松辽盆地古龙页岩油储层孔隙结构对外来流体的敏感性  

Sensitivity of shale pore structure to external fluids for Gulong shale oil reservoir in Songliao Basin

作　　者：魏建光 付兰清[2,3] 赵国忠 李斌会[2,3] 赵小青 王安伦[1] WEI Jianguang;FU Lanqing;ZHAO Guozhong;LI Binhui;ZHAO Xiaoqing;WANG Anlun(Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development,Ministry of Education,Northeast Petroleum University,Daqing,163318,China;Exploration and Development Research Institute of PetroChina Daqing Oilfield Co Ltd,Daqing 163712,China;Heilongjiang Provincial Key Laboratory of Reservoir Physics&Fluid Mechanics in Porous Medium,Daqing 163712,China)

机构地区：[1]陆相页岩油气成藏及高效开发教育部重点实验室(东北石油大学),黑龙江大庆163318 [2]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [3]黑龙江省油层物理与渗流力学重点实验室,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2022年第3期120-129,共10页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家自然科学基金项目“考虑污染条件下页岩气储层气水两相渗流机理研究”(51474070);中国石油天然气股份有限公司重大科技专项“大庆古龙页岩油勘探开发理论与关键技术研究”(2021ZZ10)。

摘　　要：古龙页岩油储层压裂过程中将注入大规模外来流体,不同类型外来流体对页岩储层孔隙造成的伤害或改善需要定量评价。针对以上问题,基于二维核磁测试技术实现了页岩不同尺寸孔隙内的流体精确识别;建立了页岩不同尺寸孔隙对外来流体敏感性的定量评价方法;开展了古龙页岩岩心饱和不同类型外来流体前后的孔隙结构测试,定量评价了古龙页岩不同尺寸孔隙对外来流体的敏感性。结果表明:酸液对古龙页岩总孔隙度具有弱改善作用,其中对微孔有强改善,对小孔造成弱伤害;碱液对古龙页岩总孔隙度造成弱伤害,且随碱液强度的增加伤害程度先升高后降低,碱液对微孔弱改善,对小孔造成弱伤害;古龙页岩与中性滑溜水作用后微孔、小孔、中孔、大孔的孔隙度基本不变,孔隙结构对中性流体不敏感。研究成果对古龙页岩油储层压裂液体系配方设计具有重要指导意义。Large amount of external fluids are injected in Gulong shale oil reservoir during hydraulic fracturing process,thus it is necessary to quantitatively evaluate positive or negative effect of different external fluids on shale pore structure. In view of above problems,by utilizing 2D nuclear magnetic testing technology,accurate identification of fluids in different-sized pores in shale is achieved,and quantitative evaluation method for sensitivity of different-sized pores in shale to external fluids is developed. Test of pore structure of Gulong shale cores before and after saturated with different types of external fluids is carried out to quantitatively evaluate the sensitivity of differentsized pores in Gulong shale to external fluids. The results show that acid liquids slightly increase total porosity of shale,increase porosity of micropores in shale,and cause weak damage to porosity of small pores in shale. Alkaline liquids cause weak damage to total porosity of Gulong shale,and with the increase of alkalinity,the damage increases first and then decreases. Alkali liquids slightly increase porosity of micro-pores and have weak damage to small pores. After interaction with neutral slick water,the amount of nano-scale micropores,small pores,mesopores,macropores and total porosity of Gulong shale remains generally unchanged. This research has important guiding significance for fracturing fluid system design of Gulong shale oil reservoir.

关 键 词：古龙页岩 页岩孔隙结构 孔隙度测定 敏感性评价 核磁测试 

分 类 号：TE357[石油与天然气工程—油气田开发工程]