Current geophysical models of the Earth's mantle and core are based mostly on estimated properties of mantle and core minerals. This study is to obtain properties of several mantle and core minerals by experiment simultaneously at high pressures and temperatures. An important physical property of the deep Earth, the pressure-volume-temperature equation of state, can be determined for candidate mantle minerals by the experiments. The results will be used to address problems of the composition of the Transition Zone, the lower mantle, and the core-mantle boundary. The PIs will measure with high accuracy the thermal expansion and bulk modulus of mantle minerals at high pressures and temperatures in the System Fe-Mg-CA-A1-Si-O.2. They are among the leading practitioners of this important area of research. Funding at the revised level is recommended.
