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arXiv 1208.2909astro-ph.EP
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行星的化学分化:一个核心问题

Chemical differentiation of planets: a core issue

Herve Toulhoat, Viacheslav Zgonnik

摘要:

通过绘制地球上相对于太阳的经验化学元素丰度,并归一化为硅与其第一电离势,我们证实了先前报道的相关性的存在。为了解释这一点,我们开发了一个模型的基础上的统计物理学原理,预测分化相对丰度的任何行星体在太阳系作为其轨道距离的函数。这个简单的模型是成功地测试对现有的化学成分数据CI陨石和火星,地球,月球,金星和水星的表面成分数据。此外,我们表明,偏离拟议的法律为一个给定的行星对应于后来的表面分离的元素驱动的重力和化学反应。因此,我们为太阳系和行星内部的元素分布提供了一幅新的图景,并对它们的化学组成产生了重要影响。特别是,4wt%的初始氢含量预测散装早期地球。这与其他研究结果一致,表明地球内部可能富含氢。

英文摘要:

By plotting empirical chemical element abundances on Earth relative to the Sun and normalized to silicon versus their first ionization potentials, we confirm the existence of a correlation reported earlier. To explain this, we develop a model based on principles of statistical physics that predicts differentiated relative abundances for any planetary body in a solar system as a function of its orbital distance. This simple model is successfully tested against available chemical composition data from CI chondrites and surface compositional data of Mars, Earth, the Moon, Venus, and Mercury. We show, moreover, that deviations from the proposed law for a given planet correspond to later surface segregation of elements driven both by gravity and chemical reactions. We thus provide a new picture for the distribution of elements in the solar system and inside planets, with important consequences for their chemical composition. Particularly, a 4 wt% initial hydrogen content is predicted for bulk early Earth. This converges with other works suggesting that the interior of the Earth could be enriched with hydrogen.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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