The Research Of Sedimentary Microfacies And Barrier Beds Of The Upper S₂～(2+3) In The East Area Of Pucheng Oilfield

Combined with the abundant well logging data, this paper took the upper Es₂²⁺³ of the eastern Pucheng oilfield as the research target, and raised some new cognitions about the faults. According to the palaeogeographical condition and mass of core observation data, the target area is still treated as braided river delta sedimentary system. But the barrier beds delta sedimentary characters of the lower part of the 2 sand group and 3 sand group are more obvious than the upper of the 2 sand group. According to the analysis to the sedimentary cycle character and the flow units, the sedimentary microfacies of nineteen flow units of the 2+3 sand groups are researched by observing the drill core and combined with the bore logs. And it was divided into five microfacies: barrier beds microfacies, sand sheet microfacies, distal bar microfacies, braided channel microfacies, and mere microfacies.Based on the sedimentary microfacies research, and according to lithological observation and description, the lithological composition and thickness of the barrier beds which under the different environment are concluded, and analysis the barrier beds which is formed under the different conditions contributing factors, collecting the coherent analysis data of the inspection wells over the years, synthesize the drill cores analyze result of the barrier beds which is above-mentioned, researching the lithologic character, physical property, pore structure, and the microscopic heterogeneity of the barrier beds. Define the upper limit of the barrier beds, and according to electric logs to define the barrier bed that is composed by different lithological composition, the electrical property of the barrier beds, which is different lithological character, were generalized. On the base of the single sand which is subdivided by the oil layer, regard natural non-individual body of the barrier beds between single sand as a unit, apply electric logs to locate the thickness dates of the barrier beds which is different lithologic characters of the different well points. Get the actual distribution data, drawing the planimetric map and the profile map.According to the sedimentary microfacies and the distribution of the barrier beds of the target, then research the reservoir heterogeneity of the target.