Study On Logging Lithofacies Identification And Interpretation Method In Upper West Section Of Gudong Seven Area

The heterogeneity of reservoirs in the upper part of the west section of Gudong seven area is strong,and the physical property difference of reservoirs in the same micro facies may be great.Gudong oilfield has entered the stage of ultra-high water cut.With continuous injection,the reservoir heterogeneity is stronger.High water flooding makes the difference of physical property of reservoir larger,and the error of interpretation of reservoir by conventional logging data is greater.The fluid properties of high water flooded reservoirs vary greatly,and it makes the prediction of residual oil saturation more difficult.This series of problems brings great challenges to production.The same lithofacies have certain similarity in sedimentary environment and in log response,and have similar physical characteristics on the reservoir.Therefore,interpretation and evaluation of reservoir can be restricted by lithofacies.Lithofacies constraint is achieved by classifying reservoir facies and similar logging facies and establishing interpretation model.At present,the research on the purpose layer of the upper part of the West Pavilion in Gudong seven area is mainly focused on the micro level.At high water cut stage,the water flooded extent of reservoirs in different locations of the same micro facies is quite different,and the difference of their flooding is mainly determined by their internal heterogeneity.Therefore,it is necessary to further classify the lithofacies of the microfacies in the upper part of the upper part of the west part of Gudong seven area,that is,the fine interpretation of lithofacies.In this paper,the core,logging and dynamic data of the upper section of the West Pavilion in the seven District of Gudong area are fully applied to analyze the characteristics of the physical property and logging response of different lithofacies on the core scale,and to establish the relationship between the lithofacies and logging responses.Under the condition of insufficient logging data,conventional lithofacies identification and interpretation methods have great limitations.Using the method of analyzing and combining of log response,pressing non lithofacies information,improving the lithofacies information and reconstructing the lithofacies indicator curve,the lithofacies identification can obtain better results and meet the precision requirements of constrained reservoir parameters interpretation modeling constraints.