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坟头组时代争论长期不能统一的原因之一，在于各家对坟头组涵盖范围理解不一。坟头组有广义和狭义之分：以侯家塘组的顶为底、以秀山动物群的最高层位为顶的坟头组概念，为狭义坟头组。以侯家塘组、茅山组之间岩层的总和作为坟头组的概念，为广义坟头组。本文建议使用狭义坟头组概念，以求定义统一。坟头组之上、茅山组之下还存在寨山组和新河庄组（新组）。宁镇山脉志留系存在倒序、脱顶、丢层等问题，建议将坟头组、寨山组的标准剖面选在安徽铜陵寨山剖面；新河庄组的标准剖面选在安徽宣城新河庄剖面。根据胞石带的研究，坟头组顶界穿时，其时代为Ｔｅｌｙｃｈｉａｎ晚期至Ｗｅｎｌｏｃｋ世早期。寨山组底界穿时，顶界时代为Ｌｕｄｌｏｗ世末期；新河庄组的时代为Ｐｒｉｄｏｌｉ世早、中期；茅山组的时代推测仅限于Ｐｒｉｄｏｌｉ世晚期。本文还对“管状砂岩”的时代、秀山动物群回归的时代、红层与冰川的关系、海平面升降、分统建阶及古地理再造等问题作了讨论。
One of the reasons for the long-standing dispute over the Mound Group era lies in the various understandings of the coverage of the Mound Group. Mud group has a broad and narrow sense: the top of the Houjiatang group to the bottom of the Xiushan fauna as the top of the concept of grave group, the narrow grave group. To Hou Jiantang group, Maoshan group between the rock formation as the concept of group of mounds for the broad mound group. This paper suggests the use of the concept of narrow grave groups in order to define unity. Above the Moutan group, there are also Zhaishan Formation and Xinhezhuang Formation (New Formation) under the Maoshan Formation. It is suggested that the standard section of the Menshan Formation and the Zhaishan Formation should be selected at the Zhaoshan section of Tongling, Anhui Province. The standard section of the Xinhezhuang Formation is selected from the Xuan River Zhuang section. According to the study of the ophiolites, the time from the top of the grave group to the time of the early Telychian to early Wenlocks. When the bottom of the Zhaishan Formation was worn, the top boundary was the end of the Ludlow Era; the age of the Xinhezhuang Formation was Pridoli’s early and middle stages; and the epoch of the Maoshan Formation was confined to the late Pridoli. The paper also discusses the problems of “tubular sandstone”, the return of Xiushan fauna, the relationship between red beds and glaciers, the sea level rise and fall, the establishment of the sub-system and the re-creation of paleogeography.