一、前言苏、浙、皖地区石炭系分布广泛,发育较全,含化石较丰富,地层时代和划分的分歧也较少。长期以来,关于中、下石炭统的分界,一直沿用李四光(1930)、朱森等(1935)对宁镇山脉的研究成果,以黄龙组下部白云岩底部的假整合面(即淮南运动),作为二者的分界线。但近十年来,这一分界线似乎又成为一个争论的问题。有些地质古生物工作者 I. Preface The Carboniferous in the areas of Jiangsu, Zhejiang and Anhui are widely distributed and developed, with rich fossils and few differences in stratigraphic age and division. For a long time, the demarcation of the Middle and Lower Carboniferous has been based on the research results of Li Siguang (1930), Zhu Sen et al. (1935) on the Ningzhen Mountains, the fake integrative surface of the lower part of the Huanglong Formation (ie, the Huainan Campaign) As the dividing line between the two. But in the past decade, this dividing line seems to have become a matter of debate. Some geological paleontologists