The base of the Lystrosaurus Assemblage Zone, Karoo Basin, predates the end-Permian marine extinction
The base of the Lystrosaurus Assemblage Zone, Karoo Basin, predates the end-Permian marine extinction
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DOI：
10.1038/s41467-020-15243-7
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发表时间：
2020-03-18
影响因子：
16.6
通讯作者：
Martini, Anna M.
中科院分区：
文献类型：
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作者：
Gastaldo, Robert A.;Kamo, Sandra L.;Martini, Anna M.
目前的模式为结束二叠纪陆地生态系统危机认为，系统性的损失表现出的突然营业额从Daptocephalus的Lystrosaurus组合区（AZ;卡鲁盆地，南非）的时间相当于海洋二叠纪-三叠纪边界（PTB）。海洋事件开始于251.9410.037Ma，PTB位于251.902 +/- 0.024Ma（2 sigma）。卡鲁盆地这段时间的放射性同位素测年仅限于Daptocephalus AZ上部的一个高分辨率火山灰降落存款（253.48 +/- 0.15（2 sigma）Ma），上覆生物带没有类似的年龄限制。在这里，我们提出了第一个U-Pb CA-ID-TIMS锆石年龄（252.24 +/- 0.11（2西格玛）马）从原始灰落存款在卡鲁Lystrosaurus AZ。这一日期证实了Lystrosaurus AZ的下部暴露是最新的二叠世时代，并且据称该盆地的更替早于二叠世末海洋事件300 ka以上，从而反驳了之前使用的陆地二叠世末灭绝的地层标记。p id=Par二叠纪末与海洋和陆地生物多样性的重大变化有关。在这里，Gastaldo等人对南非卡鲁盆地的水龙龙组合区进行了高分辨率的年代测定，证明海洋危机并不反映陆地上的同时代事件。
The current model for the end-Permian terrestrial ecosystem crisis holds that systematic loss exhibited by an abrupt turnover from the Daptocephalus to the Lystrosaurus Assemblage Zone (AZ; Karoo Basin, South Africa) is time equivalent with the marine Permian-Triassic boundary (PTB). The marine event began at 251.9410.037Ma, with the PTB placed at 251.902 +/- 0.024Ma (2 sigma). Radio-isotopic dates over this interval in the Karoo Basin were limited to one high resolution ash-fall deposit in the upper Daptocephalus AZ (253.48 +/- 0.15 (2 sigma) Ma) with no similar age constraints for the overlying biozone. Here, we present the first U-Pb CA-ID-TIMS zircon age (252.24 +/- 0.11 (2 sigma) Ma) from a pristine ash-fall deposit in the Karoo Lystrosaurus AZ. This date confirms that the lower exposures of the Lystrosaurus AZ are of latest Permian age and that the purported turnover in the basin preceded the end-Permian marine event by over 300 ka, thus refuting the previously used stratigraphic marker for terrestrial end-Permian extinction. p id=Par The end-Permian is associated with major changes in both marine and terrestrial biodiversity. Here, Gastaldo et al. present high resolution dating of the Lystrosaurus Assemblage Zone in the Karoo Basin, South Africa, demonstrating that the marine crisis did not mirror a coeval event on land.