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煤山剖面二叠纪-三叠纪过渡期24～29层微观地层特征,清晰地显示了这一关键地层段持续的缺氧及频发的风暴扰动、固结基底/硬底构造、火山喷发、陆地风化和丘状微生物岩发育等事件的整体时序关系,为综合探讨二叠纪末期生物灭绝的机制提供依据.晚二叠世长兴组24层以发育有机质微细纹层为主,间断性受到风暴形成的底流冲刷,暗示这一时期静滞、分层和缺氧的海洋主体环境.晚二叠世末期快速海侵事件发生于24d层顶部,以典型的硬底构造发育为特征.持续的陆源火山物质风化和向海洋搬运沉积,使得以伊利石为主的黏土矿物广泛存在并贯穿二叠纪生物灭绝事件的整个过程.但是,发育正粒序火山玻屑的25层“界线黏土”却是强烈的火山喷发物在海洋直接沉降的结果.表现在27-2层上部的固结基底构造,发育Glossifungites遗迹等强烈生物扰动和塑性基底特征,代表着与牙形刺Hindeodus parvus的开始出现相一致的快速海侵事件的发生.27-5层微弱的丘状微生物岩的首次发现,表明华南浅水碳酸盐台地发育的微生物岩应属于早三叠世最早期,同时也代表了二叠纪末生物灭绝事件的最终结束.
The Michel stratigraphic features of the Permian-Triassic transitional stages from the Meishan section to the 24th to 29th strata clearly show the continued hypoxia and frequent storm disturbance in this key formation, the consolidated base / hard bottom structure, volcanic eruptions , Land weathering and mound microbial rock development events provide a basis for comprehensive exploration of the mechanism of end-stage Permian extinction.The late Permian Changxing Formation layer 24 is dominated by the development of fine lines of organic matter, intermittent by The underflow erosion caused by the storm implied a static, stratified and anoxic marine host environment during this period.The rapid transgression of Late Pleistocene occurred at the top of layer 24d and was characterized by typical hard-bottom structural development. The terrigenous volcanic material weathered and transported to the ocean sediment, making the illite-dominated clay mineral widespread throughout the Permian biotic extinction event throughout. However, the development of 25-layer “graded vitrinite ”Is the result of intense direct volcanic eruptions in the oceans, which are characterized by strong bioturbation and plastic basement features such as the Glossifungites ruins that represent the consolidated basement structure above the 27-2th floor, The onset of a consistent rapid transcontinental event occurred at the beginning of the conodonts Hindeodus parvus, and the first discovery of weak foraminifera rocks in the 27-5 layer indicates that the microfacies developed in the shallow-water carbonate platform of southern China should belong to the most part of the Early Triassic Early, but also represents the end of Permian end extinction event.