Study On Optimized Development Of Low Permeability And Thick Oil Layer Reservoirs In The Yanchang Formation In The Hancha Area Of The Ordos Basin

The development of low permeability reservoirs accounts for a large proportion of China's reservoir development.The development of low-permeability reservoirs has to overcome more problems than the development of general sandstone reservoirs,including low permeability,small porosity and complex structure,large coefficient of variation within the layer,rapid decline in production,and low recovery.And many more.In the actual reservoir survey,it is found that some reservoirs not only have the characteristics of low permeability but also the thick reservoir.Therefore,in the development process,not only the problem of low permeability but also the development of thick oil layers will be encountered.The in-layer heterogeneity,the influence of the interlayer,and the ineffective water circulation.And once the reservoir has two characteristics of low permeability and thick oil layer,it will further develop new development problems.This paper takes the low-permeability and thick oil reservoirs of the Yanchang Formation in the Hancha area of the Ordos Basin as an example,collects the data of the study area,investigates relevant literatures,and builds relevant theoretical models.The main research is as follows:(1)Determine the geographical location of the study area by analyzing the relevant geological data of the study area,then divide the stratum and analyze its structural features,sediment types and sand body distribution,and finally the physical properties,pore types and heterogeneity of the reservoir.Sex,sensitivity,voltage stabilization system,and seepage characteristics are determined;(2)Analyze the current development status according to the dynamic data of the study area,and analyze the characteristics of the liquid production,the effect of water injection development and the water seeing characteristics of the water well in the existing development mode of the study area,so as to obtain low permeability Development characteristics of oil reservoirs;(3)Carry out numerical simulation research on the study area,fit the historical production situation of the study area,and analyze the decline of formation pressure,the distribution of oil saturation and the distribution of remaining oil in different areas of the study area at present,for further potential tapping or improvement.Provide a basis for production status.(4)According to the geological and development conditions of the study area,the theoretical model is established to analyze the influence of different rhythms,interlayer position,perforation position,water injection intensity and crack occurrence,and how it affects the development of low permeability and thick reservoirs.To analyze how the low permeability oil reservoir can adjust the mining mode when one or several factors are present at the same time.Conduct comprehensive consideration and analysis on the above research,establish a theoretical model for related research,and propose reasonable development strategies for low permeability and thick oil reservoirs.Optimized selection of development layer system,reasonable well pattern density,reasonable well spacing and injection-production pressure system,and finally obtained a reasonable development method optimization study for low-permeability thick-oil reservoirs.