Origin of the depletion of siderophile volatile elements in Earth, Mars and the aubrite parent body

• Applicant: Professor Dr. Harry Becker
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 242130583

New data on the composition and evolution of the terrestrial planets suggest that the heterogeneous accretion model currently favored for Earth, accretion of reduced, volatile poor material followed by oxidized, volatile rich material, may not be generally applicable. Mars, and possibly also Mercury, have similar or higher abundances of moderately volatile elements than Earth, and may have accreted before accretion of Earth was completed. To complicate matters, abundances of highly volatile elements in Earth may be higher than in Mars. The role of late accretion of undifferentiated material after core formation (late veneer) for the volatile element budget of the terrestrial planets remains unclear. Abundances of highly siderophile elements indicate that Earth, Moon, Mars and parent bodies of some differentiated meteorites all have been affected by a late veneer. Here, new concentration data of siderophile volatile elements (S, Se, Te, Cd, Tl, Cu, Ag, In, Pb) will be obtained to study the influence of core formation and the composition of the late veneer on abundances of volatile elements in the silicate earth, Mars, and in the aubrite parent body (a model for Mercury?). The data will be used with data for other volatile elements and experimental studies to obtain new insights into the distribution of volatile elements in the terrestrial planets.

• DFG Programme: Research Grants