FIELD: measurement.
SUBSTANCE: invention relates to methods and systems for determination of density of parent rock or grains of rock of subsurface formation. They include measurement of weight in air of fluid-saturated sample of subsurface formation, wherein the mass in the air includes the sample weight, the weight of the fluid surrounding the sample, and the fluid mass inside the sample. Volume of fluid inside sample, Vf, and volume of fluid surrounding sample, Vsur, are determined by means of nuclear magnetic resonance (NMR). Sample can then be immersed into a pre-determined volume of the weighing fluid, and the weight of the fluid-saturated sample in the weighing fluid, mf, is measured. Using measured and determined values it is possible to determine volume of sample, Vc, volume density of sample, ρb, volume of parent rock, Vm and density of parent rock and grains of rock of subsurface formation, ρm.
EFFECT: disclosed is a method for determining rock density.
15 cl, 12 dwg
