Planetary differentiation

It is still controversial when and how the core segregation and silicate differentiation have occurred on differentiated planets including the Earth. One way to solve this problem is to analyze siderophile elements in extraterrestrial materials such as iron meteorites and achondrites. As a related issue, it is important to understand the origin of metal phases in the early solar system. To this end, we investigete the abundances and isotopic compositions of Os and Fe in metal phases in chondrites.

Related papers

Okabayashi, S., Yokoyama, T., Nakanishi, N., Iwamori, H.

Fractionation of highly siderophile elements in metal grains from unequilibrated ordinary chondrites: Implication for the origin of chondritic metals.
Geochemica et Cosmochemica Acta, 244, 197-215, 2019.

Nakanishi, N., Yokoyama, T., Okabayashi, S., Usui, T. and Iwamori, H.

Re-Os isotopic systematics and fractionation of siderophile elements in metal phases from CBa chondrites.
Meteoritics and Planetary Science, 53, 1051-1065, 2018.

Yokoyama, T., Walker, D. and Walker, R.J.

Low osmium solubility in silicate at high pressures and temperatures.
Earth and Planetary Science Letters, 279, 165-173, 2009.