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湖南上前寒武系分布广泛,地层发育齐全,沉积类型复杂,矿产资源丰富,是研究我国华南地区地质构造重要地区之一。本文叙述了上前寒武系的地层层序,进行了地层分区,将板溪群分为三个区,震旦系分为四个区,概述了各区地层特点。并提出了上前寒武纪的划分对比方案。对湖南晚前寒武纪的地史演化及沉积特征等,进行了初步探讨,认为冷家溪群属大洋环境优地槽型沉积,尔后洋盆扩张,地壳类型转化,板溪群既有冒地槽型又有优地槽型沉积;震旦系地壳稳定性增强,因此既有浅海碳酸盐台地沉积,又有海水相对较深的炭硅质盆地沉积,以及深海泥砂质复理石浊流沉积。总之随着时间的发展,陆壳自北西往南东增生,地槽往南东迁移。
The Upper Precambrian in Hunan is widely distributed, with well-developed strata, complex sedimentary types and rich mineral resources. It is one of the most important geological research areas in southern China. This paper describes the stratigraphic sequence of the Upper Precambrian, stratigraphic zoning, dividing Banxi Group into three zones, and Sinian into four zones, summarizing the stratigraphic features of each area. And put forward the comparison plan of Precambrian. Based on the study of the evolution and sedimentary features of the late Precambrian in Hunan Province, it is concluded that the Lengjiaxi Group is a favorable sedimentary environment in the ocean environment. Afterwards, the oceanic basin expanded and the crust type changed. Therefore, both the shallow marine carbonate platform sediments, there are relatively deep seawater sedimentary carbon-siliceous sediments, as well as deep-sea mud silt complex stoning turbidity Flow deposition. In short, with the development of time, the continental crust proliferates from northwest to southeast and the trough migrates to the south.