Methods Of Logging Evaluation Of Complex Reservoir In Lixian Slope

Due to the influence of lithology,petrophysical properties,pore structure and water property,the calculation of reservoir parameters is difficulty,the electronic response of the oil and water layer is complex and the precision of the productivity prediction is low.The research of logging evaluation in complex reservoir is of great importance for increasing exploration success ratio.Based on the analysis data of thin section,petrophysics experiments,logging data and production testing,four-property characteristics and relationship is carried out and the formation water salinity and crude oil properties is analysed further,which lay a foundation for parameter calculation,fluid identification and productivity prediction.In view of the complex physical property controlled by the mineral content,the multi minerals model is established and the porosity and the carbonate content is calculated by optimization method.The new permeability calculation method based on flow unit calibrated by NMR logging is established,which improves the calculation accuracy.The SSP is obtained by a series of environmental correction to SP logging.Then the formation water salinity is calculated,which solves the obsession caused by the changing formation water salinity.Based on the litho-electric experiments of different water salinity,the model of rock-electro parameters chntrolled by formation water salinity and carbonate content is established.Combining the NMR experiments,petrophysics experiments and the analysis data of thin section,the irreducible water saturation is calculated by the binary regression of the logarithmic flow unit index and the shale content.The inner mechanism of the logging response of complex oil and water layer is analysed and the induction factor is built to recognize oil layer.The oil-water layer and water layer is separated by the cross plot of indicator of fluid replacement method and apparent formation water resistivity.The cross plot of mobile water analysis based on the precise processing can identify oil-water layer accurately.The input parameters of pattern recognition are chosen by factor analysis of stepwise discriminant based on different logging conditions and the fluid identification can be carried out automatically.Water spectrum method of NMR logging can identify fluids without the influence of pore structure.The productivity prediction model is built for Diannan and Gaoyang area based on different physical property,viscosity and production.According to different physical property,the productivity is predicted by synthetic index method.According to different physical property and viscosity,the viscosity-varying capacity logging evaluation method is created based on two-phase flow theory.The method solves the influence of physical property,viscosity and production,which improves the precision of productivity prediction and provides a reference for oil resources evaluation and reasonable development plan.