皖南与湘西晚震旦世地层的划分与对比

<正> 中国南方晚震旦世地层,在斜坡—盆地相区,其上部有一套硅质岩,皖南称皮园村组,湘西及湘中称留茶坡组。长期以来,不少研究者都把这套硅质岩地层与灯影组对比,并以此来解释沉积环境及古地理。 笔者对浙西及皖南地区的晚震旦世地层进行了研究之后,曾对皮园村组的涵义作了修订,认为它仅相当于西峰寺组上段或灯影组上段(唐天福等,1981)。近几年来,笔者又

Division and correlation of the Late Sinian strata in southern Anhui and western Hunan

A sequence of the Late Sinian slope-basin facies strata characteristic of manganous dolos-tones-carbonaceous shales-phosphorites-carbonate rocks-carbonaceous or/and siliceous shales-cherts is wide-spreaded in southern Anhui and western Hunan. Generally based on the boundary between the carbon-aceous or/and siliceous shales and the cherts it is divided into two formations: the Lantian and Piyuanchung Formations in southern Anhui, and the "Duoshantuo" and Liuchapo Formations in western Hunan, which are respectively correlated with the Duos-hantuo Formation and the Tongying Formation on the Yangtze Platform. The authors have been studying the Upper Sinian strata of southern China during last decade, it is believed that the basal boundary of the Piyuan-chung Formation and the Liuchapo Formation should be set downward between the carbonate rocks and carbonaceous or/and siliceous shales, and they can be correlated only with the Upper Member of the Tongying Formation which is represent-ntative of a sequence from debris rocks to dolostones with banded cherts. Therefore, the Lantian Formation and the "Duoshantuo" Formation, of which the boundary has been corrected, correspond to the Duoshantuo Formation and the Lower Member of the Tongying Formation. In order not to confuse the "Duoshantuo" Formation at the slope-basin facies region with the Duoshantuo Formation, we propose that the "Duoshantuo" Formation be renamed the Louyixi Formation. From this conclusion, a new translation on the sedimentary history and paleoge-ography in Late Sinian should be got.