江苏油田低渗透油藏压裂效果影响因素研究

Study on influencing factors of fracturing effect in Jiangsu Oilfield low permeability reservoirs

为改善江苏油田低渗油藏开发效果,在明确低渗油藏压裂效果影响因素及评价方法的基础上,结合油藏数值模拟技术,对通过实施压裂改造的江苏低渗、特低渗油藏开展了压裂效果影响因素研究。分析和研究了油藏渗透率、有效厚度、含水率等参数对油井及水井压裂效果的影响规律。结合正交设计方法,明确了不同因素对压裂效果的影响程度。研究结果表明:对于实施压裂改造的江苏油田低渗油藏,当油藏渗透率低于20×10^(-3)μm^(2)时,油井压裂后能取得较好的增油效果,当油藏渗透率低于50×10^(-3)μm^(2)时,水井压裂后累积增注量增加比较明显。影响江苏低渗油藏压裂效果最显著的因素包括渗透率、裂缝方位、裂缝穿透比和裂缝导流能力;影响显著因素包括注采井距、有效厚度;不太显著的因素是含水率。

To improve the development effect of low-permeability reservoirs in Jiangsu Oilfield,based on clarifying the influencing factors and evaluation methods of the fracturing effect of low-permeability reservoirs,combined with reservoir numerical simulation technology,it has been carried out studies on the influencing factors of fracturing effect.This paper studied and analyzed the influence laws of reservoir permeability,effective thickness,water cut,and other parameters on the fracturing effect for oil-water wells.Furthermore,combined with the orthogonal design method,the influence degree of different factors on the fracturing effect was determined.The research results showed that for the low-permeability reservoirs in Jiangsu Oilfield undergoing fracturing,when the reservoir permeability is less than 20×10^(-3)μm^(2),the oil well can achieve a better oil increase after fracturing.When the reservoir permeability is less than 50×10^(-3)μm^(2),the cumulative injection increase after fracturing increases significantly.The most significant factors affecting the fracturing effect of low-permeability reservoirs include permeability,fracture orientation,fracture penetration ratio,and fracture conductivity;the significant factors include injection-production well spacing and effective thickness;the less significant factor is water cut.