The Research On Development Of Technical Policy Limits For The Thin And Poor Reservoir

Exploiting the thin oil-layer is an important step that we should take to increaseexploitable reserves and preserve steady production of Daqing oilfield. But on cause of thelow permeability, weak physical characteristic, high content of clay, large variation range oflithologic character, physical property, and the serious heterogeneity, it is always leading tothe phenomena, such as lower productivity well, faster decline of production, and formation’sinjection-production relation imbalance, which seriously affects exploitation in the oil-field.Therefore, the thin and poor quality pay zones technical policy limits of reasonabledevelopment is particularly important.Based on the thorough survey on performance data of secondary infilled well pattern inthis area of Daqing Oilfield, with the combination of theoretical method in reservoirengineering, numerical simulation and actual data, we research on the thin and poor qualitypay zones technical policy limits of reasonable development in the area. I have a study on theinjection and production pressure system with statistical method, and more accuratedetermination of the technical policy limits of the reasonable level of formation pressure,bottom hole flowing pressure and injection pressure. Through the contrast betweenconventional reservoir and thin and poor quality pay zones on different geological conditionsand physical properties, I have come to a conclusion on the method to determine themaximum well spacing considering the start-up pressure gradient of low permeability payzones. Applying the theory formula, we can get reasonable injection to producing well ratio,injection-production ratio and oil recovery rate through calculations. According to the resultsof reasonable injection-production ratio and oil recovery rate, geological reserves of thin andpoor quality pay zones in this area and oil wells perforated thickness, we can determinereasonable liquid production per unit thickness and water intake per unit thickness underdifferent water cut.