Metal differentiation on asteroids recorded in Zn and Fe isotopic signatures of ureilites

Autor(en)

S. M. Chernonozhkin, L. Pittarello, G. Hublet, S. Weyer, I. Horn, P. Claeys, V. Debaille, F. Vanhaecke, S. Goderis

Abstrakt

Ureilites are meteorites that represent mantle restites of a planetesimal likely disrupted before the magma ocean stage and then reaccreted. Historically, it was speculated that evaporation shifts the Zn isotope ratios in ureilites toward heavier compositions. The fact that the ureilite parent body (UPB) is depleted in some moderately volatile elements (MVEs) makes ureilites an appealing target to study isotopic fractionation by evaporation in the early Solar System. Here, we show that Fe and Zn isotope ratios of bulk ureilites and their metal and silicate components rather record metal melting and extraction of Fe-FeS melts in the UPB, which also resulted in isotopic disequilibrium between the silicate and metal parts. This finding underlines that the isotopic evolution of MVEs in the early Solar System is not only affected by evaporation, but also by planetary differentiation processes due to the chalcophile and/or siderophile behaviour of many MVEs. It shows that to avoid interpretational bias due to undersampling of planetesimal reservoirs in meteorite collections, and to distinguish planetary differentiation from evaporation, isotopic compositions of MVEs should be combined with common geochemical proxies.

Organisation(en)

Department für Lithosphärenforschung, Dekanat der Evangelisch-Theologischen Fakultät

Externe Organisation(en)

Ghent University , Montanuniversität Leoben, Geological Survey of Finland, Naturhistorisches Museum Wien – NHMW, Université Libre de Bruxelles, Institute of Earth System Sciences, Gottfried Wilhelm Leibniz Universität Hannover, Vrije Universiteit Brussel

Journal

Geochemical Perspectives Letters

Band

33

Seiten

38-43

Anzahl der Seiten

6

ISSN

2410-339X

DOI

https://doi.org/10.7185/geochemlet.2501

Publikationsdatum

2025

Peer-reviewed

Ja

ÖFOS 2012

105120 Petrologie, 105105 Geochemie

ASJC Scopus Sachgebiete

Environmental Chemistry, Geology, Geochemistry and Petrology

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/9029e8ba-7554-475a-94f5-b66fca7671f2