Research On Interpretation Criteria For Effective Thickness Of CO₂ Displacemen In Bei 14 Block Of Hailar Basin

The Hailaer Basin is located in the Inner Mongolia Autonomous Region,and the Bay 14Block in the Research Area is located in the middle of the Beier Sag Oilfield in the Hailaer Basin.According to the proven reserves submitted by Hailar Oilfield,the Bayi 14 area is rich in oil and gas reserves,but because the block belongs to low-permeability and ultra-low permeability reservoirs,the yield of water injection is low and the development effect is not good.Especially for low-permeability tuffaceous reservoirs,after using fracturing technology,the effect of water wells is not obvious,and the recovery rate is low.In order to solve the problem of oil recovery,a CO₂ pioneer experiment was carried out in the ultra-low-permeability Xing'anling oil layer in the Hailaerbei 14 test area.Because CO2 gas injection can effectively improve oil recovery,the effective thickness standard has changed,and the logging physical property and electrical standards established in the reservoir evaluation stage cannot fully adapt to the CO₂ flood reservoir interpretation.The purpose of this paper is to adapt to CO₂ gas injection,and it is necessary to interpret the effective thickness standard of CO₂ flooding to determine the effective thickness physical property standard and electrical standard of CO₂ flooding.In the process of studying the effective thickness standard,the theory of oil core geology,petroleum geology,structural geology,mathematical statistics analysis and well logging is combined with oilfield core description,physical property analysis and oil testing.And methods,and carry out CO₂ flooding laboratory experiments to comprehensively determine the effective thickness standard for CO₂ flooding.According to the above data and research methods,the following results have been achieved:lithology,physical properties,oil-bearing properties and electrical properties have a relatively consistent relationship,and the“four-sex”relationship is good;the reservoir physical parameters are established,porosity,permeability and saturation.Degree parameter interpretation model;using the minimum throat radius method,indoor displacement experiment and other methods to determine the effective thickness physical property standard of CO₂ flooding;based on the four-study study and the lower limit of physical properties,according to some non-coring data of Bay 14 area,Porosity and deep lateral resistivity are preferred,the CO₂ effective thickness electrical standard is determined,and an effective logging interpretation method is established on the region.