Sedimentary Microfacies And Reservoir Characteristics Of The Upper Es2 Reserviors In Sheng-1 Area,Dongying Sag

Sheng-1 area has high quality oil-generating area and resourceful sedimentary source recharge.As a typical closed reservoir,its main oil fields in shengtuo area began to enter the development stage of high water-cut,high recovery percent and high oil recovery rate.Under the influence of development,it was more and more difficult.According to core observation,drilling data,thin section analysis,the physical property of the study region is good.But the oil-bearing property of reservoirs have large changes and strong heterogeneity.Based on the sedimentary theory,the paper combined core and thin section observation,logging,laboratory testing and production data to study the sedimentation characteristics,and reservoir characteristics of Es2 in Sheng-1 area,Dongying sag.Sediments in the research region are maily grey,green fine-grained sandstone and grey gritting material?siltstone?argillaceous siltstone,and dark grey and fuchsia mudstone.Because the sufficient clastic material supply from the north Chenjiazhuang uplift,large-scale braided river delta deposits have been developed in the study area during the sedimentary period of Es2.Braided channel microfacies and interchannel microfacies are the main factors.Erodsion surfaceare visible at the bottom of the channel,In the third and second sand set have stronge hydrodynamic force,and better channel development.In the first sand set,sedimentary environment is more complex,the channel is frequently oscillating,thickness increases,the upward sandstone appears big fluctuation,and the river channel swings frequently.Based on the above research,establish the sedimentary evolution model.Through the thin slice and the physical property data analysis,the main reservoir space are primary and secondary intergranular pore,secondary pores and micro-cracks such as intragranular dissolution pores and mold pores also developed.The physical property of the study region is good,and there are many different oily features in portrait mode.Comprehensive analysis of physical property data shows that there are many factors affecting the reservoir properties of the study area.Sedimentary aspects of reservoir rock particle size,miscellaneous content,sortability,and shale content and the strong cementation in diagenesis is the main controlling factor of the difference in oil content.Poor sorting and a large amount of miscellaneous radicals lead to local strong calcareous cementation,which is the main reason for the decrease of reservoir properties.Based on the study of reservoir heterogeneity control factors,combined with logging data,analysis of laboratory data and trial oil production data,the reservoir's “four-property” relationship was analyzed.Log evaluation of the reservoir in the study area,using the overlap chart method,the intersection diagram sends out a quicker and more intuitive identification of the oil layer,dry layer and water layer.Realize the identification and prediction of vertical oil-bearing intervals.