METHOD FOR DETERMINING AN OIL-AND-GAS SATURATION INDEX BY A GEOPHYSICAL WELL-INVESTIGATION SYSTEM ON THE BASIS OF PULSED NEUTRON LOGGING METHODS

摘要

The proposed method can be used in geophysics. The method consists in carrying out measurements by a pulsed neutron logging method and calculating a macroscopic section of thermal neutron absorption in the rock, and determining the macro-component composition of rocks, including porosity, by a geophysical well-investigation system, wherein, in order to calculate the macroscopic section of thermal neutron absorption by stratum water and hydrocarbons, use is made of the elemental composition and density thereof, and the hydrocarbon saturation is calculated in relation to gas (formula I) and to oil (formula II). In order to calculate the macroscopic sections of thermal neutron absorption by macro-components forming a solid rock phase, a collection of core samples from exploratory wells is additionally prepared, and the mineral and elemental composition of the samples and sample weight loss upon heating are measured in said collection, a mineral-component rock model is formed and macroscopic sections of thermal neutron absorption for each macro-component forming the solid rock phase are calculated. The invention increases the accuracy of determining the hydrocarbon content.