SPP 1833 - Subproject: Modelling of accretion and differentiation of the proto-Earth and its building blocks

Basic data for this project

Description

The proposed project will address the central questions regarding the thermal, structural and compositional (including volatiles) evolution of planetary embryos (building blocks of the Earth), the accretion of the proto-Earth prior to the series of giant impacts, as well as its differentiation. Chemical and physical processes influencing the melt segregation and differentiation into a layered structure will be studied resulting in a more comprehensive understanding of these processes. A model of a planetary embryo for bodies smaller than ~500 km in radius was developed previously by the applicant and will be expanded to further consider impact heating and heat transport by solid state convection - processes than become more relevant for bodies with increasing radius. Growth of such an embryo and its differentiation will be considered, resulting in a Mars-sized proto-Earth. A further important enhancement of the model is the determination of the melting and crystallisation products to obtain better constraints on the compositional layering of planetary embryos. Although we will focus on numerical modelling, sample-based geochemical-mineralogical data for extra-terrestrial materials (e.g. HEDs (howardite, eucrite, diogenite) and magmatic iron meteorites) as well as synthesis of mission results (e.g. the Dawn mission) will be used to guide and to test the models.