The Study On Remaining Oil Distributions And Development Strategies Of High Water-cut Reservoir In Complicated Small Faulted Block

The essential features of complicated small block reservoir of Jiang Su oilfield are many faults, complex structure, small oil-bearing area and complicated oil-water relationship. Influenced by geological, development conditions and many other factors during the high water-cut period, the remaining oil distributed even more scattered. Therefore, to enhance the recovery rate, it is very important to develop a series of remaining oil study methods adapting to Jiangsu high water-cut small faulted block reservoir. In the long term, it will generate great economic benefits.According to the geological features and current development status of Jiangsu complicated small faulted block reservoir, we selected five representative high water-cut oilfields,which are Zhen Wu, Zhou Zhuang, Song Jiaduo, An Feng, Fan Zhuang, as the samples of the project research and field experiments. Through further subdividing flow unit, rebuilding the geological model, and main methods such as reservoir numerical simulation, remaining oil monitoring means, dynamic performance analysis, we studied waterflooded mechanism and characteristic, and the distribution rule of remaining oil during high water-cut period from different aspects, with a variety of methods. Research indicates that remaining oil saturation and remaining reserves are dominated by sediment facies belt, improved well patterns degree and fault shelter. The remaining oil distributes mainly in well to well area in high places near fault for narrow oil-bearing zone and active edge-bottom water reservoir such as Zhou Zhuang, Song Jiaduo and Anfeng oilfields, the technique of a complex construction well is becoming economic practical effective way of enhancing the recovery of such blocks. For bedded sandstone reservoir of Fan Zhuang oilfield, well pattern thickening has been mainly carried out in the top area of the structure. For Zhen Wu oilfield with muitiple reservior types coexisting, because of geological conditions, long-term frequent adjustment measures owing to pressure of production rate, development characteristics of complex small faulted block caused a variety of origin of the remaining oil distribution, the current status of development is not to form a dominant macro-distribution feature of the remaining oil. The application of hydrodynamic force methods and complex construction well technology improved the oilfield development effect effectively.