The application of velocity-independent normal moveout correction of long-offset seismic data

Abstract

The paper deals with the long offset hyperbolic curve with time, on the basis of double parameter normal moveout (NMO) velocity analysis. A non-hyperbolic time equation independent of velocity and the time-curve slope was derived. By replacing velocity and inhomogeneity parameter S with slope and slope derivative, long-offset normal moveout method independent of velocity was achieved. The simulated data and the actual data show that, this method can be used to solve the problems when the hyperbolic time equation was applied to velocity analysis. In the deep layers, the NMO will be increasingly smaller with the increase of reflection stratum depth, resulting in higher NMO velocity error and lower the accuracy of analysis. The most obvious characteristic of this method is the accuracy of NMO velocity analysis in the long offset and deep layer seismic data. This method with easy rule can be popularized and applied very widely.