气候变化领域集成服务门户(CCPortal): Early accretion of planetesimals unraveled by the thermal evolution of the parent bodies of magmatic iron meteorites

CCPortal

DOI	10.1016/j.epsl.2020.116469
	Early accretion of planetesimals unraveled by the thermal evolution of the parent bodies of magmatic iron meteorites
	Kaminski E.; Limare A.; Kenda B.; Chaussidon M.
发表日期	2020
ISSN	0012821X
卷号	548
英文摘要	The timing of formation of 100-300 km size planetesimals in the protoplanetary disk remains largely unconstrained. Recent models show that gravitational collapse of boulders in overdense regions of a dusty accretion disk can overcome the meter-sized barrier and lead to rapid formation of planetesimals with size of several km that further grow by pebble accretion. Hf/W ages indicate that the first large planetesimals to form could be the parent bodies of magmatic iron meteorites. These ages have been so far used to constrain timing of accretion considering (i) instantaneous accretion, and (ii) purely conductive heat transfer in the planetesimal. To relax these hypotheses we model the thermal evolution of a planetesimal in course of accretion and we take into account the possibility of convection onset. Our model is further based on considering the possibility of a common thermal evolution for all the parent bodies of iron meteorites. Within that framework we show that the planetesimals could have grown following a universal accretion law starting at the very beginning of the history of the disk by a nearly instantaneous formation of 60 ± 30 km size nuclei, followed by a growth via pebble accretion at a much slower pace to reach final sizes of 150–300 km in about 3 Myr. In this universal scenario, complete melting and total differentiation are not bound to happen in the parent body due to the continuous accretion of cold pebbles. The model, though calibrated here on iron meteorites, is general and can in principle be applied to other types of planetesimals such as for instance the parent bodies of CV chondrites. © 2020 Elsevier B.V.
关键词	accretion analog experiments convection magmatic iron meteorites planetesimals
英文关键词	Heat transfer; Iron; Accretion disks; Conductive heat transfer; Convection onsets; Gravitational collapse; Iron meteorites; Parent bodies; Protoplanetary disks; Thermal evolution; Meteorites; accretion; chondrite; iron meteorite; parent body; planetesimal; thermal evolution
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/202690
作者单位	Université de Paris, Institut de Physique du Globe de Paris, CNRS, 1 rue Jussieu, Paris, F-75005, France
推荐引用方式 GB/T 7714	Kaminski E.,Limare A.,Kenda B.,et al. Early accretion of planetesimals unraveled by the thermal evolution of the parent bodies of magmatic iron meteorites[J],2020,548.
APA	Kaminski E.,Limare A.,Kenda B.,&Chaussidon M..(2020).Early accretion of planetesimals unraveled by the thermal evolution of the parent bodies of magmatic iron meteorites.Earth and Planetary Science Letters,548.
MLA	Kaminski E.,et al."Early accretion of planetesimals unraveled by the thermal evolution of the parent bodies of magmatic iron meteorites".Earth and Planetary Science Letters 548(2020).