The Reserch Of Logging Interpretation Methd Of Chang8Reservoir In Huanxian Oil District, Longdong Area

Chang8reservoir of LN area in Ordos basin is low permeability and porosity reservoir.In this area, the relationship of its log response and reservoir parameters os more complicated.In order to provide better service for the fine geological research of this area, this paperestablishes reservoir parameters modeling, and optimizes modeling. Thereby, theinterpretation effectiveness of Chang8reservoir is increased.In this paper, the research object is LN area, in Huanxian oil district, Longdong area, andthe target reservoir is Chang8reservoir of Yanchang formulation. Firstly, its geology isanalyzed. Secondly, based on the geological data, core data, logging data and dynamic data,stratigraphic division and correlation is studied, and its precise stratigraphic frame is built. Andthen, the research of four properties characteristics and four-property relationship is carried.Based on the analysis of four-property relationship, two interpretation methods of the studyarea, physics modeling of rock volume method and statistic method, are studied. And reservoirparameters interpretation modeling is established, including shale content, porosity,permeability and oil saturation interpretation modeling.Again, based on FORTRAN and C++software development platform, the software programming of reservoir parameters logginginterpretation modeling is developing. On the common Forward2.73software platform, everyinterpretation modeling is loaded, and the secondary interpretation of its exploratory wells iscarried out. The interpretation effectiveness is analyzed by collecting geological data, coredata and dynamic production data, and the interpretation modeling is improved. Finally, thesecondary interpretation of the existing log data is carried out by the established parameter loginterpretation modeling of Chang8reservoir, and the plane distribution characteristics ofreservoir parameters is depicted.The study shows that the target reservoir of the study area is low porosity andpermeability reservoir. Its porosity types are diverse, including intergranular pore, feldspardissolution holes, debris dissolved pore, intercrystalline pores, micro-cracks and other types.Among them, the content of the first three porosity types is the highest. And intergranular poreand feldspar dissolution hole is the main reservoir space. The property of different lithology isinhomogeneous, and its changing range is large. With the lithology becoming homogeneous,the reservoir property (porosity, permeability) improves. With the rock particles from coarse to fine, the permeability presents a declining curve, and the change of permeability is obviousbetween the pink and fine sandstone.Based on the research and optimization of interpretationmodeling, the shale content is calculated by GR logging response, and porosity is calculatedby AC logging response, and permeability is calculated by porosity, and oil saturation iscalculated by Archie’s formulas. After loading the program of reservoir parametersinterpretation modeling, the secondary interpretation of the exploratory well is carried out. Theinterpretation effectiveness and precision of the target reservoir is improved, and theinterpretation result is credible. Finally, the secondary interpretation of the exiting log data iscarried out. The distribution characteristic of reservoir parameters is depicted and the betterresearch result is achieved.