METHOD FOR DETERMINING THE TOTAL POROSITY OF NATURALLY SATURATED ROCK SAMPLES USING THE NMR METHOD Russian patent published in 2022 - IPC G01N24/08 

FIELD: total porosity coefficient determination.

SUBSTANCE: invention is intended to determine the coefficient of total porosity of naturally saturated core samples. The substance of the invention lies in the fact that naturally saturated core samples are taken from the core drilled using the insulating technology or waxed in the well, then the core samples are sent for examination by NMR at natural saturation, volumetric fluid saturation is determined by NMR, taking into account the correction for the hydrogen index (HI) fluids, the hydrogen index of fluids at natural saturation is calculated using a method based on determining the change in the volume of fluids that saturate the pore space of the test samples of a crushed sample by two methods before and after extraction, then the samples are sent to determine the porosity by the gas volumetric method in a naturally saturated state, which allows to determine the part of the pore space that is associated with the loss of light hydrocarbons during the rise of the core to the surface, the total porosity of the samples at natural saturation, determined by the complex method, is equal to the sum of the volumetric fluid saturation by NMR, taking into account the correction for the hydrogen index and the porosity determined by the gas volumetric method, after measurements of volumetric fluid saturation by NMR, the samples are placed under a fluid layer in the form of kerosene or hydrocarbons and kept under vacuum until the release of air bubbles ceases, then the samples are placed in a saturator, where they are kept for at least 2 hours with an overpressure of 15 MPa, then the determination is made coefficient of total porosity of samples by NMR method, additionally saturated with fluid, taking into account the correction for HI of fluids saturating the pore space.

EFFECT: providing the possibility of determining the coefficient of total porosity of naturally saturated core samples by a complex method based on the use of the NMR method and the gas volumetric method.

1 cl, 1 tbl, 3 dwg