The Study On Reservoir Fine Anatomy Andremaining Oil

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 the principle of high-resolution sequence stratigraphy and sedimentary, and according to “the combination of source、hierarchical controlling、cycle comparison、considering of the fault” principle, I have made the fine division and correlation of substrata for Nanqidong test area of DaQing Sanan oil field, stablishing the sequence stratigraphic ramework of 390 wells of 9 time units. Basing on the different characteristic of sedimentary, I established the logging facies pattern of delta distributary plain、delta front(1 types of facies、3 types of subfacies、26 types of microfacies) which include the central bar、bradied channel、distributary channel、overbank sand、sheet sand microfacies and so on. And according to this, I drew the 9 plane sedimentary microfacies and made the research of the fine anatomy, summing up the distribution of sandbody in each time unit, determining that the layer of PI1-4 is the cycle which the sedimentary base level decreased quickly and slowly rised and the base level decreased to the lowest in the layer of PI2 c. On the basis of this, making the research of the effective sandstone thickness、permeability、variation coefficient of permeability、parameters of differential、interlayer and water flooding in the reservoir of the 4 main units. Therefore, making the full comprehensive understanding about the heterogeneity in the main oil layer. The types of remaining oil in Nanqidong test area of DaQing Sanan oil field are mainly the types that well-pattern can’t control 、the remaining oil in the upper thick sandbody、the remaining oil in edge of channel、the remaining oil in non-channel effective thin sand and the remaining oil in edge of fault which is the 5 types of remaining oil,providing a powerful guarantee for the further development of geology in this area.