古龙页岩油复合压裂参数优化及应用

Optimization and application of composite fracturing parameters for Gulong Shale reservoir

针对古龙页岩油储层层理发育及裂缝扩展不均衡、缝高扩展受限的特点,通过开展岩石力学、地应力测试实验,明确储层裂缝扩展特征;在此基础上进行布缝优化、液性优选、经济导流能力构建,形成以“单簇改造最充分,单井改造体积最大化”为核心改造理念的复合压裂工艺。研究结果表明,采用压裂段内3~4簇、簇间距10~15m的布缝方式,可显著降低缝间干扰程度,促进裂缝均衡扩展,实现单簇充分改造;提高高黏冻胶压裂液比例至50%~80%,可实现储层改造体积最大化;结合不同尺度裂缝所需导流能力,提高大粒径支撑剂占比25%以上,可实现各级裂缝的有效支撑,保证长期稳产需求,对下一步试验井的高质量压裂改造具有十分重要的指导意义。

Due to the feature of developed bedding,uneven fracture growth and limited fracture height expansion in the Gulong Shale reservoir,the characteristics of fracture expansion in reservoir were determined through the experiments of rock mechanics and in-situ stress.On this basis,fracture layout optimization,fluid performance optimization,and economic conductivity construction were carried out,so as to form the composite fracturing technology taking“the most sufficient single-cluster stimulation and maximization volume stimulation in single well”as the core stimulation concept.The research results showed that the arrangement of 3~4-clusters in the interval and the spacing distance between clusters of 10~15 m could significantly reduce the interference between fractures,promote the balanced expansion of fractures,and realize the full stimulation of single cluster of fractures.Increasing the proportion of high-viscosity gel fracturing fluid to 50%~80%could maximize the volume stimulation of reservoir.By Combining with the required conductivity of different sized fractures,and increasing the proportion of proppant with large particle size over 25%,it could effectively support all kinds of fractures,and ensure long-term stable production,which has great guiding significance for the high quality fracturing stimulation of the test wells in the future.