Oil Logging Evaluation Of Continental Shale Oil In Block A

The continental shale oil reservoir in the study area not only has high clay content and complex pore structure,but also has well-developed laminae and foliation and strong anisotropy.The core analysis of laboratory is an important means to study the rock and fluid properties of shale oil and gas reservoirs.However,the shale’s core expands when it meets water and is fragile,so the experimental method for conventional sandstone is no longer applicable to shale core analysis.Therefore,laboratory rock physical analysis method for shale oil reservoir needs to be developed.At present,there is a lack of research on shale oil reservoir’s saturation model at home and abroad,especially in continental shale oil reservoir,so it is necessary to carry out this research.Shale reservoir saturation evaluation method,this paper adopted the method of electric and non-electric method two kinds of methods,from the rock physical property analysis of shale reservoirs,combined with the feature of continental shale reservoir in the study area of songliao basin,to carry out nuclear magnetic-rock itu,imaging measurement-mercury injection,shale electrical characteristics analysis and saturation model building method of research,The objective is to establish a suitable electrical method for shale saturation calculation in the study area.It use 2D nuclear magnetic resonance（2D NMR）for non-electrical method saturation calculation,and finally obtain the comparison of the evaluation results of the electric method and non-electric method shale oil reservoir saturation model.The main relaxation time of saturated water entering was determined through the change of NMR signal quantity of the magnetic T₂spectrum of dry sample-saturated water.The transformation from the time domain of NMR T₂spectrum to the space domain of pore path was carried out in combination with the high-pressure mercury injection experiment,so as to determine the main storage space range of continental shale oil reservoirs in Songliao Basin.Based on previous research results and the variation rules of 2D NMR spectra in different core experiment stages,the 2D NMR spectra were divided into regions,and the zoning criteria for 2D NMR spectra of shale in the study area were established.The method of self-imbibition and pressurized saturation was used to gradually increase the water saturation of the core,and the conductivity contribution of each zone was determined based on the changes of 2D NMR spectra of shale cores in each experimental stage,so as to build a shale conductivity model under laboratory conditions.When using conventional logging data shale saturation calculation,because the more in shale in the clay content in sandstone and high bound water content,shale skeleton of quartz,feldspar and other minerals are mud level,high clay content has been the formation of conductive network,so the clay bound water conductive network is continental shale oil the important reason for the low resistivity reservoir.Due to the influence of low permeability to ultra-low permeability,pyrite and kerogen content and other factors,the Simsimon model has fewer parameters and is easier to realize than other shale sandstone conductivity models.Therefore,the Simsimon model is used to calculate shale oil reservoir saturation by conventional logging in the study area.Through the experiment,the law of n value decrease with the increase of porosity,clay content increase,n value decrease.At the same time,it is also observed that the increase of kerogen content will increase the value of N,so the porosity,clay content and kerogen content of rock electrical parameter N of shale oil reservoir are optimized,and the saturation calculation accuracy of parameter N after optimization is significantly improved.In the calculation of shale saturation using CMR-NG logging data,a 2d NMR logging zoning interpretation template suitable for the study area was established based on 2d NMR zoning in the laboratory.By comparing the calculated results of each saturation model with the saturation of core analysis,it is concluded that the calculated results of simsimon degree model and 2D NMR logging saturation interpretation model after optimizing parameter N have achieved good results.