FIELD: oil-and-gas industry; oil producing industry; search for oil fields and calculation of amount of oil in fluid filling pores, monitoring the development of oil fields, their flooding and determination of present oil saturation. SUBSTANCE: while determining macrosection of absorption of thermal neutrons in rock skeleton ((Σsk)) one establishes dependence between concentrations of natural radioactive elements and macrosection of absorption of thermal neutrons in rock skeleton, concentrations of natural radioactive elements in shaft of borehole are determined by method of spectrometric gamma logging and values of Σsk corresponding to obtained values of concentrations are calculated by dependences prepared in advance. For preparation of dependences between values of concentrations of natural radioactive elements and macrosection of absorption of thermal neutrons in rock skeleton collection of cores from interesting deposits can be selected and measurements of these values can be conducted on the same samples. Dependences between macrosection of absorption of thermal neutrons of rock skeleton and values of concentrations of natural radioactive elements for examined deposits obtained at least in one borehole can be applied to deposit as a whole. EFFECT: higher efficiency. 3 cl, 5 dwg, 2 tbl
