Late accretion history of the terrestrial planets inferred from platinum stable isotopes
Late accretion history of the terrestrial planets inferred from platinum stable isotopes
复制标题
DOI：
10.7185/geochemlet.1710
复制
发表时间：
2017-01-01
影响因子：
4.9
通讯作者：
Bizzarro, M.
中科院分区：
文献类型：
--
作者：
Creech, J. B.;Baker, J. A.;Bizzarro, M.
球粒物质向分化的行星体的晚期吸积被认为在早期太阳系中是常见的。然而，将这种物质掺入类地行星的时间和规模都没有得到很好的限制。利用一系列太阳系天体的铂（Pt）稳定同位素数据，我们发现地球太古宙后地幔具有球粒质198Pt/194Pt，这与地核形成后添加的球粒质晚覆层相一致。相反，陆地太古宙样品记录了非球粒质、重质198Pt/194Pt，表明保存了早期地幔成分，没有与晚期饰面完全混合。这些数据表明混合
Late accretion of chondritic material to differentiated planetary bodies is thought to have been common in the early solar system. However, the timing and scale of admixing this material to terrestrial planets are poorly constrained. Using platinum (Pt) stable isotope data in a range of solar system bodies, we show that Earth's post-Archean mantle has chondritic 198Pt/194Pt, consistent with addition of a chondritic late-veneer after core formation. Conversely, terrestrial Archean samples record non-chondritic, heavy, 198Pt/194Pt, indicating preservation of early mantle components that escaped complete mixing with the late-veneer. These data suggest admixing of