黄沙坨油田火山岩裂缝油气藏储层评价

Reservoir evaluation of volcanic fractured oil and gas reservoir in Huangshatuo Oilfield

根据火山粗面岩的低渗透特点,从岩性特征、油层分布、孔隙、裂缝、孔道半径和相渗曲线等方面,揭示了开发生产中的间歇自喷和含水突进等现象,探讨了油藏埋深和油水界面的关系,建立了黄沙坨油田火山岩裂缝油气藏的储层评价指标。以压裂措施对裂缝宽度和渗透率的改善为依据,指出了改善流动系数,是中孔-低渗透油气藏,解决开发中、后期,压力和井温下降、油气比上升、产量递减、油层返吐压裂砂和渗透率降低等生产矛盾的有效途径。

Based on the low permeability features of volcanic trachyte, the phenomena of intermittent flow and water breakthrough are showed in the process of production from the aspects of the lithologic character, oil layer distribution, pores and fractures, pore radius and relative permeability curve. The relation between reservoir depth and oil/water contact is investigated and the reservoir evaluation indexes for volcanic fractured oil and gas reservoirs are established in Huangshatuo Oilfield. Relying on the principle that the fracturing stimulation can improve the fracture width and permeability, it is pointed out in the paper that the improvement of flow coefficient is an effective method to resolve the problems such as the decrease of pressure and well temperature, increase of gas-oil ratio, declining of production rate, production of fracture sand and decrease of permeability in the middle-late development stage of medium porous and low pearmeability oil and gas reservoir.