Age and Timing of the Permian Mass Extinctions: U/Pb Dating of Closed-System Zircons
Age and Timing of the Permian Mass Extinctions: U/Pb Dating of Closed-System Zircons
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DOI：
10.1126/science.1101012
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发表时间：
2004-09
期刊：
影响因子：
56.9
通讯作者：
R. Mundil;K. Ludwig;I. Metcalfe;P. Renne
中科院分区：
文献类型：
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作者：
R. Mundil;K. Ludwig;I. Metcalfe;P. Renne
二叠纪-三叠纪大灭绝的年龄和时间一直难以确定，因为锆石人口的典型部分是普遍的铅损失和污染的影响，难以区分的旧捕虏晶。来自上思和梅山剖面（中国）的9个灰层的锆石，经过退火预处理，然后用氢氟酸进行部分侵蚀，得到了一套一致和一致的铀/铅（U/Pb）年龄，消除了铅损失的影响。这次生物大灭绝的主脉冲U/Pb年龄为252.6 ± 0.2百万年，与西伯利亚洪水火山作用同步，发生在引用的不确定度范围内。
The age and timing of the Permian-Triassic mass extinction have been difficult to determine because zircon populations from the type sections are typically affected by pervasive lead loss and contamination by indistinguishable older xenocrysts. Zircons from nine ash beds within the Shangsi and Meishan sections (China), pretreated by annealing followed by partial attack with hydrofluoric acid, result in suites of consistent and concordant uranium/lead (U/Pb) ages, eliminating the effects of lead loss. The U/Pb age of the main pulse of the extinction is 252.6 ± 0.2 million years, synchronous with the Siberian flood volcanism, and it occurred within the quoted uncertainty.