深层砂岩储层可压裂性分析模型建立及应用

Establishing and applying the model of fracability evaluation for deep sandstone reservoirs

为提高海上深层砂岩储层改造效果,针对油藏埋深较深、测试产能低、储量落实程度低等问题,开展了砂岩可压裂性影响因素分析,重点基于脆性指数和断裂韧性建立了可压裂指数模型,并在现场进行了应用。研究结果表明:1)J油田储层杨氏模量约为(1.5~2.2)×10;MPa,泊松比为0.274~0.440,主要的约为0.270,岩石硬度总体适中,有利于裂缝的起裂。2)研究区归一化后的脆性指数为25%~45%,水平应力差异系数0.19~0.22,有利于压裂改造,具备形成复杂缝基础条件。3)基于J油田测井数据绘制了砂岩可压裂性指数图版,可压裂指数约为0.2~0.4;结合可压性分类标准在J-1井目标层共识别出4个优良压裂段,压后增油效果明显好于邻井压裂段。以上成果认识,对于海上深层砂岩储层压裂选层具有借鉴意义。

To improve the effect of fracturing stimulation in offshore deep sandstone reservoir on sea, for the current problem of reservoir buried depth, low test capacity and low degree of reserves implementation.Analyzing the influence factors of fracturing ability and establishing the model of fracability index by the mechanical brittleness index and fracture toughness, and it has been applied in the field.The results show that: 1)The mechanical experiment of oilfield J is about(1.5~2.2)×10;MPa, poisson ratio is about 0.274~0.440,the mainly is about 0.270,the hardness of the rock is generally moderate, which is beneficial to forming crack.2)Uniformization brittleness index is 25%~45%,low level difference coefficient is about 0.19~0.22,which has the basic conditions of forming complex fracture.3)The chart of fracability index is established based on log data of J oilfield, the fracability index is about 0.2~0.4, according to classification standard of fracability, four good fracturing layers is identified in well J-1,the effect of increasing oil is very well compared with other reservoir.The achievements and recognition can be used as a reference for the formation selection of offshore deep sandstone reservoir.