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DOI	10.1038/s41561-021-00870-6
	Earth’s missing argon paradox resolved by recycling of oceanic crust
	Tucker J.M.; van Keken P.E.; Ballentine C.J.
发表日期	2022
ISSN	1752-0894
卷号	15 期号:1
英文摘要	The extent to which primordial mantle domains have survived billions of years of convective mixing is a fundamental question in mantle dynamics and geochemistry. The observation that around half of Earth’s 40Ar is missing from the atmosphere has been used to argue for a largely primordial, convectively isolated lower mantle. This hypothesis is apparently supported by lower 40Ar/36Ar ratios in the mantle source of ocean-island basalts compared with mid-ocean-ridge basalts. However, strongly layered convection is contradicted by seismic tomographic observations and geodynamic constraints. Using joint geodynamic–geochemical modelling of mantle convection, we show that high 40Ar concentrations associated with K-rich subducted oceanic crust plus unmelted material dispersed throughout the mantle can fully account for Earth’s 40Ar budget. This solution to the missing Ar paradox requires neither a substantial reduction in Earth’s assumed K concentration nor large isolated domains in the mantle. We additionally show that subducted atmosphere-derived Ar has little effect on the mantle 40Ar budget but can substantially reduce mantle 40Ar/36Ar ratios. Unlike He and Ne isotope systems, whose variations reflect primarily incorporation of primordial material, mantle 40Ar/36Ar ratios may instead result from subduction of atmosphere-derived Ar into the deep mantle. © 2022, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.
语种	英语
scopus关键词	argon; crustal recycling; mantle convection; mantle source; mid-ocean ridge basalt; mixing; oceanic crust; subduction
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/250803
作者单位	Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, United States; Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, DC, United States; Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
推荐引用方式 GB/T 7714	Tucker J.M.,van Keken P.E.,Ballentine C.J.. Earth’s missing argon paradox resolved by recycling of oceanic crust[J],2022,15(1).
APA	Tucker J.M.,van Keken P.E.,&Ballentine C.J..(2022).Earth’s missing argon paradox resolved by recycling of oceanic crust.Nature Geoscience,15(1).
MLA	Tucker J.M.,et al."Earth’s missing argon paradox resolved by recycling of oceanic crust".Nature Geoscience 15.1(2022).