In this paper, array acoustic data of tight sandstone gas reservoirs are analyzed, and the methods of curve overlapping about ratio of P-wave velocity to S-wave velocity with acoustic time curve, Poisson′s ratio and bulk modulus curve are optimized to qualitatively evaluate the gas-bearing properties of tight sandstone gas reservoirs; core sample testing experiments are carried out, and the method of quantitative calculation of gas saturation by array acoustic data is discussed. The results show that the two curve overlap methods comprehensively consider the changes of reservoir physical properties and gas-bearing properties, and are effective combinations for evaluating gas-bearing properties of tight sandstone reservoirs. They can represent array acoustic data to evaluate gas-bearing properties of tight sandstone reservoirs. The gas saturation calculated by using ratio of P-wave velocity to S-wave velocity is higher than the actual measured value. The gas saturation calculated by using bulk modulus is lower than the actual measured value. However, the average value of the two methods can better reflect the gas-bearing property of the reservoir and is in good agreement with the actual data, which can provide a basis for interpretation conclusions. The research results can solve the problem of identification of low resistivity gas reservoir and high resistivity water reservoir in low permeability compact sandstone, and have application value.
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