Atomic Diffusion and Mantle Mixing

Materials are continuously cycled through Earth’s interior by plate tectonics and mantle convection, and mixed in the process. The survival of distinct chemical zones depends on diffusion, both through its control on viscosity, which influences the scale of physical mixing, and on the rate of chemical exchange between stretched and thinned regions. This talk will review recent experimental and theoretical constraints on rates of atomic diffusion in the deep mantle, and their implications for mantle mixing.