METHOD petrophysical studies of rock specimens LARGE DIAMETER FIELD

摘要

1. A method for NMR studies of full-size rock samples with large diameter natural saturation field, comprising placing a test sample in the coil, creating the magnetization caused by the magnetic moments of the hydrogen nuclei rock pore fluid by passing polarized current through the coil, the excitation of the free precession signal measured this magnetization in the Earth's magnetic field, the accumulation of the measurement results and the determination signal parameters, characterized in that, in order to increase the measurement accuracy, the optimum value is selected receiving frequency band from the condition ΔF≥2 / 0,14πT2min * where * T2min - the smallest value of the time constant of damping of the measured SP signals is performed digitally recording waveforms measured signals and perform processing information received in the frequency domain after optimal digital filtering, for each of the test sample accumulated signals rock pore fluid phase shift is carried out, leading to the initial phase of the signal from the first phase naka plivaemyh signals, the amount of phase shift is determined by measuring the phase and frequency of the signal from the additional coil placed in the sample and multiplying the perfluorinated oil phase shift signals from the perfluorinated oil at the ratio of the gyromagnetic ratios of the nuclei of hydrogen and fluorine. ! 2. A method for NMR studies of claim 1, characterized in that necessary to accumulate the number of repeat measurements is determined from a predetermined permissible relative error measurements measured and ε