Abstract
Objectives of the study complex-upbuild carbonate reservoirs require the application of new technologies laboratory core examinations. The work presents the results of laboratory studies of the core Permo-Carboniferous deposits of the Usinsk oilfield. The Deposit is characterized by abnormal rheological properties of oil - high viscosity in the formation conditions and the presence of non-Newtonian properties. The geological structure of deposits complicated bioherm buildings and karst areas. High zonal and layered heterogeneity cause high heterogeneity of filtration properties of reservoir rocks. When typing such headers in reservoir properties have significant difficulties. Significant differences occur while such reservoir rocks are typified in reservoir properties.
According to the results of lithological-petrographic studies there are identified three main lithotype: limestone organogenic-detrital, limestone bioherm, Dolomites. The study of reservoir properties (porosity and permeability) carried out on plugs and full-size core samples diameter of 67, 100, and 110 mm. Absolute gas permeability is controlled by a wide range of parameters describing the structure of pore space. Accordingly, at equal values of absolute permeability, but at a different microstructure formation, the forming of various pore networks is possibly to wetting and nonwetting phases filtration.
core samples are the most informative for complex reservoir rocks studying. Experimental investigations have shown the presence of the scale effect in the study of the reservoir properties. It was established lateral anisotropy filtration properties together with the vertical anisotropy.
The scale effect will determine the usefulness of the study of filtration-capacitive characteristics of the samples and to increase the reliability of petrophysical basis for interpretation of geophysical research of wells. Experimental data on the anisotropic factors effect on the reservoir properties of the formation allow a better understanding of the disadvantages and improve methodologies build geological and hydrodynamic models of the deposits.