The Rise and Fall of the Lower Mantle: Modelling Thermal Conductivity in Earth's Interior
Dr Stephen Stackhouse (SEE), Dr Andrew Walker, Dr Jon MoundContact email: email@example.com
The Earth’s lower mantle is convecting, with cold slabs subducting and hot plumes rising. Surface expressions of this large-scale convection include earthquakes, volcanism, oceanic trenches, mid-ocean ridges and island arc chains. The key role of heat transport means that thermal conductivity is a fundamental parameter in controlling mantle processes. In addition, as the thermal conductivity of the mantle mediates heat-loss from the core, it will also have significant implications for the thermoevolution of the Earth and magnetic field generation. To date, almost all studies of the thermal conductivity of the lower mantle have focused on the pure magnesium end-members of major mantle phases (i.e. MgSiO3 bridgmanite and MgO periclase), which comprise the bulk of the mantle. However, most interesting processes in the mantle (e.g. subduction and mantle upwelling), involve regions that are expected to differ in composition from the bulk (e.g. subducting slabs, large low shear velocity provinces (LLSVP) and ultra-low velocity zones (ULVZs)). The aim of this project is to determine the thermal conductivity of these regions, by performing atomistic simulations. The results will provide constraints on three important mantle processes (subduction of slabs, plume generation) and be integrated with previous results to construct a complete model of the thermal conductivity of the mantle, for use in mantle dynamics models.
Related undergraduate subjects:
- Earth science
- Geophysical science
- Physical science