Heterogeneic Studying On Fuyu Oil Layer In Toutai Oilfield

At present,DaQing Oil Field has entered the later development period with high water cut,but there are still some remaining oil which is stored in underground reservoir.The sedimentary type of channel-delta are complex and it has serious heterogeneity which are the main factors influencing the distribution of remaining oil.To find out the distribution of remaining oil in underground reservoir,it needs to make fine anatomy of the reservoir in different environment and types.Applying for high resolution sequence stratigraphy and sedimentology principle,observing the principle of “Combining with the provenance,hierarchical control,cycle correlation,Considering fault”,I have divided and contrasted small layer of M10,M11 in total oilfield carefully.Stratigraphic strata has been founded which contains 392 wells and34 small layers.Based on different sedimentary microfacies,2 types of sedimentary facies inculding delta and meandering river,3 kinds of sedimentary microfacies including delta shunt plain,delta prophase subphase and meandering river subfacies,23 kinds of sedimentary microfacies were been found.Sedimentary microfacies including meandering river microfacies,distributary channel microfacies,overflow sand microfacies,sheet sand microfacies.34 plane sedimentary microfacies diagrams are plotted and described carefully.Distribution law of microfacies sand bodies was founded.According to the above research,and 34 small layers,s effective sandstone thickness,porosity,permeability,permeability variation coefficient,permeability breakthrough coefficient,flooded condition,reservoIr heterogeneity was understood.I discovered 3 types of remaining oil: marginal residual oil of river channel,residual oil remaining in differential reservoir,preferential migration pathway shielding residual oil.It is suggested that the remaining oil be exploited in the study area: development zone encryption,development zone expansion.