The Application Of Using Nuclear Magnetic Resonance Logging To Evaluate The Pore Throat Structure In The Tight Oil

This thesis relying on the application of nuclear magnetic logging mechanism study in the tight oil reservoir and the well logging evaluation of the tight oil in Jimusar Sag,and the research object is the tight oil reservoir of Lucaogou jimusar sag in Zhunger basin.The target reservoir porosity in the majority of nanoscale,with high residual oil saturation,and the wettability of reservoir rocks show neuter relative and oil wetting,so that the applicability of existing porosity evaluation model is poor.Through analysis of fluid distribution,microscopic wetting and fluid relaxation properties in the tight oil reservoir,we believe that the tight oil reservoir have a characteristic of the small pore full of water and water wetting,and the big pore full of oil and oil wetting.On this basis,found out a new method to evaluate the pore structure in the tight oil reservoir.On the basis of the distribution of pore diameter evaluated by the nuclear magnetic resonance T2 spectrum,and the data of hydrophilic surface relaxation rate and the oil surface relaxation rate,using different conversion factor to transform the oil spectrum and the water spectrum to the oil aperture and the water aperture respectively,so both combined can get the total pore aperture distribution.The actual log data processing results and core mercury injection experiment data analysis results are consistent,so we believe this method is validity and reliability.