Experimental Study On Fluid Occurrence And Mobility Of Chang 7tight Oil Reservoir

The pore structure and fluid mobility are very important for predicting the production capacity of tight oil reservoirs.In the thesis,physical property parameters measurement,including scanning electron microscopy,high pressure mercury injection and constant velocity mercury injection experiments were carried out on the core of tight oil reservoir in Chang 7 section of Ordos Basin.The relationship between physical property parameters and pore throat structure parameters was analyzed to evaluate fluid mobility.The results show that the pore throat radius of tight reservoir is smaller than that of conventional reservoir,and the relationship between porosity and permeability is similar to that of conventional reservoir,but the relationship between pore structure parameters and porosity in tight reservoirs is poor,so porosity cannot be regarded as one of the main parameters for evaluating tight reservoirs.The experimental observation of fluid mobility by combining NMR experiment and centrifugal experiment shows that the relationship between water saturation and permeability is good,which is independent of the type of T₂spectrum peak.The nuclear magnetic resonance T₂spectrum was converted into the aperture distribution by interpolation method,and the power function relationship between T₂and the radius r of the pore throat was established,indicating that T₂has a good correlation with the radius of the pore throat.