Latest Permian mercury anomalies
Latest Permian mercury anomalies
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DOI：
10.1130/g32596.1
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发表时间：
2012
期刊：
影响因子：
5.8
通讯作者：
H. Sanei;S. Grasby;B. Beauchamp
中科院分区：
文献类型：
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作者：
H. Sanei;S. Grasby;B. Beauchamp
加拿大高北极布坎南湖剖面的沉积记录显示，在最新的二叠纪灭绝（LPE）期间，泛古陆西北部的汞（Hg）含量异常高。大量汞的涌入逐渐淹没了海洋系统。有机物介导的汞下降过程的重大中断导致溶解汞在LPE边界处积累到最高水平，影响已经紧张的全球生态系统。在LPE边界切换到缺氧海洋条件导致汞硫化物的化学下降，标志着汞的逐步缓解。这使得汞能够从有毒的汞环境中自我恢复，并最终导致内部汞-有机物下降过程的重建。我们推测，异常的汞水平可能是由于重大的自然大气排放造成的灾难性西伯利亚火山喷发。
A sedimentary record from the Buchanan Lake section, Canadian High Arctic, shows anomalous high levels of mercury (Hg) during the latest Permian extinction (LPE) on northwest Pangea. Significant influx of Hg progressively overwhelmed the marine system. Major disruption of the organic matter–mediated Hg drawdown process resulted in accumulation of dissolved Hg to maximum levels at the LPE boundary, affecting an already stressed global ecosystem. A switch to euxinic marine conditions at the LPE boundary led to chemical drawdown of Hg sulfides, as marked by progressive Hg mitigation. This allowed self-recovery from toxic Hg conditions, and ultimately led to reestablishment of the internal Hg–organic matter drawdown process. We hypothesize that anomalous Hg levels may be attributed to the significant natural atmospheric emissions caused by catastrophic Siberian Traps volcanic eruptions.