Volatile element evolution of chondrules through time
|Author(s)||Mahan Brandon1, Moynier Frederic1, 2, Siebert Julien1, 2, Gueguen Bleuenn3, 4, 5, Agranier Arnaud3, 4, Pringle Emily A.1, 6, Bollard Jean7, Connelly James N.7, Bizzarro Martin1, 7|
|Affiliation(s)||1 : Univ Paris Diderot, Sorbonne Paris Cite, CNRS UMR 7154, Inst Phys Globe Paris, F-75238 Paris 05, France.
2 : Inst Univ France, F-75005 Paris, France.
3 : Univ Bretagne Occidentale, UMR CNRS 6538, Lab Geosci Ocean, F-29280 Plouzane, France.
4 : Inst Univ Europeen Mer, F-29280 Plouzane, France.
5 : Inst Univ Europeen Mer, UMS CNRS 3113, F-29280 Plouzane, France.
6 : Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA.
7 : Univ Copenhagen, Ctr Star & Planet Format, DK-1350 Copenhagen, Denmark.
|Source||Proceedings Of The National Academy Of Sciences Of The United States Of America (0027-8424) (Natl Acad Sciences), 2018-08 , Vol. 115 , N. 34 , P. 8547-8552|
|WOS© Times Cited||9|
|Keyword(s)||cosmochemistry, planetary formation, pebble accretion, Solar System evolution, meteorites|
Chondrites and their main components, chondrules, are our guides into the evolution of the Solar System. Investigating the history of chondrules, including their volatile element history and the prevailing conditions of their formation, has implications not only for the understanding of chondrule formation and evolution but for that of larger bodies such as the terrestrial planets. Here we have determined the bulk chemical composition-rare earth, refractory, main group, and volatile element contents-of a suite of chondrules previously dated using the Pb-Pb system. The volatile element contents of chondrules increase with time from similar to 1 My after Solar System formation, likely the result of mixing with a volatile-enriched component during chondrule recycling. Variations in the Mn/Na ratios signify changes in redox conditions over time, suggestive of decoupled oxygen and volatile element fugacities, and indicating a decrease in oxygen fugacity and a relative increase in the fugacities of in-fluxing volatiles with time. Within the context of terrestrial planet formation via pebble accretion, these observations corroborate the early formation of Mars under relatively oxidizing conditions and the protracted growth of Earth under more reducing conditions, and further suggest that water and volatile elements in the inner Solar System may not have arrived pairwise.