Abstract：Although the ordinary stack velocity analysis method has already matured,the ordinary NMO equation is based on the supposal that the shot and receiver points are located a same horizontal datum plane.In surface-relief area,the error of velocity analysis is unable to be negligible even using floating datum method.The method of stack velocity analysis based on relief surface presented in the paper uses double-square-root equation to compute the travel time of reflections,which is suitable to use in the area where the topography is severely relief.The tests were carried out for the method by model data and field seismic data,which showed that in combination with common fix datum static correction method,the stack velocity computed by the method is more reliable and resulted velocity spectrum has better focus effect,which can obtain more velocity information in shallow layer and clearly demonstrate the structural feature.The method presented in the paper provided a tool for velocity analysis of seismic data in the area where the surface is severely relief.
