcanic Constrained CIS Dynamics in SW British Columbia: Model_Movie