More evidence that the Chicxulub impact predates the K/T mass extinction
More evidence that the Chicxulub impact predates the K/T mass extinction
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更多证据表明希克苏鲁伯撞击事件早于 K/T 大规模灭绝
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
Markus Harting
中科院分区：
文献类型：
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作者：
G. Keller;T. Adatte;W. Stinnesbeck;D. Stüben;Z. Berner;U. Kramar;Markus Harting
摘要在希克苏鲁布陨石坑内钻探的Yaxcopoil-1（Yax-1）有望最终证明这次撞击恰好发生在6500万年前，并导致白垩纪-第三纪（K/T）边界的大规模灭绝。相反，基于五个独立的替代物（沉积学、生物地层学、磁性地层学、稳定同位素和铱），发现了相反的证据，表明希克苏鲁布的撞击早于K/T边界约30万年，不可能导致大灭绝。这是证明了最新的马斯特里赫特区CF 1的五个bioturbated钙钛矿层和钙钛矿有孔虫组合的存在，并证实了磁性地层年代29 r和特征晚马斯特里赫特稳定同位素信号。这些结果首次出现在Keller等人（2004）中。在这项研究中，我们提出了更详细的证据，晚马斯特里赫特的南极有孔虫的存在，沉积学和矿物学分析表明，希克苏鲁布的影响角砾岩早于K/T边界和角砾岩和K/T边界之间的沉积物沉积在一个正常的海洋环境中，在过去的30万年的白垩纪。
Abstract Yaxcopoil‐1 (Yax‐1), drilled within the Chicxulub crater, was expected to yield the final proof that this impact occurred precisely 65 Myr ago and caused the mass extinction at the Cretaceous‐Tertiary (K/T) boundary. Instead, contrary evidence was discovered based on five independent proxies (sedimentologic, biostratigraphic, magnetostratigraphic, stable isotopic, and iridium) that revealed that the Chicxulub impact predates the K/T boundary by about 300,000 years and could not have caused the mass extinction. This is demonstrated by the presence of five bioturbated glauconite layers and planktic foraminiferal assemblages of the latest Maastrichtian zone CF1 and is corroborated by magnetostratigraphic chron 29r and characteristic late Maastrichtian stable isotope signals. These results were first presented in Keller et al. (2004). In this study, we present more detailed evidence of the presence of late Maastrichtian planktic foraminifera, sedimentologic, and mineralogic analyses that demonstrate that the Chicxulub impact breccia predates the K/T boundary and that the sediments between the breccia and the K/T boundary were deposited in a normal marine environment during the last 300,000 years of the Cretaceous.