ES34；is the main oil—bearing zone in the Sanchunji area．Based on the core facies analysis of a single well and Stratigraphic classification and correlation by means of well logging da— ta，four sedimentary micro—facies have been distinguished as follows：SUbaqueous distribu— tary river course，interdistributary bay，river mouth bar and distal bar．The paper analvzes their distribution features and discusses the relation of the micro—facies with]ithologv， physical properties and oil of the reservoirs．