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根据岩相序列、沉积、成岩作用特征，将吉林省大阳岔地区晚寒武世凤山期至早奥陶世冶里期层序地层分为６个三级层序，代表了６个三级海侵—海退旋回；与之相应，该时期碳酸盐岩δ１３Ｃ值变化曲线出现５个低谷，其中凤山期至冶里早期泥晶灰岩δ１３Ｃ值出现４次幅度较大的上升、下降飘移，而冶里中、晚期泥晶灰岩的δ１３Ｃ值是在负值范围内波动。δ１３Ｃ值低谷与层序界面和海退事件基本拟合。牙形类Ｃ．ｉｎｔｅｒｍｅｄｉｕｓ带下部海绿石质凝缩段是寒武纪末—奥陶纪初期最大海泛事件沉积，也是寒武纪与奥陶纪之交等时性的年代地层对比标志。
According to the characteristics of lithofacies sequence, sedimentation and diagenesis, the Late Cambrian sequence of the Fengshan-Early Ordovician sequence in the Dayangcha area, Jilin Province, is divided into 6 third-order sequences, representing 6 third-order sea In response, the δ13C values of carbonate rocks show five troughs in this period, and the δ13C values of the four phases of the Fengjing uplift to Yeli limestone show a large increase and drop drift , Whereas the δ13C values of the middle and later metamorphic limestones in Yeli fluctuated within the negative range. The δ13C value trough was basically fitted with the sequence boundary and regression. Teeth C Intermediates of chlorophyll condensation in the lower part of intermedius are the Cambrian end - the largest event of marine flooding in the early Ordovician period, and also an isochronous chronostratigraphic contrast marker at the turn of Cambrian and Ordovician.