Testing Mineralogical Models of the Mantle Transition Zone Using Seismic Data

Mantle composition plays an essential role in understanding evolution, mantle dynamics and phase transitions of the Earth's mantle. With increasing amounts of experimental data, chemical interactions of various phases can be explored between different subsystems, and seismic velocity and density profiles can be calculated based on compositional models. The ability to quantitatively calculate seismic profiles based on compositional models makes it possible for compositional models to be directly tested and constrained using seismic data. The investigators will perform a joint modeling of seismic and mineral physics data to constrain compositional and thermal models in the Earth's transition zone. The collaborative research also investigates regional variation of seismic structures, as well as its cause, using seismic data sampling various tectonic regions. The intellectual merits of the collaborative research include quantitative and integrative studies of seismic structures, wave propagation, mantle composition and mantle mineralogy in the Earth's transition zone. This research has broad impacts on training of a graduate student in both seismology and mineral physics, and providing seismically-constrained compositional and thermal models which would serve as a basis for a quantitative understanding of the effects of mantle mineralogy on the dynamics of the descending slabs and ascending mantle plumes, and for a quantitative link between seismic velocity perturbations, mantle temperature, and density buoyancy in large-scale geodynamical modeling.