Lower Triassic carbonate δ238U record demonstrates expanded oceanic anoxia during Smithian Thermal Maximum and improved ventilation during Smithian-Spathian boundary cooling event
Lower Triassic carbonate δ238U record demonstrates expanded oceanic anoxia during Smithian Thermal Maximum and improved ventilation during Smithian-Spathian boundary cooling event
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下三叠统碳酸盐岩 δ238U 记录表明，史密斯热最大值期间海洋缺氧扩大，史密斯-斯帕蒂边界冷却事件期间通风改善
DOI：
10.1016/j.palaeo.2019.109393
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Li Ziheng
中科院分区：
文献类型：
--
作者：
Zhao He;Algeo Thomas J;Liu Yongsheng;Chen Zhong-Qiang;Zhang Lei;Hu Zhaochu;Li Ziheng
smith - spathian边界（SSB）过渡最近被确定为二叠纪末大灭绝后海洋生态系统恢复道路上的主要生物危机。据推测，海洋缺氧在SSB生物危机中发挥了重要作用。然而，由于对smith - spathian （S-S）过渡期间缺氧的时间、持续时间和程度的了解有限，对这一生物危机与同期海洋氧化还原条件之间关系的理解受到了阻碍。本文给出了华南嘉荣剖面中史密斯统至斯巴达统中段的高分辨率碳酸盐u同位素记录。该记录显示，在史密斯期晚期δ238U值持续为负（平均为- 0.56‰），随后在整个南海迅速正移（从- 0.78‰到- 0.10‰），然后在斯帕塔期早期至中期更缓慢地回到较低的δ238U值。U同位素质量平衡模型表明，全球缺氧海底面积在史密斯晚期和斯巴达期早期至中期明显扩大，但在S-S过渡期间急剧缩小。这种氧化还原模式与先前发表的热带海表温度（SST）记录非常吻合，海洋缺氧峰值与史密斯热极大期（STM）一致，而在SSB明显的全球变冷事件期间，缺氧减少。虽然古生物学记录通常不区分史密斯晚期和南中国海时期的灭绝，但我们假设南中国海时期的生物危机主要与南中国海时期有关，其特征是牙形刺、菊石和其他海洋无脊椎动物的多样性急剧丧失，在这种情况下，海洋缺氧可能是奥伦基中期海洋生物的主要压力源。
The Smithian-Spathian boundary (SSB) transition was recently identified as a major biocrisis on the road to marine ecosystem recovery following the end-Permian mass extinction. Marine anoxia is hypothesized to have played an important role in the SSB biocrisis. However, an understanding of the relationship of this biocrisis to contemporaneous marine redox conditions has been hampered by limited knowledge of the timing, duration, and extent of anoxia during the Smithian-Spathian (S-S) transition. Here, we present a high-resolution carbonate U-isotope record from the Jiarong section of South China that spans the mid-Smithian to mid-Spathian interval. This record shows persistent negativeδ238U values (averaging −0.56‰) in the late Smithian, followed by a rapid positive shift (from −0.78‰ to −0.10‰) across the SSB, and then a more gradual shift back to lower δ238U values in the early to mid-Spathian. U isotope mass balance modeling suggests that the global area of anoxic seafloor expanded strongly during the late Smithian and the early to mid-Spathian but contracted sharply during the S-S transition. This redox pattern shows an excellent correspondence to previously published tropical sea-surface temperature (SST) records, with peak oceanic anoxia coinciding with the Smithian Thermal Maximum (STM) and diminished anoxia during a pronounced global cooling event at the SSB. Although paleontological records commonly do not distinguish between terminations during the late Smithian and SSB, we hypothesize that the SSB biocrisis, which was marked by sharp diversity losses among conodonts, ammonoids, and other marine invertebrates, was primarily associated with the STM, in which case oceanic anoxia is likely to have been a major stressor of mid-Olenekian marine biotas.
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影响因子：
5.3
作者：
Galfetti, Thomas;Bucher, Hugo;Guodun, Kuang
通讯作者：
Guodun, Kuang
牙形刺白牙冠中的稀土元素模式：最近二叠纪生物危机期间火山灰大量输入的证据？
影响因子：
3.9
作者：
Gao, Shan;Zhou, Lian;Hu, Zhaochu;Liu, Yongsheng
通讯作者：
Liu, Yongsheng
影响因子：
1.4
作者：
Linda C. Kah;Anne G. Sherman;G. Narbonne;A. Knoll;A. J. Kaufman
通讯作者：
Linda C. Kah;Anne G. Sherman;G. Narbonne;A. Knoll;A. J. Kaufman
影响因子：
5
作者：
Chen, Xinming;Romaniello, Stephen J.;Anbar, Ariel D.
通讯作者：
Anbar, Ariel D.
DOI：
10.1073/pnas.1515080113
发表时间：
2016-03-01
影响因子：
11.1
作者：
Lau, Kimberly V.;Maher, Kate;Payne, Jonathan L.
通讯作者：
Payne, Jonathan L.