METHOD FOR DIFFERENTIATION OF POROUSNESS OF HETEROGENEOUS CARBONATE FORMATIONS Russian patent published in 2022 - IPC E21B47/00 E21B49/00 G01V5/14 

FIELD: petroleum geology.

SUBSTANCE: invention relates to the field of petroleum geology and can be used to determine and differentiate the voidness of carbonate reservoirs. According to the method for differentiating the porosity of heterogeneous carbonate formations, reservoir intervals are identified using the methods of gamma ray logging (GRL) and neutron-neutron logging on thermal neutrons (NNL-t) with subsequent calculation of the values ​​of the difference measurement parameters ΔI_grl and ΔI_nnl. At the same time, the refinement of the structure of lithotypes, which, according to well logging data, are considered homogeneous, is carried out by making cubic rock samples with sides of 40±1.0 mm, on which tomographic studies are carried out and open porosity (C_p) is calculated using the Preobrazhensky liquid method. The open porosity of a homogeneous sample is presented as the sum of the porosities of its permeable and dense parts. According to the X-ray tomography method, the proportion of permeable reservoirs D_perm is estimated. Knowing for the core sample C_p by the liquid method and taking for the dense part C_p = C_pLID-PL, the open porosity of the permeable part is estimated by the formula. C_Pperm = (C_pLID-PL-ND - C_pLID-PL * (1- D_perm))/D_perm.

EFFECT: increasing the detail and reliability of determining effective oil-saturated thicknesses that make up heterogeneous carbonate reservoirs by combining methods of radioactive logging and core X-ray tomography.

1 cl, 3 dwg