气候变化领域集成服务门户(CCPortal): Early evolution of the solar accretion disk inferred from Cr-Ti-O isotopes in individual chondrules

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DOI	10.1016/j.epsl.2020.116585
	Early evolution of the solar accretion disk inferred from Cr-Ti-O isotopes in individual chondrules
	Schneider J.M.; Burkhardt C.; Marrocchi Y.; Brennecka G.A.; Kleine T.
发表日期	2020
ISSN	0012821X
卷号	551
英文摘要	Isotopic anomalies in chondrules hold important clues about the dynamics of mixing and transport processes in the solar accretion disk. The meaning of these anomalies is debated and they have been interpreted to indicate either disk-wide transport of chondrules or local heterogeneities of chondrule precursors. However, all previous studies relied on isotopic data for a single element (either Cr, Ti, or O), which does not allow distinguishing between source and precursor signatures as the cause of the chondrules' isotope anomalies. To overcome this problem, we obtained the first combined O, Ti, and Cr isotope data for individual chondrules from enstatite, ordinary, and carbonaceous chondrites. We find that chondrules from non-carbonaceous (NC) chondrites have relatively homogeneous Δ17O, ε50Ti, and ε54Cr, which are similar to the compositions of their host chondrites. By contrast, chondrules from carbonaceous chondrites (CC) have more variable compositions, some of which differ from the host chondrite compositions. Although the compositions of the analyzed CC and NC chondrules may overlap for either ε50Ti, ε54Cr, or Δ17O, in multi-isotope space, none of the CC chondrules plot in the compositional field of NC chondrites, and no NC chondrule plots within the field of CC chondrites. As such, our data reveal a fundamental isotopic difference between NC and CC chondrules, which is inconsistent with a disk-wide transport of chondrules across and between the NC and CC reservoirs. Instead, the isotopic variations among CC chondrules reflect local precursor heterogeneities, which most likely result from mixing between NC-like dust and a chemically diverse dust component that was isotopically similar to CAIs and AOAs. The same mixing processes, but on a larger, disk-wide scale, were likely responsible for establishing the distinct isotopic compositions of the NC and CC reservoirs, which represent in inner and outer disk, respectively. © 2020 The Author(s)
关键词	chondrules isotopic anomalies meteorite dichotomy nebular mixing
英文关键词	Dust; Isotopes; Meteorites; Mixing; Titanium compounds; Accretion disks; Carbonaceous chondrites; Isotope anomalies; Isotopic composition; Isotopic variations; Local heterogeneity; Mixing process; Transport process; Chromium compounds; accretion; chondrule; chromium; evolution; isotopic analysis; meteorite; oxygen isotope; titanium
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202880
作者单位	Institut für Planetologie, University of Münster, Wilhelm-Klemm-Straße 1048149, Germany; CRPG, CNRS, Université de Lorraine, UMR 7358, Vandoeuvre-lès-Nancy, 54501, France; Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
推荐引用方式 GB/T 7714	Schneider J.M.,Burkhardt C.,Marrocchi Y.,et al. Early evolution of the solar accretion disk inferred from Cr-Ti-O isotopes in individual chondrules[J],2020,551.
APA	Schneider J.M.,Burkhardt C.,Marrocchi Y.,Brennecka G.A.,&Kleine T..(2020).Early evolution of the solar accretion disk inferred from Cr-Ti-O isotopes in individual chondrules.Earth and Planetary Science Letters,551.
MLA	Schneider J.M.,et al."Early evolution of the solar accretion disk inferred from Cr-Ti-O isotopes in individual chondrules".Earth and Planetary Science Letters 551(2020).