A NEW MANTLE CONVECTION MODEL CONSTRAINED BY SEISMIC TOMOGRAPHY DATA

We assume that the heterogeneity in the Earth's mantle is caused by the thermal convection in it. First, we transform the seismic tomography data of the mantle into the density (or temperature) anomaly and take it as the driving force of the mantle convection. Then we take account of the three basic equations, which control the mantle convection system, to investigate the patterns of the mantle flow. We use the seismic tomograpy model SH12WM13 to calculate the mantle convection patterns with different Rayleigh numbers up to 10 6. Results show that the mantle convection patterns depend on not only the seismic tomography data, but also the Rayleigh numbers very much. When the Rayleigh number is higher, the convection pattern is more complex. Particularly, there is regional layer convection and multiple scales convection in the modeled mantle. If this result is to be approved, it will change greatly our knowledge about the structure of the mantle thermal dynamical processes.