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江西乐平沿沟二叠系-三叠系界线剖面为连续碳酸盐岩相序列,较完整地记录了二叠纪-三叠纪之交重大突变期浅水非微生物岩相区的生物和环境演变过程.通过对该剖面高精度的牙形石生物地层和碳酸盐岩微相研究,可以很好地界定该剖面二叠系-三叠系界线地层序列,并与煤山标准剖面精确对比.借助于系列岩石切片观察,可将界线地层序列归入6种不同的碳酸盐岩微相类型,借此探讨该重大突变过程中沉积环境变化及其与生物演变之间的关系.综合沉积微相、生物化石和碳同位素的对比研究,发现微相MF-4(含被包壳的有孔虫亮晶鲕状灰岩)和微相MF-6(深色生物介壳灰岩)是两次重大生物灭绝和环境变化事件的不同沉积响应,这两次事件均与华南和全球其他地区有相似性和可比性.其中MF-4是华南二叠纪末发育有鲕状灰岩的首次报道,代表了二叠纪末可能就已经出现高二氧化碳分压、低硫酸盐浓度和微生物繁盛等异常环境状态;而MF-6中发育丰富的腹足类和介形虫,则代表了在三叠纪最早期存在一次腹足类和介形虫的繁盛事件.沿沟剖面碳酸盐岩微相分布较完整地体现了二叠纪-三叠纪之交重大突变期浅水非微生物岩相区生物和环境的幕式演变历程,是煤山标准剖面的重要补充.
The Permian-Triassic boundary section along the Leping, Leping, Jiangxi, is a continuous carbonatite facies series, which completely records the biological and environmental evolution of the non-microbial facies in the shallow water during the Permian-Triassic significant catastrophe The sequence of Permian-Triassic boundary stratigraphy can be well defined by the study of the high-precision conodont biostratigraphy and carbonate microfacies of this section, which is exactly compared with the standard section of coal seam. With the help of the series of rock slice observations, the boundary stratigraphic sequences can be classified into six different carbonate microfacies types to explore the relationship between sedimentary environment changes and their biological evolution during this major catastrophe. Phases, fossils and carbon isotopes were compared and it was found that the microfacies MF-4 (with the encrusted foraminiferal glitter oolite limestone) and the microfacies MF-6 (dark biomask limestone) were found to be twice Different depositional responses of major biological extinction and environmental change events, both of which have similarities and comparability with South China and other parts of the world, of which MF-4 was the first report of the development of oolite limestone at the end of the Permian in South China, On behalf of the end of the Permian may have appeared sophomore Carbon partial pressure, low sulfate concentration and microbial flourishing and other abnormal environmental conditions; and MF-6 rich in gastropods and ostracods, represents the earliest in the Triassic there gastropod and in the first The flourishing event of the worm.The distribution of carbonate microfacies along the profile of the ditch more fully embodies the evolutionary process of the biological and environmental aspects of the non-microbial facies in the shallow water during the period of Permian-Triassic significant mutation, An important addition to the standard profile.