A study of complex resistivity experiments and a saturation model of rock
MA Xuerui1,2, KE Shizhen1,2, HE Qiuli3, LI Junjian4, CAI Yalin1,2
1 College of Geophysics, China University of Petroleum-Beijing, Beijing 102249, China 2 State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum-Beijing, Beijing 102249, China 3 Technology Center, China Petroleum Logging Co. LTD, Xi’an 710077, China 4 Shanghai Petroleum Co .LTD, Shanghai 200041, China
Pure sands and shaly sands, with different clay contents, are made to investigate the effect of every factor of the rock resistivity dispersion characteristics. And the influences of porosity, water saturation, temperature, salinity, ion type and clay content are discussed. The Cole-Cole model is used to fit the resistivity dispersion curves of rocks and the zero-frequency resistivity and the relaxation time constant are inverted. It was found that the resistivity (at frequency of 1 kHz )and relaxation time constant of rocks exhibited a power law decreasing with the increase of porosity, water saturation, temperature, salinity and clay content.In the light of the experimental results, an interpretation model of complex resistivity spectral saturation was established by using the Cole-Cole model parameters and natural core data for verification.
Key words：
resistivity; dispersion; 1 kHz frequency resistivity; time constant; resistivity spectral saturation model
MA Xuerui, KE Shizhen, HE Qiuli, LI Junjian, CAI Yalin. A study of complex resistivity experiments and a saturation model of rock. Petroleum Science Bulletin, 2019, 02: 134-144.
