Remaining Oil Distribution And Countermeasures For Tapping Potential Of Ning 50 Complex Fault Block

It is very difficult to explore and develop low permeability reservoirs in complex fault block,the recovery factor of which is usually low at present,the development effect of which is poor,and the remaining oil distribution of which is complicated with great tap potential of reserves.Take Ning50 reservoir of Huabei Oilfield as typically special example,the paper focuses on main controlling factors and remaining oil distribution of low permeability reservoirs of complex fault block,recognizes underground features of this kind of reservoir,researches effective development methods and development countermeasures,and makes reasonable and scientific schemes for potential tapping to obtain higher recovery factor through comprehensive treatment,which have vital practical significance in improving the development level of hard-to-recover reserves of low permeability reservoir in complex fault block to realize the resource substitution.Based on the geological features of low permeability reservoir of complicated fault block,fine formation comparison and three-dimensional earthquake explanation,a fine structural model was created in consideration of production performance;based on upscaling geological model,the numerical simulation software was used for historical fitting;according to reservoir engineering techniques,dynamic analysis,and main factors of influencing the remaining oil distribution,the remaining oil distribution was quantitatively and qualitatively described;a rational measure was made according to the remaining oil distribution features;it was believed after comprehensive numerical simulation and reservoir engineering research that the remaining resources were mainly controlled by sand body,heterogeneity,and incomplete injection-production well pattern.The higher producing degree of main sand body led to more serious water flooding and lower producing degree of small sand body.Based on the remaining oil research,various research results and remaining source distribution,the plans for reservoir development were made to enhance the production capacity of wells.In addition to the former plan,three plans for reservoir development were designed.After index prediction,Plan 2 was recommended.In this plan,one new well was designed.According to the measures for old wells,it was expected that accumulative oil production increment would be 170,900 t in 10 years.This paper provided some theoretical guides for enhancement of oil recovery from reservoirs in the complicated fault block.