Three-dimensional numerical simulations of thermo-chemical multiphase convection in the Earth's mantle

Abstract

Three-dimensional numerical simulations of thermo-chemical mantle convection that include melting-induced compositional differentiation, self-consistent plate-like behavior, and composition-dependent solid-solid phase changes (including the newly-discovered post-perovskite transition) are used to model the 4.5 billion year evolution of the Earth, and are successful in matching many of the major observational constraints. These simulations are at high Rayleigh number (107) and large viscosity contrast (varying by six orders of magnitude with temperature and two orders of magnitude with depth), and can match many characteristics of Earth's mantle from a compositionally-homogeneous initial condition, with all chemical heterogeneity generated by melting-induced differentiation. Such simulations achieve greater realism than previously possible and facilitate an improved understanding of the dynamics of the Earth and planetary interiors. © 2005 Elsevier Ltd.