Lovina, classified as an ungrouped ataxite, is controversial and its identity as a meteorite has been questioned. In this work, we use Pb isotopes on targeted troilite nodules in Lovina as a test of its antiquity and provenance. Although precise ages cannot be obtained, LA‐ICP‐MS offers a rapid, straightforward procedure to establish the source of lead, whether ancient (meteoritic) or modern (terrestrial). For nine pristine, unweathered nodules in Lovina, we find a lead isotopic composition of: ²⁰⁶Pb/²⁰⁸Pb = 0.492 ± 0.003 (2σ, MSWD 0.79; 95%) and ²⁰⁷Pb/²⁰⁶Pb = 0.852 ± 0.003 (2σ, MSWD 1.09; 95%) with no detectable uranium. All lead compositions of the troilite fall in the range expected for modern environmental and mantle lead and are distinctly different from the primordial Canyon Diablo Troilite (CDT) composition of ancient meteoritic troilite. Although the origin of Lovina remains unknown, we conclude that lead in the Lovina troilite is unsupported by U decay and originated from a terrestrial source.

中文翻译：

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陨石来源的LA‐ICP‐MS Pb同位素测试：罗威那的陆地起源

罗威那（Lovina）被归类为未分组的紫杉醇，颇受争议，其作为陨石的身份也受到质疑。在这项工作中，我们在罗威那州的有针对性的三叶草结核上使用铅同位素作为其古代和起源的检验。尽管无法获得准确的年龄，但是LA‐ICP‐MS提供了一种快速，直接的程序来确定铅的来源，无论是古老的（气象学的）还是现代的（地面的）。对于罗威那的9个原始的未风化结节，我们发现铅同位素组成为：²⁰⁶ Pb / ²⁰⁸ Pb = 0.492±0.003（2σ，MSWD 0.79; 95％）和²⁰⁷ Pb / ²⁰⁶Pb = 0.852±0.003（2σ，MSWD 1.09; 95％），未检出铀。三叶草的所有铅成分均落入现代环境和地幔铅的预期范围内，并且与古代陨石三叶草的原始峡谷暗黑破坏神三叶虫（CDT）成分明显不同。尽管Lovina的起源尚不清楚，但我们得出的结论是，Lovina三叶草中的铅不受U衰变的支持，并且来自陆源。