What do pallasite meteorites tell us about processes deep in the interior of differentiated planet(essimal)s?

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Theoretical and numerical studies indicate that chemical heterogeneity in the outer core region profoundly influences the dynamics and evolution of Earth's core and mantle, and the behaviour of the geomagnetic field. However, we presently don't know much about this heterogeneity. For example, tantalizing hints of geochemical heterogeneity in the outermost core are given by anomalous seismic signals at the core-mantle boundary, but this region of our planet is by no means accessible for direct geochemical investigation (despite what movies such as "The Core" would have you believe). Atomistic modelling provides some constraints on what chemical composition could be expected in the deepest portions of the mantle and geophysical modelling techniques can be used to predict geochemical heterogeneity within the outermost core. Pallasite meteorites may be derived from differentiated planetesimals, subsequently smashed into fragments by collisions with large bolides early in the history of the solar system. These meteorites may provide indirect evidence with which processes deep within the Earth can be tested. This project will use a combination of geochemical investigations of pallasite meteorites, geophysical modelling of the composition of the Earth's outermost core and atomistic modelling of equilibrium metal / silicate compositions to investigate the nature and origin of pallasite meteorites and what information they contain regarding differentiation processes in planetary bodies.