ANALYSIS OF FACTORS, AFFECTING PRODUCTIVITY OF FRACTURED HORIZONTAL WELL IN TIGHT GAS FORMATIONS (A CASE STUDY OF RESERVOIRS IN WESTERN SICHUAN, CHINA)
Yakushev Vladimir S.1
1Gubkin Russian State University of Oil and Gas (National Research University
Keywords: tight formation, fractured horizontal well, factors, affecting well pro-ductivity
An analytical model was used to analyze the affect of factors on the productivity of fractured horizontal gas well in formations with permeability of about 0,1 mD. The following factors were considered: fracture width, fracture half-length, the number of fractures and fracture permeability. It was shown that unlike conventional low-permeability reservoirs, fracture permeability in tight formations has limited effect on the well productivity, whereas fracture half-length and the number of fractures are the main affect factors. It is noted that increasing fracture width thousands of times has no effect on the well productivity, and therefore, mesh simplification for numerical simulation of fractured horizontal wells in such formations was proved feasible.
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