气候变化领域集成服务门户(CCPortal): Lunar compositional asymmetry explained by mantle overturn following the South Pole-Aitken impact

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DOI	10.1038/s41561-021-00872-4
	Lunar compositional asymmetry explained by mantle overturn following the South Pole-Aitken impact
	Zhang, Nan; Ding, Min; Zhu, Meng-Hua; Li, Huacheng; Li, Haoyuan; Yue, Zongyu
发表日期	2022
ISSN	1752-0894
EISSN	1752-0908
起始页码	37
结束页码	+
卷号	15 期号:1 页码:13
英文摘要	The spatial distribution of mare basalts, titanium and KREEP (potassium, rare earth elements and phosphorus) on the Moon is asymmetrical between the nearside and farside. These asymmetries cannot be readily explained by solidification of a global magma ocean and subsequent mantle overturn, which should result in a layered and spherically symmetric lunar interior. Alternative scenarios have been proposed to explain the observed compositional asymmetry, but its origin remains enigmatic. Here, we present hydro- and mantle convection numerical simulations of the giant impact event that formed the South Pole-Aitken basin-the largest impact basin on the Moon-and the subsequent impact-induced convection with the assistance of gravitational instability. We find that the impact induces thermochemical instabilities that drive the dense KREEP-rich ilmenite-bearing cumulate to migrate towards the nearside following lunar magma ocean solidification. This results in the formation of a chemical reservoir under the nearside crust that could explain the observed geochemical asymmetries. We suggest that enrichments of ilmenite and KREEP in the nearside hemisphere following the South Pole-Aitken impact event provide a viable explanation for the wide composition range of mare basalts observed on the lunar surface. The compositional asymmetry between the Moon's near- and farsides can be explained as the result of impact-induced mantle convection and gravitational instability, according to numerical modelling of the South Pole-Aitken impact and the ensuing mantle evolution.
学科领域	Geosciences, Multidisciplinary
语种	英语
WOS研究方向	Geology
WOS记录号	WOS:000741303600001
来源期刊	NATURE GEOSCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/272598
作者单位	Peking University; Curtin University; Macau University of Science & Technology; Chinese Academy of Sciences
推荐引用方式 GB/T 7714	Zhang, Nan,Ding, Min,Zhu, Meng-Hua,et al. Lunar compositional asymmetry explained by mantle overturn following the South Pole-Aitken impact[J],2022,15(1):13.
APA	Zhang, Nan,Ding, Min,Zhu, Meng-Hua,Li, Huacheng,Li, Haoyuan,&Yue, Zongyu.(2022).Lunar compositional asymmetry explained by mantle overturn following the South Pole-Aitken impact.NATURE GEOSCIENCE,15(1),13.
MLA	Zhang, Nan,et al."Lunar compositional asymmetry explained by mantle overturn following the South Pole-Aitken impact".NATURE GEOSCIENCE 15.1(2022):13.