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通过对浙江长兴煤山二叠-三叠系界线全球层型剖面附近钻孔岩芯的研究,识别出遗迹化石Chondrites,Palaeophycus,Planolites,Rhizocorallium,Skolithos,Thalass-inoides共6属,遗迹化石的丰度、扰动指数及扰动深度等遗迹学指标在二叠-三叠系界线上下呈现两幕式剧烈变化:第一幕发生在25~27b,在此区间,生态习性相对复杂的Chondrites,Skolithos,Rhizocorallium和Thalassinoides遗迹化石从此逐步消失,扰动指数从1~5级降低至1~3级,扰动深度从5~66cm降低至2~5cm;第二幕发生在32层与33层之间,Palaeophycus和Planolites遗迹消失,33层至41层下部未见任何遗迹和扰动现象,41层中上部遗迹再次出现,但仅见简单细小的Planolites,扰动指数再未超过3级,扰动深度小于4mm.第一幕变化较为剧烈,对应于二叠纪末生物灭绝主幕;第二幕相对较弱,对应于造迹生物在早三叠世初的灭绝尾幕;随后出现的遗迹以生态习性和结构简单的表生潜穴占绝对优势,这表明经历了二叠纪末大灭绝沉重打击后,早三叠世初残存期的底栖生态系由表生固着向表生游移转折.也就是说,二叠-三叠纪之交遗迹化石的演变与实体化石的演变有着相似的幕式变化过程与趋势.另外,二叠-三叠纪之交遗迹组构的变化与碳同位素负偏、蓝细菌泛滥之间也存在良好的对应关系.作为物理过程与生物过程相互作用的产物,遗迹化石在研究二叠-三叠纪之交的生物和环境事件及其耦合关系和演变规律方面,提供了独特的材料,具有重要的启示意义.
Through the study of the core drilling near the global stratigraphic section of the Permian-Triassic boundary in the Meishan, Changxing, Zhejiang Province, six fossils of Chondrites, Palaeophycus, Planolites, Rhizocorallium, Skolithos and Thalasso-inoides have been identified. There are two episodes of dramatic changes in the Permian-Triassic boundary: the first occurs in 25-27b, and in this interval, Chondrites, Skolithos, Rhizocorallium with relatively complex ecological habits And the Thalassinoides trace fossils disappeared gradually. The disturbance index decreased from 1 to 5 to 1 to 3 and the disturbance depth decreased from 5 to 66 cm to 2 to 5 cm. The second occurred between 32 and 33 levels. Palaeophycus and Planolites The remains disappeared, and no relics and disturbances were observed in the lower part of the 41st floor to the 41st floor, and the middle and upper relics of the 41st floor reappeared, but only simple and small Planolites showed no disturbance index of more than 3 and a disturbance depth of less than 4mm Intense, corresponding to the end of the Permian extinction of the main curtain; Act II is relatively weak, corresponding to the extinction of the end of the Early Triassic Creatures tail; subsequent relics to ecological habits and simple structure of the table The absolute potential of the burrows indicates that after the end of Permian catastrophic massacre, the benthic ecosystem in the early Triassic remnants transition from superficial fixation to superficial migration, that is to say, Permian-Tri The evolution of trace fossils at the turn of the fold is similar to that of the fossil fossils in the evolutionary process.Furthermore, changes in the fabric structure of the Permian-Triassic dating from the negative phase of carbon isotope and the spread of cyanobacteria As a product of the interaction between physical processes and biological processes, trace fossils provide a unique material for studying biological and environmental events and their coupling and evolution at the turn of the Permian-Triassic period with Important revelation.