准噶尔盆地玛湖凹陷致密砂砾岩储层可动孔隙界限  

Movable pore limits of tight glutenite reservoir in Mahu Sag of Junggar Basin

作　　者：吴建邦 杨胜来 李强[1,2] 周伟[3] 赵彬彬 WU Jianbang;YANG Shenglai;LI Qiang;ZHOU Wei;ZHAO Binbin(State Key Laboratory of Petroleum Resources and Prospecting,Beijing 102249,China;MOE Key Laboratory of Petroleum Engineering,China University of Petroleum,Beijing 102249,China;Experimental Test Research Institute of Xinjiang Oilfield Company,Karamay 834000,China)

机构地区：[1]油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)石油工程教育部重点实验室,北京102249 [3]中国石油新疆油田公司实验检测研究院,新疆克拉玛依834000

出　　处：《大庆石油地质与开发》2022年第6期167-174,共8页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家重点基础研究发展(“973”)项目子课题“提高致密油储层采收率机理与方法研究”(2015CB250904)。

摘　　要：致密砂砾岩储层是一类重要的非常规油气储层,可动孔隙界限研究对其有效开发具有重要意义。选取典型样品进行在线核磁共振(NMR)驱替实验和CT扫描实验,并进行了数字图像相关(DIC)计算,研究不同岩相致密砂砾岩储层水驱和CO_(2)驱的可动孔隙界限,同时分析岩样水化诱导的介质变化对可动孔隙界限的影响机理。结果表明:牵引流砂砾岩、含砾粗砂岩、含砾细砂岩和重力流砂砾岩的水驱可动孔隙半径分别为0.43、0.40、0.22、0.14μm,CO_(2)驱可动孔隙半径分别为0.29、0.30、0.21、0.08μm;可动孔隙界限与渗透率呈线性正相关,CO_(2)驱可动孔隙界限明显低于水驱;致密砾岩储层水化诱导的介质变化对驱替动用有重要影响,一方面孔隙堵塞使可动孔隙半径升高,另一方面砾缘缝的形成可以充分发挥孔内渗吸作用,增加水驱采收率,但容易造成气窜,导致水驱后CO_(2)驱的可动孔隙界限降低不明显,增产效率降低。Tight glutenite reservoir is an important type of unconventional oil and gas resources,and study on mov‑able pore limits has significance for its effective development.Typical samples are selected for online nuclear mag‑netic resonance(NMR)displacement experiment and CT scanning experiment,and digital image correlation(DIC)calculations are performed.Movable pore limits of water flooding and CO_(2) flooding in different lithofacies tight glutenite reservoirs are studied,and influencing mechanisms of sample hydration induced media changes on movable pore limits are analyzed.The results show that water flooded movable pore limits of traction current gluten‑ite,gravel coarse sandstone,gravel fine sandstone and gravity flow glutenite are respectively 0.43,0.40,0.22 and 0.14μm,while CO_(2) flooded movable pore radius limits are respectively 0.29,0.30,0.21 and 0.08μm.Movable pore limits have linear positive correlations with permeabilities,and movable pore radius limits of CO_(2) flooding are sig‑nificantly lower than those of water flooding.Hydration induced media change has important influence on displacement and development of tight glutenite reservoir.On one hand,pore blockage increases movable pore radius,on the other hand,formation of gravel-edge fractures can give full play to imbibition in pores and enhance the water flooding recovery factor,but easy to form gas channeling and result in less reduction of movable pore limit and de‑crease of production increasing efficiency of CO_(2) flooding after water flooding.

关 键 词：致密砂砾岩 可动孔隙界限 水驱 CO_(2)驱 CT扫描 玛湖凹陷 

分 类 号：TE348[石油与天然气工程—油气田开发工程]