“震旦系”是我国最早提出并普遍使用的一个时间地层单位。1922年葛利普在其论“震旦系”的文章里,大致规定它的含义是:“在寒武系之下,变质的更老岩系(五台或泰山岩系)之上的未变质或浅变质的沉积层”。1924年,李四光记述了长江峡东区不整合覆于变质的三斗坪群之上,整合伏于寒武纪含三叶虫化石的石碑页岩之下的一套不变质地层,并援引葛利普定义而命名为震旦系。由于相当地层在我国南方分布广泛,出露清楚,其上与寒武系紧密相连,下有晋宁运动造成的不整合为界,其中还有冰碛岩作为标志层。因而,随着地层研究工作的逐步深入,以南方型的震旦系作为震旦系的标准,并作为前寒武系顶部的“系”一级的地层单位,已经被越来越多的地质学者所重视或接受。但是,不用 The “Sinian System” is one of the earliest time strata units proposed and commonly used in our country. In his 1922 article on “Sinian,” Galip roughly laid out its meaning as follows: “Under the Cambrian, the metamorphic older rock series (Wutai or Taishan rock series) are not metamorphosed or Shallow metamorphic sedimentary layer. ” In 1924, Li Siguang described the unconformity of the Changjiang Gorge area over the metamorphosed Sandouping Group and the consolidation of a set of non-degenerate strata underlying the stele shale containing the trilobite fossils in the Cambrian era. Citing the definition of Galip, And named for the Sinian Department. Due to the distribution of considerable strata in the southern part of our country, which are widely distributed and clearly exposed, they are closely linked with the Cambrian. There are unconformities caused by the Jinning movement, with the moraine rocks as the indicator layer. Therefore, with the gradual deepening of stratigraphic research, the southern Sinian system, as the standard of the Sinian system and as the stratigraphic unit of the “Department” at the top of the Precambrian, has been more and more geological Scholars value or accept. But no