DISCUSSION ON AGE OF THE FENGTAI FORMATION ALONG SOUTHEASTERN MARGIN OF THE NORTH CHINA BLOCK
Cao Gaoshe1, Zhang Shanwen2, Liu Zhongquan2, Yang Xiaoyong3, Liu Deliang3
1. School of Resources and Environment, Henan Polytechnic University, Jiaozuo, Henan 454000; 2. Geological Scientific Research Institute of Shengli Oilfield, Dongying, Shandong 257015; 3. School of Earth and Space Sciences, China University of Science and Technology, Hefei 230026
There was an argument about age of the Fengtai Formation being Sinian or Cambrian. Based on the discovery of breakup uncomformity between the Lower Sinian Sidingshan Formation and the Fengtai Formation, the field features and geochemical evidence of the unconformity,and the Pb-Pb isochronal dating of silt mudstone interbeds from the Fengtai Formation being 620 Ma,the paper thought that the Fengtai Formation should be deposits of Late Sinian. This result might stimulate the study of paleostructure,paleogeography and paleontology in the transitional period between the Sinian and Cambrian in the North China Block.