Abstract：Both NMR TZ spectra of core and mercury intrusion capillary pressure can be used to characterize pore throat structures of rock in some degree. Theoretical analysis reveals correlation between these two sets of data. Determining the transferring coefficient between TZ and P} is the key step when NMR spectra are utilized to study rock pore throat structure. In earlier methods,some characteristic parameters of rock should be given in advance before transferring TZ into P},which is difficult to determine these parameters precisely in practice. By using directly correlation between NMR spectra and mercury intrusion capillary pressure,a new method is presented in this paper to determine the transferring coefficient objectively. As a result,all the difficulties determining rock parameters are avoided. With this new method,after comparison and analysis of calculated various NMR spectra in 6 rocks,NMR (Nuclear Magnetic Resonance is called NMR for short)capillary pressure curve and pore throat distribution are given, and the results are compared with the analysis of mercury intrusion capillary pressure. Our research shows that NMR TZ spectrum of core holds a little predominance in practical application and evaluation precision. In saturated oil rock,NMR spectra of core can be still utilized to evaluate the distributions of pure throat,the relaxation character of oil-gas exists as an influence background value, which may have limited effects on the evaluation results.The transforming coefficients of the samples,ranging 2500~4000 X MPa are given in the paper.
刘堂宴, 王绍民, 傅容珊, 周明顺, 李艳华, 罗曼. 核磁共振谱的岩石孔喉结构分析[J]. 石油地球物理勘探, 2003, 38(3): 328-333.
Liu Tangyan, Wang Shaomin, Fu Rongshan, Zhou mingshun, Li Yanhua, Luo Man. Analysis of rock pore throat structure with NMR spectra. OGP, 2003, 38(3): 328-333.
