Constraining core composition is key to understanding planetary accretion, core-mantle differentiation, inner-core crystallization, and the evolution of geomagnetic fields. A broad range of siderophile elements may contribute to the chemical evolution of planetary cores. Core composition is governed by coupled seismological, mineral-physical, and geochemical constraints. Thermochemical equilibrium, as well as energy and mass exchange across the core-mantle and inner-core boundaries, further influence the distribution of elements in the liquid outer core and, where present, the solid inner core. Yet significant uncertainties remain because of the complex chemical behavior of core materials over the wide range of extreme conditions spanning the Martian core to Earth’s core.

We invite multidisciplinary studies of Earth’s and Martian core compositions, including experimental and theoretical mineral physics under extreme conditions, seismology, geodynamic modeling, and related approaches that advance understanding of core composition, structure, and evolution.

• DI - Study of the Earth's Deep Interior
• P - Planetary Sciences