The terrestrial end-Permian mass extinction in South China
The terrestrial end-Permian mass extinction in South China
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DOI：
10.1016/j.palaeo.2015.07.002
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发表时间：
2016-04
期刊：
影响因子：
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通讯作者：
Hua Zhang;Changqun Cao;Xiao-Lei Liu;Lin Mu;Quan‐Feng Zheng;Feng Liu;L. Xiang;Lu-jun Liu;S. S
中科院分区：
文献类型：
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作者：
Hua Zhang;Changqun Cao;Xiao-Lei Liu;Lin Mu;Quan‐Feng Zheng;Feng Liu;L. Xiang;Lu-jun Liu;S. S
二叠纪末的大灭绝反映了显生宙最严重的生命危机，并与重大的全球环境变化有关。然而，陆地和海洋物种灭绝的时间和模式的一致性仍然存在争议。本文对华南陆相剖面的高分辨率生物地层和地球化学资料进行了详细分析。分析表明，过渡时期的凯头组实际上记录了陆生大灭绝的过程，下部为巨翼植物群的大量消失，中部为巨形植物群的大量减少，上部为最后出现的植物遗迹和丰富的木炭化石。δ13Corg从组中部开始有明显的负移，与海相眉山剖面26层顶部的δ13Corg负移相关。此外，开头组下部的鲜湖沼泽或河流平坦环境的岩相变化明显，由下部的橄榄色/灰色/黑色泥岩、粉砂岩、细砂岩到粗砂岩逐渐增多的栗色岩，再到下部含角砾岩、钙质古溶质和钙质结节的纯栗色泥岩；这表明土壤系统的急剧崩溃与快速砍伐森林和气候变暖和干燥有关。在沿海地区，卡头组含典型的二叠系-三叠系混合动物群，与眉山最新的长兴期海洋混合动物群1相对应。开头组也有明显的海侵，开始于长兴期晚期。这些现象表明，凯头组实际上是二叠纪末陆生生物大灭绝的见证；大部分或全部属于长兴期晚期（二叠纪），而不是三叠纪。
The end-Permian mass extinction reflects the most severe life crisis during the Phanerozoic and was associated with major global environmental changes. However, the consistency of the time and pattern of the terrestrial and marine extinctions remains controversial. In this paper, we presented detailed analyses of the high-resolution biostratigraphical and geochemical data from terrestrial sections in South China. Our analyses show that the transitional Kayitou Formation actually recorded the process of terrestrial mass extinction as evidenced by the mass disappearance of theGigantopterismegaflora in the lower part, the dramatic reduction in abundance of palynomorphs in the middle, and the last occurrences of plant remains and abundant charcoal fossils in the uppermost part. It is associated with a distinct negative shift of δ13Corg, beginning in the middle part of the formation, which is correlative with that in the top of Bed 26 at the marine Meishan section. In addition, the Kayitou Formation is characterized by a distinct shift of lithofacies of fresh lake-swamp or river flat environment from olive/grey/black mudstone, siltstone, fine to coarse sandstone in the lower part to gradually increasing maroon rocks, to purely maroon mudrocks with poorly-sorted breccia, calcic palaeosols and calcareous nodules in the lowest part of the Dongchuan Formation, which indicates a dramatic collapse of soil system associated with rapid deforestation and climatic warming and drying. In the coastal area, the Kayitou Formation contains marine beds with the typical Permian–Triassic mixed faunas and floras which are correlative with the latest Changhsingian marine mixed fauna 1 at Meishan. The Kayitou Formation also recorded a distinct transgression that began in the latest Changhsingian. All above phenomena suggest that the Kayitou Formation is actually the witness of the terrestrial end-Permian mass extinction; and it is mostly or entirely of latest Changhsingian (Permian), rather than Triassic age.