METHODOLOGICAL FUNDAMENTALS OF THE EVALUATION OF POROSITY AND PERMEABILITY PROPERTIES OF PRODUCTION HORIZON WHEN USING HORIZONTAL WELLS

The relevance of the work. This paper provides a review of information on the structure and properties of oil reservoirs, on the conditions of concentration and filtration of oil in them. The use of horizontal wells, taking into account porosity and permeability properties of the reservoir, can significantly increase the contact area with an oil-saturated reservoir, ensure maximum development coverage and thereby reduce development time reducing the cost of oil production. Purpose of the work. The basic concepts of reservoir development and their application to horizontal wells in comparison with vertical wells are considered. Methods of research. A comparative analysis of the parameter of porosity and permeability properties of the production horizon, during the operation of its horizontal and vertical wells, is given. Results. The analysis of the skin zone influence on porosity and permeability properties of the reservoir. For a specific example, pressure losses were calculated for horizontal and vertical wells in order to conduct a comparative analysis of the wells under consideration. It is shown that for the same value of the positive skin factor, the pressure loss in the skin zone of a horizontal well is always less than its value in the vertical one. Horizontal wells can withstand a greater degree of damage than the vertical, without significant loss of flow rate. The analysis shows that a violation in the vicinity of the bottomhole zone, due to pore space bridging of the reservoir, leads to the formation of a zone with low permeability and additional pressure loss – the skin zone. Therefore, before making a decision on the impact on the bottomhole zone of a horizontal well, it is necessary to estimate the pressure drop in the skin zone and compare it with the total pressure drop between the reservoir and the bottom (the permeability of the skin zone with the reservoir permeability). Conclusions. For timely impact on the well bottomhole to improve the permeability of this zone and increase the ...