Presented by Lars Stixrude – University College London
Melt was almost certainly more widespread in the past and the entire Earth may once have been molten, with profound consequences for our planet’s evolution and current processes. Very little is known experimentally of the nature of silicate melts throughout most of the mantle’s pressure-temperature regime. We have explored these materials with first principles molecular dynamics simulations based on density functional theory. This state of the art method, widely used across the material sciences, is ideally suited to predicting the physical properties and phase relations of melts throughout Earth’s mantle. We discuss the implications of our recent findings for the presence of a two-layered magma ocean, the sequence of crystallization and the vector of chemical differentiation, the earliest thermal evolution of Earth, the earliest atmosphere, reaction between magma ocean and core, and the possibility of an early silicate dynamo.