THE PRECAMERIAN ON THE NORTHERN MARGIN OF THE SOUTH CHINA TERRANE （HUNAN PART）

By means of the structural analysis and multiple stratigraphic classification,the Precambrian on the northernmargin of the Hunan terrane（Hunan part ） is divided into the Qingbaikou’an （Neoproterozoic ） Dajiangbian Forma-tion and Sinian Sizhoushan,Tianzide,Zhengyuanling,Aiqiling and Dingyaohe formations ,and the following isotopicages of sedimentation have been determined :859～866 Ma for the Dajiangbian Formation,794 Ma for the Siz-houshan Formation and 718～721 Ma for the Aiqiling Formation.