Thermal Structure from Models of Mantle Convection with Surface Plates, Temperature-dependent and Radially Stratified Viscosity

------Cold downwellings--------------Hot upwellings--------

This animation shows the evolution of thermal structure within the mantle over a period of about 4 transit times (equivalent to ~200 Ma). The scale of thermal structure is controlled by surface plates. Downwelling sheets and upwellings plumes are the predominant structures. Thermal anomalies below spreading centers only extend to a depth of about 200 km.

Model parameters: internal heating=61%; activation energy=9.21; Rayleigh number=2.6x10^6; LM_Viscosity/UM_Viscosity=60; plate rheology;