Redivision and Correlation of Meso-Neoproterozoic Strata in the Jiangsu-Shandong-Anhui Area, Southern margin of North China Block

The Late Precambrian strata of Su-Lu-Wan(Jiangsu-Shandong-Anhui Provine) area is divided from lower to upper into the Huainan Group,Xuhuai Group and Suxian Group in Southern margin of North China Block. It is the Neoproterozoic Era in age. According to the stromatolites Linella-Gymnosolen-Katavia assemblage and present reported new U-Pb ages(SHRIPM), the Shijia Formation and Wangshan Formation of the upper part of the Xuhuai Group may be correlated with Xiamaling Formation with a weighted mean206Pb/U238of1368~1370 Ma in Yanshan Mountain area,northern China. Therefor, the Shijia Formation and Wangshan Formation is of Late Mesoproterozoic Era in age. The lower part of Xuhuai Group with the stromatolites ConophytonBaicalia assemblage may be correlated with Luda Group and Gezhenpu Group in Southern Liaodong Penisula, Liaoning Province, China. So, it is Early-Middle Mesoproterozoic in age. Further SHRIMP U-Pb dates of 976土24 Ma(206Pb/238U) and 1038 土 26 Ma(207Pb/206Pb) were gained from the diabase rock in the Neoproterozoic strata in the Xu-Huai area, which indicates the origin of the Neoproterozoic magma and it is also proved that there was a great scale basic magmatic active developed in the southeastern margin of the North China Block, which can be correlated with the intrusive magma events of the Grenvillian orogenic episode in Northern American,Mid-Africa and Easthern Greenland. So, Xuhuai Group and Suxian Group is the Neop-roterozoic Era in age in the southern margin of Northern China Block. Neoproterozoic strata is divided into Huainan Group of the lower part of Neoproterozoic and Nanhua System of the upper part of Neoproterozoic in Su-Lu-Wan district, southern margin of Northern China continent. Huainan Group is divided from lower to upper into Caodian(曹店) Formation, Bagongshan Formation, Liulaobei Formation, Shouxian Formation, Jiuliqiao Formation and Sidingshan Formation. It is of the early Neoproterozoic in age. Nanhua System is divided into Weigan Formation, Fengtai Formation and Wugangji Formation. Weigan Formation and Wugangji Formation are the normal marine facies deposit. Fengtai Formation is recognized as the tillite of Neoproterozoic glaciations. Weigan Formation, Fengtai Formation and Wugangji Formation can respectively correlate with Lantuo Formation,Gucheng Formation and Datangpo Formation in Yangze Block, South China. They are of the Late Neoproterozoic in age.