当前位置: X-MOL 学术Nature › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Hadean isotopic fractionation of xenon retained in deep silicates
Nature ( IF 50.5 ) Pub Date : 2022-06-22 , DOI: 10.1038/s41586-022-04710-4
Igor Rzeplinski 1 , Chrystèle Sanloup 1 , Eric Gilabert 2 , Denis Horlait 2
Affiliation  

Our understanding of atmosphere formation essentially relies on noble gases and their isotopes, with xenon (Xe) being a key tracer of the early planetary stages. A long-standing issue, however, is the origin of atmospheric depletion in Xe1 and its light isotopes for the Earth2 and Mars3. Here we report that feldspar and olivine samples confined at high pressures and high temperature with diluted Xe and krypton (Kr) in air or nitrogen are enriched in heavy Xe isotopes by +0.8 to +2.3‰ per amu, and strongly enriched in Xe over Kr. The upper +2.3‰ per amu value is a minimum because quantitative trapping of unreacted Xe, either in bubbles or adsorbed on the samples, is likely. In light of these results, we propose a scenario solving the missing Xe problem that involves multiple magma ocean stage events at the proto-planetary stage, combined with atmospheric loss. Each of these events results in trapping of Xe at depth and preferential retention of its heavy isotopes. In the case of the Earth, the heavy Xe fraction was later added to the secondary CI chondritic atmosphere through continental erosion and/or recycling of a Hadean felsic crust.



中文翻译:

深部硅酸盐中氙的 Hadean 同位素分馏

我们对大气形成的理解主要依赖于惰性气体及其同位素,氙(Xe)是早期行星阶段的关键示踪剂。然而,一个长期存在的问题是大气中 Xe 1的消耗及其地球2和火星3的轻同位素的起源。在这里,我们报告了在高压和高温下限制在空气或氮气中稀释的 Xe 和氪 (Kr) 的长石和橄榄石样品中的重 Xe 同位素每amu富集了 +0.8 至 +2.3‰ ,并且在 Kr 上强烈富集了 Xe . 每亩上+2.3‰值是最小值,因为可能会定量捕获未反应的 Xe,无论是在气泡中还是吸附在样品上。鉴于这些结果,我们提出了一个解决 Xe 缺失问题的方案,该问题涉及原行星阶段的多个岩浆海洋阶段事件,以及大气损失。这些事件中的每一个都会导致 Xe 在深度处被捕获并优先保留其重同位素。在地球的情况下,后来通过大陆侵蚀和/或哈迪斯长英质地壳的再循环,将重 Xe 部分添加到次生 CI 球粒陨石大气中。

更新日期:2022-06-23
down
wechat
bug