|From the desk of Bruce Wilkinson:
|"Our own Rob Moucha (along with colleagues P. Glisovic and A.M. Forte at the University of Quebec at Montreal) have authored a super paper entitled: “Time-dependent convection models of mantle thermal structure constrained by seismic tomography and geodynamics: implications for mantle plume dynamics and CMB heat flux” that recently appeared Geophysical Journal International. The gist of the paper is that “good” thermal convection models should be consistent with flow dynamics, and be capable of providing an evolution of mantle thermal structure that is as Earth-like as possible. Rob and colleagues constructed a time-dependent, compressible convection model with spherical geometry that is consistent with tomography-based flow dynamics.
The neat feature of their solutions is that the equations of conservation of mass and momentum are solved only once. This facilitates the modeling of depth-dependent thermal conductivity profiles, extreme variations of viscosity over depth, and different surface boundary conditions. Their billion-year-scale simulations will allow them to determine the extent to which a ‘memory’ of the starting tomography-based thermal structure is preserved and, as everyone might guess, to explore the longevity of the structures in the present-day mantle. They further demonstrate that model mantle upwellings are stable features, mainly owing to the geodynamically-inferred high viscosity in the lower mantle."