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新元古代的冰期事件一直是地质界研究的热点之一。包括中国在内 ,世界许多地区新元古代地层中普遍发育有一至两层冰碛岩 ,有的地区甚至可以见到三层冰碛岩 ,在冰碛岩之上往往有碳酸盐岩盖层 ( Cap Carbonate)。通过对皖南休宁新元古代冰碛岩的岩石地层学 ,以及碳、氧稳定同位素化学地层学的研究 ,证实了休宁新元古代地层存在两期冰川的记录 ,并通过与国内外同时代典型地层剖面的对比 ,认为休宁蓝田剖面的两层冰碛岩可能分别相当于 Sturtian冰期和 Marinoan冰期的沉积 ,其时代分别约为 710— 73 0 Ma,5 90— 60 0 Ma
Neoproterozoic glacial events have always been one of the hot topics in the study of the geology. Including China, there are generally one to two layers of moraine rocks commonly developed in many Neoproterozoic strata in many parts of the world. In some areas, three layers of moraine rocks can even be seen. Overlying the moraine rocks are carbonate cap rocks Cap Carbonate. Through the study of the lithostratigraphy of the Neoproterozoic moraine rocks and the stable carbon and oxygen isotopes in Xiuning, Anhui Province, it is proved that there are two records of glaciers in the Xixing Ancient Epoch of Xiuning. By comparing with the contemporaries at home and abroad The comparison of typical stratigraphic profiles shows that the two layers of moraine rocks in the Xiuning Lantian section may correspond to the sediments of the Sturtian and Marinoan glaciers, respectively, with ages of 710-730 Ma and 590- 60 Ma, respectively