The Effect of the Disintegration of Chemical Stratification on the Time-dependent Behavior of the Earth’s Mantle

A. Galsa, and M. Herein
Eötvös University
Budapest, Hungary

Based on recent results from seismology, geochemistry etc. the distinct chemical character of the D’’ layer (lowest part of the mantle around the Earth’s core) has appeared unequivocally. Numerical calculations have been carried out to investigate the effect of the disintegration, mixing and homogenization of the dense D’’ on the time-dependent behavior of mantle convection.

A reinterpretation of the buoyancy parameter, which is the ratio of the stabilizing chemical density contrast and the destabilizing thermal density contrast, has been offered to highlight the existence of three separable processes being able to decrease the hindering effect of the dense D’’ layer on the mantle convection.