Planetary Science Seminar spring-2017

Title: The core-mantle boundary heat flux: measurements of mineral thermal conductivity at high pressures and temperatures

The heat flow in the deep interior of Earth has important implications for the thermal evolution of the core and mantle, including the age of the the solid inner-core and the mechanism powering Earth’s magnetic field. The thermal conductivity of the mineral assemblage present at the core-mantle boundary (CMB) exerts first order control on the heat flux from the core into the mantle. In order to arrive at geophysically relevant bounds on the bulk thermal conductivity of the CMB, pressure, temperature, compositional, and phase dependence of thermal conductivity is needed. Recent measurements of thermal conductivity of (Mg,Fe)O, by our group and another group, indicate thermal conductivity for this mineral is at the lower end of previous extrapolations to CMB conditions. The geophysical implications of these results are discussed.