气候变化领域集成服务门户(CCPortal): A 4,565-My-old andesite from an extinct chondritic protoplanet

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DOI	10.1073/pnas.2026129118
	A 4,565-My-old andesite from an extinct chondritic protoplanet
	Barrat J.-A.; Chaussidon M.; Yamaguchi A.; Beck P.; Villeneuve J.; Byrne D.J.; Broadley M.W.; Marty B.
发表日期	2021
ISSN	00278424
卷号	118 期号:11
英文摘要	The age of iron meteorites implies that accretion of protoplanets began during the first millions of years of the solar system. Due to the heat generated by 26Al decay, many early protoplanets were fully differentiated with an igneous crust produced during the cooling of a magma ocean and the segregation at depth of a metallic core. The formation and nature of the primordial crust generated during the early stages of melting is poorly understood, due in part to the scarcity of available samples. The newly discovered meteorite Erg Chech 002 (EC 002) originates from one such primitive igneous crust and has an andesite bulk composition. It derives from the partial melting of a noncarbonaceous chondritic reservoir, with no depletion in alkalis relative to the Sun's photosphere and at a high degree of melting of around 25%. Moreover, EC 002 is, to date, the oldest known piece of an igneous crust with a 26Al-26Mg crystallization age of 4,565.0 million years (My). Partial melting took place at 1,220 °C up to several hundred kyr before, implying an accretion of the EC 002 parent body ca. 4,566 My ago. Protoplanets covered by andesitic crusts were probably frequent. However, no asteroid shares the spectral features of EC 002, indicating that almost all of these bodies have disappeared, either because they went on to form the building blocks of larger bodies or planets or were simply destroyed. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Andesitic magmatism; Differentiated meteorites; Early solar system; Planetary differentiation
语种	英语
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/180283
作者单位	Univ Brest, CNRS, IR4, Ifremer, LEMAR, Plouzané, F-29280, France; Institut de physique du globe de Paris, CNRS, Université de Paris, Paris, F-75005, France; National Institute of Polar Research, Tachikawa, Tokyo, 190-8518, Japan; CNRS, Institut de Planetologie et d'Astrophysique de Grenoble, Saint Martin d'Hères, F-38400, France; Université de Lorraine, CNRS, CRPG, Nancy, F-54000, France
推荐引用方式 GB/T 7714	Barrat J.-A.,Chaussidon M.,Yamaguchi A.,et al. A 4,565-My-old andesite from an extinct chondritic protoplanet[J],2021,118(11).
APA	Barrat J.-A..,Chaussidon M..,Yamaguchi A..,Beck P..,Villeneuve J..,...&Marty B..(2021).A 4,565-My-old andesite from an extinct chondritic protoplanet.Proceedings of the National Academy of Sciences of the United States of America,118(11).
MLA	Barrat J.-A.,et al."A 4,565-My-old andesite from an extinct chondritic protoplanet".Proceedings of the National Academy of Sciences of the United States of America 118.11(2021).