A new method for analysis of correlation nuclear magnetic relaxometry data in saturated cores is proposed. 2D maps of the joint distribution of characteristic correlation times and Van Vleck second moments, are calculated. Intramolecular contributions to the second moments for water and normal hydrocarbons were calculated. For this purpose, atomic structure designer program was developed. Intermolecular contribution to the second moment was assessed using the radial distribution function data obtained by X-ray diffraction analysis of liquids or calculated by the molecular dynamics method. The intramolecular and intermolecular contributions to Van Vleck second moment for water and n-alkanes were calculated for which the intermolecular contribution makes up to 10% of the intramolecular contribution to Van Vleck second moment. A new approach to the analysis of nuclear magnetic relaxation data in 2D maps of the joint distribution of nuclear magnetic relaxation times identifies dynamic phases for which the peaks are located on the diagonal of the map, and phases for which the nuclear magnetic relaxation times differ. For dynamic phases with equal nuclear magnetic relaxation times, the proposed approach suggests using the calculated second moment and calculating the corresponding correlation times, while for phases with different relaxation times, it is more informative to construct 2D maps of the joint distribution of correlation times vs Van Vleck second moments. Characteristic correlation times for water and n-alkanes were assessed based on ordinary nuclear magnetic relaxometry data. 2D maps of the joint distribution of nuclear magnetic relaxation times in core sample were analyzed, showing high mobility of water and deceleration of kerosene molecules in pore space of the rock. Opportunity for kerosene typing in core sample is demonstrated. For the first time, 2D maps of the joint distribution of Van Vleck second moments and correlation times have been obtained for oil-saturated sandstone. Van Vleck second moments obtained in the 2D map match the second moments calculated using the atomic structure designer program. Correlation time calculated in 2D map corresponds to significant deceleration of oil molecules in sandstone pore space under normal conditions. Contribution to nuclear magnetic relaxation due to paramagnetic centers in bulk solution was assessed. Cross plot of the second moment versus concentration of hematite Fe2+ ions and Cu2+ copper sulfate in water was constructed. Weight concentrations of salts at which the predominant contribution to nuclear magnetic relaxation will be from relaxation at paramagnetic centers have been determined.
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