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安徽巢湖平顶山西坡剖面近年来得以较全面的研究,成为早三叠世多重地层划分和对比的经典地质序列之一,也是进行奥伦尼克阶内部Smithian和Spathian亚阶界线定义的重要剖面.在前人研究的基础上,对该剖面Smithian-Spathian(S-S)界线附近地层中的牙形石生物地层学和碳同位素地层学进行再研究,更精确地标定了该界线的准确位置及界线附近碳同位素演变过程.以牙形石Neospathodus pingdingshanensis的首现点定义的S-S界线在剖面第52层+30cm处,该界线也是牙形石演变快速分异突变点;碳同位素曲线在S-S界线附近显著正向漂移,可作为该界线定义的重要参考标志.所得到的界线位置及碳同位素曲线均可进行全球对比.
In recent years, a comprehensive study of the western slope of Pingdingshan in Chaohu, Anhui Province has become one of the classic geological sequences for the division and contrast of multiple strata in the Early Triassic. It is also an important section for defining the boundary between the Smithian and Spathian sub-zeniths of the Olenonic Order. Based on previous studies, reexamining the conodontostatics and carbon isotope stratigraphy in the stratigraphic near the Smithian-Spathian (SS) boundary of the section, more accurately calibrated the exact location of the boundary and near the boundary carbon Isotope evolution process. The SS boundary defined by the first spot point of Neospathodus pingdingshanensis is also the rapid mutation point of conodont at the 52nd + 30cm section of the profile. The carbon isotope curve is significantly positive near the SS boundary Drift can be used as an important reference mark for the definition of the boundary The resulting boundary locations and carbon isotope curves are globally comparable.