页岩储层渗透率数学表征  

Mathematical characterization of permeability in shale reservoirs

作　　者：糜利栋 姜汉桥[1] 李俊键[1] 田野[1] 

机构地区：[1]中国石油大学石油工程教育部重点实验室,北京102249

出　　处：《石油学报》2014年第5期928-934,共7页Acta Petrolei Sinica

基　　金：国家重点基础研究发展计划(973)项目(2013CB228005)资助

摘　　要：为研究页岩储层渗透率表征方法中存在的问题,根据页岩储层独特的裂缝、孔隙分布特点,分别建立了裂缝渗透率理论计算模型和基质渗透率理论计算模型,定性分析了缝宽、孔隙直径、孔隙压力等参数对渗透率的影响。模型研究表明:裂缝内气体渗流满足立方定律,其渗流能力由缝宽决定;基质渗透率受气体滑脱效应和扩散效应影响,其渗流能力由孔隙压力和孔隙直径共同决定,且随孔隙压力和孔隙直径的变化发生动态变化;裂缝渗透率和基质渗透率极差较大,实际应用时须进行适当分类处理,以克服采用现有渗透率数学表征方法表征页岩气渗透率的不足。应用实例结果表明,该方法准确有效。To investigate the deficiencies in methods for permeability characterization of shale reservoirs, fracture and matrix permeability calculation models are respectively established according to unique characteristics of fracture and pore distribution in shale reservoirs. Further, influences of fracture width, pore diameter and pore pressure on permeability of shale reservoirs are qualitatively analyzed. Results show that： （1）Gas flow in rock fracture complies with the ＂cubic law＂, with flow ability in porous media determined by fracture width. （2）Matrix permeability is affected by gas slippage and diffusion effects, with flow ability in porous media jointly determined by pore pressure and diameter ; flow agility in porous media dynamically changes with variations in pore pressure and diameter. （3） Because the range of fracture permeability and matrix permeability is enormous, proper classification processing is needed in practical applications, so as to overcome the defects of using existing mathematical methods for characterization of shale gas permeability. The results of an example analysis verify the validity of the proposed method.

关 键 词：裂缝渗透率 扩散效应 气体滑脱效应 基质表观渗透率 数学表征 

分 类 号：TE312[石油与天然气工程—油气田开发工程]