The protracted Permo-Triassic crisis and multi-episode extinction around the Permian–Triassic boundary
The protracted Permo-Triassic crisis and multi-episode extinction around the Permian–Triassic boundary
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DOI：
10.1016/j.gloplacha.2006.06.005
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发表时间：
2007
影响因子：
3.9
通讯作者：
Hongfu Yin;Q. Feng;X. Lai;A. Baud;J. Tong
中科院分区：
文献类型：
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作者：
Hongfu Yin;Q. Feng;X. Lai;A. Baud;J. Tong
二叠纪-三叠纪危机是地质史上的一个重大转折点。在瓜达卢普世末期灭绝阶段之后，古生代生物群在洛平世（晚二叠世）期间经历了稳步下降，导致其在二叠纪-三叠纪边界（PTB）的水平上大量减少。这一趋势与最大的显生宙回归相吻合。因此，瓜达卢普纪末期的灭绝和标志着二叠纪末期的灭绝是相关的。随后生物群的恢复占据了整个早三叠世。 δ13C碳的几个扰动阶段发生在相似的时期，从晚五家坪世到早三叠世末。因此，二叠纪-三叠纪危机是旷日持久的，跨越了晚二叠世和早三叠世时期。与 PTB 相关的灭绝发生在两个情节中，即带有前奏的正剧和尾声。前奏开始于眉山 25 号和 26 号层之前，与二叠纪末期海退同时发生。主要情节发生在眉山的25号和26号床位。尾声发生在格里斯巴赫世晚期，与眉山第二火山形成层（28 层）重合。这些事件的时间分布限制了对最严重的显生宙大规模灭绝的机制的解释，特别是假设的火流星撞击的重要性，我们认为这种撞击可能发生在前奏后约 50,000 密尔。二叠纪-三叠纪危机的长期和多阶段性质有利于地球的内在演化机制，而不是外星灾难。显生宙最显着的回归、二叠纪-三叠纪混合超纪元的古地磁扰动、广泛分布的火山活动以及其他事件，可能都与盘古大陆整合过程中发生的深层过程有关。这些综合过程可能导致海洋、陆地和大气环境发生深刻变化，从而导致二叠纪末大规模灭绝。火流星撞击是可能的，但既不是对这些变化的充分解释，也不是必要的解释。
The Permo-Triassic crisis was a major turning point in geological history. Following the end-Guadalupian extinction phase, the Palaeozoic biota underwent a steady decline through the Lopingian (Late Permian), resulting in their decimation at the level that is adopted as the Permian–Triassic boundary (PTB). This trend coincided with the greatest Phanerozoic regression. The extinction at the end of the Guadalupian and that marking the end of the Permian are therefore related. The subsequent recovery of the biota occupied the whole of the Early Triassic. Several phases of perturbations in δ13Ccarboccurred through a similar period, from the late Wuchiapingian to the end of the Early Triassic. Therefore, the Permian–Triassic crisis was protracted, and spanned Late Permian and Early Triassic time. The extinction associated with the PTB occurred in two episodes, the main act with a prelude and the epilogue. The prelude commenced prior to beds 25 and 26 at Meishan and coincided with the end-Permian regression. The main act itself happened in beds 25 and 26 at Meishan. The epilogue occurred in the late Griesbachian and coincided with the second volcanogenic layer (bed 28) at Meishan. The temporal distribution of these episodes constrains the interpretation of mechanisms responsible for the greatest Phanerozoic mass extinction, particularly the significance of a postulated bolide impact that to our view may have occurred about 50,000 Myr after the prelude. The prolonged and multi-phase nature of the Permo-Triassic crisis favours the mechanisms of the Earth's intrinsic evolution rather than extraterrestrial catastrophe. The most significant regression in the Phanerozoic, the palaeomagnetic disturbance of the Permo-Triassic Mixed Superchron, widespread extensive volcanism, and other events, may all be related, through deep-seated processes that occurred during the integration of Pangea. These combined processes could be responsible for the profound changes in marine, terrestrial and atmospheric environments that resulted in the end-Permian mass extinction. Bolide impact is possible but is neither an adequate nor a necessary explanation for these changes.