Quantitative characterization of pore structure of the CarboniferousePermian tight sandstone gas reservoirs in eastern Linqing depression by using NMR technique  

作　　者：Tao Fang Likuan Zhang Naigui Liu Liqiang Zhang Weimin Wang Lan Yu Chao Li Yuhong Lei 

机构地区：[1]School of Geosciences,China University of Petroleum,Shandong,266580,China [2]Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029,China [3]Key Laboratory of Petroleum Resources Research,Chinese Academy of Sciences,Beijing,100029,China [4]Institute of Quantum Electronics,School of Electronics Engineering and Computer Science,Peking University,Beijing,100871,China [5]Research Institute of Exploration and Development,Sinopec Shengli Oilfield Company,Shandong,257000,China

出　　处：《Petroleum Research》2018年第2期110-123,共14页石油研究（英文）

基　　金：The work was supported by the Natural Science Foundation of China(No.41372151);National Science and Technology Major Project of China(No.2017ZX05008-004);National Key Basic Research Program of China(973 Program)(2015CB250902).

摘　　要：Micro-nano scale pores can accurately and fastly be measured by the nuclear magnetic resonance(NMR)technique,which provides a new method to quantitatively characterize pore structures in tight sandstone.Based on the method of calibration of mercury pressure data for NMR T_(2) spectrum,for the measurement inaccuracy due to the mercury saturation less than 100%in tight sandstone,the mercury pressure curve and T_(2) spectrum is used to cumulate from the maximum pore on the right boundary to the small pores in the left,the range of pore-throat radius measured by the mercury injection in the leftward cumulative curve is selected as a comparable interval of NMR pore-throat radius,and the longitudinal interpolation method and the least square method are utilized to construct the distribution curve of pore-throat radius transformed by T_(2) spectrum.The modified method is used to obtain NMR T_(2) spectrum,conversion coefficient of pore-throat radius and pore-throat radius distribution of the Carboniferous-Permian tight sandstone gas reservoirs in the eastern Linqing depression,and characteristics of reservoir pore structures are quantitatively investigated;in addition,in combination with analysis of thin section and scanning electron microscopy,the reservoir effectiveness and cause of the pore structure variability in the tight sandstone are also well studied.The results show that the NMR pore-throat radius curve obtained by the modified method has a high consistency with the mercury injection curve,and the NMR test accuracy of tight sandstone is significantly improved.In the study area,the pore-throat radius of the Carboniferous-Permian tight sandstone mainly ranges from 0.002 to 2 mm,the pore is generally submicro-nano scale,but the pore-throat radius distribution of different types of sandstone varies significantly.The lithic quartz sandstone is rich in siliceous matter and poor in plastic detritus and matrix,generally dominated by submicro-scale pore-throats including micro-scale porethroats;lithic feldspar sandstone

关 键 词：NMR T_(2)spectrum Mercury injection Conversion coefficient Pore-throat Rock fabric MICROFACIES Tight sandstone Linqing depression 

分 类 号：P61[天文地球—矿床学]