Method for predicting high-quality reservoir in gravity flow channel sand

The invention discloses a method for predicting high-quality reservoir in gravity flow channel sand and relates to the field of petroleum geological engineering. The method comprises steps as follows: well logging data of gravity flow channel sand in multiple single wells are obtained, and the porosity, the rock density and the longitudinal wave velocity of corresponding gravity flow channel sand in each single well are obtained; corresponding wave impedance of gravity flow channel sand in each single well is further obtained; a porosity-wave impedance interactive chart is established on the basis, and the high-quality reservoir in the gravity flow channel sand is determined according to the chart; wave impedance inversion is performed on target gravity flow channel sand reservoir, and quantitative distribution of the target gravity flow channel sand reservoir is obtained in combination with information of the high-quality reservoir, determined according to the porosity-wave impedance interactive chart, of th