Mercury evidence of intense volcanic effects on land during the Permian-Triassic transition
Mercury evidence of intense volcanic effects on land during the Permian-Triassic transition
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二叠纪-三叠纪过渡期间火山对陆地产生强烈影响的汞证据
作者：
Shen Jun;Yu Jianxin;Chen Jiubin;Algeo Thomas J.;Xu Guozhen;Feng Qinglai;Shi Xiao;Planavsky Noah J.;Shu Wenchao;Xie Shucheng
西伯利亚圈闭大火成岩省（STLIP）可能是这一事件的触发因素。252 Ma最新的二叠纪大灭绝（LPME），但全球火山对陆地影响的直接证据仍然罕见。本文利用汞（Hg）富集量作为古火山活动的代用指标，对两个陆地二叠-三叠系界线剖面--近赤道鲁北剖面（华南克拉通）和高纬度（40-60°N）大龙口剖面（准噶尔盆地）--进行了火山输入的研究。两个剖面在代表LPME的离散（≤40 m）地层窗内均表现出强烈的Hg富集。在鲁北，这段时间的特点也是负质量无关分馏（MIF）的奇数汞同位素，与大量的火山和/或陆地汞输入一致。这些研究结果是显着的记录汞峰值和负MIF漂移附近的PTB在陆地部分的第一次，提供证据的全球影响的STLIP，以及在高地层分辨率证明其同步性与PTB负碳同位素漂移（CIE），支持这些异常的一个共同的全球原因。
The Siberian Traps large igneous province (STLIP) was the likely trigger for the ca. 252 Ma latest Permian mass extinction (LPME), but direct evidence for global volcanic effects on land remains rare. Here, we used mercury (Hg) enrichments, a proxy for ancient volcanic activity, to assess volcanic inputs to two terrestrial Permian-Triassic boundary (PTB) sections that were separated by thousands of kilometers and represent different latitudinal zones—the peri-equatorial Lubei section (South China craton) and the high-latitude (40–60°N) Dalongkou section (Junggar terrane). Both sections exhibit strong Hg enrichment within a discrete (≤40 m) stratigraphic window representing the LPME. At Lubei, this interval is also characterized by negative mass-independent fractionation (MIF) of odd Hg isotopes, consistent with massive volcanogenic and/or terrestrial Hg inputs. These findings are significant in documenting Hg spikes and negative MIF excursions near the PTB in terrestrial sections for the first time, providing evidence of the global influence of the STLIP, as well as in demonstrating at high stratigraphic resolution its synchronicity with the PTB negative carbon-isotope excursion (CIE), supporting a common global cause for these anomalies.