Evaluation Of Remaining Oil Potentialities And Study Of Redeveloping Measures For DLY Oilfield

DLY Oilfield which subordinates to the medium-low to ultra-low permeable oilfield hasentered into the high water-cut stage after more then ten years' development. At present seriousconflict between the layers, uneven production in the longitudinal reservoirs, serious waterflooded in the east-west, poor effect in the north-south wells in the plane, unclear cognitiontowards the distribution of remaining oil and poor effect of the infill wells seriously affects thestable yield target in the late stage. Recognizing the geological characteristics, deepening thedistribution of the remaining oil and exploring the development and adjustment mode which issuitable for DLY Oilfield are the key factors to secondary efficient development.A thorough division towards thin layers has been made by the method of "cyclecorrelation and graded control", and the original partitioning results of thin layers have beenverified again. The structure has been explained again by applying3-D seismic data, and twofaults have been found out in the new explanation. The micro structure of each sub-layer by hasbeen depicted using the real drilling data. The structure types can be divided into positive,negative, and cant micro structure. Through the study of extension of sedimentary facies andsand body, We can get the inclusion that the DLY Oilfield not only has the material sources ofHuai De in the southeast direction and Bao Kang in the southwest direction, but also has theTong Yu delta depositional from western and northwest. The proven geological reserve is1,900,600t calculated by volume method, and the reasons for this change are the decreasedeffective thickness and oil-bearing area. We have had a deep understanding of the geologicalcharacteristics and reserves of the oilfield.The distribution of remaining oil in the vertical and plane has been summarized throughthe research of numerical simulation. The major subzones G7,G10,F7,F8,F9are still the mainhorizons for the distribution of remaining oil, and the channel, microfacies in debouch bar andproduction well arrays are the enrichment areas for remaining oil. The encryption style of"second clip three" has been put forward on the basis of the original two encryption methodsand distribution of remaining oil. The recovery percent can be enhanced by3.5%in ten yearsby applying the numerical simulation to predict the encryption scheme. The best optimizedcyclic water flooding is the overall interval water injection, and the best water injection halfcycle is two months.22groups of profile control and water shutoff have been determinedthrough the fuzzy comprehensive evaluation method. The fracturing scale for water-oil wells indifferent styles of the square and inverted nine-spot pattern is that the corner well is about120m, and90m,90m,60m~90m for north-south well, east-west, water injection well, which isdetermined by the orthogonal design method. The DLY Oilfield will certainly march towardthe higher developing level through the comprehensive and potential tapping study.