Nucleosynthetic isotope anomalies of zinc in meteorites constrain the origin of Earth's volatiles.
Nucleosynthetic isotope anomalies of zinc in meteorites constrain the origin of Earth's volatiles.
复制标题
陨石中锌的核合成同位素异常限制了地球挥发物的起源。
DOI：
10.1126/science.abn1021
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Martins R
中科院分区：
文献类型：
--
作者：
Martins R
从不同核合成来源继承的物质赋予陨石和类地行星不同的同位素特征。这些核合成同位素异常被用来限制形成地球的物质的起源。然而，只有高冷凝温度的元素才被发现异常，使得地球挥发性元素的起源不受约束。我们确定了18块陨石中的中等挥发性元素锌的同位素组成，并确定了核合成锌同位素异常。使用质量平衡模型，我们发现，碳质的机构，这可能形成超越木星的轨道，提供了约一半的地球锌库存。结合之前对其他元素的研究，这些结果表明地球质量的10%是由碳质物质提供的。
Material inherited from different nucleosynthesis sources imparts distinct isotopic signatures to meteorites and terrestrial planets. These nucleosynthetic isotope anomalies have been used to constrain the origins of material that formed Earth. However, anomalies have only been identified for elements with high condensation temperatures, leaving the origin of Earth’s volatile elements unconstrained. We determined the isotope composition of the moderately volatile element zinc in 18 bulk meteorites and identified nucleosynthetic zinc isotope anomalies. Using a mass-balance model, we find that carbonaceous bodies, which likely formed beyond the orbit of Jupiter, delivered about half of Earth’s zinc inventory. Combined with previous constraints obtained from studies of other elements, these results indicate that ~10% of Earth’s mass was provided by carbonaceous material.