Scaling of NMR and Mercury Porosimetry Data on the Basis of Reservoir Parameters of Various Rocks

Investigations aimed to calibration on Nuclear Magnetic Resonance (NMR)measurements and Mercury Porosimetry (MP) were performed on a big group of samples of various rocks. Measurements of the T2 relaxation time were done for hydrogen nuclei occurred in the media in pore space of rocks, in the bound water in clay minerals and in the hydroxyl groups in these minerals. Cumulative NMR signals were calculated and used for qualitative description of the porous space in rocks. Mercury porosimetry measurements were also done to obtain cumulative intrusion and cumulative pore area plots vs. pore diameter and incremental intrusion and incremental pore area vs. pore diameter. The results of both methods were correlated to find the corresponding anomalies for the scaling of the NMR outcomes T2 in the pore diameter and fracture widths D. The correlation equations for T2 and D were calculated for the full data file. The result equations were tested for the extreme values of diameter in the mercury porosimeter range. Results proved the significant role of micropores and microfractures in the porous space of the carbonate rocks examined and showed the big diversification of results for the Carboniferous and the Devonian carbonates.