Fine Evaluation Of 4-5 Reservoir Of Badaowan Formation From 530 Well Area In Karamay Oilfield

Due to the near provenance,multi water system and rapidly changing sedimentary environment,the heterogeneity of conglomerate reservoir is serious.The micro pore structure presents complex mode distribution characteristics.The seepage system is mainly"non network thin network".Whether it is water flooding or chemical flooding,the fine evaluation of reservoir is the basis and premise of efficient reservoir development.After decades of waterflooding development in Xinjiang conglomerate reservoir,the main problems are high water cut,high recovery degree and low oil displacement efficiency.The implementation of tertiary oil recovery technology with chemical flooding as the replacement development mode has become the technical trend to improve oil recovery.The main purpose of fine reservoir evaluation is to construct sedimentary framework of formation,establish polymer flooding logging interpretation model and reservoir comprehensive evaluation method,clarify water flooding law and remaining oil distribution characteristics,and finally determine the comprehensive development potential of water flooding and polymer flooding in different layers,so as to provide geological basis and technical support for the overall design of development scheme.In this master’s thesis,the scientific research of more than two years has achieved totally the following achievements and understandings:（1）The comprehensive reservoir interpretation models based on sedimentary face control are established.In 530 well area,the formation b₄is sandy braided river deposition and the formation b₅is conglomerate braided river deposition,the different sedimentary micro-face controls the distribution of lithology,physical property,oil-bearing property,heterogeneity and reservoir type.The logging interpretation models established according to different area and different lithology improve greatly the accuracy of reservoir evaluation.（2）The formation mechanism of permeability anisotropy for conglomerate reservoir is revealed.The fast and changeable sedimentary environment of conglomerate reservoir lead to the great difference of permeability anisotropy,the research results show that the sedimentary face and hydrodynamic condition control the change law of permeability anisotropy of conglomerate reservoir,and the orientation arrangement of sediment particles and seepage path control the size of permeability anisotropy.（3）The influence of new water flooding on remaining oil distribution is determined.Through comprehensive analysis of oil production testing data,production profile and nuclear magnetic resonance logging,it is determined that the overall water flooding mode of reservoir J₁b_4-5 is rhythmic interactive water flooding（J₁b₄）,step-by-step water flooding(J₁b₅^1-1and J₁b₅^1-2)and vertical seepage water flooding(J₁b₅^1-3).Different water flooding mode controls the distribution characteristics of remaining oil for different layers.（4）The comprehensive development potential of water flooding and chemical flooding for different layer is determined.The following factors such as micro-displacement mechanism,water flooding law,remaining oil distribution characteristic,development status of production test well group and polymer flooding recovery experiment are analyzed comprehensively to determine the polymer flooding potential of reservoir J₁b_4-5in 530 well area.The research results show that the development potential of formation J₁b₄²and J₁b₅^1-1 is the best,followed by J₁b₄¹and J₁b₅^1-2 sandstone section,conglomerate section J₁b₅^1-2 has medium potential and formation J₁b₅^1-3has the smallest potential.Above research results have important guiding significance for the optimum production of reservoir J₁b_4-5 in combination of water flooding and chemical flooding,and provide geological basis for the design of polymer flooding program.Finally it has achieved remarkable social and economic benefits.