Exact treatment of moderately refractory-element loss during pebble accretion

Develop an exact treatment of the potential minor loss of silicon, magnesium, and chromium, or of additional accretion of ultra-refractory material, during pebble accretion in models of Earth’s formation.

Background

The Earth accretion model does not explicitly model possible depletion of the moderately refractory elements silicon, magnesium, and chromium during the early stage of pebble accretion, before a protective SiO-dominated vapor atmosphere forms above the magma ocean. The paper notes that such depletion could instead reflect the accretion of ultra-refractory material, such as calcium–aluminium-rich inclusions. Because the inferred planetesimal contribution and the fitted depletion parameters depend partly on these elements, a more physically complete treatment remains unresolved and is identified for future work.