Characteristics of sedimentary facies of Xiamaling formation at Beizhangzi area,Kuancheng,Hebei

Xiamaling formation,Qingbaikou system in Upper Proterozoic at Beizhangzi area,Kuancheng,Hebei is a suit of clastic rock deposition with the main lithology as dark shale.The content and the assemblage of the oxide indicate the alternation of deposition environment.By analyzing the content alternation of the oxide,it is found that the values indicate a regular change of the sedimentary facies.Based on the study on field data of Xiamaling formation and the laboratory geochemical data,and on combinition with the research by predecessors,it is suggested that the sedimentary facies of Xiamaling formation at Beizhangzi area are composed of the barrier beach facies and the continental shelf facies, which can be further classified into two subfacies as the onshore facies and the offshore shelf facies,and three microfacies as foreshore zone facies,onshore zone facies and shale facies.And the sedimentary facies models of Xiamaling formation are summarized.