Abstract：The velocity regularities of seismic waves in sandstone are emphatically studied by comprehensively analysing previous authors velocity results of P and S-waves in various rocks. The velocity regularities of P and S-waves in water-saturated and gas-saturated sandstones have been derived from the comprehensive analysis and study. They can be expressed as two parabolas and four empiric Vp-Vs formulas. It is pointed out that some researchers linear fitting of velocity data is only applied to a particular area or a particular formation while the parabola formulas have wide adaptability. Four empiric formulas and the relevant figures in this paper favour AVO analysis, lithology regularity recognition in multiwave exploration, and the discovery of hydrocarbon accumulation area.
