For the first time in geophysical practice the study of a geological structure was performed with continuous and contactless thermal profiling on full-size cores. 3104 cores of carbonate rocks of low-Permian and mid-Carboniferous deposits of Usinsk oilfield from two wells over 307 m and 134 m depth intervals were studied. For every core sample the profiles of thermal conductivity and volumetric heat capacity were recorded with resolution about 5 mm. Thermal anisotropy coefficient and thermal heterogeneity coefficient of each sample were determined. Zonality of rock properties was assigned with analysis of full set of thermal properties. Interconnections of variations of thermal conductivity, volume heat capacity and thermal heterogeneity coefficient with logging data on porosity and oil saturation were established. It allowed to differentiate porosity types within studied depth intervals, to specify porosity variations at different scales (from the first centimeters to several tens meters), to specify zones with different oil saturation, to assign zones with variations of mineral structure and rock macroanisotropy. The solution of inverse problem performing at analysis of joint thermal profiling data and logging data allowed to establish reservoir zonality using dependence of thermal conductivity on the ratio of oil and reservoir water in a pore fluid.