Analysis of medium to high permeability reservoir heterogeneity based on subdivided zone in Albert basin

K oilfield of southern Albert belongs to a medium to high permeability reservoir and has a strong heterogeneity.By mainly using 37 m cores and slice,granularity,scanning electron microscopy(sem),X-ray diffraction,mercury injection of 280 samples,as well as the testing results of physical properties,the heterogeneity analysis on reservoir layer,interlayer and the microcosmic reservoirs and its controlling factors have been carried out.The study found that the reservoir permeability variation coefficient is 0.83~1.81.The strong heterogeneity,clay and the difference between various types of carbonate rock,combined with the sedimentary particle grade change,are the main influencing factors of reservoir heterogeneity.On the basis of this,the rocks from Zone1 A,Zone1B and Zone1 C are mainly divided into coarse- grain of grain in the cladding type argillaceous cementation sandstone,fine- grain in carbonate cementation sandstone pore type and package- coarse particles of shell type and argillaceous cementation sandstone pore type.