摘要
针对江汉盆地潜江凹陷陆相页岩油岩心,结合应力敏感实验与核磁共振技术,定量给出应力敏感实验前、后岩心孔隙度变化,分析实验前、后岩心孔隙的变化规律,定量分析岩心孔隙变化对应力敏感的影响。研究表明:微米缝发育明显的岩心增加应力后,孔隙度减小幅度较大,微米缝部分闭合,孔喉减小,应力敏感性较强;应力降低后微米缝不能重新张开,渗透率不可恢复。基质岩心增加应力后,孔喉也有减小的现象,应力敏感性较高,但应力降低后岩心孔隙度恢复率较高,渗透率的恢复率也较高。泥质含量高的岩心,应力增加后孔喉减小的幅度大,应力敏感性较强,且应力降低后,岩心孔隙度恢复率低,渗透率不可恢复;泥质含量较低的岩心,应力增加后孔喉减小的幅度较小,应力降低后,岩心孔隙度恢复率较高,渗透率有一定程度的恢复。
In view of representative shale oil cores in Qianjiang sag,Jianghan basin,stress sensitivity test and nuclear magnetic resonance(NMR)technology are combined to give the changes of core porosity quantitatively and analyze the changes of pore distribution before and after stress sensitivity test,and analyze influence of core pore changes on stress sensitivity quantitatively.Results show that with increase of stress in core and obvious microfracture development,the porosity decreases greatly with the pore throat decreases,and the microfractures are partly closed,which causes the strong stress sensitivity.After the stress decreases,microfractures can not be reopened and permeability can not be restored.The pore throat also decreases with the increase of stress in matrix cores,and the stress sensitivity is higher.However,the recovery rate of core porosity and permeability is higher after the decrease of stress.For cores with high shale content,the pore throat decreases greatly and the stress sensitivity is strong when the stress increases,and the porosity recovery rate of cores is low and the permeability can not be restored after the stress decreases.For cores with low shale content,the pore throat decreases slightly with the increase of stress.After the decrease of stress,the porosity recovery rate of cores is higher and the permeability can be restored to a certain extent.
作者
李睿姗
李海波
杨正明
郭和坤
高铁宁
戴仪心
孟焕
LI Ruishan;LI Haibo;YANG Zhengming;GUO Hekun;GAO Tiening;DAI Yixin;MENG Huan(Research Institute of Exploration and Development,Sinopec Jianghan Oilfield Company,Wuhan 430223,China;Research Institute of Petroleum Exploration and Development,Langfang,Hebei 065007,China;Institute of Porous Flow and Fluid Mechanics,Chinese Academy of Sciences,Langfang,Hebei 065007,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100493,China)
出处
《中国科技论文》
CAS
北大核心
2019年第9期969-974,共6页
China Sciencepaper
基金
国家科技重大专项(2017ZX05049-005-004,2017ZX05013-001)
中国石油天然气股份有限公司重大科技专项(2017E-1514,2018E-11-05)
关键词
页岩油储层
江汉盆地
应力敏感
核磁共振
孔隙变化
微米缝
岩性
shale oil reservoir
Jianghan basin
stress sensitivity
nuclear magnetic resonance(NMR)
pore changes
microfracture
lithology
