Sedimentary facies of the first member of the Kongdian Formation in the Zaoyuan Oil Field had been studied￡it is believed that it belongs to alluvial fan facies￡According to the results of detailed observations of the cores￡?combined with other facies lndicators￡?it iS held that the alluvial fan?afan delta system is formed by the entrance of the alluvial fan in?a tO a lake basin￡The main lines of evidence are sedimentary indicators generated by conti?a nental and subaqueous environments￡?tractive and gravity current￡?flows and waves￡?nor?a real and event origins￡The fan delta can be aubdivided?¤into three subfacies￡ofan--delta plain￡fan?adelta front and pro--fan delta￡Lacustrine facies deposits are relatively salient￡? involving overhank lake and salt lake deposits￡The construction of a sedimentation model is an important basis for studying the reservoir heterogeneity and reservoir geologic con?a ceptual model and describing and characterizing the reservoir