Solidification of Earth's mantle led inevitably to a basal magma ocean.

ABSTRACT: One of the main interpretations of deep-rooted geophysical structures in the mantle¹ is that they stem from the top-down solidification of the primitive basal magma ocean of Earth above the core^2-6. However, it remains debated whether solids first formed at the bottom of the mantle, solidifying upward, or above the melts, solidifying downward. Here we show that gravitational segregation of dense, iron-rich melts from lighter, iron-poor solids drives mantle evolution, regardless of where melting curves and geotherms intersect. This process results in the accumulation of iron-oxide-rich melts above the core, forming a basal magma ocean. We numerically model mantle solidification using a new multiphase fluid dynamics approach that integrates melting phase relations and g

SUBMITTER: Boukare CE 

PROVIDER: S-EPMC11964929 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature