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通过对分别位于台地、斜坡和盆地的广西合山马滩剖面、来宾铁桥剖面和来宾蓬莱滩剖面的廊带式追索研究，将二叠系乐平统地层自下而上划分为Ｌｐ１、Ｌｐ２、Ｌｐ３、Ｌｐ４、Ｌｐ５和Ｌｐ６６个三级层序，并建立了相应的海平面变化曲线。结合原有和最新的生物地层资料，对这３个剖面的层序地层划分实现了精确对比，从而将原有地层对比精度提高了１倍。主张以牙形石Ｃｌａｒｋｉｎａｓｕｂｃａｒｉｎａｔａ的初现作为长兴阶和吴家坪阶的分界，这一界线与上述三级层序Ｌｐ６的首次海泛面一致。长期被当作长兴阶下部带化石的Ｇａｌｏｗａｙｉｎｅｌａｍｅｉｔｉｅｎｅｎｓｉｓ和Ｐａｌａｅｏｆｕｓｕｌｉｎａｍｉｎｉｍａ可向下延入依据牙形石定义的吴家坪阶。
The Permian Lepingtong Formation is divided into Lp1, Lp2 and Lp2 by the study of the belt-strait reclamation in the section of Heshanmaotan, Laipeiziqiao and Laibinlailantan in Guangxi, which are respectively located on the platform, slope and basin. , Lp3, Lp4, Lp5 and Lp66 third-order sequences, and established the corresponding sea level curve. Combined with the original and latest biogenic stratum data, the stratigraphic sequence stratigraphic division of these three sections is precisely compared, thus doubling the original stratum contrast precision. It is suggested that the beginning of the conodont of Clarkinasubcarinata be used as the boundary of Changxing and Wujiaping stages, which is in line with the first sea-level aspect of the third-order sequence Lp6. Galowayinelameitienensis and Palaeofusulinaminima, which have long been regarded as fossils in the lower Changxinghang, can extend downward into the Wujianping stage defined by conodont.