基于核磁共振法的页岩纳米孔隙结构特征研究  

QUANTITATIVE ANALYSIS FOR NANOPORE STRUCTURE CHARACTERISTICS OF SHALES USING NMR AND NMR CRYOPOROMETRY

作　　者：李志清[1,2,3] 孙洋 胡瑞林 赵颖[5] 彭宇 LI Zhiqing;SUN Yang;HU Ruilin;ZHAO Ying;PENG Yu(Key Laboratory of Shale Gasand Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029;University of Chinese Academy of Sciences,Beijing 100049;Institutions of Earth Science,Chinese Academy of Sciences,Beijing 100029;School of Traffic and Transportation,Lanzhou Jiaotong University,Lanzhou 730070）（5.Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190）（6.Suzhou Niumag Analytical Instrument Corporation,Suzhou 215163)

机构地区：[1]中国科学院地质与地球物理研究所中国科学院页岩气与地质工程重点实验室,北京100029 [2]中国科学院大学,北京100049 [3]中国科学院地球科学研究院,北京100029 [4]兰州交通大学交通运输学院,兰州730070 [5]中国科学院力学研究所,北京100190 [6]苏州纽迈分析仪器股份有限公司,苏州215163

出　　处：《工程地质学报》2018年第3期758-766,共9页Journal of Engineering Geology

基　　金：中国科学院战略性先导科技专项(B类)(XDB10030100;XDB10030102);中国科学院青年创新促进会(2017092);中国科学院关键技术人才项目资助;国家自然科学基金(41672316)

摘　　要：选取威远海相页岩(1~#)、焦石坝海相页岩(2~#)、瑶曲凝灰岩(4~#)及瑶曲陆相页岩(5~#和6~#),采用场发射扫描电镜(FE-SEM)与低场核磁共振(NMR),研究中国海相页岩和陆相页岩之间的孔隙结构特征的差异化特征。核磁共振冻融法(NMRC)可以精细探测页岩的纳米范围的孔隙结构。该方法可以拓展到结合核磁共振弛豫分析进行微观测量,详细探测不同孔径尺度下页岩的孔隙结构。测试温度梯度变化越小,孔隙分布测量的结果越精细。测试结果表明,从样品5~#,2~#,6~#,1~#至样品4~#的孔隙率逐个减小。NMRC,LFNMR,压汞法(MIP),气体吸附法(GA)在它们各自的有效测量范围内,孔径分布表现出良好的一致性。因此,将NMRC,LFNMR与GA和MIP等方法组合,可以更准确地评估储层页岩的孔隙结构。研究结果表明,陆相页岩(5~#瑶曲页岩)的纳米孔隙更发育,与海相页岩相比也许具有更高的商业开发价值。Based on the differences in pore structure characteristics between marine and continental shale in China,Weiyuan marine shale（ 1^#）,Jiao Shiba marine shale（ 2^#）,Yaoqu tuff（ 4^#） and Yaoqu continental shale（ 5^#and 6^#） were selected to study the pore structure characteristics using cold field emission scanning microscopy（ FESEM） and nuclear magnetic resonance（ NMR）. Nuclear magnetic resonance cryoporometry（ NMRC） was employed to represent nano-scale pore structure. This method can be extended to microns measurement combining nuclear magnetic resonance relaxation analysis to detect in detail the pore structure of shales under the different aperture scales. The smaller the test temperature gradient is,the finer the result of pore distribution is. Test results show decreasing porosity from sample 5^#,2^#,6^#,and 1^#to sample 4^#. NMRC,low field nuclear magnetic resonance（ LFNMR）,m4ercury intrusion porosimetry（ MIP） and gas adsorption（ GA） methods show good agreement of pore size distribution in their respective scope of application. Hence,the pore structure of the reservoir shale can be evaluated more accurately by combining NMRC,LFNMR with GA and MIP. Thus the nano-pores of continental shale（ 5^#Yaoqu shale） are clearly better developed and will more likely have a higher commercial exploitation value than those of marine shale.

关 键 词：海相与陆相页岩 孔径分布 纳米孔隙 核磁共振冻融法 压汞法 气体吸附法 

分 类 号：P584[天文地球—岩石学]