气候变化领域集成服务门户(CCPortal): Early volatile depletion on planetesimals inferred from C–S systematics of iron meteorite parent bodies

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DOI	10.1073/pnas.2026779118
	Early volatile depletion on planetesimals inferred from C–S systematics of iron meteorite parent bodies
	Hirschmann M.M.; Bergin E.A.; Blake G.A.; Ciesla F.J.; Li J.
发表日期	2021
ISSN	00278424
卷号	118 期号:13
英文摘要	During the formation of terrestrial planets, volatile loss may occur through nebular processing, planetesimal differentiation, and planetary accretion. We investigate iron meteorites as an archive of volatile loss during planetesimal processing. The carbon contents of the parent bodies of magmatic iron meteorites are reconstructed by thermodynamic modeling. Calculated solid/molten alloy partitioning of C increases greatly with liquid S concentration, and inferred parent body C concentrations range from 0.0004 to 0.11 wt%. Parent bodies fall into two compositional clusters characterized by cores with medium and low C/S. Both of these require significant planetesimal degassing, as metamorphic devolatilization on chondrite-like precursors is insufficient to account for their C depletions. Planetesimal core formation models, ranging from closed-system extraction to degassing of a wholly molten body, show that significant open-system silicate melting and volatile loss are required to match medium and low C/S parent body core compositions. Greater depletion in C relative to S is the hallmark of silicate degassing, indicating that parent body core compositions record processes that affect composite silicate/iron planetesimals. Degassing of bare cores stripped of their silicate mantles would deplete S with negligible C loss and could not account for inferred parent body core compositions. Devolatilization during small-body differentiation is thus a key process in shaping the volatile inventory of terrestrial planets derived from planetesimals and planetary embryos. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Carbon; Iron meteorites; Planetary accretion; Planetesimals; Sulfur
语种	英语
scopus关键词	carbon; iron; silicate; sulfur; Article; astronomy; carbon partitioning; chemical composition; depletion; iron meteorite; melting point; planetesimal; priority journal; thermodynamics; volatilization
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180097
作者单位	Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN 55455, United States; Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, United States; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, United States; Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Chicago Center for Cosmochemistry, University of Chicago, Chicago, IL 60637, United States; Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109, United States
推荐引用方式 GB/T 7714	Hirschmann M.M.,Bergin E.A.,Blake G.A.,等. Early volatile depletion on planetesimals inferred from C–S systematics of iron meteorite parent bodies[J],2021,118(13).
APA	Hirschmann M.M.,Bergin E.A.,Blake G.A.,Ciesla F.J.,&Li J..(2021).Early volatile depletion on planetesimals inferred from C–S systematics of iron meteorite parent bodies.Proceedings of the National Academy of Sciences of the United States of America,118(13).
MLA	Hirschmann M.M.,et al."Early volatile depletion on planetesimals inferred from C–S systematics of iron meteorite parent bodies".Proceedings of the National Academy of Sciences of the United States of America 118.13(2021).