Abstract:Thickness analysis and velocity analysis are two aspects of thin-reservoir study. Thin-bed thickness analysis using seismic informations has been recommended in score literatures. This paper Iays stress on thin-bed velocity analysis. The formula far cernputing the approximate velocity in thin bed is derived using pre-stack amplitude information, the stark theary of thin-bed reflection information, ana time-distance formulas for uniform medium and continuous medium, Results of practical application Show this method is quite good.