Project Summary This is a one-year NSF EaGER proposal for collaborative research between mineral physicists and seismologists at the University of Minnesota, University of California Santa Cruz, and Arizona State University. A multidisciplinary foundation has been laid in recent decades and there is an opportunity to be seized by combining mineral physics and seismology explicitly and interactively in analyses of new perspectives of the deep Earth. Advances in seismic imaging of the Earth's deep interior, from global to local scales, are providing structural information about convective and thermal patterns in the lower mantle. Development of first principles methodologies to tackle key mineral physics problems, e.g., thermoelastic properties, spin crossover in iron in lower mantle minerals, and anharmonic thermal properties, are greatly expanding characterization of mineral properties at deep mantle conditions. The goal and primary intellectual merit of the proposed work is to advance understanding of deep mantle structure, temperature, and composition: this is a grand challenge of foremost importance in Earth Sciences. We propose to initiate a transformative multidisciplinary effort to directly link seismological imaging with modeling approaches based on realistic mineral properties. We will address an unresolved central issue in investigations of deep mantle temperature and composition: the subtle effects of spin state changes in iron in lower mantle minerals and potential seismological detection of this fundamental transition and corresponding implications for bulk chemistry of the lower mantle. Clarification of the seismic signature of spin state crossovers is a major hurdle to be overcome in mineralogical interpretations of seismological data of the deep Earth. The proposed search for spin transition signatures in the deep mantle is not without risks, but this unprecedented joint seismology/mineral-physics enterprise will pave the way for future studies of numerous fascinating structures holding keys to the nature of the deep mantle. It will open a needed first-hand dialogue between these communities. These will be major broader impacts. Critical elasticity data accessible online will be generated and made conveniently accessible to the seismology community. This will be a high impact activity on its own. Also, the close interaction between students of different backgrounds and PIs with diverse expertise will ignite the formation of a multi-disciplinary group of researchers with a lesser knowledge gradient between seismology and mineral physics.
|Effective start/end date||7/1/13 → 6/30/14|